Residues and Distribution Characteristics of Organochlorine Pesticides in Agricultural Soils from Typical Areas of Guangdong Province

Totally 444 samples of surface agricultural soils (0~20 cm depth) were collected in typical regions of Guangdong province from October 2002 to November 2005. The residues and distribution characteristics of 17 kinds of organochlorine pesticides(OCPs)in the collected soil samples were analyzed with gas chromatography. The results showed that OCPs were found in 99.8% of the collected soil samples and ranged from ND to 936.94 ng·g-1. The endosulfan sulfate,methoxychlor,a-endosulfan and p,p′-DDE were the main components,and their contribution to the residues of OCPs was over 50% .The α-HCH,p,p′-DDE,aldrin,b-endosulfan and β-HCH were found over 80% in the collected soil samples. The concentrations of OCPs in the collected soil samples related with different types of land use and descended in the order: vegetable soilbanana soilpaddy soilorchard soils sugarcane soil. The concentrations of OCPs in the samples from Shunde and Shantou were higher than those from remote sites. The concentrations of HCHs in 98.4% of the samples and the concentrations of DDTs in 94.1% of the samples were lower than 50 ng·g-1,which reached the first level of the National Soil Environment Quality Standard (GB 15618-1995). The pollutions of HCHs and DDTs were generally slight in agricultural soils from the typical areas of Guangdong province.