Abstract

Air pollution in urban area is a major environmental issue of the developing countries all over the world. Khulna is one of the most polluted cities in Bangladesh. The air environment of Khulna has been deteriorating rapidly during the last couple of years especially due to migration of highly polluting 2-stroke engine banned vehicles from Dhaka. The residents of Khulna frequently complain about headache, eye and throat irritation and breathing problem. The situation is expected to be worsening further with the increase of population, economic development and high influx of people from rural areas.

In this study, a detail analysis of the vehicle population structure and trends in Khulna city from 1990 to 2002 has been performed. The study also investigates the role of different types of motor vehicles in the ambient air in Khulna City. The total number of vehicles were 54,536, among them Car and Taxi, Jeep, S wagon, M Bus, D Bus, D Truck, 3- W vehicle, 2- W vehicle were 18, 11, 11, 16, 14 and 30 percent respectively. The average increasing rate of vehicles was about 8 percent. It is observed that the increase of 3-wheeler vehicles, Diesel bus, and Diesel track has major contributions to NOx emission in Khulna city. The 2-wheeler vehicles have not significant role in NOx and SOx emission although its population occupies the highest position among all other vehicle categories. In 2002, the total NOx emission was 11,257 tons among this Diesel track, 3-wheeler vehicle and Diesel bus contribute 47,28 and 15 percent respectively. The total SOx emission from vehicle was 8,237 tons in 2002 and the main contributor Diesel track occupied 68 percent.

This study also investigates the effect of vehicular air pollution on human health. Major effects are noticed on vehicle staffs, shopkeepers and traffics. But there were insignificant effects on students because of their low exposure time.