A study on Air pollution in Rwanda with reference to Kigali ... - REMA

20111A STUDY ON AIR POLLUTION IN RWANDA WITH REFERENCE TOKIGALI CITY AND VEHICULAR EMISSIONSClient: REMATHE NATIONAL UNIVERSITY OF RWANDA CONSULTANCYBUREAU (NUR-CB)Po Box 212, Butare, RwandaFinal ReportBy Dr Hermogene Nsengimana (PhD)Mr Jean Pierre Bizimana (MSc)Mr Yves Sezirahiga (MSc)Copyright: Rwanda Environment Management AuthorityMay 2011

35.4. Increase in industrial activities ...........................................................................................385.5. Increase in number of vehicles ..........................................................................................395.6. From vehicular growth to increase of air pollution ..............................................................445.7. Air pollution: a growing problem in Kigali ...........................................................................465.7.1. Combustion sources ......................................................................................................475.7.2. Transport and automobile ..............................................................................................495.7.3. Industrial sources ...........................................................................................................545.7.4. Indoor air pollution .........................................................................................................575.7.5. Progress so far made in Rwanda ...................................................................................635.7.6. Identified gaps and challenges ......................................................................................636. Propagation factors of air pollution in Kigali City ....................................................................646.1. Influence of topography ......................................................................................................646.2. Influences of meteorology ..................................................................................................666.2.1. Temperature and rainfalls ..............................................................................................666.2.2. Wind speed and direction ..............................................................................................706.2.3. Effects of air pollution ....................................................................................................756.2.3.1. Health Effects ................................................................................................................756.2.3.2. Air pollution and Climate change ...................................................................................807. Modeling the Air Pollution in Kigali City ..................................................................................817.1.1. Statistical models ...........................................................................................................827.2. Air pollution trends in Kigali City .........................................................................................847.2.1. Suspended particulate matter ........................................................................................847.2.2. Sulphur dioxide ..............................................................................................................857.2.3. Nitrogen oxides ..............................................................................................................887.2.4. Carbon monoxide ..........................................................................................................897.2.5. Ozone (O3).....................................................................................................................917.2.6. Lead (Pb).......................................................................................................................947.3. Strategies for reducing air pollution ....................................................................................957.3.1. Strategic approaches .....................................................................................................957.3.1.1. Technical strategies .......................................................................................................967.3.1.2. Vehicle technology .........................................................................................................96

47.3.1.3. Fuel technology .............................................................................................................987.3.1.4. Systemic strategies ........................................................................................................987.3.1.5. Role of international community .....................................................................................998. Existing Policy Framework .....................................................................................................998.1. Air pollution policies and regulations in Rwanda ................................................................998.2. Multilateral agreements and international conventions ....................................................1008.3. Local policies, laws, programs and strategies ..................................................................1018.4. Role of public transport planning ......................................................................................1029. Towards urban air pollution policy in Rwanda ......................................................................1039.1.1. Vision of air quality monitoring policy ...........................................................................1049.1.2. Policy statement ..........................................................................................................1059.1.3. Policy objectives ..........................................................................................................1069.1.4. Core principles .............................................................................................................1069.1.5. Pollution prevention .....................................................................................................1079.1.5.1. Air pollutant monitoring, analysis, modeling, and inventory .........................................1079.1.5.2. Pollution prevention and emissions control ..................................................................1099.1.5.3. Car emissions inspection and control program ............................................................1109.1.5.4. Oil quality standards ....................................................................................................1119.1.5.5. Tax incentive to eco-cars .............................................................................................1119.1.6. Mandate of regulatory authority ...................................................................................1129.1.7. Policy recommendations ..............................................................................................1139.1.8. Stockholder’s collaboration ..........................................................................................1139.1.8.1. Rwanda Revenue Authority (RAA) ..............................................................................1149.1.8.2. Rwanda Environment Management Authority (REMA) ................................................1149.1.8.3. Rwanda Bureau of Standards (RBS) ...........................................................................1149.1.8.4. Rwanda National Police (RNP)....................................................................................1159.1.8.5. Research institutes ......................................................................................................11510. Concluded remarks ..........................................................................................................11610.1. Conclusions .....................................................................................................................11610.2. Recommendations ...........................................................................................................119i. Establishment of continuous air pollution monitoring system/schemes in Kigali City ............119

5ii. Improving the transport system in urban areas ....................................................................120iii. Promoting the public awareness and education. ..................................................................121iv. Promoting the use of renewable energy sources such bio-fuel ............................................121v. Conduct an impact assessment on health and environment ................................................12210.3. Actions related to recommendations ................................................................................122Air pollution monitoring system/schemes in Kigali City .................................................................12211. References .......................................................................................................................124

6List of figuresFigure 1: Road network and air pollution sources in Kigali City. ................................................................... 19Figure 2: Evaporative emissions from vehicles ............................................................................................. 27Figure 3: Cause of Air Pollution, Pollutants, Associated Problems and Scale .............................................. 30Figure 4: Urban Economic Transition and Associated Environmental Agendas for Developed Countries ... 31Figure 5: Evolution of CO and SO 2 emission in Kigali City inn 2009 ............................................................. 36Figure 6: Evolution of population of Kigali City .............................................................................................. 37Figure 7: Vehicles emission by speed .......................................................................................................... 45Figure 8: Transport Air pollution shares in 2004 ........................................................................................... 45Figure 9: CO2 from consumption petroleum products in Rwanda (estimate only) ........................................ 51Figure 10: Evolution of vehicles imported in Rwanda between 2001 and 2010 ............................................ 52Figure 11: Fuel use, CO 2 and PM emission for TCS and ICS ....................................................................... 60Figure 12: Topography, land use and landscape in Kigali City ..................................................................... 65Figure 13: Variation of annual average temperature and rainfall at Kigali .................................................... 67Figure 14: Temperature trend for the measuring period 1971– 2008; city of Kigali, Rwanda. ...................... 68Figure 15: Results of PM 10 measuring route in Kigali City in February 2008 ................................................ 69Figure 16: Measurements of PM 10 for nighttimes with cold-air dynamic from the ridge to the “Marais”. ....... 70Figure 17: Impacts of calm and windy conditions on carbon monoxide levels adjacent to a major road ..... 72Figure 18: Annual trends of wind direction and speed in Kigali City between 1974 and 2010 ...................... 73Figure 19: Respiratory Illness in Policlinic du Carrefour between 2008 and 2011 ........................................ 78Figure 20: Respiratory Illness in Kimironko Health Centre between 2002 and 2011 .................................... 79Figure 21: Respiratory Illness in Kanombe Military Hospital between 2008 and 2011 ................................. 79Figure 22: Long term SO 2 Concentration within Kigali City .......................................................................... 86Figure 23: Concentration of SO2- 4 and SO 2 in sample taken in Kigali City .................................................... 87Figure 24: Long term NO-O 3 Concentration within Kigali City ....................................................................... 88Figure 25: Diagram of long term NO 2-O 3 Concentration within Kigali City ................................................... 89Figure 26: Long term C0 Concentration within Kigali City ............................................................................. 90Figure 27: Long term CO-O 3 Concentration within Kigali City ....................................................................... 91Figure 28: Diurnal Ozone (O 3) concentration in August 2009 within Kigali City ........................................... 92Figure 29: Long-term Ozone (O 3) concentration within Kigali City ................................................................ 93Figure 30: Proposed sites for air pollution monitoring stations ....................................................................119

7List of tablesTable 1: Data type and sources ......................................................................................................21Table 2: Common pollutants, sources and characteristics ..............................................................26Table 3: Different Gases emission in Rwanda in 2005 ....................................................................35Table 4: Vehicle Pollution Emission ................................................................................................40Table 5: Number of registered vehicles by category .......................................................................41Table 6 : Air pollution emission in ppm ............................................................................................46Table 7: Greenhouse Gas emissions in Rwanda ............................................................................48Table 8: Petroleum product import in Rwanda between 2004 and 2007 .........................................50Table 9: Air pollutant sources in cement factory ..............................................................................54Table 10: Level of dust emission .....................................................................................................56Table 11: Summary of the PM2.5 and CO values for TCS and ICS..................................................61Table 12: Ambient Air Quality Tolerance Limits in East African Community ...................................76Table 13: Human Health Effects of Common Air Pollutants ............................................................77Table 14: Air pollution effects on environmental climate change .....................................................81Table 15: Gases emission in Kigali City from June to-December 2009 ...........................................82Table 16: Gases emission in Kigali City in 2010 .............................................................................83Table 17: Gases emission in Kigali City in January 2011 ................................................................84

8AcknowledgmentThis <strong>study</strong> was funded by the Rwanda Management Authority (REMA) under the Ministry ofEnvironment, Lands and Forest. On the technical side, we sincerely wish to thank all REMA staff,for the tireless support that has made it possible to have reached this stage of the project. At allstages, we received the needed financial support in due time, the required data and information;and as well as the professional guidance in secondary data collection and survey. The field workwas undertaken in different areas of Rwanda by a team of field surveyors. We express ourgratitude to them for hardly working with us under pressure for a period of more than two weeks.The document has been prepared by the National University of Rwanda Consultancy Bureau teamheaded by Dr. Hermogene Nsengimana, Vice Dean of the Faculty of Science in collaboration withMr. Jean Pierre Bizimana, Lecturer in the Faculty of Science and Mr. Yves Sezirahiga, AssistantLecturer Faculty of Law.

9List of acronymsBATsCO 2COCOPDCGIS-NURCDMCERsGISGTZHEIGDPGHGIAPIRSTKISTLULUCFMDGsMINECOFINMINICOMMININFRAMININTERMINALOCMINISANTEMICNO XNISRNLCBest Available TechnologiesCarbon dioxideCarbon monoxideChronic Obstructive Pulmonary DiseaseGeographic Information Systems and Remote Sensing Research and Training ofThe National University of RwandaClean Development MechanismCertified Emissions ReductionsGeographic Information SystemsDeutsche Gesellschaft Für Technische ZusammenarbeitHealth Effects InstituteGlobal Domestic ProductGreen House GasIndoor Air PollutionRwanda Institute of Scientific and Technological ResearchKigali Institute of Science and TechnologyLand Use Change and ForestMillennium Development GoalsMinistry of Economy and Financial PlanningMinistry of Industries , Commerce and TourismMinistry of InfrastructureMinistry of Internal SecurityMinistry of Local GovernmentMinistry of HealthMotor Vehicle Inspection CentreNitrogen OxidesNational Institute of Statistics in RwandaNational Land Centre

10NUR-CBOECDO 3PbPAHPM 2.5PM 10PPMRBSRRARADRNPREMARURASPMSNCRSNCSO 2SONATUBETCSTCSUNCHSUNEPUNFCCCUN-HabitatUS-EPAVERsVOCsWHONational University of Rwanda Consultancy BureauOrganisation for Economic Co-operation and DevelopmentOzoneLeadPolycyclic Aromatic HydrocarbonsParticulate matter with aerodiameter less than 2.5 micronParticulate matter with aerodiameter less than 10 micronParts per millionRwanda Bureau of StandardsRwanda Revenue AuthorityReactive Airways DiseasesRwanda National PoliceRwanda Environment Management AuthorityRwanda Utilities Regulator AgencySpended Particles MatterSelective Non-Catalytic ReductionSecond National CommunicationSulfur dioxideSociété Nationale des TubesImproved Cooking StoveTraditional Cooking StoveUnited Nations Centre for Human SettlementUnited Nations Environment ProgrammeUnited Nations Framework Convention on Climate ChangeUnited Nations Human Settlement ProgrammeUnited States Environmental Protection AgencyVerified Emissions ReductionsVolatile Organic CompoundsWorld Health Organisation

11Executive summaryRwanda, commonly referred to as a land of thousand hills, is witnessing rapid economic growthand development, effectuated by its political stability and progressive policies. Kigali City, theCapital of Rwanda indicates a fast growing population of approximately 970,000 inhabitants. Theincreasing rate of urbanization of this city is becoming a matter of great attention. This risingpopulation and the coherent rising rate of motorization are one of the reasons for a sustainabledegradation of the urban air quality. With this regards, the Rwanda Environment ManagementAuthority (REMA) has agreed to commission a comprehensive <strong>study</strong> that analyses the currentstate of air pollution in Rwanda with emphasis on automotive air pollution and Kigali City, itscauses and drivers, the future trends of air pollution, the associated health and environmental risksand the actions to be taken.The overall objective was to develop a solid understanding of air quality in Rwanda with focus onKigali and to develop a related strategy and policy recommendations to address the pollutionissues. This <strong>study</strong> focused on pollutants resulting from vehicular emission and other activities incities according to the World Health Organisation. To achieve the above defined objective, bothprimary and secondary data collection methods have been used. The review of literature helped toidentify the existing standards, regulations and policy about air quality; the state of air pollution inRwanda with emphasis on Kigali City and its consequences on human health with a focus onrespiratory illnesses. A desk <strong>study</strong> was carried out to acquire and analyse relevant informationpertaining to the air pollution/air quality from the previous studies and from governmentinstructions.As an example, information related to the number of number and type of registered vehicles in theRwanda was collected from Rwanda Revenue Authority. Air pollution control policy framework forRwanda was investigated from Multilateral Agreements and International Conventions on airpollution prevention and climate such that Rwanda has signed such Kyoto Protocol Convention,United Nations Framework Convention on Climate Change and Vienna Convention on theProtection of the Ozone Layer. The air quality emissions standards for Rwanda and in East AfricanCommunity have been documented based on Rwanda Bureau of Standards publication.Government publications on air quality and environment policies, laws, programs and strategies

12have also been consulted in this research. These include for example the, Initial NationalCommunication under the United Nations Framework Convention on Climate Change, RwandaEnvironment Organic law, Kigali City sub-area and transport planning document, RwandaEnvironmental Health Policy, Rwanda’s Energy Policy; Cleaner Production Programme, MotorVehicle Inspection Programme ..Etc. The previous studies and recent publication on air qualityand air pollution in Kigali City have also been explored for better understanding of the existingsituation of air quality in the <strong>study</strong> area.After literature review and existing policy documents analysis, other secondary data have collectedfrom different government institutions. For instance, data on location of health facilities in KigaliCity; medical records on upper respiratory infections diseases such as cough, phlegm, influenza,whistling/wheezing of the chest, headaches and eye irritation and as well as the chronicrespiratory disease (asthma, pneumonia, bronchitis) have acquired from the Ministry of Health.The list of industries in Kigali City and the annual import/consummation of petroleum products(gasoline, diesel, and kerosene) have been gathered from the MINICOM. As meteorology andclimate are seen as the dispersion factors of pollutants and gas emissions, meteorological recordsand climate data over time on Kigali City were analysed for the weather station of KanombeInternational Airport. These included wind redirection and speed; annual average temperature andrainfalls. All theses climate were available from the “Service Meteo du Rwanda” under the Ministryof Infrastructure. As the topography also influence the dispersion of pollutant into the atmosphere,the topographic information above Kigali City was modelled using the Digital Elevation Model andthe result was overlaid to the existing road network and land uses to show where the main sourcesof air pollution such industrial zones, roads traffic lights, roundabouts and car stations and stopsare located within Kigali City. The information on indoor air pollution was gathered from otherstudies which tried to measure the PM2.5 and CO using the Traditional Cooking Stoves and theImproved Cooking Stoves in rural areas.The preliminary research findings revealed that the rapid increase in urban population of Kigali hasresulted in unplanned urban development, increase in consumption patterns and higher structure,thereby leading to the air pollution problems. This situation is exacerbated by the following: theincreasing and high vehicle density in urban centers, older vehicles predominant in vehicle time;

13inadequate inspection and maintenance of facilities; adulteration of fuel and fuel products; impropertraffic management system and road conditions, high levels of pollution at traffic intersections;absence of effective mass rapid transport system and intra-city railway networks and the highpopulation exodus to Kigali City.Concerning the current state of air pollution in Kigali City, the measurement results on suspendedparticulate matter showed that Kigali City exceeded already the recommendations of the WHO (50μg m-3). This suggests that the inhabitants of Kigali are exposed to enormous levels of PM10 duringmost of their time outdoors especial in the evening hours. A seasonal variation was found asconsistently higher dust load was found in the dry seasons which might possibly be attributed tothe prevailed meteorological conditions such as low precipitation and wind speed. Comparing theaerosol particles concentration sampled during weekend-days in Kigali City, the results showedthat the concentration of particle matter was higher in dry season than in the rainy season. In thesame line, the Diurnal Ozone (O3) concentration in August 2009 using the single monitoring systemlocated at Kigali Institute of Science and Technology revealed a higher concentration of Ozone(O3) in atmosphere in the morning between 6:00-12:00 AM. This concentration of ground-levelozone is already beyond the major environmental standards, and the problem of air pollution isalready at present. When considering the scale of industrial activities in Kigali, we can assume thatthe primary source of this pollution is motor vehicle exhaust especially caused by bad maintenanceof its emission control.Even if the sulphur dioxide released in the atmosphere of Kigali City is low when compared to theaccepted annually average recommended by East African Standard for some common substancesfound in polluted air (80 g/m 3 for industrial areas, 60 g/m 3 for residential areas; a 15 g/m 3controlled areas), the sulphur dioxide is already a concern for inhabitants. But during the dryseasons, the measures taken at KIST air quality monitoring are beyond the permissible limits. Theaverage concentration of nitrogen oxide in Kigali City was estimated between 15 and 20 g/m 3while the permissible limit value of proposed by the East African Standard for some commonsubstances found in polluted air is 150 g/m 3. This concentration level is also in the range ofaccepted limit for air quality control and monitoring guidelines for East African Community. Theconcentration of Pb level in the aerosols in Kigali City was found below the World Health

14Organization (WHO, 0.5-1.5µg/m 3 ) and East African Community recommended levels (0.5-1.0µg/m 3 ).Therefore, based on the above results, the air quality in Kigali City is still at a favourable level ascompared to most countries in the world, but the industrial activities and traffic density continue togrow. The resulting increase in air pollution is already a concern for its inhabitants. The sustainableurban management of Kigali City calls therefore to take the comprehensive measures to tackle withthis issue in order to reduce the increasing air pollution and its human health effects. Some of theelements to take into consideration to prevent or reduce harmful effects on human health and theenvironment as a whole in Rwanda are proposed by this <strong>study</strong>.

151. General Introduction1.1. BackgroundRwanda, commonly referred to as a land of thousand hills, is witnessing rapid economic growthand development, effectuated by its political stability and progressive policies. “Vision 2020”envisages Rwanda as a modern and economically strong nation and a regional leader ofdevelopment in Africa. Kigali City, the national capital, which celebrated the 100 th year of itsfounding in 2007, is one of the fastest growing cities in Africa and has the highest rate ofurbanization (MININFRA, 2009a). Kigali indicates a fast growing population of approximately970,000 inhabitants. The increasing rate of urbanization of this city is becoming a matter of greatattention. This rising population and the coherent rising rate of motorization are one of the reasonsfor a sustainable degradation of the urban air quality. Poorly maintained, old mopeds, motorcycles,heavy machines and vehicles cause an increasing concentration of different air pollutants.Climatological parameters as well as air pollutants measured indicate a rise from 1971 to 2008(Henninger, 2009). These have been observed globally but the characteristics and scale of the airpollution problem in Rwanda in general are not known; nor has the problem been researched andevaluated to the same extent as in industrialized countries.It is in this context that the Rwanda Environment Management Authority (REMA) has agreed tocommission a comprehensive <strong>study</strong> that analyses the current state of air pollution in Rwanda withemphasis on automotive air pollution and Kigali City, its causes and drivers, the future trends of airpollution, the associated health and environmental risks and the actions to be taken.1.2. RationaleAir pollution in Kigali may be aggravated as development occurs, and as the country becomesindustrialized with the growing of the cities, increasing traffic, rapid economic development andindustrialization, as well as higher levels of energy consumption. The high influx of population tourban areas, increase in consumption patterns and unplanned urban and industrial developmentwill lead to the problem of air pollution. Today, air pollution is widespread in Kigali where vehiclesare the major contributors and in a few other areas with unknown concentration of industries andthermal power plants. Vehicular emissions are of particular concern since these are ground level

17vehicular emission and other activities in cities according to the World Health Organisation. Thissubmission provides the execution modalities of the consultancy by researchers from the NURConsultancy bureau1.4. Objectives and scope of workMore specifically the scoping of the <strong>study</strong> is as follow:• To present the case of Rwanda with emphasis on Kigali regarding air pollution and itsconsequences on human health with a focus on respiratory illnesses; this will be donethrough a literature review. There are some studies available from the Ministry of Healthand other institutions;• To conduct an assessment of the human health risk for people living in Kigali; this can betackled through literature review and statistical analysis of available data on health risk inKigali;• To undertake the identification of the main sources of air pollution, their volume andanalyze the trend in the future with regard to the increase of sources of pollution;• To gather all data on measurements so far taken on air pollution in the country and wherethere are gaps in data the consultant will conduct measurements of pollution to fillthe gaps;• To conduct an assessment of the knowledge/information/data gaps and proposeappropriate solutions;• To assess the existing standards/regulations and policy response then proposeappropriate solutions;• To report on the forecast of air pollution indicators and its risk in the coming decade; thiswill be mainly based on various studies so far undertaken;• To review the measures in place and those to be taken by local and central government ofthe city of Kigali to reverse the trends; this will be based on literature review and interviewswith all stakeholders.• To formulate recommendations and suggestions to help solve the problem; this will bedone through literature review and from the own experience of the consultant about localplanning and sustainable development. This will include a sustainable cooperation orinstitutional framework between the concerned programmes and institutions.

18• To assess and bring recommendations on standards/policy and regulations regarding carsmoke as well.2. MethodologyTo achieve the above defined objectives, the following activities have been undertaken in differentphases and the following have been used: literature review, data collection, data processing andanalysis and final report.2.1. Literature reviewThe review of literature helped to identify the existing standards, regulations and policy about airquality; understand the case of Rwanda with emphasis on Kigali regarding air pollution and itsconsequences on human health with a focus on respiratory illnesses. This activity also allowedbetter understanding and assessing the human health risk for people living in Kigali.Various studies available from the Ministry of Health and other institutions have been consulted inorder to know the consequences of air pollution on human health in Kigali City with a focus onrespiratory illnesses. We will review the existing reports and database available in the fieldprovided by different institutions dealing with air quality issues, as well as sources of air pollutionwith the main focus on vehicular emission. These institutions include REMA, The Ministry ofEnvironment and Natural resources, the ministry of infrastructure, the Ministry of Industry andCommerce, Rwanda Revenue Authority, etc.2.2. Data collectionThe data collection purpose was to identify the main sources of air pollution, their volume; and togather all data on measurements so far taken on air pollution in Rwanda. Where there were gapsin data, this <strong>study</strong> also was supposed to conduct measurements of pollution to fill the gaps. Bothprimary and secondary data methods were used.2.2.1. Primary data collectionField work was carried out in selected sites in the Kigali city, to fill in the gaps in existingmeasurements. The sites have selected according to identified site during literature review andfield visit that represent a potential risk. This selection was guided by the geography of the KigaliCity (altitude, topography and transport activities), The existing gaps some sample sites have

19completed, taking into account major pollutants such as CO2, CO, SO2, NOx, hydrocarbons.Sample sites in Kigali city were supposed to be selected and air pollutant such as CO2, SO2, NOx,Hydrocarbons, Particulate matter analyzed. These sites were identified according the volume ofvehicular traffic, the proximity to the airport, industrial activities and other main sources of airpollutants such as landfill sites. The same sites were located using the Global Positioning system.The main streets and road network in Kigali have digitized and displayed using ArcGIS9.3 softwareand along which the vehicular emissions concentration were supposed to be measured andanalysed. Sampling sites will be located at the heavy traffic roadsides, bus stops (Nyabugogo,Remera, SONATUBE, City Centre, etc), car stations, industries, garages, and on the major trafficlight points. All the instruments will be installed about 1 m above ground level. The following map ofthe road network in Kigali City will be used for sampling.Figure 1: Road network and air pollution sources in Kigali City.

