Cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg) and arsenic (As) are potent toxicants to human health via dietary intake. It is imperative to establish accurate soil thresholds based on soil-plant transfer models and food safety standards for safe agricultural production. This study takes rice genotypes and soil properties into account to derive soil thresholds for five heavy metal(loid)s using the bioconcentration factors (BCF) and species sensitivity distribution (SSD) based on the food safety standard. The BCF generated from two paddy soils was calculated to investigate the sensitivity of heavy metal accumulation in nine rice cultivars in a greenhouse pot experiment. Then, empirical soil-plant transfer models were developed from a middle-sensitivity rice cultivar (Denong 2000, one selected from nine rice) grown in nineteen paddy soils with various soil properties under a proper exogenously metal(loid)s concentration gradient. After normalization, hazardous concentrations from the fifth percentile (HC5) were calculated from the SSD curves, and the derived soil thresholds were obtained from HC5 prediction models that based on the combination of pH and organic carbon (OC) or cation exchange capacity (CEC). The soil Cd threshold derived based on pH and organic carbon (pH < 7.5, OC ≥ 20 g kg⁻¹) was 1.3-fold of those only considering pH, whereas the Pb threshold (pH > 6, CEC ≥ 20 cmol_c kg⁻¹) was 3.1 times lower than the current threshold. The derived thresholds for five elements were validated to be reliable through literature data and field experiments. The results suggested that deriving soil heavy metal(loid)s threshold using SSD method and local food safety standards is feasible and also applicable to other crops as well as other regions with potential health risks of toxic elements contamination in agricultural production.

镉 (Cd)、铬 (Cr)、铅 (Pb)、汞 (Hg) 和砷 (As) 是通过膳食摄入对人类健康有害的有毒物质。基于土壤-植物转移模型和食品安全标准，建立准确的土壤阈值是农业安全生产的当务之急。本研究将水稻基因型和土壤特性考虑在内，基于食品安全标准，使用生物浓度因子 (BCF) 和物种敏感性分布 (SSD) 推导出五种重金属（类）的土壤阈值。计算了两种水稻土产生的 BCF，以研究温室盆栽试验中 9 个水稻品种对重金属积累的敏感性。然后，从中等敏感性水稻品种中开发了经验土壤-植物转移模型（Denong 2000，一种选自九种水稻）在适当的外源金属（液）浓度梯度下生长在具有各种土壤性质的十九种稻田中。归一化后，根据 SSD 曲线计算来自第五个百分位 (HC5) 的有害浓度，并从基于 pH 值和有机碳 (OC) 或阳离子交换容量 (CEC) 组合的 HC5 预测模型中获得衍生的土壤阈值. 土壤 Cd 阈值基于 pH 值和有机碳（pH < 7.5，OC ≥ 20 g kg 衍生的土壤阈值是从基于 pH 值和有机碳 (OC) 或阳离子交换容量 (CEC) 的组合的 HC5 预测模型中获得的。土壤 Cd 阈值基于 pH 值和有机碳（pH < 7.5，OC ≥ 20 g kg 衍生的土壤阈值是从基于 pH 值和有机碳 (OC) 或阳离子交换容量 (CEC) 的组合的 HC5 预测模型中获得的。土壤 Cd 阈值基于 pH 值和有机碳（pH < 7.5，OC ≥ 20 g kg^-1 ) 是仅考虑 pH 值的 1.3 倍，而 Pb 阈值（pH > 6，CEC ≥ 20 cmol _c kg ^-1）比当前阈值低 3.1 倍。通过文献数据和现场实验验证了五个元素的派生阈值是可靠的。结果表明，利用SSD方法和当地食品安全标准推导土壤重金属（loid）阈值是可行的，也适用于其他作物以及农业生产中存在有毒元素污染潜在健康风险的其他地区。