Study of continuous profile of specific urban pollutants

Abstract

In this study, the air pollution level of the area located near the Pan Pacific Hotel Sonargaon has been assessed continuously using the Environmental Monitoring Unit for a period of 28 days (from July 19 to August 01 and August 26 to September 08, 2001). The parameters studied were: Carbon Monoxide (CO), Sulfur Dioxide (S02), Nitrogen Oxides (NO,), Carbon Dioxide (C02), Total Hydrocarbons (THC) and Ozone (OJ). Generally, the concentration levels of the parameters studied remain low from 12 pm (midnight) to 8:00 am, then these start to rise and attain high level during 7 pm - 11 pm~'This fact indicates that the concentration levels largely depend on the number and the nature of the vehicles on the road. The results show that the concentration levels of all pollutants studied exceed the standard levels recommended by the Department of Environment (DOE) Bangladesh and Environmental Protection Agency (EPA) USA. It has been observed that the vehicular emissions are the main sources of air poll~tion of the area. Compared to weekends the air pollution levels on the weekdays were observed to be higher as the number of vehicles increased during weekdays. The rain and wind condition have significant influence on the concentration of the parameters studied. It has be,en noticed that the rain decreases the concentration of C02. NO, and S02 in the air. The concentration levels of the parameters studied observed during the period from 7 p.m. to II p.m. exceed the standard values recommended by DOE, Bangladesh. The measured concentrations of Particulate Matter ::;10 mIcron (PM 10) are, very high compared to the EPA standard value. The average concentration was found 422.7 microgram/mJ but the EPA limit is 150 microgram/mJ.