Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun, 130021, PR China; College of New Energy and Environment, Jilin University, Changchun, 130021, PR China.
Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun, 130021, PR China; College of New Energy and Environment, Jilin University, Changchun, 130021, PR China.
Environ Res. 2022 Nov;214(Pt 1):113772. doi: 10.1016/j.envres.2022.113772. Epub 2022 Jul 2.
Toxic heavy metals pollution in urban soil has become a major global issue due to its adverse effects on the environment and human health. In this paper, 26 soil samples were analyzed to assess the speciation, bioavailability and human health risk of Arsenic (As), Mercury (Hg), Lead (Pb) and Cadmium (Cd) in urban soils of a heavy industrial city in NE China by using a Monte Carlo simulation approach. The results showed that As, Hg, Pb and Cd concentrations in the soil all exceed the corresponding background value of study area. Mercury displays the highest value of geo-accumulation index (Igeo), followed by Cd, Pb and As. The pollution load index (PLI) value (>2) indicates a moderate pollution level in the study area. The chemical speciation of HMs mainly exists in residual fraction except Cd. The probabilistic health risk assessment demonstrated that the mean values of Total Carcinogenic Risk (TCR) and Hazard Index (HI) calculated with total concentration are at the unacceptable level, with a higher risk to children than adults. However, the mean values calculated with bioavailable fraction are all within the acceptable level. The mean value of TCR and HI obtained by bioavailable fraction is about 96% and 95% lower than that obtained by total concentration, respectively. Thus, this study suggested that the bioavailable fraction of HMs is a more reliable parameter for health risk assessment, while the total concentration of HMs can overestimate the true risk. The results of this study provide some insight into the speciation, bioavailability and health risks of toxic heavy metals in urban soils in those heavy industrial cities.
城市土壤中的有毒重金属污染已成为一个全球性的重大问题，因为它对环境和人类健康有不利影响。在这项研究中，采用蒙特卡罗模拟方法，分析了中国东北地区一个重工业城市的 26 个土壤样本，评估了砷（As）、汞（Hg）、铅（Pb）和镉（Cd）在城市土壤中的形态、生物可利用性和人体健康风险。结果表明，土壤中 As、Hg、Pb 和 Cd 的浓度均超过研究区相应的背景值。汞的地积累指数（Igeo）最高，其次是 Cd、Pb 和 As。污染负荷指数（PLI）值（>2）表明研究区处于中度污染水平。重金属的化学形态主要以残渣态存在，除 Cd 外。概率健康风险评估表明，用总浓度计算的总致癌风险（TCR）和危害指数（HI）的平均值处于不可接受的水平，对儿童的风险高于成人。然而，用生物可利用分数计算的平均值均在可接受范围内。用生物可利用分数计算的 TCR 和 HI 的平均值分别比用总浓度计算的平均值低约 96%和 95%。因此，本研究表明重金属的生物可利用分数是健康风险评估的更可靠参数，而重金属的总浓度可能会高估真实风险。本研究结果为了解这些重工业城市中城市土壤中有毒重金属的形态、生物可利用性和健康风险提供了一些见解。
