聊城市冬季PM2.5中多环芳烃来源解析及健康风险评估

Source Analysis and Health Risk Assessment of PAHs in PM2.5 During Winter in Liaocheng City

为研究聊城市冬季PM2.5中多环芳烃(PAHs)的浓度水平、来源及健康效应,于2017年1~2月对聊城市PM2.5中的14种PAHs进行分析,利用特征比值法和PCA-MLR模型对其来源及贡献率进行解析,并利用BaP当量浓度(BaPeq)和呼吸途径暴露PAHs引发癌症的风险(ILCR)模型进行健康风险评估.结果表明,聊城市冬季PM2.5中PAHs的平均质量浓度为(64.89±48.23)ng·m^-3,其中Fla、Pyr和Chry的浓度最高,占比分别为15.5%、12.8%和12.7%,且4环PAHs总质量浓度占比最高,春节前与烟火Ⅱ期比其他时期污染较重.PCA-MLR模型分析结果表明,聊城市冬季PM2.5中PAHs来源主要包括煤炭燃烧、生物质燃烧和机动车尾气.聊城市冬季TEQ平均值为(6.37±4.92)ng·m^-3,ILCR模型评估结果表明,成人的ILCR值高于儿童,二者的ILCR值均处于风险阈值内(10^-6~10^-4),表明聊城市冬季PM2.5具有潜在致癌风险.

To investigate the mass concentrations,sources,and health effects of polycyclic aromatic hydrocarbons (PAHs) in ambient particulate matter (PM) in Liaocheng City during winter,14 types of PAHs in PM2.5 were determined from January to February of 2017.The sources of the PAHs were analyzed by using diagnostics ratios and the principal component analysis (PCA)-multiple linear regression (MLR) model,and the health risk of PAHs was assessed by BaP equivalent concentrations (BaPeq ) and incremental lifetime cancer risk (ILCR).The results showed that the mass concentrations of PAHs in PM2.5 during winter were (64.89 ± 48.23) ng·m^-3, Fla,Pyr,and Chry were predominant species,accounting for 15.5%,12.8%,and 12.7% of the total concentrations of PAHs, respectively.Moreover,the ring distribution of the PAHs was dominated by four-ring PAHs.The pollution during the pre-Spring Festival and firework IIwere the most severe during the sampling period.The results of the PCA-MLR model suggested that PAHs originated mostly from coal burning,biomass burning,and vehicle emissions.The toxicity exposure index (TEQ) in Liaocheng City during winter was (6.37 ± 4.92) ng·m^-3.The results of the risk model revealed that the ILCR of adults was higher than that of children,and both groups of ILCR for winter were in the range of the risk threshold.This suggests that a potential risk in terms of inhalation PAH exposure for residents in Liaocheng City.