Multi-source apportionment of polycyclic aromatic hydrocarbons using end-member mixing approach

A new approach to identify multiple sources of polycyclic aromatic hydrocarbons (PAHs) and to evaluate the source contributions to the atmospheric deposition of particulate PAHs is proposed. The approach is based on differences in the concentrations of the sums of PAHs with the same molecular weight among the different PAH sources. Data on PAH accumulation in snow, as well as source profiles, were used for calculations. The contributions of an aluminum production plant, oil-fired central heating boilers, and residential wood and coal combustion were calculated using linear mixing models. The concentrations of PAH pairs such as benzo[b]fluoranthene+benzo[k]fluoranthene and benzo[g,h,i]perylene+indeno[1,2,3-c,d]pyrene normalized to benzo[a]anthracene+chrysene were used as tracers in the mixing equations. The results obtained using ratios of PAH pairs were compared with those obtained using molecular diagnostic ratios such as benzo[a]anthracene/chrysene and benzo[g,h,i]perylene/indeno[1,2,3-c,d]pyrene. It was shown that the results obtained using diagnostic ratios as tracers are less reliable than the results obtained using the ratios of the sums of PAHs.