Annual Report, Eighth Edition - Montana Legislature

EQC Eighth Annual Report - Page 4and people with health problems are especially sensitiveto sulfur pollution.Most observations of the health effects of sulfurcompounds come from episodes of high SO2 at thesame time total suspended particulate levels are high.Normally, the upper respiratory tract absorbs SO2,but particulate matter can carry sulfur compounds tothe innermost recesses of the lungs, thereby causinggreater damage than either would cause alone. Thepollutants act synergistically; their effect together isgreater than the sum of their individual effects.High concentrations of SO2 can cause chlorosis inplants, which is a discoloring of leaf tissue due to aloss of chlorophyll. During acute exposure, leaf tissuemay die. Sternberg (1981) documented significantdecreases in crop yield from SO2 pollution. Becausemany forage plants are sensitive to SO2, livestockgrazing can be adversely affected. The SO: also reactssynergistically with ozone and NO:, damaging plantsat lower concentrations than any of the pollutantswould by itself.Acid mists, or high concentrations of suspendedacidic droplets, can corrode metals and cause extensivedamage to steel rails,buildings and structures.Carbonate building materials, such as marble, concreteand mortar, are particularly susceptible todamage from acid mist. H2S can also tarnish and corrodemetals, particularly silver and copper.pulmonary edema, can result from high NO2 concentrations.Studies have yet to demonstrate direct humanhealth problems caused by hydrocarbons. However,hydrocarbons contribute to photochemical oxidants,which do affect people. The oxidants irritate the eyes,nose and throat, and often the respiratory tract. Manyresearchers believe that high oxidant levels alsodebilitate athletic performance and harm asthmatics.Photochemical oxidants significantly reduce visibility.This can reduce tourism and population growthin certain areas. Ozone damages many materials. Forexample, it attacks organic and synthetic fibers anddeteriorates rubber. Photochemical oxidants are thecountry's most significant plant-damaging pollutant.Carbon MonoxideThe incomplete combustion of organic fuel producescarbon monoxide (CO), a colorless and odorlessgas. The principal sources of CO are motor vehicles,but other sources in Montana include oil refineries,the wood products industry, and wood stoves andfireplaces.Photochemical OxidantsIt takes a complex series of chemical reactionsamong nitrogen oxides, hydrocarbons, and sunlight toproduce photochemical oxidants. These are compoundscapable of oxidizing substances that commonoxygen in the air cannot. The nitrogen oxides usuallyoriginate from the high-temperature combustion offossil fuels, particularly in automobile engines.Hydrocarbons, containing only carbon and hydrogen,also mainly originate in motor vehicles. Smallersources include petroleum refining and transfer operationsand evaporation of industrial solvents used inpainting and dry cleaning.EffectsCarbon monoxide outcompetes oxygen for theblood's hemoglobin. High levels of CO significantlydecrease the flow of oxygen to the areas of the bodythat depend on it most: the heart and the brain. Asthe oxygen concentration carried by the hemoglobindecreases, the heart must work harder to compensate,in turn increasing its need for oxygen. Symptoms ofexcess CO exposure include headaches, dizziness,fatigue, and sluggish reactions; excessive exposure canlead to death. CO may inhibit the bioelectric functionsof the brain, and thus impair intellectual ability.Heart patients, smokers, young and old people, pregnantwomen and persons on medication may be particularlysusceptible to high concentrations of CO.EffectsNitrogen dioxide in high concentrations creates anunpleasant odor and diminishes night vision. A studyof school children living near an explosives plant thatproduced NO2 showed an increase in respiratoryillness and decreased ventilatory function. Lungdamage, including bronchial damage and acuteFluorideFluoride sources include aluminum, glass, brick,phosphate fertilizer and elemental phosphorus plants;