重污染天气PM2.5中多环芳烃健康风险及预期寿命损失分析

Analysis of health risk and life expectancy loss of polycyclic aromatic hydrocarbons （PAHs） in PM2.5 under heavy polluted weather

目的了解2016年天津市重污染(AQI>200)天气下,PM2.5中多环芳烃健康风险及预期寿命损失。方法冬季采暖期对天津市红桥区和宝坻区大气进行采样,共159份样品,用气相色谱质谱联用仪对16种多环芳烃测定。参考美国环境保护署健康风险评价模型和已发表文献分析多环芳烃带来的健康风险及预期寿命损失。 结果AQI>200的天气PM2.5平均质量浓度最大值为0.588mg/m^3,超过国家标准二级浓度限值7.8倍;市区和市郊PM2.5中多环芳烃浓度均以苯并[b]荧蒽、和苯并[a]芘、荧蒽、芘为主,苯并[b]荧蒽含量最高,市郊高于市区,两者比较差异有统计学意义。市区和市郊多环芳烃总毒性等效浓度分别为9.237ng/m^3和28.039ng/m^3,均以苯并[a]芘占比最高;市郊致癌多环芳烃对成人及儿童产生的超额致癌风险分别为6.67×10^-6和3.00×10^-6均比市区(分别为2.18×10^-6和0.98×10^-6)大,但均处可接受水平;市郊对成人及儿童产生预期寿命损失分别为41.5min和13.6min比市区(分别为18.6min和6.1min)大。 结论重污染天气下,市郊环境PM2.5中多环芳烃造成预期寿命损失比市区高,提醒相关部门在制定风险管理政策时引起重视。

Objective To investigate the health risk and life expectancy loss due to premature mortality of polycyclic aromatic hydrocarbons (PAHs) in fine particulate matter under heavy pollution weather conditions (AQI>200) in Tianjin, 2016. Methods Atmospheric samples from Hongqiao and Baodi districts of Tianjin were collected during the heating period in winter. A total of 159 samples were collected and 16 PAHs were determined by gas chromatography-mass spectrometry. The health risk assessment model of the United States Environmental Protection Agency (EPA) and previously published literatures were referred to analyze the health risk and life loss due to premature mortality caused by PAHs. Results Under heavy pollution conditions (AQI>200), the maximum value of the average concentration of fine particulate matter was 0.588 mg/m^3, which was 7.8 times higher than that of the national standard level II limit. Meanwhile, the concentration of PAHs in suburban areas was higher than in urban areas. The main components of PAHs in PM 2.5 in both areas were benzo[b]fluoranthene, benzo[a]pyrene, fluoranthene and pyrene, and the content of benzo[b]fluoranthene was the highest. The total toxicity equivalent concentrations of PAHs in urban and suburban areas were 9.237 ng/m 3 and 28.039 ng/m^3, respectively, with benzo[a]pyrene accounting for the highest proportion in both areas. The excess carcinogenic risks of PAHs to adults and children in suburban areas were 6.67×10^-6 and 3.00×10^-6 , respectively. The life loss due to premature mortality in suburban areas was 41.5 min, which was larger than that in urban areas (13.6 min). Conclusion When weather conditions were under heavy pollution (AQI>200), the health risk and life expectancy loss due to premature mortality caused by PAHs in urban areas were higher than those in suburban areas, and relevant departments should pay attention to it when making risk management policies.