PAHs in PM2.5 in Zhengzhou: concentration, carcinogenic risk analysis, and source apportionment

• Published in: Environmental monitoring and assessment 2014-11, Vol.186 (11), p.7461-7473
• Main Authors: Wang, Jia, Geng, Ning Bo, Xu, Yi Fei, Zhang, Wen Ding, Tang, Xiao Yan, Zhang, Rui Qin
• Format: Article
• Language: English
• Subjects: Adult; Air Pollutants - analysis; Air sampling; Airborne particulates; Atmospheric Protection/Air Quality Control/Air Pollution; Cancer; Carcinogens; Carcinogens - analysis; China; Coal - analysis; Earth and Environmental Science; Ecology; Ecotoxicology; Emissions; Environment; Environmental Management; Environmental Monitoring; Health risk assessment; Health risks; Human exposure; Humans; Industrial plant emissions; Inhalation; Inhalation Exposure - analysis; Inhalation Exposure - statistics & numerical data; Monitoring/Environmental Analysis; Particulate matter; Particulate Matter - analysis; Pollution; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; Principal components analysis; Residential areas; Risk analysis; Risk Assessment; Seasonal variations; Seasons; Studies; Toxicity; Vehicle emissions; Vehicle Emissions - analysis; Winter
• ISSN: 0167-6369; 1573-2959
• DOI: 10.1007/s10661-014-3940-1

Ambient air samples were collected at two different locations between 2011 and 2012 in Zhengzhou, China in order to assess the concentration level, health risks, as well as the sources of polycyclic aromatic hydrocarbons (PAHs) in particulate matter (PM 2.5 ). The mean annual levels of PM 2.5 observed at industry site and residential site were 172 ± 121 and 160 ± 72 μg m −3 , respectively, which were about five times the annual value of proposed PM 2.5 standard (35 μg m −3 ) in China. The PM 2.5 in all daily samples ( n  = 47) exceeds the proposed PM 2.5 standard in China (75 μg m −3 ) at both industrial and residential sites. Seasonal variations of PM 2.5 showed a clear trend of winter > autumn > spring > summer at both sites. The total concentrations of 16 PM 2.5 -associated PAHs ranged from 61 ± 51 to 431 ± 281 and 38 ± 25 to 254 ± 189 ng m −3 , with mean value of 176 ± 233 and 111 ± 146 ng m −3 at industry and residential sites, respectively. The major species were fluoranthene, pyrene, chrysene, benzo[ b ]fluoranthene and benzo[ k ]fluoranthene, and the concentration levels of PAHs in PM 2.5 were higher in winter than those of other seasons at both sites. The annual mean values of toxicity equivalency concentrations of ∑ 16 PAHs in PM 2.5 were 22.8 and 13.5 ng m −3 in industry and residential area, respectively. In this study, the risk level of adult citizens through inhalation exposure to PAHs was calculated. The average estimates of lifetime inhalation cancer risks were approximately 8.9 × 10 −7 and 6.3 × 10 −7 for industry and residential sites, respectively. The main sources of 16 PAHs from both diagnostic ratios and principle component analysis identified as vehicular emissions and coal combustion.