典型多环芳烃污染场地土壤健康风险评估及参数敏感性分析

Health risk assessment and sensitivity analysis of parameters in typical polycyclic aromatic hydrocarbons contaminated sites

以某典型多环芳烃污染场地为研究对象,对土壤中USEPA优控的16种多环芳烃进行调查和风险评估,研究不同污染因子的主要暴露途径以及评估过程中关键参数的敏感性。结果表明:场地土壤中苯并[a]芘、萘、苯并[a]蒽、苯并[b]荧蒽、二苯并[a,h]蒽存在不同程度的超标,最大超标倍数依次为39.91、11.44、0.07、0.20、1.00。风险评估结果显示,苯并[a]芘、萘、苯并[a]蒽、苯并[b]荧蒽、二苯并[a,h]蒽的风险水平均超过可接受风险水平1.00×10^(-6),其中萘的主导暴露途径为吸入室内空气中气态污染物,苯并[a]芘、苯并[a]蒽、苯并[b]荧蒽、二苯并[a,h]蒽的主导暴露途径为经口摄入土壤颗粒物和皮肤接触土壤颗粒物,后续应根据污染物的主导暴露途径,有针对性地采取管控措施。参数敏感性分析结果表明,萘的敏感性参数主要为地基裂隙中空气体积比、土壤颗粒密度、土壤有机质含量、室内空气交换速率和室内空间体积与气态污染物入渗面积之比;苯并[a]芘、苯并[a]蒽、苯并[b]荧蒽、二苯并[a,h]蒽的敏感性参数为儿童暴露期、成人暴露期、儿童平均体重、儿童每日摄入土壤量等,未来土壤污染风险管理中应根据污染物特性,合理确定评估参数的取值,准确评价地块风险水平。

Taking a typical polycyclic aromatic hydrocarbon contaminated site as the research object,investigation and risk assessment of 16 types of polycyclic aromatic hydrocarbons in the soil that USEPA optimally controls were carried out,and the main exposure pathways of different pollution factors and the sensitivity of key parameters in the evaluation process were studied.The results showed that:benzo[a]pyrene,naphthalene,benzo[a]anthracene,benzo[b]fluoranthene,and dibenzo[a,h]anthracene exist to varying degrees in the site soil.The maximum exceeding multiples were 39.91,11.44,0.07,0.20,and 1.00 in order.The risk assessment results showed that the risk levels of benzo[a]pyrene,naphthalene,benzo[a]anthracene,benzo[b]fluoranthene,and dibenzo[a,h]anthracene exceeding the acceptable risk level of 1.00×10^(-6),the main exposure route of naphthalene was the inhalation of gaseous pollutants in indoor air,benzo[a]pyrene,benzo[a]anthracene,benzene the main exposure pathways of[b]fluoranthene and dibenzo[a,h]anthracene were oral ingestion of soil particulate matter and skin contact with soil particulate matter.Follow-up should be targeted based on the leading exposure pathway of pollutants take control measures locally.The parameter sensitivity analysis results showed that the sensitivity parameters of naphthalene were mainly the air volume ratio in the foundation cracks,soil particle density,soil organic matter content,indoor air exchange rate,and the ratio of indoor space volume to gaseous pollutant infiltration area;benzo the sensitivity parameters of[a]pyrene,benzo[a]anthracene,benzo[b]fluoranthene,dibenzo[a,h]anthracene were children′s exposure period,adult exposure period,and children average weight,daily intake of soil by children,etc.,in the future soil pollution risk management should be based on the characteristics of pollutants,rationally determine the value of the evaluation parameters,and accurately evaluate the risk level of the plot.