Dudka S, Piotrowska M, Terelak H
The University of Georgia Department of Crop and Soil Sciences, 3111 Miller Plant Science Building, Athens, GA 30602, USA.
Environ Pollut. 1996;94(2):181-8. doi: 10.1016/s0269-7491(96)00069-3.
The documeneed adverse health effects of soil Cd and Pb have led to public concern over soil contamination with metals. A 4-year field experiment was conducted to study the transfer of Cd, Pb, and Zn from soil contaminated by smelter flue-dust to crop plants grown in a rotation. The soil was amended with Pb?Zn smelter flue-dust (2-66.8 kg per 10 m(2) plot) to simulate the long-term effect that the smelting of non-ferrous metal ore has on arable soils. The treated soil became strongly contaminated with metals (Cd 3.2-106 mg/kg, Pb 146-3452 mg/kg, Zn 465-11 375 mg/kg). Concentrations of Cd, Pb, and Zn in barley grain, barley straw meadow bluegrass, red clover, and potatoes were generally low. The highest metal concentrations were found in potato tubers (intact), meadow bluegrass, and barley straw. The observed reduction in crop yield was probably the result of possible nutrient imbalances rather than of metal (Zn, Cu) phytotoxicities. Zn and Cd uptake by the plants can be described by the saturation (plateau) model (y = ax(b), b < 1). The relationship between Pb in the soil and plants was linear with an extremely low slope (0.0001-0.0003). No excessive dietary intake of Cd is expected when Cd concentrations in barley grain and potato tubers grown on the contaminated soil are not higher than 0.6 and 1.0 mg/kg, respectively. Based on the risk analysis and taking into account the saturation model of the soil-plant metal relationship, it was concluded that, under the conditions of this experiment (neutral soil pH), soil with Cd concentrations of up to 30 mg/kg is still safe for production of these crop plants.
土壤中镉和铅对健康产生的不良影响引发了公众对金属污染土壤的关注。开展了一项为期4年的田间试验，研究镉、铅和锌从受冶炼厂烟尘污染的土壤向轮作种植的作物的转移情况。用铅锌冶炼厂烟尘（每10平方米地块2 - 66.8千克）改良土壤，以模拟有色金属矿石冶炼对耕地土壤的长期影响。处理后的土壤受到严重金属污染（镉3.2 - 106毫克/千克，铅146 - 3452毫克/千克，锌465 - 11375毫克/千克）。大麦籽粒、大麦秸秆、草地早熟禾、红三叶草和马铃薯中的镉、铅和锌浓度总体较低。金属浓度最高的是马铃薯块茎（完整的）、草地早熟禾和大麦秸秆。观察到的作物产量下降可能是营养失衡而非金属（锌、铜）的植物毒性所致。植物对锌和镉的吸收可用饱和（平台）模型（y = ax(b)，b < 1）来描述。土壤中铅与植物之间的关系呈线性，斜率极低（0.0001 - 0.0003）。当在受污染土壤上种植的大麦籽粒和马铃薯块茎中的镉浓度分别不高于0.6毫克/千克和1.0毫克/千克时，预计不会出现镉的过量膳食摄入。基于风险分析并考虑到土壤 - 植物金属关系的饱和模型，得出结论：在本试验条件下（土壤pH值为中性），镉浓度高达30毫克/千克的土壤对这些作物的生产仍是安全的。
