Sources of PM2.5-Associated PAHs and n-alkanes in Changzhou China

Polycyclic aromatic hydrocarbons (PAHs) and n-alkanes are important specific organic constituents in fine particulate matter (PM2.5). Seventy-five PM2.5 samples were collected Spring Changzhou, to investigate the concentrations sources of (C9–C40) PAHs. The average total PAHs (∑PAHs) (∑n-alkanes) 4.37 ± 4.95 ng/m3 252.37 184.02 ng/m3, ranging from 0.43 22.22 57.37 972.17 respectively. ∑n-alkanes ∑PAHs higher severely polluted days (PM2.5 ≥ 150 μg/m3) comparison other days. Up 85% four- five-ring compounds, middle-chain-length (C25–C35) most abundant species (80.9%). molecular distribution was characterized by odd-number carbon predominance (carbon preference index, CPI > 1), with a maximum centered at C27, C29, C31 revealing significant role biogenic sources. Principal component analysis suggested that contributed coal combustion (46.3%), followed biomass burning (16.0%), vehicular exhaust (10.3%). variation concentration different air mass transports not agreement change mass, indicating regional transport had impacts on characterization PM2.5. results our study can provide useful information for evaluating influence anthropogenic activities matters (n-alkanes PAHs).