Seasonal size distribution and possible health implications of atmospheric aerosols collected from a rural site of eastern central India

Özet

This paper contributes for the first time the seasonal mass size distribution of atmospheric aerosols andtheir possible health implications in a rural area of eastern central India. Size-segregated atmosphericaerosols were collected from July 2012 to June 2013 at rural site near Mahanadi riverside basin of Rajim (20590N and 81550E), Chhattisgarh, India using nine-stage cascade impactor. Bimodal size distribution wasfound with stable peaks at 0.4e0.7 mm (fine mode) and 4.4e5.8 mm (coarse mode) during monsoon, winter,spring and summer seasons at study site. The mass median aerodynamic diameter of total impactor particlesizes was shifted from lower particle size inwinter to higher particle size in summer. High concentrations ofsize-segregated aerosols were found during winter season with 45%, 55% and 36% of PM2.5e10, PM2.5 andPM1, respectively of the total PM10 aerosol. One unique observation was that the mass concentration ofparticulate matter increases abruptly in May and June during summer season, which was due to in situburning of rice crop residues. The concentrations of upper respiratory tract and lungs particles were foundto be highest during winter whereas respiratory airways particles showed maxima during summer season.The highest numbers of unfavorable days (i.e. value of air quality index > 101) were also observed duringwinter followed by summer season. The significant positive correlations found among particle in fine sizebins (<0.43e2.5 mm) during winter and summer season was mainly due to the biomass burning activitiesduring the study period at a rural site in eastern central India.