武汉市青山区PM2.5成分特征及慢性健康风险评估

目的调查武汉市青山区PM2.5成分污染特征,并评估其对人群的潜在健康风险。方法分析2016—2017年每月7日PM2.5浓度及成分数据,分析其特征,并应用模型对部分成分元素进行人群健康风险评估。结果2016—2017年PM2.5年均质量浓度为60.06μg/m3,超过标准限值(35μg/m3)。4种阴阳离子年均质量浓度17.80μg/m3,在PM2.5中占比31.40%,NO3-与SO42-之和占总离子70%以上,平均比值0.72,来源以煤、石油、天然气等化石燃料的燃烧为主;12种金属离子年均总质量浓度0.27μg/m3,携带的主要金属元素是Al、Pb、Mn,As、Cr超出环境空气质量标准中年平均限值;16种多环芳烃全年总浓度均值15.72 ng/m3,其中2016年BaP平均浓度1.32 ng/m3高于我国二级限值,2017年0.63 ng/m3低于限值。风险评估结果显示,PAHs和As的慢性非致癌和致癌效应的百分位数分布均相对较高,Mn的慢性非致癌风险的百分位数分布有少量偏高,Cr和Cd的致癌风险百分位数分布有少量偏高。结论近年来武汉市青山区空气质量污染情况有所减轻,但仍高于我国环境空气质量二级标准,PM2.5成分中部分元素慢性非致癌和致癌效应超过可接受水平,应进一步加强重视。

Composition characteristics and chronic health risk assessment of atmospheric PM2.5 pollution in Qingshan District of Wuhan

Objective To investigate the pollution characteristics and potential health risks of fine particulate matter(PM2.5)in Qingshan District,Wuhan.Methods The PM2.5 samples were collected in Qingshan District of Wuhan for 7 days every and each month from the year 2016 to 2017.The components were measured by inductively coupled plasma mass spectrometry(ICP-MS).The potential health risks were assessed based on the standard method recommended by the United States Environmental Protection Agency.Results The average annual mass concentration of PM2.5 was 60.06μg/m3,exceeding the ambient air quality standard of China.The average annual mass concentration of 4 water-soluble anions and cations was 17.80μg/m3,accounting for 31.40%of PM2.5.The sum of NO3-and SO42-accounted for more than 70%of the total ions with an average ratio of 0.72,and the source was mainly the combustion of fossil fuels such as coal,oil and natural gas.The average annual mass concentration of 12 metal elements in PM2.5 was 0.27μg/m3,with the main elements being Al,Pb,and Mn.The average concentration of As and Cr exceeded the annual average limit of ambient air quality standards.The annual average concentration of 16 types of PAHs was 15.72 ng/m3,of which the average BaP concentration was 1.32 ng/m3 in 2016,which was higher than the second-level limit in China,and 0.63 ng/m3 in 2017,which was lower than the limit.The risk assessment results showed that the percentile distribution of chronic non-carcinogenic and carcinogenic effects of both PAHs and As was relatively high,while Mn had certain chronic non-carcinogenic health risks,and Cr and Cd had certain carcinogenic risks.Conclusion In recent years,the air quality pollution in Qingshan District of Wuhan had been reduced,but it was still higher than the secondary air quality standard of China.The chronic non-carcinogenic and carcinogenic effects of some elements in PM2.5 exceeded acceptable levels,which should be further emphasized.