20The sampling was conducted during heavy traffic rush hours on sunny days (Between 8:00-9:00AM and 03:00-04:00 PM). The geographic coordinates of these points have been taken using theGlobal positioning System 1 . As the sample sources of the air pollution measurements do notcapture the full spatial variation of air pollution from traffic road the Geographical InformationsSystems (GIS) 2 was used as main tool to assess within the city the variations of exposure to trafficpollution sources. This was assessed by measuring distance from residences to roads, or bymodelling air pollution concentrations from nearby emission sources. This possibility of higherspatial resolution of exposure assessment was necessary for the ability to detect long-term effectsof traffic on chronic respiratory disease using the residence/location information from clinicalrecords reported by health centres and hospitals within Kigali City. These medical records mayinclude for example demographic characteristics, medical history, and the results laboratory testsperformed during hospitalization. The medical records of previous hospitalizations or outpatientvisits have been also reviewed to ascertain a prior history of respiratory diseases in the <strong>study</strong> area.To analyse the exposure of people to the vehicle air pollution in Kigali City, ArcGIS9.3 softwarewas used to assign exposure to traffic-related air pollution to each patient based on their geocodedresidence at the time of hospitalization. A precision at Umudugudu level was required for the <strong>study</strong>.We used three different measures as surrogates for exposure to traffic-related air pollution: dailytraffic near the patient’s residence, distance to major roadways, and distance to a bus route. Wewill calculate the daily traffic within 100 m and 300 m of the patient’s residence. For each road, wecalculated its traffic contribution as the product of the length of the road segment falling within thecircle and its annual average daily traffic (i.e., the average number of vehicles circulating on theroad each day). The traffic contributions from each road were added to the overall daily trafficwithin the circle area. We also calculated the distance from the patient’s residence or residentialsettlements to the nearest primary highway. The surveys instruments have been used to collect theprimary data are shown in the annexes.1 Global Positioning System (GPS) is a satellite based navigation system made up of the network of 24satellites placed into the orbit by the U.S. Department of Defense. It was originally intended for militaryapplications, but in the 1980s, the U.S. government made this system available for civilian use.2 Geographic Information Systems (GIS) is computerized systems, hardware, software and proceduresdesigned to support the capture, management, manipulation, analysis, modeling, and display thereferenced data for solving complex planning and management problems.

212.2.2. Secondary data collectionAlthough this <strong>study</strong> included field activities for covering the existing gaps in data, the findings andanalyses were build on previous reports on the prospects and challenges related to the air pollutionin Rwanda with reference to Kigali city and vehicular emissions. The latter comprises deskreviews dating back to early date when the concept of air pollution was incepted in Rwanda. Forindoor air pollution, the studies related to combustion methods used at household level weredocumented.The assessment of effects of air pollution of the human health risk for people living in Kigali, thedata and information on chronic respiratory diseases were collected from epidemiological recordedby health centres and hospitals within Kigali City. The following are the health facilities that havebeen visited to collect the required medical records for this <strong>study</strong>. Kabuye Health Center, KicukiroHealth Centre, Kibagabaga District Hospital, Muhima District Hospital, Kimironko Prison Hospital,Kanombe Military Hospital, CHUK Reference Hospital, King Faysal Reference Hospital andPoliclic du Carrefour Health Centre.Information on registered vehicles fleet from 2007 to 2011 was acquired from other previousstudies like the one on potential of sustainable liquid biofuel production in Rwanda, carried out byGTZ (2011). This helped to know the increase number of vehicle per category in last five year suchas buses, cars, semi-trailer, jeeps, micro-bus, minibus, motorcycles, pick-up, special engine andtrailers. This type information was collected from Rwanda Revenue Authority.The following table summarizes the institutions that have been visited and the type of data/information collected from each institution.Table 1: Data type and sourcesInstitutionsRequested DataMotor Vehicle Inspection Centre • Engine gas emission inspection and cars maintenanceRwanda Bureau of standards • Air quality emissions standardsRwanda Revenue Authority • Number and type of registered vehicles in the countryas of May 2011.

22Rwanda EnvironmentManagement Authority• Air pollution control policy frameworkKigali City • Information related for example to public transportplanning, highway road planning, road upgrading andmaintenance, traffic management, separation of heavyduty cars.• Shapefile of road network (category of roads) in KigaliCity from Kigali Conceptual Master plan project• List of garages, number of roundabouts, location ofmain dumping sites and waste disposals, Seweragesystems; list of Biogas projects and their location;location of quarrying activities…etcMINICOM • List of industries, Gasoline, diesel, and keroseneimports and consumption.MINISANTE • Location of health facilities in Kigali City; medicalrecords on respiratory chronic diseases such asMININFRA • Meteorological and climate data on Kigali Cityincluding the nearest weather stations, the recordedmeteorological data over time including Wind directionand speed; annual average temperature, dairytemperature, rainfallCGIS-NUR • Digital Elevation Model above Kigali CityNational Land Centre • Main lands cover such forest- Mburabuturo, montKigali- Aerial photos from NLCNational Institute of Statistics ofRwanda• Households cooking methods- Number of charcoalbags- used in Kigali City, Improved stoves2.3. Data processing and analysisThis phase consisted of the assessment of the knowledge, information, data gaps in order topropose appropriate solutions. We adopted qualitative and quantitative methods for data analysis.Data from secondary data sources regarding on-going air pollution studies was descriptivelyanalyzed linking them to the consultant experiences and knowledge. Textual data from surveys,interviews, which constitute the major source of additional data, was synthesized to show the levelof pollution vs. documentary sources; to establish patterns of the current institutional and individual

23conception in air pollution; and stakeholders’ attitudes, opinions, and general thoughts on the levelof investment in the air quality by the different partnerships etc. Geographic Information Systems(GIS) techniques have been be used to map and identify the sensitive sites, among others,altitude, climate, road map, industry map, population of the city.3. Insight on Urban Air Pollution and Human Health Risks3.1. Defining the key conceptsAir quality protection is a key element in ensuring sustainable livelihoods for both present andfuture generations. Before addressing the issues related to air quality and air pollution resultingfrom the rapid urbanization in order to conduct an assessment of the human health risk for peopleliving in Kigali City, it is very important to have a common understanding and agreed on workingdefinition of key concepts related to urbanization process and their implications to air pollution andhuman health risk in urban areas.3.1.1. Urbanization and urban environmentIn 2008, for the first time in history, over half of the World’s population lived in urban areas and by2050 this will have risen to 70 per cent. Most of the growth in the world’s population over the next20 years will be in and around the urban centres in low- and middle-income countries – which aremainly concentrated in developing countries (UN-Habitat, 2009). Along with this, a populationdensity in urban areas is sharply boosting urbanization and poses enormous pressures on urbanenvironment resulting in environmental problems including air pollution (UNEP, 1997).Urbanization is a process of relative growth in a country’s urban population accompanied by aneven faster increase in the economic, political, and cultural importance of cities relative to ruralareas. In most countries it is a natural consequence and stimulus of economic development basedon industrialization (Sobbotina and Sheram 2000). However, air pollution has been aggravated bydevelopments that typically occur as countries become industrialised: growing cities, increasingtraffic, rapid economic development and industrialization, and higher levels of energy consumption.Sub-Saharan Africa is one of the least urbanized regions in the world, but the urban population inAfrica is growing very rapidly (Mabogunje, 1995). With this growth comes pollution. Povertystricken citizens in Africa, particularly in the urban population, are most negatively impacted by

24poor air. The causes of air pollution are multiple. Because many households are using charcoal orwood for energy, the amount of carbon dioxide produced by African cities has been on the rise.The 1991 global greenhouse emissions of South Africa, Ex- Zaire, and Nigeria ranked them amongthe top fifty countries in terms of their contribution (Mabogunje, 1995). The people that live in Africaare exposed to indoor and outdoor air pollution that can cause many different health problems. Theindoor pollution partly comes from the increased use of wood and charcoal in cooking.Even the industrialized countries, with higher standards of living and greater numbers of cars,produce far more air pollution and greenhouse gases than developing countries; they can reduceenvironmental hazards. A number of promising technologies are candidates for lowering vehicleemissions, including particle traps, a system to reduce nitrogen oxide emissions, preheatedcatalytic converters and electronic vehicle controls. For further emission reductions, new engineand after treatment technologies may require fuels that are free of metals and have zero sulfurcontent and a low content of polycyclic aromatic hydrocarbons (Krzyzanowski et al., 2005). Most ofdeveloping countries do not have this new technology or capacity to do so. The consumption is farlower but the expensive energy-efficient or clean-up technologies are economically impractical forthese countries. For these reasons environmental problems occur more often in developedcountries.3.1.2. What is air pollution?Air is made up of 78% nitrogen 21% oxygen, under 1% carbon dioxide, and trace amounts of othergases.The World Health Organization (WHO) defines air pollution as "substances put into the airby the activity of mankind into concentrations sufficient to cause harmful effects to health, property,crop yield or to interfere with the enjoyment of property” (WHO, 1997a). Air pollution means “thepresence or threatened discharge, from whatever source, of solid, semisolid, liquid or gaseousmatter or any combination thereof, in the ambient air in sufficient quantities and of suchcharacteristics and duration which: Injures or threatens to injure human, plant or animal life; ordamages or threatens to damage property; or unreasonably interferes with the comfortableenjoyment of life and property” (Elsom, 1992; UNEP, 2004). In local context, the Organic LawDetermining the Modalities of Protection, Conservation and Promotion of the Environment inRwanda defines the atmospheric pollution as “a voluntary or accidental contamination of theatmosphere and the surrounding air, gas, smoke, any particles or substances that may endanger

25biodiversity, human health and their security or disrupt agricultural activities, disrupt installations orthe nature of tourist sites and mountains”(Government of Rwanda, 2005).3.1.3. Sources of air pollutionThe main sources of air pollution which are man made relate to transportation, industry,combustion fuels, industrial processes and use of pesticides. More specifically the pollutantsinclude suspended matter, sulfur dioxide, nitrogen dioxide, hydrocarbons and ozone due topopulation growth, urbanization, industrialization and increased use of motor vehicles. Similarly theWHO (1997b) analysis identified problems of limited capacity in terms of funding, equipment andhuman resources to measure, assess, control and mitigate air pollution; inadequate information onair pollution and its impacts; limited public awareness and limited enforcement of existing national,regional and international legislations.Figure 1: Main source of urban air pollutionSource:http://upload.wikimedia.org/wikipedia/commons/1/14/Air_Pollution Causes%26Effects.svgThe figure above is the schematic drawing of the causes and effects of air pollution where: (1)greenhouse effect, (2) particulate contamination, (3) increased UV radiation, (4) acid rain, (5)increased ground level ozone concentration, (6) increased levels of nitrogen oxides.

26Pollution from urban atmosphere is due to air pollutant emissions and transmissions. Emissions ofsulfur dioxide have as main cause the activities in the steel industry, the oil refineries, the motorvehicles, the thermo-electric power stations. Nitrogen oxide emissions are largely caused byelectricity and thermal industry, road traffic and manufacturing industries (UNEP, 2004). Engineemissions from road traffic are an important source of pollution around the world (Alpopi andColesca, 2010). There are three broad sources of air pollution from human activities; stationary orpoint, mobile, and indoor air pollution. Industries, power plants, etc are the causes of stationary airpollution, where as indoor air pollution refers to pollutions from open fires for cooking and heating.It is mostly a problem in developing countries, and its effect become intense in rural areas. Mobileor vehicular air pollution is particularly a serious problem in urban areas (Kathuria, 2001).Pollutants can be classified as either primary or secondary. Usually, primary pollutants aresubstances directly emitted from a process, such as ash from a volcanic eruption, the carbonmonoxide gas from a motor vehicle exhaust or sulfur dioxide released from factories. Secondarypollutants are not emitted directly but they are produced by reactions between primary pollutants.Rather, they form in the air when primary pollutants react or interact. An important example of asecondary pollutant is ground level ozone (UNEP, 2004). Ozone gas is not usually emitted directlyinto the atmosphere, but at ground-level is created by a chemical reaction between oxides ofnitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight. Motor vehicleexhaust and industrial emissions, gasoline vapours, and chemical solvents as well as naturalsources emit NOx and VOC that help form ozone (Mito, 2010). Some pollutants may be bothprimary and secondary: that is, they are both emitted directly and formed from other primarypollutants (Alpopi and Colesca, 2010). There are also natural sources such as wind-blown dust andsmoke from fires. Some forms of air pollution create global problems, such as upper atmosphereozone depletion and global warming. These problems are very complex, and require internationalcooperative efforts to find solutions. The table below summarizes the common air pollutants andtheir sources.Table 2: Common pollutants, sources and characteristicsPollutants Description SourcesCarbon monoxide (CO) Colorless, odorless gas • Vehicles indoor sources, includingkerosene, wood burning, natural gas,coal, or wood-burning stoves and

27heatersLead (Pb) Metallic element • Vehicles burning leaded gasoline• Metal refineriesNitrogen oxides (NOx )Gaseous compoundsmade up of nitrogen andoxygen• Vehicles• Power plants burning fossil fuels• Coal-burning stovesOzone (O3 ) Gaseous pollutant • Vehicle exhaust and certain otherfumes• Formed from other air pollutants in thepresence of sunlightParticulate matterSulfur dioxide(SO2 )Very small particles ofsoot, dust, or other matter,including tiny droplets ofliquidsGaseous compoundmade up of sulfur andoxygen• Diesel engines• Power plants• Industries• Windblown dust• Wood stoves• Coal-burning power plants andindustries• Coal-burning stoves• RefineriesSource: (United States Environmental Protection Agency 2003; United Nations for Environment Programme 2004; andWorld Health Organization 2006)According to the United States Environmental Protection Agency (US-EPA), emissions from anindividual car are generally low, relative to the smokestack image many people associate with airpollution. But in numerous cities across the country, the personal automobile is the single greatestpolluter, as emissions from millions of vehicles on the road add up. Driving a private car is probablya typical citizen’s most “polluting” daily activity.With regards to the sources of automobileemissions it is well known that the power to move a car comes from burning fuel in an engine.Pollution from cars comes from by-products of this combustion process (exhaust) and fromevaporation of the fuel itself as shown in the figure below.Figure 2: Evaporative emissions from vehicles

28Source: (US-EPA, 1994)During the combustion process, gasoline and diesel fuels are mixtures of hydrocarbons,compounds which contain hydrogen and carbon atoms. In a “perfect” engine, oxygen in the airwould convert all the hydrogen in the fuel to water and all the carbon in the fuel to carbon dioxide.Nitrogen in the air would remain unaffected. In reality, the combustion process cannot be “perfect,”and automotive engines emit several types of pollutants:• “Perfect” Combustion: Fuel (hydrocarbons) + Air (oxygen and nitrogen) carbon dioxide +water + unaffected nitrogen.• Typical Engine Combustion: Fuel + Air unburned hydrocarbons + Nitrogen oxides+Carbon monoxide + Carbon dioxide + water.The most exhaust pollutants are hydrocarbons, nitrogen oxides (NOx), carbon monoxide (CO),and carbon dioxide (CO2). Hydrocarbon emissions result when fuel molecules in the engine donot burn or burn only partially. Hydrocarbons react in the presence of nitrogen oxides and sunlightto form ground-level ozone, a major component of smog. Ozone irritates the eyes, damages thelungs, and aggravates respiratory problems. It is our most widespread and intractable urban airpollution problem. A number of exhaust hydrocarbons are also toxic, with the potential to causecancer.Under the high pressure and temperature conditions in an engine, nitrogen and oxygen atoms inthe air react to form various nitrogen oxides, collectively known as nitrogen oxides (NOx).

29Nitrogen oxides, like hydrocarbons, are precursors to the formation of ozone. They also contributeto the formation of acid rain. Carbon monoxide (CO) is a product of incomplete combustion andoccurs when carbon in the fuel is partially oxidized rather than fully oxidized to carbon dioxide(CO). Carbon monoxide reduces the flow of oxygen in the bloodstream and is particularlydangerous to persons with heart disease. In recent years, the carbon dioxide (CO2) as a pollutionconcern has started to be viewed as a product of “perfect” combustion. Even if carbon dioxide doesnot directly impair human health, it is however a “greenhouse gas” that traps the earth’s heat andcontributes to the potential for global warming (UNEP, 2004; US-EPA, 1994).Apart from the exhaust pollutants, other hydrocarbon pollutants (as evaporative emissions) alsoescape into the air through fuel evaporation. With today’s efficient exhaust emission controls andtoday’s gasoline formulations, evaporative losses can account for a majority of the totalhydrocarbon pollution from current model cars on hot days when ozone levels are highest. Basedon an overview of automobile emissions of the United States Environmental Protection agency(US-EPA), the evaporative emissions occur several ways:• Diurnal: Gasoline evaporation increases as the temperature rises during the day, heatingthe fuel tank and venting gasoline vapors.• Running losses: The hot engine and exhaust system can vaporize gasoline when the car isrunning.• Hot soak: The engine remains hot for a period of time after the car is turned off, andgasoline evaporation continues when the car is parked.• Refueling: Gasoline vapors are always present in fuel tanks. These vapors are forced outwhen the tank is filled with liquid fuel (US-EPA, 1994 pp.2-3).Each country, region and area has different environmental problems attributed by their degree ofdevelopment, culture, geography and characteristic. It was argued that there were certainenvironmental problems associated with the degree of cities’ economic development namely low,medium and high income levels and they were called grey and green agenda, respectively. Forurban air pollution problems, each agenda can be described.

30Figure 3: Cause of Air Pollution, Pollutants, Associated Problems and ScaleAgenda Causes Pollutants AssociatedproblemsScaleBrownIncreasing number of vehicleHeavy usage of diesel powered vehicleHeavy usage of obsolete vehiclesHeavy usage of motor cycles (2 stroke)Unpaved and/or poorly maintained streetOpen burningInadequate infrastructureLow quality of fuelLittle emission control & technology inindustryPresence of industries (e.g. ceramic,brick works, agrochemical factory)Particulate matters (PM10,PM2.5)Lead (Pb)Sulphur dioxide (SO2)Oxides of nitrogen (NOx)Ozone (O3)Hydrocarbons (HCs)Carbone monoïde (CO)Hydrogen fluoride (HF)Heavy metals (e.g. Pb,Hg, Cod etc.)Human healthproblem (acute)Ecosystem healthproblem (acute)LocalGrayIncreasing number of vehicleUse of motor cycles (2 stroke)Use of obsolete vehiclesUse of diesel powered vehiclesInadequate infrastructureImproved but still low quality of fuelSome emission control & technology inindustryParticulate matters (PM10,PM2.5)Sulphur dioxide (SO2)Oxides of nitrogen (NOx)Ozone (O3)Hydro cabre (HFCs)Carbone monoïde (CO)Human healthproblem (chronic)Ecosystem healthproblem (chronic)Greenhouse gasemission (global)Acid rain (global)RegionalGreenLarge number of vehicle populationLimited dry deposition of pollutantsWaste incinerationFine particulate matter(PM2.5)Oxides of nitrogen (NOx)Ozone (O3)Hidno carbona (k.o.)Human healthproblem (chronic)Greenhouse gasemissionStratospheric ozonedepletionGlobalSource: (Ishii, 2004)Endocrine disruptionsubstances (EDS)Acid rainLong-rangetransport

31In current high income cities, level of traditional pollutants closely related to brown and greyagenda (Table 1) are currently less pronounced due to enforcement of laws and regulations(OECD, 1995). Yet it is also known that commonly these cities suffer from new arising problemssuch as fine and ultra fine particulate matter (PM0.1-PM2.5), photochemical ozone and greenhousegases as they were described as a green agenda.Figure 4: Urban Economic Transition and Associated Environmental Agendas for Developed CountriesIntroduction of Legalenforcements & controls?Brown agendaGrey agendaGreen agendaLowMediumHighIncome levelSource: OECD, 1995In low and medium income cities, situations were slightly different from those affluent cities in thepast. Historically in those high income cities, there was a situation that a brown, grey and greenagenda came in sequence over relatively longer time scale and, policy and initiatives such asstrong legal enforcements and effectively overcame arising problems (Bai and Imura, 2000).The impact of air pollution on health depends on how much pollution people actually experienceduring their daily lives, which is called their exposure. Exposures can be great even whenemissions do not affect the outdoor environment significantly, if the source of emissions is close tothe population. It has been estimated that nearly half the world’s population still uses solid fuels(biomass and coal) for household cooking and space heating, mostly in developing countries. Inthe proper conditions, biomass (wood and agricultural residues) can be burned quite cleanly,producing mostly carbon dioxide and water. Such conditions are difficult to achieve in small-scaleinexpensive stoves, however, and the actual emissions of health damaging pollutants are quitelarge per unit fuel, although the total emissions are not large in the context of overall fuel use.

