宁东基地大气PAHs污染特征及呼吸暴露风险

Pollution characteristics and inhalation exposure risk of atmospheric PAHs in Ningdong Base

利用主动观测技术对宁东能源化工基地大气PM2.5、PM 1.0和气相中的PAHs浓度水平、族谱特征、时空分布及来源进行研究,并基于该观测数据对居民呼吸暴露健康风险进行评估.结果表明,宁东基地大气PM2.5、PM 1.0及气相中∑1 6PAHs浓度范围分别为:17.95~325.12ng/m、12.66~311.96ng/m和26.33~97.88ng/m,年均浓度分别为(99.42±117.48)ng/m、(78.88±100.58)ng/m和(57.89±47.39)ng/m.宝丰基地冬夏季大气PM2.5、PM 1.0和气相中∑1 6PAHs浓度水平均明显高于英力特;宝丰和英力特基地冬季大气PM2.5、PM 1.0中∑1 6PAHs浓度水平均明显高于夏季浓度.宁东基地大气中∑1 6PAHs的浓度水平要高于国内外其他城市,大气PAHs污染较为严重.源解析表明夏季宁东基地PAHs的主要排放源是工业煤燃烧和机动车尾气,冬季则主要来自工业煤燃烧和木材、薪柴等生物质燃烧排放.宁东基地人群暴露于大气PAHs可能会造成平均冬季每百万人中约有33~2628人罹患癌症,夏季每百万人中约有11~834人罹患癌症的风险.

The active sampling technique was adopted to investigate the concentration levels,profiles and spatial temporal distribution as well as the source apportionments of atmospheric PAHs in PM2.5,PM1.0 and gas phase.The inhalation exposure risk of local population to atmospheric PAHs was evaluated based on atmospheric observation data in Ningdong Base.The ranges of atmospheric concentration levels of∑16PAHs for PM2.5,PM1.0 and gas phase were 17.95~325.12ng/m^3,12.66~311.96ng/m3 and26.33~97.88ng/m^3 respectively,and the average annual concentrations were(99.42±117.48)ng/m^3,(78.88±100.58)ng/m^3 and(57.89±47.39)ng/m^3,respectively.The spatial distributions of atmospheric PAHs levels for PM2.5,PM1.0 and gas phase in Baofeng site were significantly higher than that in Yinglite site for both winter and summer.The seasonal pollution characteristics indicated that∑16PAHs concentration levels were significantly higher in Baofeng site than that in Yinglite site not only in winter but in summer.Comparison of atmospheric PAHs levels in Ningdong Base with that of other cities or regions worldwide,which exhibited higher concentration levels,suggesting atmospheric PAHs pollution was more serious in Ningdong Base.Source apportionment indicated that the main emission sources of PAHs in Ningdong Base were industrial coal combustion and motor vehicle exhaust in summer,while industrial coal combustion and biomass burning in winter.The average excess inhalation cancer risks(ECR)due to human exposure to atmospheric PAHs were about 33~2628 cases per million people in Ningdong Base in winter,while 11~834 cases per million people in summer.