State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
College of Environmental Sciences & Engineering, Beijing Forestry University, Beijing 100083, China.
Int J Environ Res Public Health. 2022 Oct 12;19(20):13120. doi: 10.3390/ijerph192013120.
Taihu Lake is the third-largest freshwater lake in eastern China. The contamination of heavy metals (HMs) in Taihu Lake resulting from rapid economic development and population growth has raised significant concerns in recent years. In this study, the contents and spatial distributions of eight typical HMs (Hg, Cr(VI), As, Cd, Cu, Ni, Pb, and Zn) in the fresh surface water and sediments from Taihu Lake were investigated. The potential ecological and health risks posed by HMs were evaluated using multiple assessment methods. Risk quotients were used to assess the ecological risks of HMs, and chronic risk quotients of Cu, Ni, and Pb (>1.0) were found in the surface water of Taihu Lake. According to the geo-accumulation index (I) and pollution load index (PLI) values, the lake sediments exhibited moderate risks of Cd and Hg. In general, the sediments were moderately contaminated by HMs based on the average risk index (RI < 300). Spatially, a high ecological risk posed by the HMs existed in the sediments of northern Taihu Lake (RI > 300), while the sediments in the southwestern and eastern regions had moderate risk levels. The non-carcinogenic risk levels of Hg, Cd, Cu, and Zn were acceptable based on the exposure characteristics of residents living around Taihu Lake. The carcinogenic risk levels of Cr(VI), As, Pb, and Ni through drinking water were acceptable. However, the ingestion of Cr(VI), As, and Ni through drinking water and fish consumption may pose certain health risks. Therefore, the levels of toxic metals, in particular, Cr(VI), As, and Ni, in edible organisms should be monitored periodically and controlled to alleviate the potential carcinogenic risks through food ingestion. Our work provides valuable information concerning the ecological risk distribution of HMs in Taihu Lake, which is essential for protecting the safety of aquatic organisms and human health and minimizing HM pollution in the lake.
太湖是中国东部第三大淡水湖。近年来，随着经济的快速发展和人口的增长，太湖重金属（HMs）的污染引起了人们的高度关注。本研究调查了太湖新鲜地表水和沉积物中八种典型 HMs（Hg、Cr(VI)、As、Cd、Cu、Ni、Pb 和 Zn）的含量和空间分布。采用多种评价方法评价了 HMs 的潜在生态和健康风险。风险商数用于评估 HMs 的生态风险，发现太湖地表水 Cu、Ni 和 Pb 的慢性风险商数（>1.0）。根据地质累积指数（I）和污染负荷指数（PLI）值，湖泊沉积物中 Cd 和 Hg 具有中等风险。总体而言，根据平均风险指数（RI<300），沉积物中 HMs 中度污染。从空间上看，北部太湖沉积物中 HMs 存在较高的生态风险（RI>300），而西南部和东部地区沉积物风险水平适中。根据太湖周边居民的暴露特征，Hg、Cd、Cu 和 Zn 的非致癌风险水平是可以接受的。Cr(VI)、As、Pb 和 Ni 通过饮用水摄入的致癌风险水平是可以接受的。然而，通过饮用水和鱼类摄入 Cr(VI)、As 和 Ni 可能会对健康造成一定的风险。因此，应定期监测食用生物体内有毒金属（尤其是 Cr(VI)、As 和 Ni）的水平，并加以控制，以减轻通过食物摄入产生的潜在致癌风险。本研究为太湖 HMs 的生态风险分布提供了有价值的信息，对于保护水生生物的安全和人类健康，减少湖泊中的 HM 污染具有重要意义。