32Air pollution has long been a problem in the industrial nations of the world in particularly fordeveloped countries. It has now become an increasing source of environmental degradation in thedeveloping nations of the world. An air pollution cost refers to motor vehicle air pollutantdamages, including human health, ecological and esthetic degradation. Tailpipe emissions arepollutants released directly from vehicle exhaust pipes. Lifecycle emissions include both tailpipeemissions and indirect emissions from fuel extraction and refining, vehicle manufacturing, andconstruction of facilities for transportation. Different factors influence air pollution include differentgases produced during transport, householder cooking, gases coming from industrials, such asSO2, NO2, NO, NOx, …. Etc. The topography and the meteorological conditions of an area arealso considered as dispersion factors gas emission from the air pollution sources and thereforeresponsible of differences in air pollution concentration from one area to another.4. Study design4.1. Guiding research questionsData collection methodology will be question-guided as follows: (i) what are the respiratory andother diseases related to air pollution in Rwanda and in Kigali in particular and appropriatemeasures undertaken if any? (ii) How and under what conditions can air pollution in Rwanda bebetter fostered so as to realize adaptive capacity for responding to environmental changes? (iii)What are the main sources of air pollution and the factors that may in the future influence the airpollution trend in Rwanda, increase or decrease the pollutants? (iv) What are the existing gaps inthe existing data? (vi) What are the strategies undertaken to Reduce Air Pollution from Transport?What are the respiratory and other diseases related to air pollution in Rwanda and in Kigali inparticular and appropriate measures undertaken if any?4.2. Pressure-State-Response Based ApproachThe above defined research questions have been addressed by reviewing different documents inthe Ministry of Health, Hospital records, National Institute of Statistics and other institutions withvested interest in air pollution related diseases–such as previous research work, reports on theexisting diseases, purposely to establish the link of the type of disease with air, including measuresundertaken, geographic location of the patients, and Distribution of population or populationdensity. In addition, this review will boost knowledge base of air pollutant, activity of the patient(work) and frequency of the diseases. Documented information was supplemented with data

33generated through interviews with local community in selected area of the Kigali city, relevantinstitution and industries. The interviews will be open-ended and loosely structured to allow forflexibility and adaptation depending on the interviewee(s) in question. Interviews will particularlyhelp researchers to understand the level of non reported diseases cases, understanding of airpollution problems. They will simultaneously probe the necessity to take into consideration somepractical solutions to improve the situation.To answering the question of how and under what conditions can air pollution be better fostered inRwanda so as to realize adaptive capacity for responding to environmental changes, the air qualityissues have been explored from relevant literature? The main objective was to establish theoreticalstandpoints with reference to how air pollution has been viewed, debated and refined and, itssensitivity to the human health. Literature sources have been complemented by face-to-faceinterviews and reflective case studies, each covering a range of professionals and practitioners inthe air quality or environment guideline/standards, engaging them in debates on institutional andon their own field experiences. Reflective case studies were used to elucidate stakeholderperceptions of challenges, opportunities, key issues and outcomes of the <strong>study</strong>. The wholepurpose was to gather enough data and knowledge on the existing gaps in air qualitymeasurement, assess the existing standards/regulations and policy response in order to proposeappropriate solutions. More specifically, the following data have been collected for the <strong>study</strong> areasusing the Pressure, State and Response (P-S-R) based framework. The P-S-R framework hasbeen particularly useful in representing the way in which pollution affects the urban environment,for example by looking at the various “pressures” exerted on the urban environment which affect its“state” (urban air quality) and consequently call for a “response” to deal with the situation airpollution in urban areas (von Schirndin, 2002).4.2.1. Pressures of urban air pollutionAs pressures of urban air pollution, the related data and information that were to be collectedconcerned with: increase in urban population; increase in industrial activities; increase in number ofvehicles; increase in power generation and in door pollution at households. As the problem of airpollution in urban area may also be aggravated by inadequate power supply for industrial,commercial and residential activities, additional information on the quality and types of bio-

34combustible used was colleted. This information helped to know the power generation units thatare emitting high level of NOX and SOX. In addition, non point sources that contribute to the totalemission such as waste burning, construction activities, quarrying point, roadside airborne dustydue to the vehicles movement have been investigated in this <strong>study</strong>. As topographical andmeteorological conditions can strongly influence the spatial climatic modifications and the spatialdistribution of air quality and air pollution, the digital elevation model of Kigali City was mappedusing the exiting contour lines at a scale of 1: 50000. Climate data such as temperature,precipitations, wind direction and speed that have recorded by the nearest stations of Kigali Cityhave been collected from the meteorological services under the Ministry of Infrastructure(MINIFRA) and analyzed.To analyse the impact of the increasing number of the vehicles on air pollution within Kigali, thetransport-related indicators that can be used in the context of pressure-state-response (P-S-R)framework. Pressures leading to air pollution was the number of car or car use levels; vehicleownership per capita, proportion of population regularly using public transport; average road trafficvolumes, densities (cars, trucks, buses); greenhouse gas emission levels by vehicle category;emission levels from transport vehicles (carbon monoxide, nitrogen oxides, ozone, hydrocarbons,particulates, lead, by vehicle category); chlorofluorocarbon emission levels from vehicle airconditioners and the proportion of vehicles failing maintenance/emissions tests.4.2.2. State, exposure and effects of air pollutionState of urban air pollution was analyzed using indicators such as annual exceedance of airpollution standards; air pollution levels (carbon monoxide, volatile organic compounds,hydrocarbons, nitrogen oxides, ozone, lead, dust, particulates); traffic density (vehicles per km);rates of traffic flow and prevalence of odors. Exposures information tried to estimate the numberof people that may be exposed to air pollution in Kigali City using indicators such proportion ofpopulation living in proximity of dense traffic; proportion of population exposed to elevatedconcentration levels of traffic-derived air pollution; proportion of population exposed to air quality inexcess of standards. Human health effects were assessed based on mortality and morbiditylevels in respect of: acute and chronic respiratory illness such as asthma, reduced lung function;lung cancer; cardiovascular disease and stress-related disorders.

35In relation to the increase in number of vehicles, slow growth of road infrastructure and highgrowth of transport performance, this <strong>study</strong> also assessed the action and strategies that havebeen take to monitor/reduce the air pollution. Various actions can be taken to decrease the risks oftransport to human health include for example the production of safer, cleaner cars (for examplecars with gas exhaust cleaning devices, electric- or solar-powered cars), improved vehicleinspection and maintenance programmes, changes in fuel characteristics and quality, exclusion ofprivate cars from city centre, development of cycling paths and pedestrian areas, improvement ofpublic transport (for example, railways, tramways and buses can be made less polluting, less noisyand safer), as well as the introduction of new public transport systems. Improved town planningmeasures can also reduce demand for transport, for example, by siting housing closer to workareas. Parking areas in the city can also be limited.5. Urbanization and air pollution in Rwanda5.1. IntroductionAir pollution is an international problem, which has many effects and facts to the life of the worldpopulation. African countries, including Rwanda also are also concerned with air pollution problem.It is known that Rwanda is a landlocked republic in Equatorial Africa. The capital Kigali can bementioned as a typical African city due to its rising population and the rising rate of motorization.Different pollutants produced e.g. by a high-usage rate of mopeds or open fireplaces burningwoods for cooking and household chores could be detected. Climatological parameters as well asair pollutants were measured within the urban area. The following table and figure presents the totalnumber of gases emitted in Rwanda during the period of 2005.Table 3: Different Gases emission in Rwanda in 2005GasesCarbon dioxide (CO2) 530.88Méthane (CH4), 71.31Nitrous Oxide (N2O), 10Nitrogen Oxides (NOx) 14Carbon monoxide (CO), 2327COVNM 42Sulfur Oxides (SOx). 18Emissions in Gg

36Source:In the above figure, it is clear that thequantity of gases that was emitted inthe atmosphere in 2005 wasdominated by carbon monoxide (77%)followed by carbon dioxide (18%) andmethane with (2%). But, when youFigure 5: Evolution of CO and SO2 emission in Kigali City inn 2009consider the evolution of CO and SO2emission during the period of year2009 at the station IO104-1-204 atKigali city, it was found that the carbondioxide SO2 is the most pollutant gas inurban areas of Rwanda such Kigali City.Source:5.2. Factors (sources) of Air PollutionThe main categories of air pollution sources in many countries of the world are vehicularemissions, industrial emissions, fuel use for domestic purposes such as cooking, and a potentiallylarge miscellaneous category, which includes burning of household wastes and emissions from

Population37small businesses and cremation grounds. While particulates from natural sources are notconventional pollutants, their contributions are typically taken into account in inventories of totalsuspended particulates since natural sources can be both a major contributor to pollution and asource of uncertainty. However, natural dust particles are coarse and do not contribute significantlyto particulate matter fractions that actually get deposited in human lungs. The following are maincauses of air pollution: Vehicles, Industries and Power plant, Domestic fuel combustion,Householder woods combustion Miscellaneous causes5.3. Impact of rapid urbanizationUrbanisation in Rwanda currently stands at 18% and is increasing at a rate of 4% per annum. By2020 is expected that over 50% of the population will be living in urban centres. Kigali, by far andaway the largest city, representing 44% of the urban population, illustrates the challenges faced bycities and the built environment in Rwanda. Kigali has grown, fuelled by the return of refugees andthis has led to large unplanned and underserved neighborhoods. Secondary centres are unable toattract returnees, as they are unable to provide solid bases for employment or economic services.Unplanned developments are estimated at 8,500 to 10,000 units annually in Kigali, representing90% of buildings in the city (Byamukama et al., 2011).According to the 2002 Rwanda National Census, between 1991 and 2002, Kigali had an averagegrowth rate of 9%. The city’s population increased from 350,000 in 1996 to 603,000 inhabitants in2002 as shown in the figure 1 (Durand-Lasserve, 2005; MINECOFIN, 2002; MININFRA, 2004;MININFRA, 2008). This increase results from theEvolution of population of Kigali Citycombined effect of natural growth, rural-urban100000090000080000070000060000050000040000030000020000010000001907 1962 1970 1978 1991 1996 2002 2006YearYearPopulationmigrations, and the return of refugees to thecountry from the neighboring countries (Pérousede Montclos, 2002). Kigali, as being the capital ofRwanda, is also experiencing a considerablegrowth and urban planners anticipate that withinthe next 10 years, the population will double(Aibinu, 2001; Sano, 2007).Figure 6: Evolution of population of Kigali City

38Kigali is built on a hilly landscapes sprawling across ridges which are separated by swamp valleysand wetlands. The main business and residential settlements are located on top of the ridges,which are enclosed by the steep slopes and sometimes on the bottom valleys (Bizimana andSchilling, 2010; Urwibutso, 2008). While this urbanization is regarded as a driving force foreconomic development, it should however be planned, controlled and well directed (MININFRA,2008). This rapid increase in urban population has resulted in unplanned urban development,increase in consumption patterns and higher structure, thereby leading to the air pollutionproblems. This situation is exacerbated by high vehicle density in urban centers, older vehiclespredominant in vehicle time; inadequate inspection and maintenance of facilities; adulteration offuel and fuel products; improper traffic management system and road conditions, high levels ofpollution at traffic intersections; absence of effective mass rapid transport system and intra-cityrailway networks and the high population exodus to the urban center (SURBANA, 2010). While theurban population is expected to reach 30% of the national population by 2020 in Rwanda; howeverthe urban development should not contribute towards pollution of surrounding sub-urban and ruralareas (MINECOFIN, 2000).5.4. Increase in industrial activitiesAs it is typical in developing countries, most of the industries are located in urban areas and about63 per cent of industries are located in and around Kigali. Among the challenges facing theindustrial sector, the inadequate pollution control is the biggest one. Kigali provides a largeproportion of the city’s industrial employment but consequently a larger portion of the urbanenvironmental problems. A significant number of factories which form the industrial base in Kigaliare located in a low-lying area called the Gikondo- Nyabugogo wetland. The factories, as well asthe densely populated homesteads located on the adjacent hill slopes, have no proper liquid-wastedisposal systems, and consequently pollute soils, groundwater and the surface water andatmosphere. Many of the factories use out-dated technologies that are associated with energydemands and waste generation to levels that have adverse impact on the environment, and renderthe operations expensive and unsustainable (REMA, 2009).For this <strong>study</strong>, list and names of industries as highly air polluting source in urban areas will beacquired from the Ministry of Commerce and Tourism (MINICOM). These industries will be

39categorized for example as integrated iron and steel, thermal power plants, copper/zinc/ aluminiumsmelters, cement, oil refineries, petrochemicals, pesticides and fertiliser units...etc. The level ofpollution will be assed terms of type and quantity of emitted pollutants and having pollution controlfacilities to comply with the standards. The geographic coordinates of each industry will be takenusing the GPS 3 device in order to show their location and spatial distribution within Kigali City.5.5. Increase in number of vehiclesAlmost all cities have changed to motorized road vehicles, which has increased the use of fossilfuels and increased greenhouse-gas emissions. This explosive growth in the number of roadvehicles is a big problem in many cities. Many city centers have major difficulties trying to cope withthe chaotic automobile traffic. The traffic jams are extremely bad in many cities and transport trafficin the city area at least during the rush-hours is really slow. The pollution is high due to constanttraffic and causes respiratory diseases to city habitants (UNCHS, 1996)The need for increased transport of people, materials, goods and products together with risingincome levels and the desire for personal mobility have also led to a rapid increase in motor vehicleownership in Kigali City. Concomitantly with this increase in the number of motor vehicles, thecombustion of fossil fuels has increased substantially, as has the release of gaseous pollutants andparticulates. From literature, it was estimated that motor vehicles account for more air pollutionthan any other single human activity. For example, more than half of the global emissions ofcarbon monoxide, hydrocarbons and nitrogen oxides from fossil fuel combustion derive fromautomobiles, both gasoline- and diesel-powered, and the proportions may be significantly higher incity centres. Transport-associated emissions affect the state of the environment by increasing airpollution levels, particularly carbon monoxide, volatile organic compounds, hydrocarbons, nitrogenoxides, ozone and lead, as well as dust and particles. Diseases and ill-health effects associatedwith transport include chronic respiratory illness, asthma, reduced lung function, cancer and heartdisease, which might be caused or exacerbated by air pollution. Benzene and polyaromatichydrocarbons from car exhausts and leaked oil and lubricants are recognized carcinogens, as areasbestos fibres (von Schirndin, 2002) .3 Global Positioning System

41Fine particulates( PM10; PM2.5)CFCS and HCFCLeadSource:Inhaleable particles.A class of durablechemicals.Element used in olderfuel additives.Tailpipes, brakelining, road dust, etc.Air conditioners andindustrial activities.Fuel additives andbatteries.Human health, aesthetics.Ozone depletion,climate changeHuman health,ecological damagesLocal andRegionalIn Rwanda, the number of cars and motors are increasing considerably. The following table showsdifferent figures of registered vehicles by category during the period from: 2005-2009. The pollutionemissions of different gases also increase according to the numbers of motors vehicles.Transportation is a major contributor of many air pollutants. These shares are even higher incertain circumstances, such as in cities, along major roads and in tunnels.Table 5: Number of registered vehicles by categoryCategory BeforeCum. atCum. at2005 2005 2006 2007 2008 2008 2009 2009Bus 70 15 16 46 91 238 27 265GlobalCar 8,526 1,796 889 1,805 1,922 14,938 1,372 16,310Half- trailer 66 13 12 12 23 126 38 164Jeep 4,381 1,793 676 1,032 1,327 9,209 1,236 10,445Microbus 63 7 2 13 15 100 26 126Minibus 2,687 724 279 212 657 4,559 193 4,752Motorcycle 7,243 4,913 3,571 5,374 7,818 28,919 4,714 33,633Pick up 5,747 1,497 859 1,290 1,225 10,618 818 11,436Special engine 59 26 14 83 62 244 86 330Trailer 334 56 68 120 49 627 43 670Truck 1,374 276 171 301 198 2,320 186 2,506Unknown 0 0 1 1 1 3 2 5Total 30,550 11,116 6,558 10,289 13,388 71,901 8,741 80,642Local

42A simple representation of the trend showing the increasing of number of vehicles per categories.Figure: Number of registered vehicles per year

Figure: Cumulative number of vehicles categories43

445.6. From vehicular growth to increase of air pollutionTranslating numbers of vehicles to gross emissions of pollutants requires the development ofrepresentative values, called emission factors that for each vehicle category relate the quantity of apollutant released into the atmosphere to the level of activity associated with each vehicle type. AnEemission factor F can be defined as F where E is the amount of pollutant released (inAgrams) and A is the level of activity, typically measured in kilometers driven. The emission factor,F, depends on a number of variables, such as the intrinsic nature of the technology; the power ofthe vehicle; and vehicle operating conditions, including engine temperature, vehicle speed, ambienttemperature, deterioration from age and usage, quality of maintenance, and the quality of the fuel.For all these reasons, emission factors within vehicle categories are subject to a good deal ofvariability. Emission factors are typically developed for each vehicle type, and an assessment ofthe variability must be performed to derive a range of values for emissions under differentoperating conditions. Typically, emission factors are reported for a set of ideal conditions.(Examples: for a particular speed, operating temperature, and vehicular age) and with correctionfactors that can be used to extrapolate to other operating conditions).There are several reasons to expect large emissions for vehicles such including maintenance ofvehicles, average traffic speeds. From experience, it has been observed that slower speeds (

45Figure 7: Vehicles emission by speedFigure 8: Transport Air pollution shares in 2004Source:Another key issue in the derivation of emission factors is the quality of fuel used. In manydeveloped countries of the world, the quality of fuel, especially adulteration of gasoline by

46kerosene, is a particularly important, if understudied, issue. This problem is almost universalamong motorized three-wheeled vehicles (auto-rickshaws), which for the most part are not ownedby their operators. Kerosene is heavily subsidized because it is seen as an important fuel forhousehold cooking for lower-income groups. Since the price of gasoline per liter exceeds that ofkerosene by a factor of five, auto-rickshaw operators typically adulterate their gasoline fuel with asmuch as 30% kerosene.Emissions of major pollutants depend on emission factors and levels of usage of different vehicles.Annual emissions from a category of vehicle can be calculated, as shown in the above formula, bymultiplying the emission factor provided by the annual usage (in kilometers) for that category. Airpollution is increasing when the number of vehicles is increasing. The following table shows theestimated emission values of different gases during the period of 2009-2011in ppmTable 6 : Air pollution emission in ppmEmission CO CO 2 NO NO 2 NO x O 3 SO 2From 5491.65985 - 3535.841058 7601.142476 10827.57025 419053.4661 4776.7029June20092010 12133.69927 - 379.6039 0 290.6327 624917.8182 6005.228967January-February2011Source:1469.3932 - 0 0 0 70580.66068 283.26692875.7. Air pollution: a growing problem in KigaliAir pollution is a growing problem in urban areas in Rwanda. The major source of air pollution arefor example the transport sector with 52% of imported petroleum product and used vehicles,manufacturing industries such cement, and steel mils, agriculture and livestock activities includingpesticides, machinery and manure; and mining activities which are contributing to the emission ofdusty. Due to the lack of adequate data and information to inform decision maker, the magnitude ofair pollution in Rwanda may currently not be seen as serious problem. However, if proactive andintegrated approach is not taken immediately in addressing the air pollution problem, the problem

47is already serious from the fewer studies done. Moreover, the air pollution is not easy to detect inRwanda because the country don't have so far the suitable equipments (Barigye, 2009).For instance, the urban air pollution is growing as economic development drive of Rwandaincreases combustion of the fossil fuel for industrial processes and transportation. Kigali City, thecapital of Rwanda, is built in hilly country sprawling across about 4 ridges and the valleys inbetween. The tops of the ridges have an average elevation of 1,600 meters while the valleys arearound 1,300 meters. The city is almost ringed by higher hills, the highest of which is Mount Kigali,with an elevation of 1,850 meters above sea level. Because of the high altitude, Kigali has apleasant tropical highland climate. Temperatures range from 20°C to 21.6°C year round. There arefour seasons: Long rains from mid-March to mid-May, short rains from mid-September to mid-December; a long dry period from mid-May to mid-September; and a short dry season from mid-December to mid-March. Average annual precipitation is 900 mm.The increase of population in Kigali City was accompanied by an increase of the number ofvehicles, which could adversely affect the quality of air in the city. Other factors that may contributeto worsen the air quality include pollution from industries, domestic cooking, soil blown dust andwaste combustion (Ingabire, 2009). During the dry season, the concentration of ground-level ozoneis already beyond the major environmental standards, and the problem of air pollution is already atpresent (Mito, 2010). Therefore, comprehensive measures must be taken to tackle with this issue.For example, installation of an inspection system on motor vehicle exhaust, establishment ofregulations on car emission and air pollution environmental standards, tax incentive introduction forimportation of environmentally friendly cars, reinforcement of air pollution monitoring system wouldbe essential.5.7.1. Combustion sourcesBy combustion sources is meant operations where primarily fossil fuels, coal, natural gas, petrol,diesel and furnace oil are burnt to obtain energy. This includes power plants, industrial boilers, andautomobiles. Thermal power plants are major sources of SPM, SO2 and NOx. Depending on thetype of used fuel, the emission of one or more of these pollutants may be of environmentalsignificance.

48Nitrogen Oxides formed in combustion processes are usually due to either thermal fixation ofatmospheric nitrogen in combustion air or to the conversion of chemically bound nitrogen in thefuel. Thermal fixation occurs when combustion temperature is above 1600°C. For natural gas anddistillate oil nearly all NO results from thermal fixation. For residue oil and coal, the contribution toNO emission from fuel bound nitrogen may be significant. The concentration of NOx formedincreases with increase in excess oxygen maintained in the combustion process and with theincrease in temperature of the furnace.Rwanda has one of the lowest emissions per capita in the world, estimated at 0.65 tonnesCO2/person (including land use change), compared to a global average of 4.63 tonnes CO2/person.In January 2010 the GoR submitted its Second National Communication (SNC) to the UNFCCCwith a GHG emissions inventory for the reference year, 2005 (Table 1.1). The majority of GHGemissions were CO2 (87%) at 531 Gg, dominated by transport (52%) and industrial processes(28.5%). Total CO2 sequestration was 9,000 Gg and land use change (conversion of forests andgrasslands) was -545 Gg making Rwanda a net carbon sink. CO2 emissions from biomass andbunkers (aviation) were 7,228 Gg and 17 Gg respectively but are memo items only. The aggregateemissions or total CO2 equivalent, used for measuring global warming potential, amounted to5,010.4 Gg in 2005, dominated by agriculture (78%) and energy (18%). Nitrous oxide (N2O) andmethane (CH4) are the most potent greenhouse gases contributing 62% and 26% of aggregatedemissions. Four key sources contribute 91% of aggregate emissions: N2O from agricultural soils(57%); CH4 from enteric fermentation in domestic livestock (19%); CH4 from residential energy fromfuel; combustion (8%); CO2 from road vehicles (5%) (Byamukama et al., 2011).Table 7: Greenhouse Gas emissions in RwandaGreenhouse Gas SourcesCO2CH4N2ONOxNOxNMVOCsSOxCO2 eqGgGgGgGgGgGgGgGgTotal National Emissions 531 71 10 14 2,327 42 18 5,010Energy (fuel combustion) 380 20 0 14 361 42 18 891,3Energy Industries45 - 0 0 0 0 0 -(petroleum)

49Manufacturing industries28 - 0 0 0 0 1 -and constructionTransport 274 - 0 7 17 3 0 -Other (residential - biomass) 34 20 0 7 344 38 17 -Industrial processes (cement151 - 0 0 0 0 150,5and lime production)Agriculture - 49 10 0 9 0 0 3909,9Land-use change and0 0 0 0 1957 0 0 10,9forestry (LULUCF)Waste (disposal and handling) 3 - 0 0 0 0 47,25Source: Byamukama (2011)5.7.2. Transport and automobileTransport plays a fundamental role in the lives of societies and individuals: how people interact,work, play, organize production, develop cities, and get access to services, amenities and goods isinextricably linked with the development of mobility and the choices people make about it. Insocieties that rely heavily and increasingly on private motorized transport, vehicles are expected tobecome safer, more luxurious and powerful, and to be driven more frequently. These expectations,however, often do not take account of the ensuing consequences: increased fuel consumption,greater emissions of air pollutants and greater exposure of people to hazardous pollution thatcauses serious health problems (Krzyzanowski et al., 2005).

