基于土壤汞形态归趋的健康风险评估方法  

Health Risk Assessment Method Based on Mercury Fate and Transport in Soil

作　　者：雷国龙 付全凯 姜林[2,3,4] 郑瑞 张瑞环 钟茂生 张丽娜[2,3,4] LEI Guolong;FU Quankai;JIANG Lin;ZHENG Rui;ZHANG Ruihuan;ZHONG Maosheng;ZHANG Lina(Capital Normal University,Beijing 100045,China;Beijing Municipal Research Institute of Environmental Protection,Beijing 100037,China;National Engineering Research Center for Urban Environmental Pollution Control,Beijing 100037,China;Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites,Beijing 100037,China)

机构地区：[1]首都师范大学,北京100045 [2]北京市环境保护科学研究院,北京100037 [3]国家城市环境污染控制工程技术研究中心,北京100037 [4]污染场地风险模拟与修复北京市重点实验室,北京100037

出　　处：《环境科学研究》2020年第3期728-735,共8页Research of Environmental Sciences

基　　金：国家重点研发计划“场地土壤污染成因与治理技术”重点专项（No.2018YFC1803001,2018YFC1801004,2018YFC1800700)~~

摘　　要：土壤汞污染是一个全球性关注问题,矿产资源开采、化工生产和燃煤发电等均造成了不同程度的土壤汞污染,合理评估汞污染场地的健康风险是场地开发再利用的关键.对土壤中汞的形态归趋研究总结表明,由于汞的特殊物理化学性质,并受土壤等环境因素的影响,导致其在土壤中具有复杂的化学形态和变化过程.汞在土壤中的不同化学形态归趋对其毒性效应、生物有效性和暴露途径产生显著影响.基于土壤汞总量的风险评估方法忽略了土壤中不同化学形态汞对毒性、生物有效性和暴露途径的影响,导致高估土壤汞污染的健康风险.针对基于土壤汞总量的风险评估存在的问题,提出了基于土壤汞形态归趋的土壤汞污染健康风险评估理论,并构建基于土壤汞形态归趋-有效剂量-健康效应的土壤汞污染的精细化风险评估技术体系框架:①土壤不同形态汞的测定与表征方法;②汞形态归趋预测模型;③暴露分析与暴露量计算;④有效剂量(生物可给性或生物有效性)测定;⑤风险表征;⑥基于不同形态汞的场地土壤污染风险筛选值和修复目标制定.该方法体系从理论上解决了传统基于土壤汞总量的风险评估方法存在的问题,实际应用中面临的主要问题和今后重点发展方向:①研发可商业化的土壤汞化学物组分分析仪及土壤汞蒸气的原位测定方法;②结合中国场地土壤特点,开展土壤中汞的形态归趋模拟的模型研究,弥补现阶段土壤汞化合物形态分析方法的欠缺;③研发和建立土壤汞的生物可给性和有效性的标准测试方法技术;④本土化的土壤汞筛选值的确定.Mercury(Hg)contamination in soil is a global problem.Mining,chemical industry and coal power have caused different levels of mercury contamination in soil.It is a great challenge to assess the health based risk of Hg-contaminated site due to its special physical and chemical properties.Hg has different chemical species and forms in soil,which greatly influence the toxicity,bioavailability and exposure pathways of Hg in soil.Therefore,the existing regulatory risk assessment method based on the total amount of Hg in soil in general is too conservative by ignoring the effects of different species and forms of Hg on the toxicity,bioavailability and exposure pathways.A risk assessment framework and method is proposed based on the fate and transport-effective exposure dose-health effect:(1)characterization of different Hg species in soil;(2)the fate and transport model of Hg;(3)exposure analysis;(4)bioavailability and bioaccessibility test;(5)risk characterization.This method overcomes the conservativeness of the existing regulatory approach based on the total amount of Hg in soil.The paper further discusses the future development for the practical use of the method:(1)development of lab analytical methods for Hg speciation for commercial uses and in-situ soil Hg vapor measurement;(2)development of multimedia Hg fate and transport model;(3)standardizing Hg bioavailability and bioaccessibility test methods;and(4)development of soil screening levels based on the chemical speciation of Hg and the soil conditions in China.

关 键 词：土壤汞污染 形态归趋 生物有效性 健康风险评估 

分 类 号：X53[环境科学与工程—环境工程]