Characterization, seasonal variation, source apportionment and health risk assessment of black carbon over an urban region of East India

Abstract

Black carbon (BC) is produced due to the incomplete combustion of fossil fuels and rapidly accelerates the globe. The study of the source apportionment exploration of BC is inaccurate due to lacking observational limitations and uncertainties in emission inventories. In the present work, we measured BC mass concentrations using a 7-wavelength Aethalometer (AE-33). In this study, BC mass concentration was ranging from 2 to 13.43 μgm−3 and was minimum during monsoon (3.23 ± 0.38 μgm-3) and maximum in the winter season (11.68 ± 2.55μgm−3). The annual mean BC mass concentration and PM2.5 were reported as 6.60 ± 3.50 μgm−3 and 119.07 ± 43.44 μgm-3, respectively. In overall study, the BC aerosol was contributing 6.92% (winter), 5.09% (summer), 3.79% (monsoon) and 5.25% (post-monsoon) to the total mass concentration of PM2.5. Backward Trajectories have shown that the airborne particulate matter comes from different directions in different seasons. Correlation analysis has found a strong relationship between BC and PM2.5 (r = 0.89, r2 = 0.80). However, an inverse relationship was noticed between BC and temperature(r = −0.92), wind speed (r = −0.61), precipitation (r = −0.60) and humidity (r = −0.52) during the observational period. Apart from describing BC's atmospheric impacts, the health risk assessment of BC during various seasons over Jamshedpur city is also illustrated in detail.