Million litres imported50Rwanda has an extremely small number of road transport vehicles, with only 75,000 registeredtotal vehicles (vehicles recorded since 2001 to 2009), of which over 30,000 were motorcycles. Thiswas equivalent to around 8 vehicles per thousand people (note other sources have slightly differentvehicle numbers) (Watkiss et al., 2009). Rwanda’s transport sector is entirely dependent onimported fuel and consumes approximately 75% of all the country's imported petroleum products.Gasoline and diesel predominate, and 167 million liters were consumed in 2008. Demand isforecast to grow at around 10% per annum until 2020. Imports of petroleum products constitutearound 25% of the total import value of the national economy. Diesel consumption is about 38%higher than gasoline. Around 52% of diesel imports are dedicated to the transport sector, with therest used for electricity generation (GTZ, 2011).Table 8: Petroleum product import in Rwanda between 2004 and 200712010080PremiumDieselKerosene60402002004 2005 2006 2007Source: (Watkiss et al., 2009)Rwanda Vision 2020 estimates that petroleum product consumption will increase by > 10% perannum. It will therefore be an increasing source of CO2 (Government of Rwanda, 2008). Theseestimates have been used by Watkiss et al.,(2009) to project petroleum product emissions inRwanda as shown below.

G g C O2 eq51Figure 9: CO2 from consumption petroleum products in Rwanda (estimate only)250020001500LP GF urnace oil and HF OK eroseneJ et fuelDieselGasoline100050002003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020Source: (Watkiss et al., 2009)As shown in the above figure, the main driver for the growth of CO2 is increased petrol and diesel.Low carbon options would therefore have benefits in reducing the potential future problem of airquality especially in Kigali City. There is also wider transport issues associated with strongincreases in transport demand, notably urban congestion. According to Watkiss et al., (2009),there is so far no low carbon plan for the transport sector currently for Rwanda. The increasingnumber of motor vehicles in Rwanda and particularly in Kigali may be one source of toxic airpollution. Children are more vulnerable to the impacts of toxic air pollution because their bodies arestill developing. Traffic pollution may also a cause of rising asthma rates.

Number of Vehicles52Figure 10: Evolution of vehicles imported in Rwanda between 2001 and 2010Evolution of Vehicles Imported in Rwanda from 2001 to 201060005000400030002000100002001 2002 2003 2004 2005 2006 2007 2008 2009 2010Number of Vehicles 2267 3540 2149 2632 2793 2555 4474 5249 3741 3098Source: Rwanda Revenue Authority, 2010However, the recently published energy policy has objectives regarding the lower carbon in thefuture, as follow: (i) promote energy conservation and efficiency through encouraging propermaintenance of vehicles and good driving practices; (ii) programmes have to be introduced toensure proper maintenance of vehicles and fuel-efficient driving practices should become the normin Rwanda; (iii) encourage the development of affordable and well run mass transport systems sothat the proliferation of individual goods and passenger vehicles is reduced; (iv) reduce pollution byencouraging the use of environmentally friendly fossil fuels such as unleaded petrol and lowsulphur diesel; and (vi) encourage research into alternative fuels for transport purposes, such asethanol, methanol and biodiesel(MININFRA, 2009b)There are close interactions between almost all forms of energy use and the natural and humanenvironment. The National Energy Policy and National Energy Strategy statements in this regardare as follow: (i) Rwanda am committed to mitigating the adverse impacts of traditional energysupply chains and to developing and disseminating environmentally friendly energy technologies.(ii) Comprehensive environmental standards are to be set and strictly enforced for all levels of thepetroleum sector. (iii) Wherever possible, development of environmentally sound energy is to besupported through accessing internationally marketable carbon credits through the Clean

53Development Mechanism (CDM) or through the voluntary carbon emissions market. Applicationsshould be made to obtain Certified Emissions Reductions (CERs) which require that projectpromoters can demonstrate “additionality”, so that the planned reductions would not occur withoutthe additional incentive provided by emission reductions credits. In other cases, Verified EmissionsReductions (VERs) should be pursued, using internationally recognized standards such as theGold Standard on the Voluntary Carbon Standard to enhance their value in voluntary carbonmarket. The proceeds from VERs will be invested by government in further renewable andsustainable energy projects.Finally, through the Capacity Building and Transactions Support project, Government of Rwanda isdeveloping the capability to evaluate proposals for carbon credit projects and ensure that Rwandamaximizes the benefits that can be derived from the CDM programme and voluntary carbon market(MININFRA, 2009b p.16) .Transport represents the fastest growth source of emissions, and is a key issue in Rwandabecause of growing urbanisation. However, it is the hardest of all sectors to advance low carbonoptions and usually the least cost-effective (i.e. the highest marginal cost per tonne CO2 abated).Avoiding the future growth from this sector seems to be challenging. Policies to address transportalso have high political barriers, because policies are often unpopular, and may have someconsequences (for the poor). Options can be broadly categorized as follows: vehicle efficiencyimprovement e.g. newer vehicles; advanced technologies; demand side measures e.g. behaviouralchange; Fuel switching e.g. biofuels; and modal shift e.g. private to public transport systems(Watkiss et al., 2009).Even if transport accounts for the majority of petroleum products and then in combustion emissionsin Rwanda (MININFRA, 2004), the urbanized population is however is still at low level(approximately 16%), and therefore the localized concentrations of transport emissions at countrylevel may not yet contribute significantly to health externalities compared with indoor air pollutionfrom biomass burning.

545.7.3. Industrial sourcesIndustries emit a wide variety of process-specific pollutants gaseous organic and inorganiccompounds, complex vapors that undergo phase transformation after emission into theatmosphere, with process-specific composition such as heavy metals. As industries are consuminglots of fossil fuels, the consumption of these fuels eliminates in the atmosphere pollutantsubstances containing carbon, sulphur and nitrogen. The two sources of air pollution that can bediscussed here comprise for example the cement manufacture and sulphuric acid manufacture.From the cement manufacturing points, raw materials include lime, silica, aluminum and iron. Limeis obtained from calcium carbonate. Other raw materials are introduced as sand, clay, shale, ironand blast furnace slag. The process consists of mining, crushing, grinding, and calcining in a longcylindrically shaped oven. Air pollutants can originate at several operations of cement factories aslisted below.Table 9: Air pollutant sources in cement factoryPollutantsRaw material crushing and grindingOven operation and coolingProduct grinding and packagingEmissionsParticulatesParticulates, CO, SO 2 ,NOx, HCParticulatesSource: UNEP, 2004The control of emission of particulate matter is economically viable as the cost of collected dust(raw material and product) pays for control measures. From the sulphuric acid manufacture points,Sulphuric acid is produced from sulphur, which is burnt to obtain SO2. Sulphur dioxide is convertedto trioxide in presence of vanadium pentaoxide catalyst. The sulphur trioxide is absorbed inrecycling concentrated sulfuric acid. Unreacted SO2 escapes with the flue gas. New large plantsnow a days use double conversion double absorption process realizing above 99 percent efficiency(UNEP, 2004).The current economy of Rwanda is dominated by agriculture and services while the industry is stilla relatively small part. In the medium to long term, the service sector is the target for Rwanda’seconomy. At present, manufacturing dominates industrial output. The share of mining and

55quarrying in GDP is low (though important for exports). The largest increase within industry hasbeen in construction, which has grown from 36% to 46% of industrial output. This is partlygovernment infrastructure expenditure, and partly a private sector boom in residential construction.The energy used in industry is captured in the early energy emissions. Due to historic poweroutages, an estimated 75% of Rwandan firms have access to private generators. An average of45% of these Rwandan firms’ electricity comes from their generators. The fertiliser plant using LakeKivu methane for urea production would also increase industrial emissions, as would the potentialgas to liquid plant (Watkiss et al., 2009).The presence of a large number of small scale industrial plants makes pollution control moredifficult because small-scale operations are more financially strapped and less technologicallycapable than large scale ones, and their numbers make the already lax monitoring andenforcement of pollution control laws even more difficult. Criterion pollutants (SOx, NOx, CO, CH4)that are released as a part of industrial combustion may be quantified to the first order on the basisof overall estimates of fuel used and average emission factors for various industrial activities.Determination of the levels of specific toxic substances released into the environment, on the otherhand, requires plant-specific data for each toxic compound. Construction of inventories for specificchemicals is a resource-intensive and difficult activity owing to its process-specific nature.Particular emission from industrial combustion of fossil fuels can be characterized.As policy response to reduce air pollution from industrial sources and factories, the RwandaBureau of Standards (RBS) is to develop National Air Quality Standards that all industries shouldmeet. A list draft standards has recently been published by RBS including the Air Quality –Emissions to the Air by Cement Factories Guidelines and the Air Quality Tolerance Limits ofEmission Discharged to the Air by Factories. The limits refer to the level of dust emission in themain stack only of a given system in the Cement Factories. Typically, these systems are rawgrinding, coal (or solid fuel) grinding, clinker cooler, kiln (main stack), and cement grinding. Undernormal operating conditions where the design is appropriate and the equipment is properlymaintained and operated, the following level of dust emission can be achieved (EAC, 2010a).

56Table 10: Level of dust emissionDevice Abbreviation Emission(mg/Nm 3 )Multiclone MLTC 2000Fabric filter – sheet type/mech. Rapping FF-sm 150Electrostatic precipitator – lower efficiency EP-le 500Fabric filter – sleeve type/jet pulse cleaning FF-jp 50Electrostatic precipitator – high efficiency Ep-he 50Source: East African Community 2010For example, if a plant has two cement grinding systems, one equipped with a FF-jp and the otherwith a FF-sm, the first system would have to comply with a dust emission limit of 50 mg/Nm 3 andthe second, a limit of 150 mg/Nm 3 . For the latter, a grace period of up to one year would be givento achieve the lower optimal limit.The proposed limits for Oxides of nitrogen (NOx) assume that: None uses fuel with high nitrogencontent, have or make use of modern abatement techniques such as flame cooling, low-NOxburner, staged combustion and selective non-catalytic reduction (SNCR). The immediate emissionlimit can be achieved by eliminating improper operating conditions such as non-uniform raw mealquality or feed, high excess air, over burning, damaged burner pipe, improper cooler settings, etc.The second level may require some investments such as modern fuel feed and firing system, newburner pipe, clinker cooler improvements, automation, etc. Emission limits based on the use ofBest Available Technologies (BATs) as mentioned above are not being considered at this time.The proposed limits for sulfur dioxide (SO2) assume that: None uses raw material with highsulphur content; none have or make use of modern abatement techniques such as absorbentaddition, wet or dry scrubber, etc. As for NOx the first immediate limit is based on achieving properoperating conditions. The lower limit is based primarily on the installation of a high impulse/lowswirl burner. Emission limits based on the use of Best Available Technologies (BATs) asmentioned above are not being considered at this time (EAC, 2010a).

575.7.4. Indoor air pollutionFuel combustion from domestic sources is a major cause of pollution in many countries of theworld. Although health risks from these sources appear to be greatest in rural areas, there aresignificant emissions in cities as well. In addition to ambient air pollution associated with industryand transport, indoor air pollution (IAP) is becoming an important problem in developing cities. IAPrefers to pollutions from open fires for cooking and heating. Smoke emissions from burning wood,coal, cattle dung, and other biomass fuels are a significant source of indoor Particulate Matter (PM)in many cities, although these sources can also contribute to outdoor PM. The combustion ofbiomass and coal is usually incomplete and often occurs in simple stoves, which are either smallpits or open clay boxes. The resulting emissions contain large quantities of Particulate Matter,carbon monoxide, and unburned hydrocarbons. Emissions from biomass combustion also containa large number of polyaromatic hydrocarbons, such as benzoapyrene, that are mutagenic andcarcinogenic. In addition to these organic substances, coal and kerosene smoke also contains SOxand trace metals.Besides biomass, coal, kerosene, and liquefied petroleum gas (LPG) are the main fuels fordomestic uses such as cooking and heating. From a health viewpoint, however, it is the use ofsolid-biomass-based fuels that are burned inefficiently and vented in close proximity to people thatis the cause for greater concern. Household fuel usage is the key determinant of domestic airpollution, with fuels such as dung and wood that are lower on the “energy ladder” beingsignificantly more polluting than modern clean-burning fuels such as LPG and electricity.Intermediate fuels such as kerosene are less polluting and more efficient than biomass-basedfuels. PM10 and other emissions from biomass fuels can be two or more orders of magnitudehigher than those for modern fuels for the same level of end-use energy provided. The use of moreefficient smokeless stoves and better ventilation mechanisms can reduce the levels of emissionsand exposure. However, although improved stoves help mitigate pollution exposures, they do noteliminate them. In the long term, only clean fuels can help eliminate exposure.Indoor air pollution, which is mostly ignored by the people affected by and government as well, hasa serious effect on the health of children as well as residents in the house. According to the WorldHealth Organization (WHO), worldwide IAP is responsible for about 1.6 million deaths a year,

58particularly of young children and women. According to a <strong>study</strong> undertaken by the universities ofHarvard and Berkeley, smoke from wood fires for cooking will result in 10 million premature deathsin Africa by 2030. What is more, the poor are predominantly affected, as they are more reliant onbiomass energy sources. A <strong>study</strong> in South Africa on poor household fuel impacts indicated thatexternalities mainly from fires, burns and air pollution increased the economic cost of paraffin(kerosene) by over 78% and wood by a significant amount (Borchers, 1997; Borchers andAnnecke, 2006; Thorne, 1997). Addressing this situation is therefore the key to the MDGs.The major cause of IAP is burning of solid biomass fuels (wood, animal dung and agriculturalresidues) in open or traditional cook stoves built in poorly ventilated kitchens. Pollution fromdifferent types of cooking stoves using coal, fuelwood, and other biomass fuels contributes to someextent, to the overall pollution load in urban areas. Those most vulnerable to the effects of airpollution (the young, the old and the sick) spend most of their time indoors, where they may besignificantly exposed. Indeed, the highest exposures to air pollution occur in the indoorenvironment in developing countries, mainly from biomass and coal combustion for cooking andheating. Other pollutants may originate from cigarette smoke, construction materials and methods,materials for furniture and fittings, paints and solvents. The indoor environment can also beaffected by pollutants in the ambient environment, and vice versa (von Schirndin, 2002).More than two billion of the world’s poorest people still rely on biomass and coal-burning forhousehold energy needs. Use of these fuels indoors leads to levels of indoor air pollution manytimes higher than international ambient air quality standards allow for, exposing poor women andchildren on a daily basis to a major environmental air pollution and public health hazard.(Nuwarinda, 2007; WHO, 2002a; WHO, 2003). A <strong>study</strong> in the Netherlands revealed that highlevels of SO2 are associated with most of Chronic Obstructive Pulmonary Disease (COPD) a nonspecificterminology commonly used to describe the spectrum of various diseases causinglimitation of respiratory airflow for example asthma, chronic bronchitis, and emphysema. The same<strong>study</strong> revealed that a significant association was found between fine particles measurements andvisits to hospital emergency departments (Stephen et al., 2007). The most serious health risks arefrom burns and smoke inhalation-with the severity of such risks dependent on the length and levelof exposure. In poorly ventilated dwellings, especially when biomass fuels are used to heat rooms

59in which people sleep, carbon monoxide poisoning is a serious hazard. Exposure to carcinogens inemissions from biomass fuel combustion has been confirmed in studies in which exposed subjectswere personal monitoring equipment and women who spend two to four hours a day at the stoveand have high exposure levels of total suspended particulates. This must be presumed to causesome risk of respiratory cancer (WHO, 1992).More than 80 percent of Rwanda’s population (approximately 20 million people), principallycomprising the rural poor are exposed to dangerous levels of IAP and many people suffer fromproblems related to IAP we can estimate that 2.7 percent of the national burden of disease inRwanda is attributed to solid fuel use and this can causes 7500 deaths per year In urban areas ofRwanda, where large part of the population is using fuel wood, charcoals, and kerosene forcooking purposes in their daily life, it is unreasonable to ignore the air pollution that results fromthese burnings. The rapid urbanization of Kigali City was accompanied by a tremendous increasein the flow of fuel wood and charcoal. The fuelwood inflow has increased by 87% from the annualsupply of 8,776,080 kg in October 1999 to 15,321,600 kg in September 2004. At the same time,the charcoal flows into Kigali have increased by 95% from the annual supply of 2,031,934 kg inOctober 1999 to 3,960,600kg in October 2004 (Christophersen, 1999). Throughout Rwanda, themain sources of lighting energy are oil (64 %), wood (17.5 %) and kerosene (10 %). For the urbanhouseholds firewood (52 %) and charcoal (39.5 %) are by far the main sources of energy used,other sources being gas and kerosene. Even in Kigali city, only 37 % of the households useelectricity (MINECOFIN, 2002).Currently, over 85% of Rwandans depend on wood for domestic energy because alternativesources of energy are unreliable and unaffordable for the majority of Rwandans, leading toextensive deforestation (Care International Rwanda, 2010). In urban area of Rwanda, almost morethan 60 % of the people use fuel wood, charcoals and kerosene for cooking as well as for otherdaily activities (Henninger, 2009; MINECOFIN, 2002). Thus the contribution of this process to theenvironment pollution should not be treated as insignificant. Nevertheless, controlling the airpollution resulting from these sources is also a problem in connection with their effect on the livingcondition of the people. For instance, taxing or charging these commodities is one method ofcontrolling the air pollution by discouraging the consumption of these commodities. But, since the

60consumption of these commodities may be more concentrated on poor households than the richones the effect of taxing or charging the commodities should be analyzed first.As the Air pollution in residential areas is a problem in Kigali City, the connection of low incomehouseholds to the national electricity grid under the Electricity Access Roll out Programme (EARP)is perceived as one of the strategic measures taken by the government to solve the issue. A <strong>study</strong>in South Africa in the Township of Leandra revealed that the electrification resulted in a significantreduction in PM10 concentrations particularly during the morning and evening peaks. There wasalso somewhat of a reduction in SO2 concentrations, although a non-local, probably industrialsource, also contributes to SO2 levels for households that are located near pollutant industries.PM10 and SO2 increased steadily again after the electrification, as the township expanded and thedomestic use of coal increased (Mugabo, 2011).Not only the heavy dependence and inefficient utilization of biomass resources for energy haveresulted in high depletion of the forest resources, but also the use of traditional cooking technology,one source of inefficient biomass resource use, has been linked to indoor air pollution and poorhealth (Damte and Koch, 2011). In response, the Government of Rwanda and other institutionshave pushed for the adoption of new cooking technologies. For instance, CARE InternationalRwanda is involved in cook stoves dissemination in Rwanda on design and testing of improvedcook stoves.Figure 11: Fuel use, CO2 and PM emission for TCS and ICS

61The training conducted Aprovecho Research Center in 18 Controlled Cooking Test with CARE staffin Huye District in 2010 revealed that fuel consumption CO and CO2 production pass a 99%confidence level t-test and PM production passes at 97%. No significant difference is foundbetween cooking time. The improved stove showed a 62% reduction in fuel use; 49% reduction incarbon monoxide CO produced and 42% reduction in PM emissions (Serrar et al., 2010).Another <strong>study</strong> tried to measure the PM2.5 and CO using the traditional cooking stoves and theimproved cooking stoves in rural areas of Rwanda has revealed the following summarized results:The average 24-hr mean PM 2.5 concentration was measured to be 2.127 mg/m 3 in before phase (with TCS)and that in the after phase (with ICS) was 0.728 mg/m 3 . The average 24-hr mean CO concentration wasmeasured to be 22.174 ppm with the TCS and 8.349 ppm with the ICS. The average percent change of theIAP concentration between the TCS and ICS were therefore 65.73% for PM 2.5 and 62.34% for CO. The datashows that the pollution levels in houses that use TCS are very high and the ICS that is promoted inRwanda is quite successful in reducing IAP. However the fact that the pollution levels are stillhigher than WHO guideline values even after installation of ICS shows that there is a need formore improvement in areas such as ventilation and kitchen management.By Kitchens, the highest and lowest 24-hr average mean PM2.5 and CO concentrations weremeasured in K1 and K2 respectively in both ‘before’ and ‘after’ measurements. In K1, themeasured mean concentrations of PM2.5 were 3.374mg/m 3 with TCS and 1.429mg/m 3 with the ICSand for CO these were 38.557ppm with TCS and 17.172ppm with ICS. In K2, the mean PM2.5 andCO were respectively 0.889mg/m 3 and 8.660ppm with the TCS; and 0.728mg/m 3 and 3.337ppmwith the ICS. The large difference in pollution levels in the two kitchens both before and after theinstallation of the ICS shows that other factors, besides the stove design, such as ventilation andcooking habits are also very important in determining IAP levels. The details of the PM2.5 and COconcentration levels observed are summarized in the table below:Table 11: Summary of the PM 2.5 and CO values for TCS and ICSBefore After P-Average%Nvalue* reductionMean SD Max Min Mean SD Max MinAverage of all

62PM2.5 36 2.127 1.797 7.129 0.212 0.728 0.652 2.900 0.093 0.000 65.73CO 36 22.174 19.672 102.560 4.250 8.349 7.245 27.620 0.200 0.000 62.34K1PM2.5 8 3.374 1.653 5.651 1.514 1.429 0.810 2.900 0.422 0.008 57.64CO 8 38.657 13.683 55.880 19.990 17.217 7.701 27.620 5.550 0.012 55.57K2PM2.5 14 2.653 1.951 7.129 0.562 0.749 0.513 1.856 0.143 0.001 71.74CO 14 26.269 23.167 102.564 4.25 8.320 5.533 22.180 2.500 0.002 68.32K3PM2.5 14 0.889 0.718 2.751 0.212 0.308 0.187 0.772 0.093 0.002 65.35CO 14 8.660 4.737 23.210 4.440 3.337 1.952 8.120 0.200 0.002 61.46• While considering the results from all three kitchens, the minimum and maximum of the mean24-hr PM2.5 concentrations observed with the TCS were respectively 0.212mg/m 3 and7.129mg/m 3 . Similarly, with the ICS these were 0.093mg/m 3 and 2.90mg/m 3 (please refer tothe table above).• Similar to PM2.5, the minimum and maximum mean 24-hr CO concentrations observedconsidering all kitchens with TCS were 4.25ppm and 102.56ppm respectively; and with the ICSwere 0.20ppm and 27.62ppm respectively (please refer to the table above).As the overall conclusion, the <strong>study</strong> has found very high levels of indoor air pollution from burningof biomass fuels, particularly in houses with poor ventilation. However, the <strong>study</strong> has also shownthat the simple, low-cost and locally built mud brick ICS can reduce the pollution levels as indicatedby concentration of PM2.5 and CO by more than 60 percent. The ICS also results in significanthealth benefits as well as other benefits such as reduced firewood consumption, cleaner kitchens,and reduced time for cooking (http://www.stovesforrwanda.com ). Overall the ICS users aresatisfied with their new stoves and feel that reduced smoke, improved health and reduced firewoodconsumption are the main benefits of the stoves. However, there is a need for more awarenessprogrammes for scaling up ICS throughout the country. The findings of this <strong>study</strong> can be used as atool for motivating people to install ICS. The <strong>study</strong> also shows that proper operation andmaintenance of the ICS is essential for fully achieving its desired results and other aspects such asimproved ventilation and kitchen management are also equally important.

