The Investigation Of The Organochlorine Pesticides In Water Of Beijing

This paper investigates the residual levels of OCPs in water from the industrialand urban sewage and several rivers in Beijing by using solid phase extraction(SPE)and gas-chromatography/electron-capture detection (GC/ECD). This paperanalyzed the residual levels of OCPs in water not only from five kinds of importantcontaminative sewage such as chemical industrial sewage, washing sewage, urbansewage and so on, but also from twelve rivers which concluded Yongdinghe River,Chaobaihe River, Miyun Reservoir and so on. The result indicated that there were α-HCH, β-HCH, γ-HCH, δ-HCH, p,p'-DDTand Endosulfan I which were detected in the industrial and urban sewage water.Their frequency of check-up were respectively 63.2%, 60.5%, 92.1%, 15.8%, 47.4%and 5.26%, the concentration of them were 0.38-69.6ng/L. The order of theirconcentration percentage were: β-HCH (45.1%)> γ-HCH (23.4%)> p,p'-DDT(19.7%) > α-HCH (8.37%) > δ-HCH (1.82%) > Endosulfan I (1.58%). It is obviouslythat the primary residual OCPs were β-HCH, γ-HCH and p,p'-DDT. It was found that the concentration of outflow water were reduced greatly thanthe enter water in the sewage plant. This showed than the sewage plant caneffectively wipe off the OCPs by the metabolism function of animalcule. There were α-HCH, β-HCH, γ-HCH, δ-HCH, p,p'-DDT and Endosulfan Iwhich were also detected in the surface water. Their frequency of check-up wererespectively 75%, 81.2%, 90.6%, 34.4%, 37.5% and 9.38%, the concentration ofthem were 0.31-77.9ng/L. The total concentration of HCHs was 0.54-25.4ng/L andthe average value was 7.41ng/L, which occupied 47.3% of OCPs. The concentrationof the p,p'-DDT was 2.85-77.9ng/L and it's average value was 20.24ng/L whichoccupied 51.6% of OCPs. The content order of isomers of HCH was: β-HCH > γ-HCH > α-HCH > δ-HCH.It was because that β-HCH was very steady and not easy to decomposed and otherisomers would transit into β-HCH. The values of α/γ in surface water were in the range of 0.16-3.51 and most ofthem were less than 1. It indicated that the detected OCPs were most rooted in theremains of what used before and there were no new contamination origin. It could beconcluded that there were new contamination origin of DDT somewhere because ofthere were no DDE and DDD but only matrix compound of DDT were detected insurface water.