Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Science, Ministry of Ecology and Environment, Nanjing 210042, China.
College of Environment Science and Engineering, Yangzhou University, Yangzhou 225127, China.
Int J Environ Res Public Health. 2022 Jul 21;19(14):8854. doi: 10.3390/ijerph19148854.
Widespread soil contamination is hazardous to agricultural products, posing harmful effects on human health through the food chain. In China, Cadmium (Cd) is the primary contaminant in soils and easily accumulates in rice, the main food for the Chinese population. Therefore, it is essential to derive soil criteria to safeguard rice products by assessing Cd intake risk through the soil-grain-human pathway. Based on a 2-year field investigation, a total of 328 soil-rice grain paired samples were collected in China, covering a wide variation in soil Cd concentrations and physicochemical properties. Two probabilistic methods used to derive soil criteria are soil-plant transfer models (SPT), with predictive intervals, and species sensitivity distribution (SSD), composed of soil type-specific bioconcentration factor (BCF, Cd concentration ratio in rice grain to soil). The soil criteria were back-calculated from the Chinese food quality standard. The results suggested that field data with a proper Cd concentration gradient could increase the model accuracy in the soil-plant transfer system. The derived soil criteria based on soil pH were 0.06-0.11, 0.33-0.59, and 1.51-2.82 mg kg for protecting 95%, 50% and 5% of the rice safety, respectively. The soil criteria with soil pH further validated the soil as being safe for rice grains.
土壤广泛污染对农产品构成危害，通过食物链对人类健康产生有害影响。在中国，镉（Cd）是土壤中的主要污染物，容易在大米中积累，大米是中国人的主要食物。因此，通过评估土壤-谷物-人类途径中的镉摄入风险，获得土壤标准来保护稻米产品是至关重要的。基于两年的田间调查，在中国共采集了 328 个土壤-稻谷配对样本，涵盖了土壤镉浓度和理化性质的广泛变化。两种概率方法用于推导土壤标准，即土壤-植物转移模型（SPT），具有预测区间，和物种敏感性分布（SSD），由特定土壤类型的生物浓缩因子（BCF，稻谷中镉浓度与土壤的比值）组成。土壤标准是从中国食品质量标准中反推出来的。结果表明，具有适当镉浓度梯度的田间数据可以提高土壤-植物转移系统中模型的准确性。基于土壤 pH 值推导的土壤标准分别为 0.06-0.11、0.33-0.59 和 1.51-2.82mg/kg，以分别保护 95%、50%和 5%的稻米安全。具有土壤 pH 值的土壤标准进一步验证了土壤对稻谷的安全性。