635.7.5. Progress so far made in RwandaProgress in air pollution control and reduction has been made in Rwanda including theImplementation of relevant Multilateral Environmental Agreements (MEAs). As mentioned before,Rwanda is also part of to several MEAs that are of relevance to mitigation of air pollution. Theseinclude: The Vienna Convention on the Protection of the Ozone Layer and its Montreal Protocol onSubstances that Deplete the Ozone Layer; The United Nations Framework Convention on ClimateChange and its related Protocols Basel Convention on the Control of Transboundary Movements ofHazardous Waste and their Disposal; and The Stockholm Convention on Persistent OrganicPollutants Enforcement…etc.Rwanda Bureau of Standards (RBS) primary mandate is to develop National Standards to meetindustry, governmental, and other customer needs in a bid to promote competitiveness ofRwandan products and services, to protect health and environment. It is in this regard thatfollowing a list of Draft Standards in progress published in the issue Number 8, RBS is pleased toinform the readers about recently approved environment standards related to the air quality. Theseare: RS 542:2011; EAS 750:2010 referring to the guideline for the air quality in terms of emissionsto the air by cement factories; RS 543:2011 EAS 751: 2010 related to the air quality specification;and the RS 544:2011 EAS 752:201 Air Quality related to the tolerance limits of emissiondischarged to the air by factories.5.7.6. Identified gaps and challengesFrom this research, it was found that the regulatory regime on air pollution control and reductionstill has to be improved in Rwanda. The environment management acts exist in Rwanda butrelevant regulations and their enforcement are yet to be formulated and finalized. Limitedinstitutional capacity and technical infrastructure such as finding, equipment and human resourcehave been identified in this <strong>study</strong>. Very limited information and is another challenge as there is nosystematic quantitative assessment of the magnitude of the air quality due to inadequate capacityand resources. The level of public awareness on the air pollution problems and associated adverseeffect to human health and environment is still low. The rapid growth of rural and urban populationcoupled with poor urban planning which allows for inappropriate allocation of economic activitieswithin Kigali City is also leading to air pollution. Inadequate institutional coordination and

64collaboration between government institutions can lead to the lack of common strategies.Inadequate involvement of major stakeholders (e.g. local community, NGOs, the private sector,industries) in addressing the environmental problems has been noticed. Inadequate integration ofenvironmental considerations in the planning and development programs was also noticed in thisresearch.6. Propagation factors of air pollution in Kigali City6.1. Influence of topographySome cities have characteristic wind systems as a result of local topography. An example of sucheffects is the rising air over a warm mountain side during daytime often leading to local formation ofclouds and release of precipitation. During night, the system turns around and the cooling of themountain valley leads to stable conditions that may cause local air pollution problem. The impact ofkatabatic winds due to the topographical conditions may affect cities. Usually the impact on airpollutant concentrations is moderate, but they may lead for to high levels of local dust. Anotherexample is the warm and dry Foehn wind formed on the back-side of a mountain chain. When thewind is forced over the mountain, the air is cooled and releases moisture. The air subsequentlybecomes warmer when it is moving down-hill again. This system may then form an inversion andthen reduce dispersion of local air pollutants (Hertel and Goodsite, 2009). These temperatureinversions contributed to the accumulation of aerosol and gaseous pollutants such as sulfur dioxideand particulates.Considering Rwanda shows a distinctive relief and topography, Kigali is also situated in the centralhighlands. The main business and residential districts are on top of the ridges, which are enclosedby small valleys called “marais” where most of industries are operating. The lack of space forcesmore and more people to settle along the slopes and on the bottom valley of the hills. Though theexistence of air pollution depends on spatial distribution and of course on intensity of the sources.But pollution is not necessarily bound within the area of strongest emission (Henninger, 2009).Topographical conditions in Kigali City could therefore have a very strong influence on spatialclimatic modifications and the spatial distribution of air quality as above highlighted by (Hertel andGoodsite, 2009).

Figure 12: Topography, land use and landscape in Kigali City65

666.2. Influences of meteorologyAn air pollution problem involves three parts: the source, the movement of the pollutant and therecipient. All meteorological phenomena are a result of interaction of the elemental properties ofthe atmosphere, heat, pressure, wind and moisture. The concentration of the pollutants in theatmosphere is governed by the emission sources and micrometeorology of the region, and for airquality management, knowledge of both these parameters is vital. The importantmicrometeorogical parameters relevant to air pollution studies are wind speed, wind direction, andatmospheric stability (Niyogi and Patil, 1994) . Consequently, any <strong>study</strong> of air pollution shouldinclude the weather patterns (meteorology) of the local area because the fate of air pollutants isinfluenced by the movements and characteristics of the air mass into which they are emitted. If theair is calm and pollutants cannot disperse, then the concentration of these pollutants will build up.Conversely, if a strong, turbulent wind is blowing any pollution generated will be rapidly dispersedinto the atmosphere and will result in lower concentrations near the pollution sources. Themeasurements of wind speed and direction, temperature, humidity, rainfall and solar radiation areimportant parameters used in the <strong>study</strong> of air quality monitoring results and to further understandthe chemical reactions that occur in the atmosphere. Meteorological monitoring is then used topredict air pollution events such as inversions, high pollutant concentration days and to simulateand predict air quality using computer models (The State of Queensland, 2011).6.2.1. Temperature and rainfallsThe meteorological conditions like air temperature heavily affects the pollution levels as theygovern the dispersion conditions as well as the transport in and out of the urban area. This featureis termed the urban heat island effect because the city has a smaller albedo and therefore absorbsmore energy compared with the surrounding rural areas. There is in addition a high consumption ofenergy inside the city, as a result of domestic heating and intense road traffic, which againcontributes to release of heat. The buildings and other urban constructions form a shield for thewind, and this shielding leads to less cooling of the surfaces inside the city. Since the buildings actas heat reservoirs, the city has furthermore a less pronounced diurnal temperature variationcompared with the rural areas (Hertel and Goodsite, 2009). The ambient temperature in urbanatmosphere of larger cities is generally a couple of degrees Celsius higher than that found in

67surrounding rural areas. Temperature and sunlight (solar radiation) play an important role in thechemical reactions that occur in the atmosphere to form photochemical smog from other pollutants.Rain has a "scavenging" effect when it washes particulate matter out of the atmosphere anddissolves gaseous pollutants. A reduced particle concentration after rain improves visibility. Rainacts as a solvent for gaseous pollutants, such as sulfur dioxide, forming acid rain resulting inpotential damage to materials or vegetation where it falls. Certain geographic areas or particulartimes of the year, with frequent high rainfall are likely to have improved air quality (The State ofQueensland, 2011).Climate model scenarios based on singe station of Kigali Airport in Rwanda show the futureincreases in mean annual temperature of up to 3.25°C for the region by the end of the century.Changes in rainfall are more uncertain, though most of the models show that rainfall will increase.Limited regional climate modelling has been carried out that captures Rwanda’s unique regionalsetting and climatology.Figure 13: Variation of annual average temperature and rainfall at KigaliSource: Service Meteo du RwandaThe temperature trends for the urban area of Kigali was also analyzed by (Henninger, 2009),using the data from three meteorological stations maintained by the “Service Meteo du Rwanda”.To have a common measuring period of all three meteorological stations the 1971 and 2008 were

68observed. Fig. 3 indicates an increasing annual mean temperature of 2.6 K for a period of nearly40 years. Mainly, for the last 10 years a warming in Kigali is evident. In the first instance, thisdevelopment could be attributed to global warming, because more or less rising temperaturescould be recognized all over Rwanda during the last decades. But it could also be related to theongoing urbanization, because the temperature trend of Kigali is much higher and faster than inother parts of the country. All three stations display a mean urban temperature modification ofabout 2 K in relation to the rural stations outside of Kigali (Henninger, 2009).Figure 14: Temperature trend for the measuring period 1971– 2008; city of Kigali, Rwanda.Source: (Henninger, 2009)The same <strong>study</strong> presented the measurement results on suspended particulate matter in Kigali Cityin relation recommended values of the WHO for PM10 short time exposure (50 μg m -3 ) (WHO,2006). From measurement results of PM10 detected car traverses, first sight the morning tripsindicated a lower concentration than in the evening hours; whereas no one could really talk aboutlow concentration. For the morning measurements suspended particulate matter concentrationranges between 175 μg m -3 and 900 μg m -3 (Fig. 18; lower, blue lines). The course of themeasuring route is replicably very good. Highest values were reached between route sections 10and 16, where the route climbs up the hill, goes straight through the center of the city and leaves it

69on the other side of the ridge. The same behavior is visible for the evening hours (Fig. 18; upper,red lines). For instant, the concentration increases from 1,400 μg m -3 up to 2,400 μg m -3 . Althoughhighest levels were measured in areas with paved roads in business and commercial areas withthe highest traffic rates this result is not reassuringly, because all measured residential districts inKigali exceeded the recommendations of the WHO, too. This suggests that the inhabitants of Kigaliare exposed to enormous levels of PM10 during most of their time outdoors. So PM10 levels areincreasing in areas with high rates of traffic due to the exhaust of the vehicles and the stirring up ofdust from the ground, but also in fact of burning wood for cooking etc. within the residentialdistricts. As a matter of fact for the measurements in February daily mean PM10 levels from sunrisetill sunset reached 1,013 μg m -3 .Figure 15: Results of PM 10 measuring route in Kigali City in February 2008*For morning (lower, blue lines) and for evening measuring trips (upper, red lines).Source: (Henninger, 2009)Hazardous measuring trips have been detected for some nighttime measurements in February2008. Because of high temperatures, high solar radiation and a non-typical missing cloud cover,the Kigali City urban surface could heat up extremely, which produced a cold-air flow from the ridgeand the slopes down to the “Marais”. From these night measurements, it was found that the PM10

70concentration reached the highest levels of the day in nighttime hours. But the cold-air flow takesaway the suspended particulate matter, which tends to accumulate within the “Marais” on thebottom of the hills, the places where most residential neighborhoods could be found andagricultural fields were used. Of course this is not the rule, but it is also no snap-shot, becausethese phenomena showed up in four of ten measuring trips in 2008 and two in 2009.Figure 16: Measurements of PM 10 for nighttimes with cold-air dynamic from the ridge to the “Marais”.Source: (Henninger, 2009).Many scientists believe that the steady growth in the amount of carbon dioxide and other gasesbeing released into the air due to the global warming is the major cause of global climate change.Increasing earth temperatures could lead to an increase in the severity of droughts, heat wavesand extinction of animal and plant species and damage to coastlines from rising ocean levels. Atthe end, car emissions and the resulting the global warming also carries all sorts of additionalhealth risks. Insect-borne diseases are already spreading due to warmer temperatures.6.2.2. Wind speed and directionMeteorological data, such as wind speed and direction, and photochemical reactions betweenpollutants are combined with data from a pollutant emissions inventory for a region to model theprocesses that occur in the atmosphere. The findings of the model can be used to support

71strategies to manage the emissions from pollution sources if the causes of pollution are known andthe consequences of exceeding the threshold concentration are detrimental.If high pollutant concentrations are measured at a monitoring station the wind data recorded at thestation can be used to determine the general direction and area of the emissions. When the likelysource or sources have been identified they can then be managed to reduce the impacts on airquality. Wind speed is measured using an instrument called an anemometer. In this picture a "cupwheel" anemometer is turned by the wind which in turn generates an electrical current that is ameasure of the speed of the wind.The measurement of meteorological parameters is important to gain anunderstanding of the impacts of a region's meteorology on air pollutantconcentrations, the prediction of inversions, and for the <strong>study</strong> ofwindfield and dispersion modelling. In a <strong>study</strong> on effect ofmeteorological conditions on urban air pollution of Surat City, it wasfound that as wind speed and temperature are high the dispersion ishigh, because of which the difference in air pollutants concentration between source station anddilution station is also very high and vice versa. Among the meteorological parameters, wind speedis found to affect the dispersion of pollutants the most. The air Quality parameters such as NOx,SO2, SPM are found to be within limit (Verma and Desai, 2008). The carbon monoxide emittedfrom road traffic is well dispersed during summer by strong winds, resulting in lowerconcentrations. However, during winter, the carbon monoxide concentrations peak as the air iscalmer and does not disperse the pollutant as quickly, resulting in higher concentrations. Anexample of the impacts of calm and windy conditions on carbon monoxide levels adjacent to amajor road in Brisbane over a one-year period is shown in the graph below.

72Figure 17: Impacts of calm and windy conditions on carbon monoxide levels adjacent to a major roadSource: The State of Queensland (2011).Wind directions affect pollution concentrations, since pollutants are primarily dispersed downwindfrom sources. To account for wind direction impacts on pollution, the overall understating of airpollution concentrations, traffic flows and wind direction could be helpful to investigate vehicleemissions impacts on air pollution concentrations in different areas of Kigali City. So, the winddirection and speed for Kigali City analyzed in this <strong>study</strong> using the data from three meteorologicalstations maintained by the “Service Meteo du Rwanda” for the years between 1974 and 2010.From our results, it was found that the general annual trends of wind Direction in Kigali City usingthe single station of Kanombe International Airport is from North and North-East to the South asshown in the figures below.

73Figure 18: Annual trends of wind direction and speed in Kigali City between 1974 and 2010Winds in January at Kanombe Airport from 1974 to 1993Winds in February at Kanombe Airport from 1974 to 1993NWNNE10.08.06.04.02.00.0ESE1 - 2 m/s3 - 5 m/s6 - 7 m/sNWNNE12.010.08.06.04.02.00.0ESE1 - 2 m/s3 - 5 m/s6 - 7 m/s8 - 10 m/s8 - 10 m/sWS> 10 m/sWS> 10 m/sSWSWNWNWinds in March at Kanombe Airport from 1974 to 1993NE14.012.010.08.06.04.02.00.0ESE1 - 2 m/s3 - 5 m/s6 - 7 m/sNWNWinds in April at Kanombe Airport from 1974 to 1993NE14.012.010.08.06.04.02.00.0ESE1 - 2 m/s3 - 5 m/s6 - 7 m/s8 - 10 m/s8 - 10 m/sWS> 10 m/sWS> 10 m/sSWSWNWWinds in May at Kanombe Airport from 1974 to 1993NE20.0N15.0E1 - 2 m/s10.03 - 5 m/s5.00.0SE6 - 7 m/sNWNWinds in June at Kanombe Airport from 1974 to 1993NE20.015.010.05.00.0ESE1 - 2 m/s3 - 5 m/s6 - 7 m/s8 - 10 m/s8 - 10 m/sWS> 10 m/sWS> 10 m/sSWSW

74NWinds in July at Kanombe Airport from 1974 to 1993NE20.015.0E1 - 2 m/sWinds in August at Kanombe Airport from 1974 to 1993NE20.0N15.0E1 - 2 m/s10.03 - 5 m/s10.03 - 5 m/s5.05.0NW0.0SE6 - 7 m/sNW0.0SE6 - 7 m/s8 - 10 m/s8 - 10 m/sWS> 10 m/sWS> 10 m/sSWSWWinds in September at Kanombe Airport from 1974 to 1993NE12.0Winds in October at Kanombe Airport from 1974 to 1993NE10.0N10.08.0E1 - 2 m/sN8.06.0E1 - 2 m/s6.04.03 - 5 m/s4.03 - 5 m/s2.02.0NW0.0SE6 - 7 m/sNW0.0SE6 - 7 m/s8 - 10 m/s8 - 10 m/sWS> 10 m/sWS> 10 m/sSWSWWinds in November at Kanombe Airport from 1974 to 199310.0NEWinds in December at Kanombe Airport from 1974 to 1993NE10.09.0N8.07.0E1 - 2 m/sN8.0E1 - 2 m/s6.06.05.04.03 - 5 m/s4.03 - 5 m/s3.02.02.01.0NW0.0SE6 - 7 m/sNW0.0SE6 - 7 m/s8 - 10 m/s8 - 10 m/sWS> 10 m/sWS> 10 m/sSWSW

75With Kigali City, it was observed that aerosol concentrations are influenced significantly by windspeed and precipitation, but no major effect of temperature and humidity was observed. As thegeneral annual trend of wind direction is from North and North-East to the South, the southern partof Kigali would expect to have highest concentration air pollution than other are in the entire city. Innew monitoring stations for air pollution monitoring/prevention have planned, their suitable sitesshould be identified in this zone.6.2.3. Effects of air pollution6.2.3.1. Health EffectsAir pollution is a commonly recognized external cost of motor vehicle use. Mobile (motor vehicle)emissions are considered more difficult to control than other emissions sources, such as electricitygeneration plants and factories, because they are numerous and dispersed, and have relativelyhigh damage costs because motor vehicles operate close to people. In many cities the air isalready so polluted that it has been causing illnesses and premature deaths among elderly peopleand children. Studies show that disease rate rises when the air pollution level increases. Airpollutants are also harmful for water and environment, for example, by causing acid precipitationand acidity of waters. Most of the ambient air-pollution in urban areas comes from the fossil fuelsindustry, motor vehicles, heating and electricity generation. In some cities the main air polluter isthe domestic heating. Many people heat their houses with firewood and cheap coal. This kind ofheating method will decrease in the future. Although, new heating methods can be even worsepolluters. Instead of carbon dioxide the emissions can include various toxic and carcinogenicchemicals, heavy metals, trace organic chemicals and fibers, photochemical pollutants, lead andcarbon monoxide, which are much more harmful to human health (UNCHS, 1996)Many studies have demonstrated that PM10 (particulate matter less than 10 microns in diameter) isassociated with a wide range of adverse health outcomes ranging from ranging from acuterespiratory symptoms to premature mortality. Given the high correlation between pollutants PM10may also serve as a surrogate measure for other pollutants including very fine particles (less than2.5 microns) and a host of traffic-related toxins (WHO, 2002b). East African Standard givespermissible limits of some common substances found in polluted air, namely sulfur dioxide, carbon

76monoxides, particulate matter, oxides of nitrogen, hydrocarbons, and lead. The standard coversboth the ambient air and emission sources for East African Community.Table 12: Ambient Air Quality Tolerance Limits in East African CommunityPollutantSulphur oxides(SO X);Oxides ofNitrogen (NO X);Time weightedAverageIndustrialareaResidential,Rural & OtherareaControlledareas***AnnualAverage*24 hours** 125 g/m 3 80 g/m 3 30 g/m 3Annual Average 0.019ppm/50g/m 3Month Average24 Hours 0.048ppm/125g/m 3One HourInstant Peak 500 g/m 3Instant Peak (10min)AnnualAverage*Test methods80 g/m 3 60 g/m 3 15 g/m 3 IS0 4221-19800.191 ppm80 g/m 3 60 g/m 3 15 g/m 3 ISO7996: 198524 hours** 150 g/m 3 80 g/m 3 30 g/m 38 hoursAnnual Average0.2 ppmMonth Average0.3 ppm24 Hours 0.4 ppmOne Hour0.8 ppmNitrogenDioxideSuspendedparticulatematter (SPM)Instant Peak1.4 ppmAnnual Average 150 g/m 3 0.05 ppm IS0 6768:1998Month Average0.08 ppm24 Hours 100 g/m 3 0.1 ppmOne Hour0.2 ppmInstant Peak0.5 ppmAnnual360 g/m 3 140 g/m 3 70 g/m 3 ISO 9835:1993Average*24 hours** 500 g/m 3 200 g/m 3 100 g/m 3IndustrialControlledareaareas***Residential,Rural & Otherareamg/KgAnnual 100 g/m 3

77PollutantRespirableparticulatematter (

Number of cases78SulfatesCarbonmonoxideNitrogenoxidesSulfurdioxideLeadLower respiratory illnessUpper respiratory illnessChest illnessRespiratory symptomsMinor RADsDays of work lossModerate or worse asthma statusMortalityHospital admissions– congestiveheart failureDecreased time to onset ofanginaRespiratory illnessMorbidity in exercisingasthmatics:Changes in pulmonary functionRespiratory symptomsMortalityHypertensionNonfatal coronary heart diseaseNonfatal strokesIntelligence quotient (IQ) lossSource: (Gwilliam and Kojima, 2004)Behavioral effectsOther hospital admissionsIncreasedresponsivenessairwayNeurobehavioral functionOther cardiovascular diseasesReproductive effectsFetal effects from maternalexposureDelinquent and antisocialbehavior in childrenInflammation of the lungOther cardiovascular effectsDevelopmental effectsDecreased pulmonaryfunctionInflammation of the lungImmunological changesRespiratory symptoms innon-asthmaticsHospital admissionsFigure 19: Respiratory Illness in Policlinic du Carrefour between 2008 and 2011450400350300250200150100500Respiratory illnesses at Polyclinic duCarrefour2008 2009 2010 2011YearLRTITuberculosisSource: Ministry of Health, 2011

Number of casesNumber of cases79Figure 20: Respiratory Illness in Kimironko Health Centre between 2002 and 2011Respiratory illnesses at Kimironko Health Centre3000025000200001500010000LRTITuberculosisPneumoniaURTI500002002 2003 2004 2005 2006 2007 2008 2009 2010 2011YearSource: Ministry of Health, 2011Figure 21: Respiratory Illness in Kanombe Military Hospital between 2008 and 2011Respiratory Illness at Kanombe Military Hospital30002500200015001000AsthmaLRTIAllergic ConjuctivitisURTIPneumonia50002008 2009 2010 2011YearSource: Ministry of Health, 2011

80Despite such challenges, mobile emission reduction efforts can be considered a qualified success.Control technologies (often spurred by regulations or incentives) have substantially reduced manypollutants’ emission rates, but this success is qualified because some pollutants are not easilyreduced by technology, emission tests often underestimate actual emission rates, emission controlsystems sometimes fail, and reduced emission rates have been partly offset by increased travel.The harmful impacts of some emissions, such as air toxics, have only recently been recognizedand so have minimal control strategies (HEI, 2007). This share is even higher in many areas werepeople congregate, such as cities, along highways and in tunnels (ORNL, 2005).6.2.3.2. Air pollution and Climate changeClimate change (also called global warming and the greenhouse effect) refers to climatic changescaused by gases (called greenhouse gases or GHGs) that increase atmospheric solar heat gain.Although some organizations argue the evidence is inconclusive or emission reduction economiccosts exceed likely benefits (e.g. Center for the Study of Carbon Dioxide and Global Change), suchgroups generally have little climatic or ecological expertise, and often represent industries thatbenefit from continued climate change emissions. Major scientific organizations consideranthropogenic (human caused) global warming a significant cost (actual damages) and risk(possibility of future damages). For example, the Intergovernmental Panel on Climate Change,concluded, “Warming of the climate system is unequivocal, as is now evident from observations ofincreases in global average air and ocean temperatures, widespread melting of snow and ice andrising global average sea level”.Local pollutants such as carbon monoxide, air toxins and particulates, tends to be concentrated invehicles and along adjacent to roadways. Air pollution costs (per ton of emission) are higher alongbusy roads, where population densities are high, and in areas where geographic and climaticconditions trap pollution and produce ozone. Emissions under conditions in which air pollutiontends to concentrate due to geographic and weather conditions (such as in valleys duringinversions) impose greater damages than the same emissions in less vulnerable locations. Jetaircraft emissions at high altitudes are believed to produce relatively large climate change impacts.The following table shows different effects of air pollution on environmental climate change.

