Reconstructing Primary and Secondary Components of PM2.5 Composition for an Urban Atmosphere

TLDR: In this paper, a total 360 PM25 samples were collected from six sampling sites for summer and winter seasons in Kanpur city, India and the collected PM25 mass was subjected to chemical speciation for: (1) ionic species (NH+ 4, SO2-4, NO 3, and Cl 3), (2) carbon contents (EC and OC), and (3) elemental contents (Ca, Mg, Na, K, Al, Si, Fe, Ti, Mn, V, Cr, Ni, Zn, Cd, Pb,

Abstract: Total 360 samples (of 8 h each) of PM25 were collected from six sampling sites for summer and winter seasons in Kanpur city, India The collected PM25 mass was subjected to chemical speciation for: (1) ionic species (NH+ 4, SO2– 4, NO– 3, and Cl–), (2) carbon contents (EC and OC), and (3) elemental contents (Ca, Mg, Na, K, Al, Si, Fe, Ti, Mn, V, Cr, Ni, Zn, Cd, Pb, Cu, As, and Se) Primary and secondary components of PM25 were assessed from speciation results The influence of marine source to PM25 was negligible, whereas the contribution of crustal dust was significant (10% in summer and 7% in winter) A mass reconstruction approach for PM25 could distinctly establish primary and secondary components of measured PM25 as: (1) Primary component (27% in summer and 24% in winter): crustal, elemental carbon, and organic mass, (2) Secondary component (45% in summer and 50% in winter): inorganic and organic mass, and (3) others: unidentified mass (27% in summer and 26% in winter) The secondary inorganic