Chemical characterization of particulate matter at Sinhagad, a high altitude station in Pune, India

PM10 and PM2.5 samples were collected at Sinhagad, a rural high altitude location, nearby Pune, India, during Nov. 2008 to April 2009. The average concentrations of PM10, PM2.5 and PM10-2.5 at Sinhagad were 35.8, 14.1 and 21.7 µg m-3, respectively. The average ratio of PM2.5/PM10 (0.39) suggested that PM10 at study area is dominated by primary particulate emissions by natural activities. In PM10, anions and cations were contributed 33% and 67% whereas in PM2.5 these were 43% and 57%. In both PM10 and PM2.5, contribution of marine components viz. Na+, Cl- and Mg2+ were found to be 58% and 49%, respectively, reflecting Arabian sea is the major source of these components. All the ionic components in PM10 showed higher concentration in summer whereas in PM2.5, secondary particles (SO42-, NO3- and NH4+) showed higher concentration in winter. The order of neutralization factor was found to be Ca2+ > Mg2+ > NH4+ > K+ for PM10 and Ca2+ > NH4+ >Mg2+ > K+ for PM2.5. During the sampling period, major contribution from marine sources was observed (43% for PM2.5 and 53% for PM10) followed by crustal sources (PM2.5: 25% and PM10: 30%) and anthropogenic sources (PM2.5: 32% and PM10:17%)