Aditi Kulshrestha

Metal concentration of PM2.5 and PM10 particles and seasonal variations in urban and rural environment of Agra, India

Three monthly 24-hour samples of airborne aerosols (PM(10) and PM(2.5)) were collected at an urban and a rural site of the North central, semi-arid part of India during May 2006 to March 2008. Seven trace metals (Pb, Zn, Ni, Fe, Mn, Cr and Cu) were determined for both sizes. The annual mean concentration for PM(10) was 154.2 microg/m(3) and 148.4 microg/m(3) at urban and rural sites whereas PM(2.5) mean concentration was 104.9 microg/m(3) and 91.1 microg/m(3) at urban and rural sites, respectively. Concentrations of PM(10) and PM(2.5) have been compared with prescribed WHO standards and NAAQS given by CPCB India and were found to be higher. Weekday/weekend variations of PM(10) and PM(2.5) have been studied at both monitoring sites. Lower particulate pollutant levels were found during weekends, which suggested that anthropogenic activities are major contributor of higher ambient particulate concentration during weekdays. Significant seasonal variations of particulate pollutants were obtained using the daily average concentration of PM(10) and PM(2.5) during the study period. PM(2.5)/PM(10) ratios at urban and rural sites were also determined during the study period, which also showed variation between the seasons. Three factors have been identified using Principal Component Analysis at the sampling sites comprising resuspension of road dust due to vehicular activities, solid waste incineration, and industrial emission at urban site whereas resuspension of soil dust due to vehicular emission, construction activities and wind blown dust carrying industrial emission, were common sources at rural site.

Characteristics of polycyclic aromatic hydrocarbons in indoor and outdoor atmosphere in the North central part of India

Twenty-three polycyclic aromatic hydrocarbons (PAHs) were measured simultaneously in indoor and outdoor environment of ten homes at urban and roadside sites in the north central part of India during winter season (November 2006 to February 2007). The average concentration of total PAH (TPAH) was 1946.84 ng/m(3) in kitchen, 1666.78 ng/m(3) in living room and 1212.57 ng/m(3) in outdoors at urban site, whereas at roadside site it was 2824.87 ng/m(3), 2161.26 ng/m(3)(,) and 3294.28 ng/m(3) in kitchen, living room and outdoors respectively. The two, three and four ring PAHs were predominant in vapour phase, while the five, six ring PAHs were primarily associated with the particulate phase. The concentration trends of the PAHs in present study were naphthalene>2-methylnaphthalene>1-methylnaphthalene>biphenyl>acenaphthylene in indoor and outdoor environment of both the sites. The spatial trend of total PAHs concentrations in the house located at urban sites, was kitchen>living room>outdoors whereas at roadside site, the trend was outdoors>kitchen>living room. Correlation analysis has been used to identify the sources of PAHs. The correlation between CO(2) and ratio of living room/outdoors (L/O) and kitchen/outdoor (K/O) of total PAHs concentration for two sites was found to be significant.