基于形态及生物可给性的汞污染场地概率风险 |
| |
引用本文: | 陈卓,张丹,吴志远,贾晓洋,夏天翔. 基于形态及生物可给性的汞污染场地概率风险[J]. 环境科学研究, 2021, 34(11): 2748-2756. DOI: 10.13198/j.issn.1001-6929.2021.07.11 |
| |
作者姓名: | 陈卓 张丹 吴志远 贾晓洋 夏天翔 |
| |
作者单位: | 北京市环境保护科学研究院,国家城市环境污染控制工程技术研究中心,污染场地风险模拟与修复北京市重点实验室,北京 100037 |
| |
基金项目: | 国家重点研发计划项目2018YFC1801006 |
| |
摘 要: | 为准确客观地评估汞污染场地的人体健康风险,克服当前土壤修复目标值过于保守的缺陷,对我国东北某大型汞化工废渣遗留场地进行详细环境调查,使用场地均匀设置的313个土壤样品(地表下0.5 m)的总汞含量检出数据、9个样品的零价汞含量占比数据、30个样品的胃肠可给态汞含量占比数据进行蒙特卡洛概率模拟,使用参数的概率模拟值进行汞经口摄入和气态呼吸吸入的人体健康风险和修复目标值的概率预测.结果表明:①场地的总汞含量在空间上差异明显,变化范围为0.002~579.14 mg/kg,变异系数为3.88,且主要集中在0~2.5 m;零价汞含量占比平均为15.2%±6.4%,与土壤总汞含量呈显著对数负相关(R2=0.784 5);胃肠可给态汞含量占比平均为2.74%±2.81%,与总汞含量不具有显著相关关系.②气态呼吸吸入是该场地主要的人体健康风险来源,占总风险值的90%,风险不可忽略(危害商大于1)的概率为5.00%;经口摄入的风险不可忽略(危害商大于1)的概率为0.15%.③基于零价汞、胃肠可给态汞含量的修复目标值累积概率分布的5%上分位数为53.8 mg/kg,相应的修复面积分别为5 427.9 m2,显著低于以GB 36600-2018《土壤环境质量建设用地土壤污染风险管控标准(试行)》中第一类用地风险筛选值(8 mg/kg)为修复目标值而确定的修复面积(37 057.6 m2);零价汞含量占比与儿童体重是影响修复目标值最主要的参数,对修复目标值的不确定性贡献率分别为-78%和42%.研究显示,基于土壤汞形态及生物可给性的概率风险评估能更为准确地显示污染场地的人体健康风险及主要风险途径,也能有效降低相应的修复目标值,避免对场地过度修复.
|
关 键 词: | 零价汞 胃肠可给态 蒙特卡洛 健康风险 |
收稿时间: | 2021-04-27 |
Probability Risk of Mercury Contaminated Site Based on Species and Bioaccessibility |
| |
Affiliation: | Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites, National Engineering Research Center of Urban Environmental Pollution Control, Beijing Municipal Research Institute of Environmental Protection, Beijing 100037, China |
| |
Abstract: | In order to accurately and objectively assess the human health risks of mercury-contaminated sites and overcome the shortcomings of current soil control values that are too conservative, this study conducted a detailed environmental investigation on a large mercury chemical waste site in northeast China. Monte Carlo probabilistic simulations were performed for total mercury data from 313 soil samples (sampled at a depth of 0.5 m), zero-valent mercury content data from 9 soil samples and gastrointestinal availability data for mercury from 30 soil samples at the site. Probabilistic predictions of human health risks and remediation target values for oral ingestion and gaseous inhalation at the site were made using the parameter probabilistic simulation values. The results show that: (1) The total mercury content of the site varied spatially from 0.002 to 579.14 mg/kg with a variable coefficient of 3.88 and was mainly concentrated in the 0-2.5 m. The average content of zero-valent mercury was 15.2%±6.4%, showing a significant negative logarithmic relationship with the total mercury concentration (R2=0.7845). The average content of gastrointestinal administrable mercury was 2.74%±2.81%, which was not significant correlated with the total mercury. (2) Inhaled gas was the main source of human health risks at the site, accounting for 90% of the total risk value, with a 5% probability of non-negligible (risk quotient >1). The oral intake route had a 0.15% probability of non-negligible (risk quotient >1). (3) The combined risk control remediation target value based on zero-valent mercury and gastrointestinal bioavailable mercury content was 53.8 mg/kg (5% quantile), with a corresponding remediation area of 5, 427.9 m2, which was significantly lower than the remediation area (37, 057.6 m2) determined using the risk screening value (8 mg/kg) of Soil Environment Quality Risk Control Standard for Soil Contamination of Development Land (GB 36600-2018) as the remediation target value for the construction site category 1 site. The proportion of zero-valent mercury and the weight of children were the most important parameters affecting the remediation target values, contributing -78% and 42% to the uncertainty of the remediation target values, respectively. The research showed that the probability risk assessment based on mercury species and bioaccessibility can more accurately assess the risks and main risk pathways of contaminated sites, and can also effectively lower the corresponding restoration target values and avoid over remediation. |
| |
Keywords: | |
本文献已被 万方数据 等数据库收录! |
| 点击此处可从《环境科学研究》浏览原始摘要信息 |
|
点击此处可从《环境科学研究》下载免费的PDF全文 |
|