The Toxicological Effects Of Antimony On Different Plants And Its Soil Ecological Criteria

Antimony (Sb) is a toxic carcinogenic elements, destruction of plant cell metabolism and other activities. In the soil is absorbed by plants, accumulated in the root, stem, and then enter the food chain and endanger human health. Currently, there are relatively few ecological toxicological data of antimony in soil, and the lack of the method of experimental design and standardized toxicity test, the sensitivity of the selected species is different, the soil quality is different, really a serious shortage of data can be used to derive the value of the ecological benchmarks, the soil ecological toxicity effect data is relatively sporadic, scattered and lack of systematic consolidation. Lead to the development of the environmental quality standards of antimony in the soil is seriously lagging behind, is not conducive to soil environmental management of the country. Therefore, according to the dose effect relationship based on the ecotoxicological experiment, to establish the toxicity threshold of pollutants based on different evaluation end points, for different environmental objectives, different soil and receptors, consider regional differences, adjusting the corresponding parameters and evaluating factors to adapt to the local environmental conditions and characteristics, and ultimately used to derive the reference value of soil ecology.In this study, antimony potassium tartrate to target pollutants, selected sand, soil, red soil and black soil four different types of soil, each soil sample was added to a range of concentrations of antimony potassium tartrate solution. Various soil samples were subjected to aging, grinding and sieving. According to the related steps and principles of China’s chemical testing methods and ISO standardization process, the seed germination (pre-test and formal test), root elongation test and early growth toxicity were explored, study the effect of antimony on the ecological toxicity of plants, and the toxicity threshold (EC10) for the inhibition of the growth of plant root elongation and plant height was obtained; also discussed the influence of soil properties on toxicity thresholds, and the model of predicting the toxicity threshold of antimony in different soil properties was constructed, the ecological reference value of antimony was deduced. The test results show that:with antimony concentration increased, the seed germination rate and root length of barley, wheat, cucumber were increased firstly, and then decline, the low concentration of antimony shown the effect of stimulating growth, cucumber that is most significant inhibition; root length and plant height of barley, oats and rape were obtained by the inhibition of root elongation test, under the action of a series of concentrations of exogenous antimony, the root length and plant height showed similar toxic effects, the general is decreasing, the value of EC10 was slightly different, the inhibition rate and the significant difference in different soil. Through early growth toxicity test of wheat show that, the plant biomass was also decreased with the increase of the concentration of antimony. At low concentrations, the biomass increased, the dry weight and fresh weight of the plant were sensitive to the toxicity of antimony, and the inhibition rate is high, more suitable for evaluation index. PH, OC and CEC in soil impact on the toxicity threshold of antimony greater, and the 3 factor prediction model based on PH, OC and CEC could be used to predict the toxicity threshold of antimony in different soil types, but it still needs to be verified by the test data of different types of soil and different plants. Through this study and relevant data from the literature, construct species sensitivity distribution curve derived HC5 value, obtained antimony soil ecological reference value is 23.2mg/Kg, which provides reference data for the formulating of soil ecological benchmark value of antimony in China.