African Water Development Report 2006 - United Nations Economic ...

Fertilisers are also a potential threat and althoughpollution from the use of agricultural fertilisersis still negligible. It can be seen from figure 6.5that there is a general tendency towards increasingthe introduction of fertilis ers into agriculturalproduction in various countries, especiallythe Northern African countries of Egypt andMorocco, the Southern African countries ofSouth Africa and Zimbabwe and, to a lesser extent,Ethiopia, Nigeria and Kenya. Dental andskeletal fluorosis, a condition related to saltwaterproblem, occurs in several areas, particularlyAfrica’s east coast. All hope is not lost as someefforts are under way in Africa to fight pollutionand monitor raw water sources; selected examplesare given in boxes 6.1-6.3.Protecting Ecosystems in AfricaBox 6.1Tracing Pollutant Sources in CameroonFeudjio (2002) and Tchinda (2002) carried out analyses on the wastewater management in the Dschang DistrictHospital and the University Teaching Hospital (UTH), Yaounde, respectively. At the District Hospital in Dschangit was found that a significant part of wastewater from laundry, and cleaning of wards is directed to drains and flowinto the environment. In Yaounde, it was noted that the treatment station for the hospital was broken down andabandoned for years. About 67 m 3 of wastewater is produced daily in the heart of the capital from this hospitaland discharged into the environment mainly without treatment. Physico-chemical and microbiological analysesof the water discharged into the environmental are shown in the table below. Compared to the recommendedlimit of pollutants, the effluents are hundreds to thousands of times beyond the level allowed.Physico-chemical AnalysesPollutantsDschang DistrictHospitalUniversity TeachingHospitalMINIMUM RecommendedLimitChemical Oxygen 1960 643.3 120.0Demand, (COD) mg/lBiological Oxygen 950 258.3 30.0Demand (BOD 5), mg/lSuspended Solids, mg/l 2760 136.4 30.0Phosphates, mg/l 122.5 17.6 50.0Nitrates, mg/l 10.0 1.5 0.5Microbiological AnalysesWHO Standard, No. of microorganismsMesophilic aerobic > 10 5 > 10 7 < 20 per mlGermsTotal Coliform > 10 4 > 10 6 < 10 per 100 mlFaecal coliform > 10 2 > 10 5Faecal Streptococci > 10 3 > 10 5 < 1 per 100 mlAnaerobic> 10 5 < 1 per 20mlSulphur reducersE coli > 3* 10 4per 100 ml0.0 per 100 mlSource: AWDR National Report135