Assesment of PM 2.5 and PM 10 in the air sample of Chapra town (Bihar)

A sampling campaign was carried out in Chapra town of Bihar for assessing mass concentration of PM 2.5 and PM 2.5-10 so as to correlate it with the air quality of the town. Concentration of a dozen of elements namely Cr, Cu, Cd, Ni, Mn, Zn, Pb, Na, K, Ca and Al were quantified. Sampling was done on nuclear polycarbonate filters. For principal component analysis (PCA) of elements and mass concentration data, three main sources were identified as particulate matter producers. They are resuspended crustal dust, industrial emissions and vehicular exhaust. The effects of weather conditions were also studied. It was found that pollution in summer was higher than those in winter. The PM2.5/PM2.5-10 ratio in summer was found in the range of 0.35-0.9 whereas the same ratio in winter was in the range 0.20-0.50. The concentration of both types of particles exceeded the permissible WHO limits.