冶炼厂周边农用地土壤重金属非致癌健康风险评估及修正

为科学量化重金属复合暴露产生的非致癌健康风险，引入靶器官毒性剂量（TTD）模型和证据权重分析模型（WOE）对传统评估模型（HRA）的非致癌健康风险进行修正，并以华中某冶炼厂周边农用地土壤重金属为例，探究3种模型对非致癌健康风险评估结果的影响。结果表明：土壤重金属镉（Cd）、铅（Pb）、铬（Cr）和砷（As）的浓度均值分别为0.37、36.65、69.06和7.66 mg/kg，其中Cd、Pb和Cr不同程度超出研究区土壤背景值，4种重金属传统非致癌健康风险值（HI_HRA）为2.27×10⁻³~3.35×10⁻¹。经TTD模型和WOE模型修正后4种重金属HI_TTD和HI_WOE分别为1.64×10⁻²~5.50×10⁻¹和1.08×10⁻²~6.09×10⁻¹，其中HI_TTD、HI_WOE均值分别为HI_HRA均值的1.88倍和1.17倍。研究显示，对多种重金属复合污染的农用地开展人体非致癌健康风险评估时，需考虑多靶器官效应及重金属间的交互作用，避免传统风险评估方法低估或高估土壤污染对暴露人群产生的实际健康损害。

Assessment and amendment methods of heavy metal non-carcinogenic health risks in agricultural land around smelters

To scientifically quantify the non-carcinogenic health risks of soil combined polluted by heavy metals, the Target Organ Toxicity Dose (TTD) model and Weight of Evidence (WOE) analysis model were introduced to modify the non-carcinogenic health risks assessed by traditional human risk assessment (HRA) model. Adults health risks of heavy metals in agricultural soils surrounding a smelting plant in Central China by using the three methods were compared as a field case. The results showed that the average concentrations of heavy metals cadmium (Cd), lead (Pb), chromium (Cr), and arsenic (As) in the soil were 0.37, 36.65, 69.06, and 7.66 mg/kg, respectively. Among them, Cd, Pb, and Cr exceeded the soil background values to varying degrees. Non-carcinogenic health risk values assessed by HRA (HIHRA) for these four heavy metals ranged from 2.27×10−3 to 3.35×10−1. Amended by TTD and WOE model, HITTD and HIWOE values for the four heavy metals ranged from 1.64×10−2 to 5.50×10−1 and from 1.08×10−2 to 6.09×10−1, respectively. The average values of HITTD and HIWOE were 1.88 and 1.17 times higher than that of HIHRA, respectively. The study emphasized the importance to consider the multi-target organs effect of a specific heavy metals and the interactions among the heavy metals for assessing the non-carcinogenic health risks on agricultural land contaminated with multiple heavy metals. This approach helps to prevent the limitations of traditional risk assessment methods, which may not accurately reflect the real health hazards posed by polluted soil to the population exposed to it.