81Table 14: Air pollution effects on environmental climate changePollutantOzone (O3)ParticulateMatter (PM)Environmental and Climate change effectsDamages vegetation by visibly injuring leaves, reducing photosynthesis, impairingreproduction and growth, and decreasing crop yields. Ozone damage to plants may alterecosystem structure, reduce biodiversity, and decrease plant uptake of CO2. Ozone is also agreenhouse gas that contributes to the warming of the atmosphere.Impairs visibility, adversely affects ecosystem processes, and damages and/or soilsstructures and property. Variable climate impacts depending on particle type. Most particlesare reflective and lead to net cooling, while some (especially black carbon) absorb energyand lead to warming. Other impacts include changing the timing and location of traditionalrainfall patternsOxides ofSulfur (SOx)Oxides ofNitrogen(NOx)CarbonMonoxide(CO)Volatile OrganicCompounds (VOCsOther ToxicAir PollutantsSource:Contributes to the acidification of soil and surface water and mercury methylation in wetlandareas. Causes injury to vegetation and local species losses in aquatic and terrestrial systems.Contributes to particle formation with associated environmental effects. Sulfate particlescontribute to the cooling of the atmosphere.Contributes to the acidification and nutrient enrichment (eutrophication, nitrogen saturation) ofsoil and surface water. Leads to biodiversity losses. Impacts levels of ozone, particles,and methane with associated environmental and climate effectsContributes to the formation of CO2 and ozone, greenhouse gases that warm theatmosphere.Contributes to ozone formation with associated environmental and climate effects.Contributes to the formation of CO2 and ozone, greenhouse gases that warm theatmosphere.Harmful to wildlife and livestock. Some toxic air pollutants accumulate in the food chain.Some toxic air pollutants contribute to ozone and particle pollution with associatedenvironmental and climate effects.7. Modeling the Air Pollution in Kigali CityAir pollution modeling is a numerical tool used to describe the causal relationship betweenemissions, meteorology, atmospheric concentrations, deposition, and other factors. Air pollutionmeasurements give important, quantitative information about ambient concentrations anddeposition, but they can only describe air quality at specific locations and times, without givingclear guidance on the identification of the causes of the air quality problem. Air pollution modeling,

82instead, can give a more complete deterministic description of the air quality problem, including ananalysis of factors and causes (emission sources, meteorological processes, and physical andchemical changes), and some guidance on the implementation of mitigation measures.Air pollution models play an important role in science, because of their capability to assess therelative importance of the relevant processes. Air pollution models are the only method thatquantifies the deterministic relationship between emissions and concentrations/depositions,including the consequences of past and future scenarios and the determination of the effectivenessof abatement strategies. This makes air pollution models indispensable in regulatory, research, andforensic application.7.1.1. Statistical modelsStatistical models are techniques based essentially on statistical data analysis of measuredambient concentrations. These models are not deterministic, in the sense that they do not establishnor simulate a cause-effect, physical relationship between emissions and ambient concentrations.One of the main statistical models is the Air Quality Forecast and Alarm Systems. This modelinclude different statistical techniques (e.g., time series analysis, spectral analysis, Kalman filters)used to forecast air pollution trends a few hours in advance for the purpose of alerting thepopulation or, for example, blocking automobile traffic.The following tables show the average and sum of different data on gases CO, SO2, NO2... thathave been collected on the station IO104-1-204 within Kigali City during the period June 2009 untilto January 2011. The data were collected on the interval of 30 min one after another. The trend ofthe evolution of gases emission can be observed according to different charts obtained.Table 15: Gases emission in Kigali City from June to-December 2009Year2009JuneStatistics CO NO NO2 NOx O3 SO2 M.PtMean 0.673491 0 0 0 50.53673829 0.582260121 0Sum 417.56439 0 0 0 31332.77774 865.8208 0July Mean 0.7272379 0 0 0 66.71198722 0.582260121 0Sum 1081.4027 0 0 0 99200.725 865.8208 0August Mean 0.6133104 0 0 0 54.33233986 0.655955608 0Sum 908.31271 0 0 0 80466.19534 971.4702556 0

83September Mean 0.5020136 0 0 0 55.56679958 0.593700353 0Sum 711.85531 0 0 0 78793.7218 841.8671004 0October Mean 0.4508038 0 0 0 39.58851915 0.42105684 0Sum 659.526 0 0 0 57918.00352 616.0061568 0November Mean 0.581346 0 0 0 27.21002473 0.188858742 0Sum 795.28185 0 0 0 37223.31382 258.3587587 0December Mean 0.619242167 2.385857664 5.12897603 7.306052802 23.02208427 0.241132951 0Sum 917.71689 3535.841058 7601.142476 10827.57025 34118.72888 357.359033 0Total 5491.65985 3535.841058 7601.142476 10827.57025 419053.4661 4776.7029 0Table 16: Gases emission in Kigali City in 2010Year2010Statistics CO NO NO 2 NO x O 3 SO 2 M.Pt.January Mean 0.6277503 0.704611 1.567012 2.12927 37.61930364 0.556157422 0Sum 930.95375 1044.938 2323.879 3157.707 55789.4273 824.7814574 0February Mean 0.5821512 1.06E-05 0 0 31.80741845 0.644351382 0Sum 780.08265 0.014211 0 0 42621.94072 863.4308514 0March Mean 0.5809882 0 0 0 25.80570027 0.501789766 0Sum 846.49979 0 0 0 37598.9053 731.1076898 0April Mean 0.5598754 0 0 0 20.42862934 0.339776401 0Sum 800.06198 0 0 0 29192.51133 485.5404764 0May Mean 0.6674135 0 0 0 20.54263245 0.484662272 0Sum 987.77191 0 0 0 30403.09603 717.3001623 0June Mean 0.7855863 0.303926 0 0.232692 39.19606571 0.283553125 0Sum 981.19729 379.6039 0 290.6327 48955.88607 354.1578531 0July Mean 0.7883689 0 0 0 52.41636318 0.508791119 0Sum 1092.6793 0 0 0 72649.07936 705.1844911 0August Mean 0.8260785 0 0 0 55.61853351 0.227800068 0

84Sum 1220.944 0 0 0 82204.19253 336.6885001 0September Mean 0.7905891 0 0 0 47.01160292 0.087753343 0Sum 1136.0765 0 0 0 67555.6734 126.1015533 0October Mean 0.7373611 0 0 0 39.35778524 0.331660528 0Sum 1089.8198 0 0 0 58170.80659 490.1942605 0November Mean 0.7621111 0 0 0 32.66663184 0.079563255 0Sum 1073.0524 0 0 0 45994.61763 112.0250633 0December Mean 0.8071351 0 0 0 36.33897431 0.174808519 0Sum 1194.5599 0 0 0 53781.68197 258.7166085 0Total 12133.69927 379.6039 0 290.6327 624917.8182 6005.228967Table 17: Gases emission in Kigali City in January 2011Year2011Statistics CO NO NO2 NOx O3 SO2 M.Pt.January Mean 0.7947499 0 0 0 39.13866567 0.1872394 0Sum 1192.9196 0 0 058747.13717281.0463394 0Before 9FebruaryMean 0.8203964 0 0 0 35.1143131 0.006589286 0Sum 276.4736 0 0 0 11833.52351 2.220589286 0Total 1469.3932 0 0 0 70580.66068 283.2669287 07.2. Air pollution trends in Kigali City7.2.1. Suspended particulate matterAtmospheric particulate matter is defined to be any dispersed matter, solid or liquid, smaller than,500 μm. Under various conditions of their generation, they are also called by other names such asdust, fume, smoke and mist. Dust usually refers to the particles in the range of 1 to 200 μm size.Fume is very fine solid or liquid particles arising from chemical reactions or condensation of gases.Smoke refers to finely divided particles resulting from incomplete combustion of substances suchas coal, petroleum, etc.

85Particles in the range of 0.1μm to 10μm are of, most interest from health viewpoint. Particulatematter of less then 10μm size (PM10) is classified as respirable dust. Larger particles that enter therespiratory system are trapped by hairs and lining of nose or can be captured by mucus in upperrespiratory tract and worked back to the throat by cilia and removed by spitting. Particles between0.5 and 10 μm, called thoracic particles, penetrate to the lungs and are deposited there. Theseparticles by themselves and or by carrying other air pollutants adsorbed on them may cause thegreatest harm. Elevated particulate concentrations in the atmosphere, in the range of 400 μg/m 3and above especially in conjunction with oxides of sulphur have been linked to respiratoryinfections, bronchitis, asthma, pneumonia and the like. Many carbonaceous particles, especiallythose containing polycyclic aromatic hydrocarbons (PAH) are suspected carcinogens (UNEP,2004).Within Kigali City, a seasonal variation was found as consistently higher dust load was found in thedry season which might possibly be attributed to the prevailed meteorological conditions such aslow precipitation and wind speed. Comparing the aerosol particles concentration sampled duringweekend-days in Kigali City, the results showed that the concentration of particle matter was higherin dry season than in the rainy season. However, the weekday measurements show the oppositetrend. This might be related to the wind direction and high wind speed which might be observedduring the rainy season and low precipitation observed during the dry season; it was high asexpected taking into account that the soil dust was still produced in the city in dry season, as wellas the presence of a number of old cars and motor vehicles on the streets (Ingabire, 2009).7.2.2. Sulphur dioxideSulphur dioxide when released in the atmosphere can also convert to SO2, which leads toproduction of sulphuric acid. When SO2 is inhaled it is likely to be absorbed in moist passages ofrespiratory tract. When it is entrained in an aerosol, however, it may reach far deeper into thelungs. The adverse health effects of SO2 can be summarized as the deterioration in healthbronchitis patients, increased incidence of the cardiorespiratory diseases; and increased hospitalityadmission and as well as augmented cardio-vascular morbidity. At the same, the sulphur dioxidecan damage the vegetation and cause corrosion. Airborne sulfates reduce visibility. It is also thecause of acid rain in some countries.

SO2 (ppb)14-Jun-0921-Jun-0928-Jun-095-Jul-0912-Jul-0919-Jul-0926-Jul-092-Aug-099-Aug-0916-Aug-0923-Aug-0930-Aug-096-Sep-0913-Sep-0920-Sep-0927-Sep-094-Oct-0911-Oct-0918-Oct-0925-Oct-091-Nov-098-Nov-0915-Nov-0922-Nov-0929-Nov-096-Dec-0913-Dec-0920-Dec-0927-Dec-093-Jan-1010-Jan-1017-Jan-1024-Jan-1031-Jan-107-Feb-1014-Feb-1021-Feb-1028-Feb-107-Mar-1014-Mar-1021-Mar-1028-Mar-104-Apr-1011-Apr-1018-Apr-1025-Apr-102-May-109-May-1016-May-1023-May-1030-May-106-Jun-1013-Jun-1020-Jun-1027-Jun-104-Jul-1011-Jul-1018-Jul-1025-Jul-101-Aug-108-Aug-1015-Aug-1022-Aug-1029-Aug-105-Sep-1012-Sep-1019-Sep-1086Figure 22: Long term SO 2 Concentration within Kigali City20151050-5Source: Kigali Institute of Science and Technology, 2010For the year 2009 and 2010, it is clear that the long-term concentration of sulphur dioxide in KigaliCity using the only one available air quality monitoring system which is located at Kigali Institute ofScience and Technology reached its peak in dry seasons (August 2009, January and July 2010).Source:

Conentration in in µg/m387Source:Another <strong>study</strong> on of atmospheric aerosols in Kigali City using the sample sites revealed thefollowing results.Figure 23: Concentration of SO 2- 4 and SO 2 in sample taken in Kigali CityThe SO4 2- concentration was higher at the 4 thConcentration of SO 4 and SO 2 in sample taken in Kigali City75.94654.6743.58SO42-32.47SO22.272.1121.741.371 0.560.440.57 0.550.410.5601 2 3 4 5 6 7Numner of samplesSource: (Ingabire, 2009)sample (weekend dry) compared to othersamples. Among the measured elements, SO4 2-was highest in concentration. The maximumconcentration of SO4 2- was 2.47 µg/m 3 collectedduring weekend. The minimum concentrationSO4 2- was 0.41 µg/m 3 collected during 24 hoursampling. The highest concentration of SO2 was5.94 µg/m 3 (Ingabire, 2009).Based on the above results, it can be concluded that the sulphur dioxide released in theatmosphere of Kigali City is low when compared to the accepted annually average recommended

13-Dec-0920-Dec-0927-Dec-093-Jan-1010-Jan-1017-Jan-1024-Jan-1031-Jan-107-Feb-1014-Feb-1021-Feb-1028-Feb-107-Mar-1014-Mar-1021-Mar-1028-Mar-104-Apr-1011-Apr-1018-Apr-1025-Apr-102-May-109-May-1016-May-1023-May-1030-May-106-Jun-1013-Jun-1020-Jun-1027-Jun-104-Jul-1011-Jul-1018-Jul-1025-Jul-101-Aug-108-Aug-10NO (ppb)O3 (ppb)88by East African Standard for some common substances found in polluted air ( 80 g/m 3 forindustrial areas, 60 g/m 3 for residential areas; a 15 g/m 3 controlled areas). But during the dryseasons, the measures taken at KIST air quality monitoring are beyond the permissible limits.7.2.3. Nitrogen oxidesAlmost all NOx emissions are in the form of NO, which has no known adverse health effects in theconcentrations found in atmosphere. However, NO can be oxidized to NO2 in the atmosphere,which in turn may give rise to secondary pollutants, which are injurious. NO2 may also lead toformation of HNO3, which is washed out of the atmosphere as acid rain. From 2009 to 2010, thelong term Nitrogen Dioxide concentration in Kigali City reached the highest level in short dryseason of January 2010 and in long dry season of July-August 2010.Figure 24: Long term NO-O3 Concentration within Kigali City3012010025802060401520100-205-400-60Source: Kigali Institute of Science and Technology, 2009The average concentration was estimate between 15 and 20 g/m 3 while the permissible limitvalue of proposed by the East African Standard for some common substances found in polluted airis 150 g/m 3. Therefore, it can be conclude that nitrogen dioxide concentration level is the range ofaccepted limit for air quality control and monitoring guidelines.

13-Dec-0920-Dec-0927-Dec-093-Jan-1010-Jan-1017-Jan-1024-Jan-1031-Jan-107-Feb-1014-Feb-1021-Feb-1028-Feb-107-Mar-1014-Mar-1021-Mar-1028-Mar-104-Apr-1011-Apr-1018-Apr-1025-Apr-102-May-109-May-1016-May-1023-May-1030-May-106-Jun-1013-Jun-1020-Jun-1027-Jun-104-Jul-1011-Jul-1018-Jul-1025-Jul-101-Aug-108-Aug-10NO2 (ppb)O3 (ppb)89Figure 25: Diagram of long term NO2-O3 Concentration within Kigali City30120251008020601540102050-200-40-5-60Source: Kigali Institute of Science and Technology, 20107.2.4. Carbon monoxideMost of the CO emissions are from transportation sector. Peak concentrations occur at street levelin busy urban centers particularly when there is no atmospheric mixing as it happens during winterseason. Carbon monoxide interferes with blood's ability to carry oxygen. With the blood streamcarrying less oxygen, brain function is affected and heart rate increases in an attempt to offset theoxygen deficit. Breathing between 20 to 35 ppm CO in air for 4 hours results in impairment of timerelated response. Individuals with heart condition may experience chest pain. Exposure to 100ppmconcentration would result in dizziness.

CO (ppm)14-Jun-0921-Jun-0928-Jun-095-Jul-0912-Jul-0919-Jul-0926-Jul-092-Aug-099-Aug-0916-Aug-0923-Aug-0930-Aug-096-Sep-0913-Sep-0920-Sep-0927-Sep-094-Oct-0911-Oct-0918-Oct-0925-Oct-091-Nov-098-Nov-0915-Nov-0922-Nov-0929-Nov-096-Dec-0913-Dec-0920-Dec-0927-Dec-093-Jan-1010-Jan-1017-Jan-1024-Jan-1031-Jan-107-Feb-1014-Feb-1021-Feb-1028-Feb-107-Mar-1014-Mar-1021-Mar-1028-Mar-104-Apr-1011-Apr-1018-Apr-1025-Apr-102-May-109-May-1016-May-1023-May-1030-May-106-Jun-1013-Jun-1020-Jun-1027-Jun-104-Jul-1011-Jul-1018-Jul-1025-Jul-101-Aug-108-Aug-1090Figure 26: Long term C0 Concentration within Kigali City76543210Source: Kigali Institute of Science and Technology, 2010

CO (ppm)O 3 (ppb)91Figure 27: Long term CO-O3 Concentration within Kigali City4.516041403.512032.521.510080601400.5200027-May-0916-Jun-096-Jul-0926-Jul-0915-Aug-094-Sep-0924-Sep-0914-Oct-093-Nov-0923-Nov-09TimeSource: Kigali Institute of Science and Technology, 2009It is very important to monitor the air pollution continuously and constantly. That is the only way toanalyze the situation of air pollution in an appropriate manner. And the machine at KIST is the onlyavailable one in Rwanda to keep this valuable data.7.2.5. Ozone (O3)As already mentioned, Ozone gas is not usually emitted directly into the air, but at ground-level iscreated by a chemical reaction between oxides of nitrogen (NOx) and volatile organic compounds(VOC) in the presence of sunlight. Motor vehicle exhaust and industrial emissions, gasoline vapors,and chemical solvents as well as natural sources emit NOx and VOC that help form ozone. Unlikethe protective layer of ozone present in the upper atmosphere, ozone produced at ground level canhave a serious health effects on people who suffer from lung diseases asthma or emphysema.Within Kigali City, the Diurnal Ozone (O3) concentration in August 2009 using the single monitoringsystem located at Kigali Institute of Science and Technology revealed a higher concentration ofOzone (O3) in atmosphere in the morning between 6:00-12:00 AM.

Ozone (ppb)92Figure 28: Diurnal Ozone (O3) concentration in August 2009 within Kigali City1201008060402002009/8/1 12:002009/8/1 18:002009/8/2 0:002009/8/2 6:002009/8/2 12:002009/8/2 18:002009/8/3 0:002009/8/3 6:002009/8/3 12:002009/8/3 18:002009/8/4 0:00Source: Kigali Institute of Science and Technology, 2009Thanks to the KIST newly installed air pollutants monitoring machine, now it is known that theexact situation of air pollution of Kigali City from 2009 is known. The below is the data set onground-level ozone measured on KIST campus. The following figures show the general trends ofozone between 2009 and February 2011.

14-Jun-0921-Jun-0928-Jun-095-Jul-0912-Jul-0919-Jul-0926-Jul-092-Aug-099-Aug-0916-Aug-0923-Aug-0930-Aug-096-Sep-0913-Sep-0920-Sep-0927-Sep-094-Oct-0911-Oct-0918-Oct-0925-Oct-091-Nov-098-Nov-0915-Nov-0922-Nov-0929-Nov-096-Dec-0913-Dec-0920-Dec-0927-Dec-093-Jan-1010-Jan-1017-Jan-1024-Jan-1031-Jan-107-Feb-1014-Feb-1021-Feb-1028-Feb-107-Mar-1014-Mar-1021-Mar-1028-Mar-104-Apr-1011-Apr-1018-Apr-1025-Apr-102-May-109-May-1016-May-1023-May-1030-May-106-Jun-1013-Jun-1020-Jun-1027-Jun-104-Jul-1011-Jul-1018-Jul-1025-Jul-101-Aug-108-Aug-1015-Aug-1022-Aug-10Ozone (ppb)93Figure 29: Long-term Ozone (O 3 ) concentration within Kigali City160140120100806040200Source: Kigali Institute of Science and Technology, 2010The blue line illustrates 0.075ppm, the level of United States-Environmental Protection Agency(US-EPA) environmental standard of ground-level ozone. In short, we can summarize that In KigaliCity, especially during the dry season, the concentration of ground-level ozone is already beyondthe major environmental standards, and the problem of air pollution is already at present (Mito,2010). When considering the scale of industrial activities in Kigali, we can assume that the primarysource of this pollution is motor vehicle exhaust especially caused by bad maintenance of itsemission control. However, the weather patterns play an important role in establishing conditionsconducive to ozone formation and accumulation, as well as conditions terminating ozone episodes.Many scientists agreed that meteorological conditions determine whether ozone and/or itsprecursors will be retained locally, (stagnant air masses) or will be transported downwind. Hightemperatures enhance the rate of ozone formation. Some processes such as moving high pressuresystems, can disperse ozone and transport it to or from higher layers in the atmosphere.As implications to human health in Kigali City, people with lung disease, children, older adults, andpeople who are active can be affected when ozone levels are unhealthy like it is the case in Kigali.Numerous scientific studies have linked ground-level ozone exposure to a variety of problems,

94including: airway irritation, coughing, and pain when taking a deep breath; wheezing and breathingdifficulties during exercise or outdoor activities; inflammation, which is much like a sunburn on theskin; aggravation of asthma and increased susceptibility to respiratory illnesses like pneumoniaand bronchitis; and, permanent lung damage with repeated exposures (US-EPA, 2011).Therefore, comprehensive measures must be taken to tackle with this issue. For example,installation of an inspection system on motor vehicle exhaust, establishment of regulations on caremission and air pollution environmental standards, tax incentive introduction for importation ofenvironmentally friendly cars, reinforcement of air pollution monitoring system would be essential.Although taking the above measures would be very costly more air pollution monitoring systems inKigali in order to monitor the air pollution properly), we should start something now to preventsevere consequences (Mito, 2010).7.2.6. Lead (Pb)Lead released from motor vehicle exhaust may affect human populations by direct inhalation, inwhich case people living nearest to highways are at greatest risk. Lead can be ingested also after itis deposited on to foodstuffs. Measurements made in exposed communities indicate that leadconcentration of 1μg/m 3 in ambient air results in an increase of about 1-2 μg per decilitre (μg/dl) inblood. Lead poisoning can cause destructive behavioral changes, learning disabilities and

95permanent brain damage. Children and pregnant women are at greatest risk. Blood levels of 50–60μg/dl are associated with neurobehavioral changes in children. Ingabire (2009), concluded that thePb level in the aerosols in Kigali City is below the World Health Organization (WHO, 0.5-1.5µg/m 3 )and East African Community recommended levels (0.5-1.0µg/m 3 ). According to her, the air qualityin Rwanda is still at a favourable level as compared to most countries in the world, but theindustrial activities and traffic density continue to grow.7.3. Strategies for reducing air pollution7.3.1. Strategic approachesThe development of a strategy involves the selection of a coherent set of measures which, takentogether, will reduce the emissions of transport pollutants. These measures can be technologyoriented,targeting the vehicles and fuels used and maintenance practices within the sector, or theycan be behavioral, seeking to reduce (or prevent increases in) the amount of activity of the mostpolluting vehicles. They may also focus on systemic aspects of the transport system–ways in whichthe transport network influences either the aggregate amount of vehicle use or the emissionsintensity of individual vehicles. Emission control strategies for the transport sector should bedetermined in the broader context of improving outdoor air quality in an urban region. This involvesimportant economic technical analysis in the context of air quality management programmers.Different programmers such as the World Bank’s Air Quality Management System are useful inidentifying the most efficient use of scarce resources to address an air quality problem.However, the process of carrying out such an assessment tends to be quantitative; interventionswhose costs or benefits are not easily quantified tend to be discounted. The assessment also tendsto be static in its analytical approach, not taking into account potential changes in demand overtime. Consequently, it often does not take into account systemic changes that can influence thischange in demand. These limitations should be borne in mind in devising an effective emissionsstrategy with regard to transport.

