Distribution Characteristics And Risk Assessment Of HCHs In Inner Mongolia Irrigation Area Of Yellow River In Tumochuan

The HCHs was identified as the goal pollutant which based on the soil of the Inner Mongolia Irrigation Area of Yellow River in Tumochuan.In this study,the soil samples were collected 30 surface soil samples and 4 soil profile samples,to analyzing the content of HCHs in surface soil samples and in the soil profile samples in Irrigation Area of Yellow River in Tumochuan;to determine how HCHs and its isomers were distributed in surface soil from three aspects of different types of soil,different irrigation conditions and different crops;to discusses the relevance between the physic-chemical properties with the HCHs in the soil profile,and monitor the contaminant source and risk assessment of HCHs in the surface soil.In this paper,the main conclusions are as follows:1.The test results showed that ?-HCH is the main ingredient in four kinds of isomer.The average concentration in order was ?-HCH>?-HCH>?-HCH>?-HCH.The HCHs in the whole irrigation area are existence,but the pollution level is lighter.2.Analyzes the distribution of HCHs and its isomers in surface soil from three aspects of different types of soil,different irrigation conditions and different crops.From the analysis results:the residual of HCHs in different types of soil was medium loam>heavy loam>light loam>clay loam>sand>sand loam;Under the different irrigation conditions,the residual of the HCHs was the Yellow irrigation area>the Hasuhai irrigation area>the wasteland;Under different crops,the residual of HCHs was sunflower>corn>wheat>the wasteland.3.From soil profile samples in irrigated area of Yellow River in Tumochuan,the results show that the HCHs in different samples were detected in different degrees,and the variation of the HCHs is small in different samples in the soil profile.And from the relevance between the physic-chemical properties with the HCHs,the results show that HCHs and salt?conductivity??-HCH??-HCH??-HCH are significant correlation.4.Due to the ratio of ?-HCH/?-HCH was between 0.15-1.59,which indicates that the environmental changes have taken place in the surface soil of Tumochuan irrigation area.In addition,the average value of a-HCH/y-HCH was 0.14,below 2,and a small fraction of the a-HCH/y-HCH ratio in the soil sample is close to 1,which indicates that there is a new y-HCH input in the local area.5.Assessment the health risk and ecological risk of HCHs in the surface soil in irrigated area of Yellow River in tumochuan,the results show that ?-HCH??-HCH??-HCH have no significant effects of the invertebrates in the soil,which indicates the ecological risk of HCHs in surface soil of the Yellow River irrigation area in tumochuan is low;and the carcinogenic risk of HCHs and its isomers in different exposure routes is far lower than 10-6,so it will not cause harm to the health of the exposed population.