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II. ENVIRONMENTAL IMPLICATIONS OF UNSUSTAINABLE DEVELOPMENT
[ II | II-A | II-B
| II-C | II-D
| II-E | II-F
| II-G | II-H |
II-I | II-J ]
B. Major brown or ambient environmental problems
[ B-1 | B-2 | B-3
| B-4 | B-5 | B-6
| B-7 ]
2. Air pollution
It is now recognized that town and cities are major contributors to the world's brown environmental problems (Department of the Environment, 1990). Good air quality is essential for human health and for the environment as a whole. There is a corresponding relationship between the increase in air pollution and the rise in respiratory diseases. Polluted air can seriously affect the quality of life among those suffering from asthma, bronchitis and similar breathing problems. Air pollution also boosts the frequency with which people, especially children, contract short-term respiratory ailments. Mortality rates resulting from cardiovascular disease, particularly among the elderly (over 65) can increase with air pollution. Air pollution also damages historic buildings and kills sensitive plant life. In the long-term it can adversely affect soil and water. The deterioration in urban air quality is mainly the result of increases in industrial and manufacturing activities, numbers of motor vehicles and per capita energy consumption.
Limited data are available on the ambient environment in NWFP. However, rapid urbanization and an exponential increase in the number of all types of vehicles has given rise to the deterioration of air quality, especially in the big urban centres of Peshawar, Nowshera, Charsadda, Mardan, Abbottabad, Mingora, Kohat, Bannu and D. I. Khan. Old vehicles which are not properly maintained are particularly a problem. Lead emissions from automobile exhausts are reportedly high in some parts of the cities during specific traffic peak hours. Indiscriminate burning of municipal solid wastes also contributes to air pollution. Dense smoke emissions from foundries, brick kilns and rolling mills in Peshawar and Nowshera have been reported.
Approximately 350 brick kilns are situated in and around Peshawar. On average, a brick kiln producing 800,000 bricks uses large amounts of rubber to start fires and burns a total of eight tons of low-quality coal or 20 drums of used vehicle oil. It is thus staggering to realize the huge amount of hazardous material that is burned by all 350 brick kilns. Hydrocarbon fuel emissions, and especially carbon monoxide, are major air pollutants. Peshawar, like other major cities of Pakistan, is facing a serious air pollution problem from rapidly increasing traffic density. According to the Police Department in Peshawar, in that city alone 143,594 vehicles were registered in 1994 compared with 83,625 in 1989, averaging an annual increase of 10 per cent. If that trend continues the number of vehicles in the city will have doubled by the year 2000.
Carbon monoxide levels from 6 a.m. to 6 p.m. were studied at 16 different locations with maximum traffic density. Twelve of the 16 locations were found to have an average carbon monoxide concentration above the threshold limit of 9 ppm for eight hours of exposure. At one location the average carbon monoxide concentration reached 35 ppm for one hour's average exposure. Those results suggest that at 12 locations, the carboxyhaemoglobin level present in the blood of people exposed to such concentrations of carbon monoxide for eight hours would be in the range 2.04-4.4.85 per cent, a level that can adversely affect the central nervous system and cause changes in psychomotor functions (Khan, A. R., and others, 1996). Another air pollution survey carried out by EPA at eight locations within the city of Peshawar showed levels of carbon monoxide as high as 14 ppm. Similarly, the levels of nitrogen dioxide and ammonia were also above acceptable levels.
Urban areas are both enormous consumers of natural resources, and producers of waste and pollution. It is now recognized that urban conditions are a major determinant of travel patterns and, hence, energy consumption. The implications are that by guiding urban development efficiently and into more appropriate forms in future, planners can contribute to reductions in energy consumption and emissions. ECOTEC (1993) pointed out that over longer periods more efficient urban conditions can have a major influence over transport usage and, hence, energy efficiency, while also reducing air pollution problems.
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