967.3.1.1. Technical strategiesTechnical approaches seek to reduce the emissions produced by road vehicles using the transportsystem by intervening with the vehicles being used and the fuels they are burning. By definition,these approaches address per unit emissions rather than the amount of activity causing theemissions. An exclusively technological approach may be insufficient to address the growth inemissions, for a number of reasons. First, growth in activity continuously puts pressure ontechnology gains. Secondly, technological improvements can exacerbate the growth in activitythrough the much-debated “rebound” effect. Thirdly, an exclusively technological approach toaddressing the problem of emissions may result in significant over-investment in technologycompared with a socially optimum solution (that is, one which would result if a pure tax on missionswere implemented).7.3.1.2. Vehicle technologyChanging or improving technology: Technological improvements to vehicles are limited by localcapacity to absorb the technology, which includes both turnover rates and capabilities for servicingand maintenance, and by the availability of appropriate fuel for the technology. Consequently,vehicle technology strategies need to be developed in response to particular local circumstancesand in concert with fuel strategies. These strategies may involve improvements in conventionaltechnologies already in widespread use–such as improvements to engine and fuel systems, betteror more widespread use of gasoline or diesel exhaust after treatments, changes and improvementsto transmission systems (to increase efficiency and reduce CO2 emissions), treatment for fuelsupply and crankcase systems (to reduce evaporative emissions), or improvements to overallvehicle or tyre design to reduce friction. Technological improvements might also involve theadoption and use of alternative fuel or alternative propulsion vehicles. In developing countries, themost commonly discussed alternative vehicle strategies include compressed natural gas (CNG),liquefied petroleum gas (LPG), alcohol-based fuels, and electric propulsion or hybrid-electricvehicles in certain applications. Other alternative fuels showing potential long-term promise in thetransport sector include hydrogen fuel cells and various synthetic fuels for use in compressionignitionengines.

97Rate of change of technology in the vehicle fleet: An extensive review of appropriatetechnologies in the emissions-reduction literature and at conferences can often mask theunderlying importance of the rate of change of technology. Over the short and medium term, therate of change is more important than the technology itself for reducing transport emissions,particularly for fleets where baseline emissions control mechanisms are minimal or non-existent.In assessing any technology, therefore, the analysis of technological options needs to movebeyond a narrow assessment of the relative emissions and energy consumption capabilities ofeach technology; rather, the analysis should focus on how rapidly the different technologies can bedeployed and widely used in the fleet. The rate of change of technology can be influenced byencouraging vehicle turnover, ideally through well-designed adjustments to the fiscal regime underwhich cars are taxed over their lifetimes, or through vehicle retrofitting programmers’, which allowolder vehicles to benefit from more recent technology. The organizational and technical logistics ofretrofit programmes are substantially different, depending on whether gasoline or diesel vehiclesand individual or fleet owners are targeted.Vehicle maintenance: Vehicle maintenance is a crucial part of any technical strategy to reduceper kilometer emissions of pollutants, both because the proportion of in-use vehicles is substantialcompared with new vehicles in any given year, and because of the vigilance required to ensurethat exhaust after-treatment technology is well maintained and remains functional. The principallogistical problem is designing cost-effective measures that ensure that the vehicles most in needof maintenance actually receive it. Programmes tend to be most cost-effective when they target“gross-emitters”, those 20 per cent of vehicles that tend to produce 80 per cent of the pollution,according to the rule of thumb that applies to cities in developed as well as developing countries.Effective strategies focusing on vehicle maintenance have three key elements: Emissions testing, which provides a mechanism to identify vehicles that are notperforming according to regulations; Driver and fleet manager education and training, which is important in facilitating theacceptance of emissions testing components, such as inspection and maintenanceprogrammes, and because such training can specifically target high-kilometre drivers;

98 A programme of ongoing product liability, for either manufacturers or importers, whichmight also help to ensure better maintenance by creating a market incentive for suppliersto follow up on their products.7.3.1.3. Fuel technologyImprovements to the specifications of fuels are as important as improvements to vehicles. Fuelimprovements can affect emissions in three ways. First, changes to fuel content can directly bringabout a reduction in emissions of certain pollutants, such as lead, sulphates, oxides of sulphur(SOx), or VOCs. Unlike changes to vehicle technology, the effects of these types of fuel contentchanges are immediate. Secondly, changes in fuel content can facilitate the use of certain exhaustafter-treatment technologies–particularly those using platinum -based catalysts–which would nothave been usable before. Thirdly, the costs of these improvements are passed on to the consumerbut, unlike the costs for technical improvements to vehicles, these costs are passed on as variablerather than fixed costs. This is compatible with a strategy aimed at variabilizing costs as much aspossible.7.3.1.4. Systemic strategiesSystemic approaches to air quality focus on the transport network, seeking to adjust drivingconditions so as to enable vehicles to operate in the least emissions-intensive manner possible.Such a goal can involve increasing average speeds to an optimal level (ordinarily between 65 and90 kilometers per hour for most pollutants, including CO2), or “smoothing” flow, so as to reduce thevariability of speeds and eliminate the need to accelerate or decelerate. In practice, smoothing flowand increasing average speeds are often inseparable practical outcomes of the same engineeringinterventions. Increasing average speeds on a road network, however, is also associated with thephenomenon of induced traffic, that is, an increase in motor vehicle use occurring in response toan improvement in motor vehicle traffic conditions. Induced traffic means that, at the very least, theemissions-rate reductions from smoother flow need to be weighed against an increase in overallemissions from more traffic. This balancing suggests two potentially different systemic strategiesfor air quality purposes: smoothing flow on the one hand, and restraining traffic on the other hand.In this context, the market, through congestion pricing, would be more able to “choose” betweenthese competing and conflicting strategic approaches than could any engineering assessment.

997.3.1.5. Role of international communityThe international community, through various arms of the United Nations, the multilateraldevelopment banks, and bilateral aid agencies, has helped cities in developing countries toaddress transportation emissions through a number of different programmes. This aid has beensuccessful to a varying extent, although not always cohesive, and not necessarily comprehensive.Much of the substantive work in regions with particularly alarming air quality has focused onassistance with assessment and economic evaluation of the problem, including prioritization ofinvestments for air quality mitigation. A number of crucial needs, however, are still under-served bythe international community. In general, these needs involve institutional development, integrationof environmental criteria into transport and urban planning, and support for long-run assessmentsof alternative investment scenarios.8. Existing Policy Framework8.1. Air pollution policies and regulations in RwandaLike most other countries in the world, Rwanda is dependent on oil products for a wide range ofactivities, notably transport, electricity generation, industry, cooking and lighting (MININFRA, 2004).Oil-based energy generation not only is it an expensive exercise, but one of the strongenvironmentally unfriendly undertakings owing to its carbon dioxide emissions into the atmosphere.As we all know this contributes strongly to global climate change (http://www.newtimes.co.rw).In Rwanda, urban air pollution resulting from dust particles and vehicle emission is increasinglygrowing. During the dry season, there is a marked increase in air borne diseases due to dustparticles emission especially in urban areas (REMA, 2009). Poorly maintained roads, old mopeds,motorcycles and vehicles cause an increasing concentration of different air pollutants (Henninger,2009). In the recent years the number of vehicles has tremendously increased especially in KigaliCity, where also the number of people rapidly increases. The increase in number of vehicle inKigali City implies the increase in exhausts emitted by these and subsequently increase in risksassociated with the emissions while documented information on this issue is still lacking (REMA,2009). It was found that air pollution in Kigali has reached an incredible level as the concentrationof some air pollutants of is far above those recommended by the World Health Organization(WHO).

100Particularly, the particle matter concentration in the air suggests that air pollution creates a greatrisk to the inhabitants’ health. The meteorological conditions in Kigali City further contribute to thishealth risk due to an expected higher stability of the urban atmosphere. This results in a lowertransportation and dispersion of polluted air, hence causing accumulation of the airborne pollutionswithin the small valleys and the residential areas respectively (Henninger, 2009). Apart from thetraffic emissions, there is also another source of air pollution representative for developing world:the usage of simple stoves and open fireplaces. Burning wood for domestic energy, cooking andhousehold everyday jobs produce a lot of emission, indoor and outdoor (Han and Naeher, 2006) inKigali City.Despite this concern, there has been so far no comprehensive <strong>study</strong> that relates diseases such aslung cancer with air pollution caused by emissions from vehicles. The pollution levels and possiblecauses of air pollution with possible measures in case of high levels of pollution is also not wellmonitored nor known in Kigali City (Henninger, 2009). The situation is complicated by the lack ofair quality standards that would serve as a basis to enforce certain measures that would help tocontrol emissions. This is particularly challenging since it calls for heavy investments in physicalinfrastructure and clear policy framework to control air pollution in Kigali City.8.2. Multilateral agreements and international conventionsFrom International perspective, Rwanda has already signed the Multilateral Agreements includingthe Kyoto Protocol, United Nations Framework Convention on Climate Change (UNFCCC) and theVienna Convention. The Kyoto Protocol to the United Nations Framework Convention on ClimateChange strengthens the international response to climate change, and promotes the Convention'sultimate objective of preventing "dangerous anthropogenic [human-made] interference with theclimate system"; The United Nations Framework Convention on Climate Change (UNFCCC)refers to the international agreement that targets industrial and other emissions of greenhousegases such as carbon dioxide. The UNFCC is the centerpiece of global efforts to combat globalwarming. Initially adopted in 1992 at the Rio de Janeiro "Earth Summit"(http://www.un.org/geninfo/bp/enviro.html), the Convention entered into force on March 21, 1994.The ultimate objective of the UNFCC is the "stabilization of greenhouse gas concentrations in theatmosphere at a level that would prevent dangerous anthropogenic (human-made) interference

101with the climate system. Such a level should be achieved within a time-frame sufficient to allowecosystems to adapt naturally to climate change, to ensure that food production is not threatenedand to enable economic development to proceed in a sustainable manner. The ViennaConvention refers to the United Nations Environment Program’s (UNEP) Convention on theProtection of the Ozone Layer, adopted by the governments of the world in 1985. Through theVienna Convention on the Protection of the Ozone Layer, governments committed themselves toprotect the ozone layer, to cooperate in scientific research, and to improve the understanding ofatmospheric processes Under the Convention, nations agree to take "appropriate measures…toprotect human health and the environment against adverse effects resulting or likely to result fromhuman activities which modify or are likely to modify the Ozone Layer." The measures areunspecified. There is no mention of any substances that might harm the ozone; CFCs appeartowards the end of the annex to the treaty, where they are mentioned as chemicals that should bemonitored.8.3. Local policies, laws, programs and strategiesWith the rapid urban development of Kigali City and the resulting increase in air pollution, theRwanda’s Government is locally acting by developing long term orientations, policies, laws,programs and strategies to control and reduce air pollution and the associated human health risks.For example, the Rwanda’s Energy Policy of 2004 states that the petroleum operations should beundertaken by ensuring highly established standards for environmental impact assessments andenvironmental management plans will be mandatory (MININFRA, 2004). The Article 81 of theRwanda organic law on modalities of protection, conservation and promotion of the environmentdoes not allow any activity that may damaging the quality of air, non authorised bush burning; andas well as the smoking in public and in any other place where many people meet. It is alsoprohibited to release into the atmosphere poisonous gases, smoke, waste, soot, dust and anyother chemical substances in an illegal manner (Government of Rwanda, 2005). Rwanda’s effortsin reducing its reliance on oil are supported through the development of Clean DevelopmentMechanism Projects – which means, for every certified reduction of emissions of carbon dioxide,we gain on what is referred to as carbon credits and subsequently generate revenues through thesale of those carbon credits on the global market (MININFRA, 2008) .

102Recently, Rwanda is supporting the efforts of the international community which contribute to thereduction and elimination of the consumption and production of substances likely to deplete theozone. In this regard, REMA has undertaken some of the following activities: preparation incollaboration with RBS of standards on air quality; guidance on pollution control and promotion ofthe Cleaner Production Programme. Cleaner Production is applied to the entire production cycle toincrease productivity by ensuring a more efficient use of raw materials, to promote betterenvironmental performance through reduction at source of emissions. More than 10 Rwandanindustries participate in Cleaner Production. The recent publication of air quality emissions by theRwanda Bureau of Standards will play a key role in the emissions control and enforcement of thelaws (Government of Rwanda, 2010). In transport sector, the Police’s Motor Vehicle InspectionCentre (MIC), has recently introduced engine gas emission inspection to the already existing testsit carries out. The new inspection will contribute to the country’s environmental protection efforts,since vehicles that emit toxic gases will not be allowed to operate (RNP, 2011).8.4. Role of public transport planningIn Kigali City some problem of air pollution are exaggerated by traffic management system. Sometraffic calming methods such as multiple speed reducing humps are found on certain roads toreduce the speeds of vehicles especially in areas where there are tight corners and steepgradients. However, these are improperly designed and in many cases, ill-maintained. With theincreases in private cars, vehicles are beginning to cause congestion at some important junctionsand along the major roads. This is compounded by improper design of roads and junctions, as canbe seen in the case of the six-legged Centre Ville Roundabout where traffic congestion occurspartly due to the fact that the approaches are too close of each other.With the economic growth that will bring about new wealth to the people, it is anticipated that carownership will escalate in the future as it is the common aspiration of the people in Rwanda to owna car. The increase in car ownership and car usage is expected to put a strain on the road networkin the future, if left unchecked. This will also put a strain to the government in getting funding to addmore road space and construct new roads to cater to the ever-increasing car population on theroad. To avoid the need to keep adding road space within the City to cater to the travel demand infuture, it is the aim of the Master Plan to put in place an efficient and convenient public transport

103system within Kigali City to ensure that public transport will remain as the preferred mode oftransport in the future and maintain a modal split of 70:30 for public transport versus private cars.To achieve this, it is important to improve public transport facilities and services to make publictransport an efficient and convenient mode of transport.To achieve this objective, the following strategies are adopted in the planning of public transport inNyarugenge District: develop an integrated and cost effective public transport system offeringregional and local connectivity; develop bus interchanges within townships which offer regional andlocal connectivity; Increase the carrying capacity of public buses by phasing out mini-bus taxis andintroducing buses with higher capacity such as the long buses or articulated buses; and creatededicated bus lanes along major roads to ensure smooth flowing of buses.In the present global trend towards sustainable developments, green transport which includewalking and cycling will be promoted in the development of Kigali City. To encourage people tocontinue to cycle and walk for short distance commuting, it is important to create a conduciveenvironment for walking and cycling within the City. To this end, the following strategies areadopted in the master plan: Develop a green connector network linking all green areas within theCity; Provide dedicated pedestrian walkways and cycling paths along roads as well asneighborhoods and housing estates; and Provide facilities such as bicycle shed adjacent to businterchanges / terminals within the City where it is possible (MININFRA, 2009a).9. Towards urban air pollution policy in RwandaWhereas pollution of the air in Rwanda will imperil public health and welfare, create public orprivate nuisances, be harmful to wildlife and impair domestic, agricultural, industrial, recreationaland other beneficial uses; it is hereby declared to be the policy and purpose of this policy on airpollution to enable the government to prevent, reduce and eliminate air pollution; to preserve andenhance the air; to plan the development, use, reclamation, preservation and enhancement of theair, to preserve and exercise the primary responsibilities and rights of government; to retain for thegovernment the control over its air, and to secure cooperation between different entities in carryingout their objectives.

104Clean air can only be achieved through a sustainable mechanisms such as car emission inspectionand control; oil quality inspection and control but also by providing some incentive measuresaiming at encouraging people to use and purchase what is known as “Green Cars” which have alow impact on the environment.Basing on the organic law n° 04/2005 of 08/04/2005 determining the modalities of protection,conservation and promotion of environment in Rwanda, the government has the primary obligationto protect the environment. The environment in Rwanda constitutes a common national heritage,the reason why the government has to provide a basis (or standards) for protecting public healthfrom adverse effects of environmental pollutants, and for eliminating or reducing to a minimum,contaminants that are known or likely to be hazardous to human health and well-being.Nevertheless, the objective of monitoring of the air pollution in Rwanda cannot be achievedeffectively by public and private entities that are acting individually. In particular, as different entitiescontribute to the air pollution; they should have collective responsibility to work hand in hand insolving the problems caused by the air pollution.The government of Rwanda created different institutions like RURA; RBS which, without aimingdirectly at the protection of environment, their respective missions have indirectly impact on theenvironment protection. For instance, RBS is the only body with powers to define nationalstandards, with the main responsibility of defining national standards, coordinating all the activitiesin relation to standards, ensuring their application and metrology observance in the country,providing reference metrology standard, controlling its observance and ensuring its disseminationall over the country.9.1.1. Vision of air quality monitoring policyEven though, every person has the duty to protect, conserve and promote environment, the Statehas the principal responsibility of protecting, conserving and promoting the environment. Therefore,on one side, not only every person in Rwanda has a fundamental right to live in a healthy andbalanced environment, but also he or she has the obligation to contribute individually or collectivelyto the conservation of clean air. On the other side, the establishment of national policy of

105protection, conservation and promotion of the natural air is within the responsibility of theGovernment of Rwanda. It develops strategies, plans and national program aiming at ensuring theconservation and effective use of clean air.9.1.2. Policy statementThe main purpose of air quality management in Rwanda would be to protect public health and theenvironment from the adverse effects of air pollution. Adequate air quality management strategiesencompass many activities, including risk assessment, air quality and emission standard setting,monitoring and enforcement, implementation of control measures, and risk communication. Theuse of air quality standards, however, has become the cornerstone of air quality management,whose roles, adopted and enforced by regulatory authorities, is to define the level of acceptable airpollution for a country or a region. The primary aim of this policy presented here is to provide aregulatory framework for protecting public health from the effects of air pollution.In Rwanda, even though we have different institutions dealing directly or indirectly with theprotection of the environment, there are currently no specific legislations regulating themanagement of the ambient air. However, there are legislations already developed and othersbeing developed concerning the management of the environment in general such as Organic LawN° 04/2005 of 08/04/2005 determining the modalities of protection, conservation and promotion ofenvironment in Rwanda and Law N° 39/2001 of 13/09/2001 establishing an agency for theregulation of certain public utilities that will handle the removal of waste products from residential orbusiness premises. The regulatory authority and the Ministry in charge of Environment have setdifferent quality standards in some domain but without clearly establishing clear and specificstandards of ambient air.It is in this regards, the foundation of this policy is to clearly underscore the need for theexpeditious application of the law in the promotion of national commitment by properly handling theproblem resulting from the air pollution in the country. It aims to provide the necessary legal andregulatory certitude for all stakeholders in the air protection and prevention.

1069.1.3. Policy objectivesWith regards to air environment standards, it has always been the Government's key mission andpolicy objective to improve our air quality, thereby enhancing protection of public health. The airquality policies define minimum standards for the protection of health and the environments thatare to be met everywhere. The main two aims of the air quality policy are: (i)To “define andestablish objectives for ambient air quality in the community designed to avoid, prevent or reduceharmful effects on human health and the environment as a whole”; and (ii) to “maintain air qualitywhere it is good and to improve it in other cases”.9.1.4. Core principles FindingsThe Government finds that:i. Predominant part of the Nation’s population is located in its rapidly expanding urban areas,which generally cross the boundary lines of local jurisdictions and often extend rural areas;ii. Growth in the amount and complexity of air pollution brought about by urbanization,industrial development, and the increasing use of motor vehicles, has resulted in mountingdangers to the public health and welfare, including injury to agricultural crops andlivestock, damage to and the deterioration of property, and hazards to air and groundtransportation;iii. Air pollution prevention (that is, the reduction or elimination, through any measures, of theamount of pollutants produced or created at the source) and air pollution control at itssource is the primary responsibility of Government and;iv. Local financial assistance and leadership is essential for the development of localprograms to prevent and control air pollution. PurposesThe purposes of this policy are:i. to protect and enhance the quality of the Nation’s air resources so as to promote the publichealth and welfare and the productive capacity of its population;ii. to initiate and accelerate a national research and development program to achieve theprevention and control of air pollution;

107iii. to provide technical and financial assistance to the government in connection with thedevelopment and execution of the air pollution prevention and control programs;iv. to encourage and assist the development and operation of regional air pollution preventionand control programs; andv. to development of an air quality measurement and surveillance programme.9.1.5. Pollution preventionA primary goal of this policy is to encourage or otherwise promote reasonable governmentalactions, consistent with the provisions of this policy, for pollution prevention. To achieve theobjectives defined above the regulatory authority intends to implement a strategy based on thefollowing axes:9.1.5.1. Air pollutant monitoring, analysis, modeling, and inventoryIn order to achieve the standards determined, the regulatory authority shall conduct a program ofresearch, testing, and development of methods for sampling, measurement, monitoring, analysis,and modeling of air pollutants. Such program shall include the following elements:• Consideration of individual, as well as complex mixtures of air pollutants and their chemicaltransformations in the atmosphere.• Establishment of a national network to monitor, collect, and compile data withquantification of certainty in the status and trends of air emissions, deposition, air quality,surface water quality, forest condition, and visibility impairment, and to ensure thecomparability of air quality data collected in different regions.• Development of improved methods and technologies for sampling, measurement,monitoring, analysis, and modeling to increase understanding of the sources of ozoneprecursors, ozone formation, ozone transport, regional influences on urban ozone, regionalozone trends, and interactions of ozone with other pollutants. Emphasis shall be placed onthose techniques which: improve the ability to inventory emissions of volatile organiccompounds and nitrogen oxides that contribute to urban air pollution, includinganthropogenic and natural sources; improve the understanding of the mechanism throughwhich anthropogenic and biogenic volatile organic compounds react to form ozone andother oxidants; and improve the ability to identify and evaluate region-specific preventionand control options for ozone pollution.

108• Submission of periodic reports to the Ministry in charge of environment which evaluate andassess the effectiveness of air pollution control regulations and programs using monitoringand modeling data obtained.• Monitor current levels as a baseline for assessment,• Check the air quality relative to standards or limit values,• Inform the public about the air quality and raise the awareness,• Develop warning systems for the prevention of undesired air pollution episodes,• Develop and test analytical instruments and support legislation in relation to the air qualitylimit values and guidelines.Specifically, the regulatory Authority:• Shall publish proposed regulations prescribing a national primary ambient air qualitystandard and a national secondary ambient air quality standard for each air pollutant forwhich air quality criteria have been issued; and• After a reasonable time for interested persons to submit written comments thereon shouldby regulation promulgate such proposed national primary and secondary ambient airquality standards with such modifications as he deems appropriate.With respect to any air pollutant for which air quality criteria are issued, the regulatory authorityshall publish, simultaneously with the issuance of such criteria and information, proposed nationalprimary and secondary ambient air quality standards for any such pollutant.• National primary ambient air quality standards prescribed by the regulatory authority shallbe ambient air quality standards; the attainment and maintenance of which in the judgmentof the regulatory authority, based on such criteria and allowing an adequate margin ofsafety, are requisite to protect the public health.• Any national secondary ambient air quality standard prescribed shall specify a level of airquality the attainment and maintenance of which in the judgment of the regulatoryauthority, based on such criteria, is requisite to protect the public welfare from any knownor anticipated adverse effects associated with the presence of such air pollutant in theambient air.

