Chemical characterization and source apportionment of PM1 and PM2.5 in Tianjin, China: Impacts of biomass burning and primary biogenic sources

The submicron particulate matter(PM) and fine particulate matter(PM) are very important due to their greater adverse impacts on the natural environment and human health. In this study, the daily PMand PMsamples were collected during early summer 2018 at a sub-urban site in the urban-industrial port city of Tianjin, China. The collected samples were analyzed for the carbonaceous fractions, inorganic ions, elemental species, and specific marker sugar species. The chemical characterization of PMand PMwas based on their concentrations, compositions, and characteristic ratios(PM/PM, AE/CE, NO~-/SO, OC/EC, SOC/OC, OM/TCA, K~+/EC, levoglucosan/K +, V/Cu, and V/Ni). The average concentrations of PMand PMwere 32.4 μg/m and 53.3 μg/m~3, and PMconstituted 63% of PMon average. The source apportionment of PMand PMby positive matrix factorization(PMF) model indicated the main sources of secondary aerosols(25% and 34%), biomass burning(17% and 20%), traffic emission(20% and 14%), and coal combustion(17% and 14%). The biomass burning factor involved agricultural fertilization and waste incineration. The biomass burning and primary biogenic contributions were determined by specific marker sugar species. The anthropogenic sources(combustion, secondary particle formation, etc) contributed significantly to PMand PM, and the natural sources were more evident in PM. This work significantly contributes to the chemical characterization and source apportionment of PMand PMin near-port cities influenced by the diverse sources.