郑州市高新区大气VOCs源解析及风险评估

Source Apportionment and Risk Assessment of Ambient Volatile Organic Compounds from the High-tech Zone in Zhengzhou

为探究郑州市高新区环境大气中挥发性有机物(VOCs)的来源及潜在危害,通过罐采样-GC-MS/FID对样品进行采集分析,采用正交矩阵因子解析(PMF)模型及风险评价方法对VOCs来源及潜在危害进行研究。源解析结果显示,工业溶剂使用、机动车尾气、燃煤及生物质燃烧源是高新区VOCs主要排放源,其对VOCs贡献率依次为28.11%、27.58%及19.89%;其中溶剂涂料使用和植物排放源对臭氧生成潜势(OFP)贡献较大,分别为30.08%和30.42%。风险评估结果表明,高新区VOCs的OFP为174.18μg/m3,其中芳香烃和烯炔烃分别占37.33%和36.03%,OFP贡献大的物种为异戊二烯(23.31%)、间/对-二甲苯(11.77%)、丙酮(7.64%)、甲苯(6.71%)及1-丁烯(6.19%)。高新区环境空气中VOCs非致癌风险值(HI)在2.67×10-13.37×10-1之间,均值为3.03×10-1,低于美国环保署(USEPA)规定值1,其中苯、二氯甲烷、四氯化碳及三氯乙烯的HI值较高,其HI值在2.20×10-21.33×10-1之间;致癌风险值(Risk)为6.35×10-5,其中1,2-二氯乙烷、四氯化碳、苯及氯乙烯均高于USEPA限值(1×10-6),但未高于美国职业安全与健康署(OSHA)可承受的致癌风险值(1×10-3),说明对于长期暴露外界人群仍存在一定的致癌风险,危害人体健康。今后亟需加强溶剂使用、机动车尾气及燃烧源的管控。

To explore the sources and potential hazards of volatile organic compounds(VOCs)emitted from the atmosphere of the high-tech development zone in Zhengzhou,samples were collected and analyzed through using canisters and GCMS/FID system.The source apportionment and potential hazards of VOCs were analyzed and discussed with the positive matrix factorization(PMF)model and risk evaluation method in this study,respectively.The results of source analysis showed that industrial solvent use,vehicle exhaust,coal burning and biomass combustion were the main emission sources of VOCs in the high-tech zone,and their contribution rates to VOCs were 28.11%,27.58%and 19.89%,respectively.Among them,the contribution of solvent use and plant emission were significant to the potential of ozone formation(OFP),which were 30.08%and 30.42%respectively.Risk assessment results showed that the ozone formation potential(OFP)of VOCs in the hightech zone was 174.18μg/m3,among which the aromatic hydrocarbon and alkyne accounted for 37.33%and 36.03%,respectively.The species that OFP mainly contributed were isoprene(23.31%),m/p-xylene(11.77%),acetone(7.64%),toluene(6.71%)and 1-butene(6.19%).The non-carcinogenic risk(HI)of VOCs in the ambient air of high-tech zone were2.67×10-13.37×10-1,and the mean value was 3.03×10-1,which was lower than the environmental protection agency(USEPA)prescribed value,for 1.Among them,the HI value of benzene,methylene chloride,carbon tetrachloride and trichloroethylene were higher,and the HI value was 2.20×10-21.33×10-1.The carcinogenic risk(Risk)value was 6.35×10-5,and except that the carcinogenic index of 1,1,2,2-tetrachloroethane and tetrachloroethylene were not exceeded the Risk value(1×10-6)of USEPA,vinyl chloride,benzene,carbon tetrachloride and 1,2-dichloroethane were all higher than the carcinogenic risk value of USEPA,which indicated that there was a certain carcinogenic risk for people exposed to the outdoor environment for a long time,and damaged to the human health.Therefore,it is necessary to control the sources emissions of the solvent use,vehicle exhaust,coal and biomass combustion in the future.