1099.1.5.2. Pollution prevention and emissions controlIn general, the regulatory authority shall promulgate regulations establishing emission standardsfor each category or subcategory of major sources and area sources of hazardous air pollutantslisted for regulation. The regulatory may distinguish among classes, types, and sizes of sourceswithin a category or subcategory in establishing such standards.Emissions standards promulgated under national air policy and applicable to new or existingsources of hazardous air pollutants shall require the maximum degree of reduction in emissions ofthe hazardous air pollutants that the Administrator, taking into consideration the cost of achievingsuch emission reduction, and any non-air quality health and environmental impacts and energyrequirements, determines is achievable for new or existing sources in the category or subcategoryto which such emission standard applies, through application of measures, processes, methods,systems or techniques including, but not limited to, measures which:• reduce the volume of, or eliminate emissions of, such pollutants through process changes,substitution of materials or other modifications;• enclose systems or processes to eliminate emissions;• collect, capture or treat such pollutants when released from a process, stack, storage orfugitive emissions point;• are design, equipment, work practice, or operational standards (including requirements foroperator training or certification); or• are a combination of the above?The maximum degree of reduction in emissions that is deemed achievable for new sources in acategory or subcategory shall not be less stringent than the emission control that is achieved inpractice by the best controlled similar source, as determined by the regulatory authority. Withrespect to pollutants for which a health threshold has been established, the regulatory authoritymay consider such threshold level, with an ample margin of safety, when establishing emissionstandards.

1109.1.5.3. Car emissions inspection and control programThe regulatory Authority shall establish the standards, requirements and procedures applicable toall motor vehicles, old model years and newer with the exception of the five newest model years. Itshall:• Prepare a proposal to strengthen the control of emissions from petrol vehicles;• Propose emission control for road or non-road mobile sources; and• Set up a Pilot Green Transport Fund to encourage the introduction of innovative transporttechnology.In this regard, the following have also to be taken into consideration:i. No motor vehicle that is subject to the regulation may be granted registration unless is incompliance with the applicable emissions standards determined at an official inspectionstation.ii. Any motor vehicle should be deemed to be in compliance with the applicable emissionsstandards if the test results are equal to or less than the emissions standards applicable tothe motor vehicle.iii. Any motor vehicle should be deemed to be in noncompliance with applicable emissionsstandards if the test results are greater than the emissions standards applicable to themotor vehicle.iv. Any motor vehicle which fails its initial emissions test shall be deemed to be in compliancewith applicable emissions standards if not later than the registration expiration date, themotor vehicle either (1) is repaired and is in compliance with applicable emissionsstandards as determined by an emissions retest at an Official Inspection Station, or (2) isgranted a waiver.v. All owners and operators of motor vehicles subject to the provisions of this rule shallmaintain their motor vehicles and any air pollution control equipment on the motor vehiclesin good working order such that they meet the emission standards specified in this rule.vi. A certificate of compliance shall be issued to owners or operators of motor vehicles thatpass the emissions test and tampering inspection and to motor vehicles that are granted awaiver in accordance with this rule.

1119.1.5.4. Oil quality standardsAtmospheric emission introduced to the environment from fuel combustion, incineration andindustrial emission sources are causing increasing concern to air pollution. The emissions are notonly posing threat human and animals but they may also affect the meteorological and geophysicalset up such as the scattering of solar radiation back into the space and reducing visibility. Thus, theprinciple concern of the regulations is toward the control of the smoke and solid particulatesemission from the burning wastes. Smog forming compounds and other air toxics are released atevery stage of oil and gas development.Oil production and utilisation emit a variety of air pollutants including NOx, carbon monoxide andcarbon dioxide. During well completion, tons of VOCs may be vented or flared. Oil and naturalgas condensate tanks and glycol dehydrators release VOCs. Compressor stations emit a variety ofozone-forming compounds, as well as other air pollutants. Therefore, the regulatory authority shallprovide additional standards to those provided for a petrol filling station aiming at:i. Cutting emissions and oil operators must cut overall emissions of volatileorganic compounds (VOCs) from condensate storage tanks;ii.iii.Emission controls and oblige oil operators to install emission controls on condensatestorage tanks;Air quality reporting by providing an annual report on how the oil and gas industry isaffecting air quality across the state.9.1.5.5. Tax incentive to eco-carsThe regulatory Authority should provide or establish measures that can encourage the car user andcar owners to opt for ecology cars through positive and negative related taxes. In this regard, theregulatory Authority in conjunction with other related competent institutions, should:i. Introduce a subsidy to encourage the use of eco-cars;ii. Providing tax incentives to encourage use of environment-friendly vehicles andwaiving first registration tax for electric vehicles;iii. Impose road taxes based on CO2 emissions;

112iv. Impose to all insurance companies to provide a certain amount of their incomeprofits in the protection of environment, with a special focus on car emissionpollution.9.1.6. Mandate of regulatory authorityRegulatory Authority has been entrusted by the Ministry in Charge of environment for theregulation of the air quality monitoring in Rwanda. For this reason, the regulatory authority shall:i. Administrate this policy in consultation with the Ministry. This policy and the regulationsadopted pursuant to this policy should be enforced by the Regulatory Authority.ii. Have the power to make, publish and enforce all regulations that are necessary toimplement and pursuant to this policy.iii. Prepare, publish, or issue any materials that the Regulatory Authority determines to benecessary for the dissemination of information concerning the activities of the RegulatoryAuthority under this policy in consultation with the Ministry.iv. Have the power to impose administrative penalties (as per Law N° 39/2001 of 13/09/2001)for the failure to comply with this policy.v. Manage and regulate point sources of air pollution which have the potential to causematerial or serious environmental harm or an environmental nuisance in such a manner asto not prejudice the achievement of the environmental values identified in this Policy.vi. Where necessary regulatory limits on the concentration or emission rate of pollutants thatmay be emitted from a new or significantly upgraded point source of air pollution shall beestablished by the regulatory authority.vii. Provide the regulatory controls and monitoring requirements applied to a point source ofair pollution proportionate to the level of environmental risk posed by the emission ofpollution from that source.viii. Require a responsible person in relation to a significant source of air pollution which is inexistence at the time this Policy is made to progressively reduce the emission of pollutantsfrom that source.ix. Manage and regulate diffuse sources of air pollution that have the potential to causematerial or serious environmental harm or an environmental nuisance in such a manner aswill protect the environmental values identified in this Policy.

1139.1.7. Policy recommendationsBasing on the existing policy related to the environment protection and the above proposedstandards, the following observations should be taken into consideration:i. Specific standards on air pollution should be provided and revised when deemednecessary;ii. Established standards should be guided, not only by National Air Status, but also by regionand international air status as the pollution of foreigner States may have an impact on theNational Air status;iii. All public institutions dealing, directly or indirectly, with environment protection combinetheir efforts in order to promote, prevent and protect the Rwandan Ambient Air. This canbe possible if they harmonize their respective policies aiming at environment protection;iv. Researcher’s assessment on the air status in order to improve or maintain a sustainableclean ambient air;v. Establishment or review of environment standards.Other strategies to be undertaken by car users within Kigali City in order to Reduce Air Pollutionfrom Transport: drive less; walk or ride your bike to nearby places; ride the bus on your commute towork or school; use the internet to shop or find out information instead of driving where it ispossible; maintain your vehicle properly; refuel after 5:00p.m. To reduce ground-level ozone; stopat the click when fueling up to reduce gasoline vapors and spills; and keep your tires properlyinflated.9.1.8. Stockholder’s collaborationSince the environmental degradation is such a pervasive problem, a wide-reaching andcomprehensive enforcement apparatus is required to cope with it. Different institutions havingimpact, being direct or indirect, on the environment protection have due regard to the preservationand protection of the environment, the conservation of natural resources and the health and safetyof environment beneficiaries. It is in this regard; RRA, REMA, RBS, RNP, researchers, etc. shouldcollaborate in order to avoid interference of their respective missions.

1149.1.8.1. Rwanda Revenue Authority (RAA)RRA shall have the following main responsibilities, in accordance with taxation incentives for“Green Cars”:• participating in fixing, collecting, controlling and managing tax incentives measures foreco-cars in accordance with the law and modalities pertaining thereto established by theregulatory authority;• granting tax waivers or incentives measures as provided for by relevant policy legalprovisions according to the procedures it prescribes;• exercising judicial police powers to investigate any air pollutant, especially entering cars;• carrying out any other activity related to the protection of environment upon request by theregulatory authority as far as potential cross-border pollutants are concerned;9.1.8.2. Rwanda Environment Management Authority (REMA)Rwanda Environment Management Authority will be entrusted by the Ministry with the followingresponsibilities related to environment protection:• Prepare and publish technical guidelines for the inspection of car emissions.• In collaboration with the police, the Regulatory Authority and other competent authoritiesshall identify suitable sites for car emission inspections and provide the necessaryequipments for that purpose.• Coordinate the environmental impact assessment process of car emissions.• Coordinate inspection, monitoring and follow up activities to ensure compliance withapplicable air environmental standards and regulations in place.• Preparing rules and regulations aiming at the improvement of the ambient air which shallbe approved by the Minister in charge of environment.• Providing the strategic vision and action plan aiming at the improvement of ambient air andenvironment protection;9.1.8.3. Rwanda Bureau of Standards (RBS)The main responsibilities of the Bureau of Standards as the body with powers to define nationalstandards are as follow:• defining national air environment standards, coordinating all the activities in relation tostandards, ensuring their application and observance in the country;

115• Granting car environment standards certificates in collaboration with the police;• In collaboration with RRA, ensure that all new cars entering the country (imported) meetthe established air environment standards;• promoting and co-coordinating all the activities in relation to the definition of airenvironment standards;• assisting the Government of Rwanda in defining, devising and implementing air protectionstandardization policy;• advising on all issues pertaining to standardization in the country and collaborating withRegulatory authority or any other national or international organizations in matters relatingto air environment standardization;• setting up a standards inspection system for imported and exported products and ensuringtheir respect of environment control at all points of marketing and consumption within thecountry;• In collaboration with REMA, providing facilities or making arrangements for theexamination or inspection and testing of car emission.9.1.8.4. Rwanda National Police (RNP)In implementation of the Organic Law No 04/2005 of 08/04/2005 determining the modalities ofprotection, conservation and promotion of environment in Rwanda, the Rwandan National Policeshall have responsibility to:• Monitor whether all cars have “Air environment certificate”, in addition to the ordinarydocuments ( like car insurance deed), showing the last date of inspection and that of thenext inspection;• Impose sanctions to any car owner of the car who didn’t bring his/her car for inspectiontest;• Determine which reparations to be done in the case a car fail to pass the inspection testbefore being in circulation;• Facilitate the inspection process by conducting the air pollution inspection to all cars inaddition to the actual technical tests.9.1.8.5. Research institutesThe researchers in collaboration with the Environmental Authority shall:

116• Conduct research on environmental effects caused by car emissions, and recommendmeasures to be taken to mitigate or offset the negative effects;• Provides training, consultancy, applied research services and extends advocacy in thearea of environment protection to industries, regulatory bodies, Government Organizationsand NGOs and works towards bringing about change for a more balanced development;• Promote Information, Education and Communication activities in schools, colleges,industry etc. to enhance the knowledge base on risk of car emissions on human health.10. Concluded remarks10.1. ConclusionsThe overall objective was to develop a solid understanding of air quality in Rwanda with focus onKigali and to develop a related strategy and policy recommendations to address the pollutionissues. Methods used include literature review about urbanization, air pollution and human healthrisk. The existing standards, regulations and policies about air pollution control and air qualitymonitoring; the state of air pollution in Kigali City and the plausible consequences on human healtheffects with a focus on respiratory illnesses have been highlighted from literature review based onexiting policy framework for Rwanda including Multilateral Agreements and InternationalConventions such as Kyoto Protocol Convention; United Nations Framework Convention onClimate Change; Vienna Convention on the Protection of the Ozone Layer. Other policydocuments analysed comprise the air quality emissions standards for Rwanda and for East AfricanCommunity; the Rwanda Bureau of Standards publication and other government publications onair quality and environment policies, laws, programs and strategies.A desk <strong>study</strong> was also carried out to acquire and analyse relevant information pertaining to airpollution/air quality from previous studies in Kigali City. These include for example, themeteorological records above Kigali City (temperature, relative humidity, rainfalls, wind speed anddirection) from the Ministry of Infrastructure, the topography or Digital Elevation Model (DEM),ROAD network; land use and main sources of air pollution such industrial zones, roads trafficlights, roundabouts and car stations and stops within the <strong>study</strong> area. Medical records on upperrespiratory infections diseases such as cough, phlegm, influenza, headaches and eye irritation;and chronic respiratory disease like asthma, pneumonia, bronchitis have been acquired from the

117selected health facilities in Kigali City. A field work in selected sites to fill in gaps in existingmeasurements was also organized and the selection of the sample points was guided by thegeography of Kigali City, traffic activities and location of industries. The information on indoor airpollution was gathered from other studies which tried to measure the PM2.5 and CO using theTraditional Cooking Stoves and the Improved Cooking Stoves in rural areas.The research finding revealed that air pollution in Kigali City is an already an increasing problemwhich may have many effects and facts to the life of population. The rapid urban population ofKigali City in the last decade has resulted in unplanned urban development, rising rate ofmotorization and increase in consumption; and then air pollution problems. The situation isexacerbated by increasing number of vehicles, inadequate inspection and maintenance of facilities;Adulteration of fuel products; improper traffic management system and road conditions, high levelsof pollution at traffic intersections; absence of effective mass rapid transport system. The mainsources are vehicles; industries and power plant units; domestic fuel and household woodscombustions. Meteorological and topographic conditions of the Kigali City have been pointed outas the dispersion factors of air pollutants into the atmosphere especially in dry seasons.Today, the mountains around Kigali City are hardly rarely visible due to very severe deterioration ofambient air by pollutants, specially, suspended particulates and ozone which are caused byincreased number of gas guzzling and smoking old vehicles driven on severely dusty roads andsidewalks, population increase, low quality fuel, used motor oil, wood, and coal, and intensesunlight promoting photochemical reactions. The number of motorized vehicles is now reachingalmost 300 thousands in the city. High elevation and intense sunlight trigger ozone formation. Inaddition, due to inversion, air pollution is generally worse in the dry season, when thermalinversions are more common.A number of influencing factors of the quantity of emissions from transport sector have beenidentified as the frequency that vehicles are used; extent to which the vehicle is used (excessive);the age of the vehicle fleet; the technology used within it; and the extent to which vehicles areproperly maintained; the availability of appropriate fuels and the extent to which they are usedproperly. Concerning the current state of air pollution in Kigali City, the measurement results on

118suspended particulate matter showed that Kigali City exceeded already the recommendations ofthe WHO (50 μg m 3 ). Inhabitants of Kigali are therefore exposed to enormous levels of PM10 duringmost of their time outdoors especial in the evening hours. A seasonal variation was found asconsistently higher dust load was found in the dry seasons which might possibly be attributed tothe prevailed meteorological conditions such as low precipitation and wind speed. Likewise, theconcentration of ground-level ozone is already beyond the major environmental standards, and theproblem of air pollution is already at present. When considering the scale of industrial activities inKigali, we can assume that the primary source of this pollution is motor vehicle exhaust especiallycaused by bad maintenance of its emission control. Even if the sulphur dioxide released in theatmosphere of Kigali City was found low when compared to the accepted annually averagerecommended by East African Standard for some common substances found in polluted air (80g/m 3 for industrial areas, 60 g/m 3 for residential areas; a 15 g/m 3 controlled areas), the sulphurdioxide is already a concern for inhabitants especially during the dry seasons, as the measurestaken at KIST air quality monitoring were beyond the permissible limits.Like many other cities of the world, Kigali City has not yet made major efforts to reduce airpollution. The regulatory regime on air pollution control and reduction still has to be improved inRwanda. The environment management acts exist in Rwanda but relevant regulations and theirenforcement are yet to be formulated and finalized. Limited institutional capacity and technicalinfrastructure such as finding, equipment and human resource have been identified in this <strong>study</strong>.Very limited information and is another challenge as there is no systematic quantitativeassessment of the magnitude of the air quality due to inadequate capacity and resources. The levelof public awareness on the air pollution problems and associated adverse effect to human healthand environment is still low. The rapid growth of rural and urban population coupled with poorurban planning which allows for inappropriate allocation of economic activities within Kigali City isalso leading to air pollution. Inadequate institutional coordination and collaboration betweengovernment institutions can lead to the lack of common strategies. Inadequate involvement ofmajor stakeholders (e.g. local community, NGOs, private sector, industries) in addressing theenvironmental problems has been noticed.

119As Kigali City urbanizes and the traffic density continues to grow, the resulting increase in airpollution is becoming an alarming concern for its inhabitants especially during the dry seasons. Thesustainable urban management of Kigali City calls therefore for taking comprehensive measures toreduce the air pollution problem and its related human health effects.10.2. RecommendationsRecognizing that transportation is a major pollution source in Kigali City, any strategy that gearedto reduce or control atmospheric pollution has to include a transportation improvement program.The main programs to combat air pollution in Kigali that need to be considered but not limited toinclude:i. Establishment of continuous air pollution monitoring system/schemes in KigaliCityThere is a need to establish the air pollution taskforce in Rwanda and to build the existing capacityto include training of scientists in learning institutions focusing on modelling and impactassessment of air pollution in Rwanda. The flowing map shows where the air quality/pollutionmonitoring stations and its infrastrurure may be located in Kigali City.Figure 30: Proposed sites for air pollution monitoring stations

120The suitable site for air pollution monitoring stations have been proposed in the southern parts ofKigali City where the concentration of air pollution would expect to be highest than other areasbecause the general annual trend of wind direction is from North and North-East to the South.ii. Improving the transport system in urban areasMotorized transport is one of the major sources of air pollution particularly in Kigali City due totraffic congestion since vehicles release more pollutants when idling than when speeding; andinefficient motor vehicles especially second-hand vehicles which not only pose mechanicalproblems but also environmental problems. In this regards, there is a need to promote publictransportation with bigger capacity of passengers and newer quality (such as ONATRACOMbuses) and whiles also discouraging the small cars use in transport like the mini-bus of ATRACO.Other control strategies are also required for instance the control of the number of private cars;prohibit the import of old cars, impose high tax on gas guzzlers, encourage car pooling andtelecommuting; strictly control quality of imported fuels, promote the use of low sulfur diesel,introduce the use of catalytic convertors to reduce exhaust emissions; control engine conditions.

121Since incomplete combustion in old or poorly maintained engines is a direct cause of carbonmonoxide and unburned hydrocarbon emissions, the enforcement of engine maintenancestandards should be another goal of traffic. The major compulsory program implemented in thisdirection in other countries for example the United Sates is called the Inspection and MaintenanceProgram. It is a costly program, however, in Kigali City this process can be simplified by authorizingtraffic inspectors to stop smoking vehicles until they have been repaired and do not smoke anylonger. Reduction of lead and sulfur in fuels and finally the introduction of catalytic converters willdrastically reduce pollution. To significantly reduce emissions of dust by traffic and winds, a goodstrategy would be to populate the dusty roads, vacant areas, and parking lots by those trees andshrubs that are native to the area. The intensification of pavement of dirt roads and othersecondary streets can also be promoted if the financial means are not a constraint.iii. Promoting the public awareness and education.Awareness creation efforts should continue targeting key stakeholders (policy and decisionmakers, journalists, industrialists) as well as mainstreaming air quality management in schoolcurricula. It may be worth supporting NGOs and professional associations dealing with awarenesscreation action. Another option would be to collaborate with the mass media to launch extensiveenvironmental campaign on pollution prevention topics for free.iv. Promoting the use of renewable energy sources such bio-fuelIn an effort to find a solution to the current problem of fuel and air pollution from vehicularemissions in Rwanda; there is a need to support biodiesel research and development as a majorcomponent of renewable energies. With this regards, the IRST is exploring the use of biodiesel asa renewable energy. There are huge benefits that can result from the development of a biodieselindustry in Rwanda including the improved environment and health; easy blending with petroleumdiesel; better engine lubrication; and safe transportation. Indeed, Biodiesel fuel burns up to 75%cleaner than conventional diesel fuel made from fossil fuels. Biodiesel substantially reducesunburned hydrocarbons, carbon monoxide and particulate matter in exhaust fumes. Sulphurdioxideemissions are eliminated as biodiesel contains no sulphur. Biodiesel is plant-based and adds noCO 2 to the atmosphere. The ozone-forming potential of biodiesel emissions is nearly 50% less thanconventional diesel fuel. Biodiesel exhaust is not offensive and doesn't cause eye irritation.

122Biodiesel is environmentally friendly: it is renewable, "more biodegradable than sugar and lesstoxic than table salt“. Biodiesel can be used in any diesel engine. Fuel economy is the same asconventional diesel fuel. Biodiesel is a much better lubricant than conventional diesel fuel andextends engine life. Biodiesel has a high cetanerating, which improves engine performance: 20%biodiesel added to conventional diesel fuel improves the cetanerating 3 points, making it apremium fuel (Nduwayezu, 2010).v. Conduct an impact assessment on health and environment10.3. Actions related to recommendationsRecommendation Actions (not exhaustive) ResponsibleAir pollution monitoringsystem/schemes in Kigali CityBiodiesel research anddevelopmentSelection of the responsible entitiesEstablishment of monitoring strategySelection of suitable for locating themonitoring stationsMonitoring station establishment outof KigaliReahabilitation of weather stations inRwanda, especially in urban areasEstablishment of the Nationalambient air quality standardsSet up of a large plantation onmarginal lands and degraded hilltopsfor jatropha, palm, soy, moringasugar...etc.Creation of Biomass ResearchCentreEstablishment of more biofuellaboratories in different areas ofRwandaPilot Green Transport Fund toencourage the introduction ofinnovative transport technologyIncentive for the car user and carREMAREMAREMA, MININFRAMININFRAMININFRARBSISAR, MINAGRI, IRST,NURIRSTIRSTREMA, IRSTREMA,RRA

123Improving public transport inurban areasProhibiting importing old carsor restriction of car’simportation that is older thanspecific years of productionPromoting the publicawareness and educationowners to opt for ecology carsRoad network improvement to caterto the over-increasing car populationon roadsTo put in place an efficient andconvenient public transport systemwithin Kigali CityIncrease the carrying capacity ofpublic buses by phasing out mini-bustaxis and introducing buses withhigher capacity such as the longbuses or articulated busesTo create a conducive for greentransport (walking and cycling )where is possibleCar emissions inspection and controlprogramAny motor vehicle should be incompliance with the applicableemissions standards determined atan official inspection stationSpecifications of fuels to be used inRwandaIntroduce a subsidy to encourage theuse of eco-cars.Institute a dynamic program inschools of the country at all levelsEducate the future generation of thecountry on the health effects of airpollution and pollutionpreventionMININFRAMININFRA and KigaliCityRURA, RRA, ATRACO,ONATRACOMKigali CityRNP, RBSRNP, RBS, RRAMINICOMMINICOM, RRAMINEDUC and all Highlearning InstitutionsMINEDUC; High learningInstitutions, Mass Media(Rwanda Radio RwandaTelevision....).

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