典型滴滴涕废弃生产场地污染土壤的人体健康风险评估研究

摘要

Site investigation, human health risk assessment and derivation of recommended soil remediation goal were conducted in suspected DDT polluted area of a former DDT manufacturing site in China. It was found that the chemicals of concern (COCs) in the area around the wastewater treatment tank of the plant were mainly p, p'-DDT, p, p'-DDD, p, p'-DDE, 1,4-dichlorobenzene, chloroform and chlorobenzene. In the soil on the north and east sides of the tank vertical translocation of COCs was obvious, whereas in other parts of the site COCs were only found in the 0 ~ 50 cm soil layer. Of the first five COCs, carcinogenic risk was beyond 10-6. At some points non-carcinogenic hazard index of p, P' DDT and chlorobenzene exceeded 1. Uncertainty analysis shows that soil ingestion and dermal contact accounted for more than 98% of the total risk of semi-volatile organic compounds such as p, p'-DDT, p, p'-DDD and p, p'-DDE, whereas, indoor air inhalation for more than 99% of the total risk of volatile organic compounds such as chlorobenzene, 1 ,4-dichlo-robenzen and chloroform. Soil particle density, soil bulk density, and soil water content were sensitive parameters. The recommended soil remediation goal of p, p'-DDT, p, p'-DDD, p, p'-DDE, chlorobenzene, 1,4-dichlorobenzen, and chloroform are 5.84, 6. 19, 4.36, 36.2, 0.55, and 0.02 mg kg-1, respectively.%对我国典型滴滴涕(DDT)废弃生产场地的疑似重污染区进行环境调查、污染土壤人体健康风险评估和土壤修复建议目标值计算.结果表明,该场地污水处理池周边的关注污染物主要为p,p’-DDT、p,p’-DDD、p,p'-DDE、1,4-二氯苯、氯仿和氯苯,临近污水处理池北侧和东侧的区域土壤中污染物垂向迁移明显,其他区域土壤污染物主要分布于0～50 cm土层.前5种关注污染物的致癌风险均超过10-6,部分点位p,p’-DDT和氯苯的非致癌危害指数大于1.不确定性分析表明,半挥发性有机物p,p’-DDT、p,p’-DDD和p,p’-DDE经口腔摄人土壤和皮肤接触土壤暴露途径对总风险的贡献率超过98％,挥发性有机物氯苯、1,4-二氯苯和氯仿经吸入室内空气暴露途径对总风险的贡献率高达99％以上.土壤颗粒密度、土壤容重和土壤含水率是敏感参数.p,p’-DDT、p,p’-DDD、p,p’-DDE、氯苯、1,4-二氯苯和氯仿的土壤修复建议目标值分别为5.84、6.19、4.36、36.2、0.55和0.02 mgkg-1.