Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Zhejiang University, Hangzhou, 310058, China.
Key Laboratory of Environmental Remediation and Ecosystem Health, Ministry of Education, Zhejiang University, Hangzhou, 310058, China.
Environ Sci Pollut Res Int. 2019 Dec;26(36):36558-36567. doi: 10.1007/s11356-019-06716-4. Epub 2019 Nov 15.
Food chain contamination by soil cadmium (Cd) through vegetable consumption poses a threat to human health. It is imperative to understand the Cd uptake and transfer in different soil-vegetable systems. The aims of this study were to understand the effect of soil characteristics on Cd accumulation and transfer in pepper and to derive regression models to predict Cd concentrations in the vegetable grown on a wide range of soils with different properties. The accumulation and transfer of Cd in the root, stem, and fruit of pepper (Capsicum annuum L.) grown in 18 typical soils of China were investigated through pot experiments. The bioavailability of Cd in soil was evaluated by using EDTA and HNO extraction methods. The pot experiments included a control and two concentration levels of Cd salt added to soils according to Soil Environmental Quality Standards of China. The results showed that the Cd content in pepper fruits ranged from 0.007 to 0.049 for the control, 0.045 to 0.260 for the low Cd treatment, and 0.076 to 0.345 mg/kg for the high Cd treatment, respectively. The concentrations of Cd in the different parts of pepper decreased in the order of root > stem > fruit, and there were significant correlations among the Cd concentrations in pepper root, stem, and fruit tissues. Bioaccumulation factor (BCF) and transfer factor (TF) of Cd in pepper fruits exhibited a low accumulation of Cd in the fruit of pepper. The Cd accumulation in pepper fruit could be quantitatively predicted by EDTA-extractable Cd content in soils. Multiple linear regression models proved functional in predicting Cd accumulation in different parts of pepper. The Cd content in pepper tissues was well predicted using EDTA-extractable Cd and soil variables, such as pH, EC, CEC, total phosphorus, and CaCO content. Soil pH and EC were major soil factors influencing Cd transfer from soil to pepper fruits, whereas total phosphorus content presented a negative effect on Cd accumulation in stem and root parts of pepper.
通过食用蔬菜，食物链中土壤镉（Cd）的污染对人类健康构成了威胁。了解不同土壤-蔬菜系统中 Cd 的吸收和转移至关重要。本研究旨在了解土壤特性对辣椒中 Cd 积累和转移的影响，并建立回归模型，以预测在具有不同性质的广泛土壤上种植的蔬菜中 Cd 的浓度。通过盆栽实验研究了 18 种中国典型土壤中生长的辣椒（Capsicum annuum L.）根、茎和果实中 Cd 的积累和转移。采用 EDTA 和 HNO3 提取方法评价土壤中 Cd 的生物有效性。盆栽实验包括对照和根据《土壤环境质量标准》向土壤中添加两种浓度水平的 Cd 盐。结果表明，对照处理下，辣椒果实中 Cd 含量为 0.0070.049mg/kg，低 Cd 处理下为 0.0450.260mg/kg，高 Cd 处理下为 0.076~0.345mg/kg。辣椒不同部位 Cd 浓度顺序为根＞茎＞果，且辣椒根、茎、果实组织中 Cd 浓度之间存在显著相关性。辣椒果实中 Cd 的生物积累因子（BCF）和转移因子（TF）均表现出对 Cd 的低积累。EDTA 可提取土壤 Cd 含量可定量预测辣椒果实中 Cd 的积累。多元线性回归模型可有效预测不同部位辣椒中 Cd 的积累。利用 EDTA 可提取 Cd 和土壤变量（如 pH、EC、CEC、总磷和 CaCO3 含量），可较好地预测辣椒组织中的 Cd 含量。土壤 pH 和 EC 是影响 Cd 从土壤向辣椒果实转移的主要土壤因素，而总磷含量对辣椒根和茎部分中 Cd 的积累则呈现负效应。
