The impact of heating season factors on eight PM_(2.5)-bound polycyclic aromatic hydrocarbon (PAH) concentrations and cancer risk in Beijing

摘要

In 2015, 443 atmospheric PM2.5 samples were collected at five sampling sites in Beijing. The concentrations of PM2.5-bound PAH(8) (Chr, BaA, BbF, BkF, B[a]P, DBA, BghiP, and IND) were determined via high performance liquid chromatography (HPLC). The annual concentration of PM2.5-bound PAH(8), lifetime cancer risk, and the increasing value due to heating season factors (heating and meteorological conditions) were analyzed. The results showed that the sum concentration of PM2.5-bound PAH(8) during heating season was 72.6 ng/m(3) and higher than the non-heating season concentration of 4.77 ng/m(3). The annual concentration was 10.6 ng/m(3), which increased 5.83 ng/m(3) due to heating season factors. The B[a]P annual concentration was 1.67 ng/m(3) and higher than the limit of 1 ng/m(3), which was 152 times that of non-heating season. Diesel vehicles and gasoline vehicles were the primary PAH(8) sources during non-heating season, while the mixed sources of diesel vehicles, gasoline vehicles, and combustion were the dominant PAH(8) sources during heating season. The most significant health hazard pollutant was B[a]P, which accounted for 72%, 74%, and 69% of the B[a]P equivalent concentration (B[a]Peg) of PAH(8) during heating season, non-heating season, and throughout 2015, respectively. The lifetime cancer risk was 2.67 x 10(-6), which increased 1.36 x 10(-6) due to heating season factors. Therefore, heating season factors nearly doubled the annual concentration of PM2.5-bound Sigma PAH(8) and lifetime cancer risk. The results indicated that to protect human health, it is very important to control PM2.5-bound Sigma PAH(8) emissions during heating season, especially B[a]P emissions. (C) 2019 Elsevier B.V. All rights reserved.