College of Resources and Environment, Yunnan Agricultural University, Kunming 650201, China; CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Sci Total Environ. 2023 Jul 10;881:163405. doi: 10.1016/j.scitotenv.2023.163405. Epub 2023 Apr 11.
Soil metal(loid)s in high geological background areas occur mainly in the residual form with low bioavailability, and whether these potentially toxic elements (PTEs) in agricultural soils are harmful to human health is of considerable public concern. A paired survey using both soil and crop samples was conducted using 437 contaminated sites in east Yunnan province, southwest China. The concentration, distribution, and source of PTEs (arsenic (As), copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd), and chromium (Cr)) in agricultural soils, and the contamination levels of and potential health risks from PTEs from different pollution sources were evaluated. Soil Pb, Cu, Zn, Cd, Cr, and As concentrations were higher than the Chinese screening values (GB 15618-2018) of 10.98, 36.16, 24.71, 86.96, 14.19, and 6.64 %, respectively, and Cd greatly exceeded the screening values. Spatial distribution maps indicate that areas with high concentrations of Pb, Cu, Cd, and As were located mainly in mining areas. However, the Zn and Cr concentrations were relatively homogeneous and more dependent on natural processes. The source identification of PTEs shows that Zn and Cr in soils were controlled mainly by the geological background, Pb and As were closely related to anthropogenic activities, and Cu and Cd were related to both sources. Different pollution sources affected crop PTE contents, with average concentrations of Zn, Cd, Cr, and As in high geological background areas significantly lower than in anthropogenic activity areas (p < 0.001), while Cu and As did not differ significantly. Although soil PTEs in high geological background areas represent a relatively high potential risk, they had little impact on crop quality. The hazard indices of different crop products for adults and children followed the sequence: cereals > leafy vegetables > rootstalk vegetables > fruit vegetables. Rootstalk and fruit vegetables are recommended to be grown in the study areas because they are safe for human consumption.
在地质背景较高的地区，土壤金属（类）主要以低生物有效性的残留形式存在，这些农业土壤中潜在的有毒元素（PTEs）是否对人类健康有害，引起了相当大的公众关注。本研究采用土壤和作物样本配对调查的方法，对中国西南云南省东部的 437 个污染场地进行了调查。评估了农业土壤中 PTEs（砷（As）、铜（Cu）、锌（Zn）、铅（Pb）、镉（Cd）和铬（Cr））的浓度、分布和来源，以及不同污染源的 PTEs 污染水平和潜在健康风险。土壤 Pb、Cu、Zn、Cd、Cr 和 As 浓度分别高于中国 10.98、36.16、24.71、86.96、14.19 和 6.64%的筛选值（GB 15618-2018），其中 Cd 大大超过了筛选值。空间分布图表明，高浓度 Pb、Cu、Cd 和 As 主要分布在矿区。然而，Zn 和 Cr 浓度相对均匀，更多地受自然过程控制。PTEs 的来源识别表明，土壤中 Zn 和 Cr 主要受地质背景控制，Pb 和 As 与人为活动密切相关，Cu 和 Cd 与两者都有关。不同的污染源影响作物 PTE 含量，高地质背景区 Zn、Cd、Cr 和 As 的平均浓度明显低于人为活动区（p<0.001），而 Cu 和 As 则没有显著差异。尽管高地质背景地区的土壤 PTEs 具有较高的潜在风险，但对作物质量影响不大。不同作物产品对成人和儿童的危害指数依次为：谷类>叶菜类>根茎类>果菜类。建议在研究区域种植根茎和水果蔬菜，因为它们对人类食用是安全的。
