Distribution Of Partial Persistent Organic Pollutants (POPs) In Sediments Of The Zhujiang River And Liao River

Polychlorinated dibenzo-dioxins and dibenzofurans （PCDD/Fs）, polychlorinatedbiphenyls （PCBs） and some organochlorine pesticides （OCPs） are the main persistentorganic pollutants （POPs） controlled by the Stockholm Convention. These pollutants havereceived considerable attention in recent decades because of their adverse health effects,persistence, bioaccumulation and ubiquitious presence in the environment. By usingisotope dilution/high resolution gas chromatography （HRGC）-high resolution massspectrum （HRMS） method, the concentrations, PCDD/Fs, PCBs and OCPs from theZhujiang River and Liao River were studied. This thesis is mainly concerned with thefollowing aspects:（1） In this study, the levels of PCDD/Fs and PCBs in sediments from the ZhujiangRiver were investigated. The PCDD/Fs concentrations in sediments ranged from63.7to9364.8pg/g, and the TEQ concentrations of PCDD/Fs ranged from0.14to136.3pgWHO-TEQ/g. As to PCBs, the concentration of the sediments ranged from0.075to1138.6pg/g, the TEQ concentrations ranged from0.00064to54.97pg WHO-TEQ/g. Our researchdemonstrated that the Zhujiang River was heavily polluted by PCDD/Fs and PCBs.（2） Occurrence and distribution of organochlorine pesticides （OCPs） in surfacesediments of the Zhujiang River and Liao River: HCHs, DDTs, HCB, Mirex, Heptachlor,Endrin, Nonachlors, Chlordanes and Heptachlor epoxides were analyzed by isotopedilution/high resolution gas chromatograph-high resolution mass spectrometery（HRGC-MS）. The concentrations of them were0.002-1.98ng·g^-1,0.03-5.07ng·g^-1,0.01-1.54ng·g^-1,0.04-0.68ng·g^-1,0.001-0.15ng·g^-1,0.01-0.68ng·g^-1,0.01-0.58ng·g^-1,0.03-1.40ng·g^-1and0.16-0.95ng·g^-1respectively, and for Liaohe the concentrations of thewere0.09-28.48ng·g^-1,0.08-6.52ng·g^-1,0.18-24.8ng·g^-1,0.02-0.35ng·g^-1,0.006-0.21ng·g^-1,0.004-0.96ng·g^-1,0.004-0.34ng·g^-1,0.02-3.28ng·g^-1and0.01-0.21ng·g^-1respectively. The levels of OCPs in the Zhujiang River had been decreased compared withprevious data. Concentrations of OCPs in Zhujiang River and Liao River were at the samemagnitude compared with those of surface sediments collected from other polluted lakes inChina. The distribution characters of HCHs and DDTs indicated that the OCPs mainlycame from early residues. The risk of OCPs in surface sediments is relatively low when comparing with the ERL and ERM value of risk evaluation.The results indicate that theDDTs may still have potential ecological impact of the investigated area.