Huang Hong-Wei, Xiao He, Wang Dun-Qiu, Xi Bei-Dou, Sun Xiao-Jie, Li Jie-Yue, Li Xiang-Kui
College of Environment Science and Engineering, Guilin University of Technology, Guilin 541004, China.
Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin 541004, China.
Huan Jing Ke Xue. 2021 Apr 8;42(4):1714-1723. doi: 10.13227/j.hjkx.202008068.
In order to clarify the pollution levels of heavy metals in the drinking water sources of the Lijiang River Basin, surface water samples were collected from 62 sites throughout the Lijiang River during May 2019. Heavy metals, including As, Cd, Cr, Mn, Cu, Zn, Hg, Co, and Sb, in the water samples were analysed. Health risk assessments associated with these nine heavy metals were conducted using the health risk assessment model from the US EPA. The results indicated that the order of the average concentrations of heavy metals in the water samples were Mn > Zn > As > Cr > Cu > Sb > Co > Cd > Hg. No heavy metals exceeded the limit values of the drinking water health standards in China (GB 5749-2006), and the concentrations were lower than the limitations of Grade Ⅰ level in the environmental quality standards for surface water (GB 3838-2002). According to the spatial distribution, the high contents areas of As, Cr, Zn, and Sb were predominantly distributed downstream of the Lijiang River, while the high contents areas of Cd, Cu, Hg, Co, and Mn were mostly distributed in the upper reaches. Multivariate analysis indicated that Cd, Mn, Cu, and Co were primarily from agricultural production; Cr, Zn, and Sb were mainly from tourism transportation; As was predominantly from the weathering of rock parent material and soil erosion; Hg was mainly from the improper disposal of domestic garbage and atmospheric deposition. The results of the health risk assessment indicated that children were more susceptible to the threat of heavy metal pollution than adults, and the average annual risk of carcinogenic heavy metals to human health through drinking water ingestion were higher than those of non-carcinogenic metals. The maximum personal average annual health risk of Cr was higher than the maximum allowance levels recommended by the International Commission on Radiological Protection (5×10 a). The average annual risk of non-carcinogenic heavy metals (10-10 a) decreased in the order of Co > Cu > Hg > Zn > Sb > Mn, which were far below the maximum allowance levels recommended by the ICRP.
为了阐明漓江流域饮用水水源地的重金属污染水平，2019年5月从漓江全程62个采样点采集了地表水样本。分析了水样中的砷（As）、镉（Cd）、铬（Cr）、锰（Mn）、铜（Cu）、锌（Zn）、汞（Hg）、钴（Co）和锑（Sb）等重金属。采用美国环境保护局的健康风险评估模型，对这9种重金属进行了健康风险评估。结果表明，水样中重金属平均浓度顺序为：Mn＞Zn＞As＞Cr＞Cu＞Sb＞Co＞Cd＞Hg。没有重金属超过中国饮用水卫生标准（GB 5749-2006）的限值，且浓度低于地表水环境质量标准（GB 3838-2002）中Ⅰ类标准的限值。从空间分布来看，As、Cr、Zn和Sb的高含量区域主要分布在漓江下游，而Cd、Cu、Hg、Co和Mn的高含量区域大多分布在上游。多变量分析表明，Cd、Mn、Cu和Co主要来自农业生产；Cr、Zn和Sb主要来自旅游交通；As主要来自岩石母质风化和土壤侵蚀；Hg主要来自生活垃圾的不当处置和大气沉降。健康风险评估结果表明，儿童比成人更容易受到重金属污染的威胁，通过饮水摄入致癌重金属对人体健康的年均风险高于非致癌金属。Cr的最大个人年均健康风险高于国际放射防护委员会推荐的最大允许水平（5×10⁻⁵ a⁻¹）。非致癌重金属的年均风险（10⁻⁶-10⁻⁵ a⁻¹）顺序为Co＞Cu＞Hg＞Zn＞Sb＞Mn，远低于国际放射防护委员会推荐的最大允许水平。
