Distribution And Risk Assessment Of HCHs In Ma Di Hao Irrigation Area Of Inner Mongolia

HCHs is a kind of typical persistent organic pollutants, the migration enrichment of HCHs in plant body, its biological chemicals that make HCHs ends up with the food chain enter human body, to have certain threat to food safety and human health. The HCHs was identified as the goal pollutant which based on the soil of Ma di hao irrigation area of Inner Mongolia as the study area, analysis the HCHs level of residues in the soil and pollution status, analyzes the distribution of HCHs from the type of soil, irrigation, crop structure, analyzes the relationship with the physical and chemical properties, source analysis and risk assessment for it. Main conclusions are as follows:(1) Detection rate of HCHs in Ma di hao irrigation soil is higher, the a-HCH and y-HCH is 100%; (3-HCH is 74.19%; 8-HCH is 96.77%., HCHs content in the range of 1.333 ng.g-1～21.128 ng. g-1, the average level of 8.995 ng. g-1, the pesticide residue of HCHs in Ma di hao irrigation area is in lower average level.(2) Analyzes the distribution of HCHs and its isomer from the type of soil, irrigation, crop structure. From the analysis results of HCHs in different soil residual was light loam> sand> heavy loam> sand loam> clay loam; From the analysis results of HCHs under different irrigation conditions was Well water irrigation area> The Yellow River irrigation area> dry land> Heihe river irrigation area; Different crops of HCHs residues in soil for wasteland>corn>Chinese wolfberry poplar>alfalfa>sunflower> Philippine. Respectively tested the properties of soil organic matter, pH, salt and moisture content, from the analysis results, pH and HCHs significantly related.(3) Evaluating ecological and health risks of the irrigation area. From the point of ecological risk, Ma di hao in irrigation farmland soil on the surface of HCHs pesticide without risk; From the perspective of health risk assessment, breath way cancer risk exposure is far less than through the mouth exposed way far and skin cancer risk exposure pathways cancer risk, the comprehensive risk except 2,15,20,24 of sample point than risk limit, exceeding the maximum limit risk measures should be taken to strengthen prevention.