Chemical composition and source apportionment of PM2.5 and PM2.5–10 in Trombay (Mumbai, India), a coastal industrial area
Sandeep Policea,b, Sanjay Kumar Sahua,b, Mahesh Tiwaria,b, Gauri Girish Pandita,b,*
PM2.5 and PM2.5–10 concentrations, elemental constituents, and sources in a densely populated coastal industrial area (Trombay, Mumbai) were investigated in 2010 and 2011. The PM2.5 and PM2.5–10 concentrations were 13.50–71.60 and 22.40–127.78 μg/m3, respectively. The daily PM2.5 concentrations exceeded the Indian Central Pollution Control Board limit (60 μg/m3) several days in winter. Of the elements analyzed, Si then Al had the highest concentrations in PM2.5–10, but black carbon then Si had the highest concentrations in PM2.5. The element concentrations varied widely by season. Al, Ca, Fe, Si, and Ti concentrations were highest in summer, Cl, Mg, and Na concentrations were highest in the monsoon season, and the other trace metal concentrations in both PM2.5 and PM2.5–10 were highest in winter. The PM2.5 and PM2.5–10 sources were apportioned by positive matrix factorization. PM2.5 and PM2.5–10 had six dominant sources, crustal material (8.7% and 25.3%, respectively), sea salt spray (6.1% and 15.0%, respectively), coal/biomass combustion (25.5% and 13.8%, respectively), fuel oil combustion (19.0% and 11.2%, respectively), road traffic (17.7% and 12.6%, respectively), and the metal industry (10.6% and 7.0%, respectively). Anthropogenic sources clearly contributed most to PM2.5 but natural sources contributed most to PM2.5–10.
Trombay; PM2.5; PM2.5–10; Black carbon; Metals; Positive matrix factorization