PCDD F-S, PCBS, HCHS AND HCB IN SEDIMENTS AND SOILS OF YA-ER LAKE AREA IN CHINA - RESULTS ON RESIDUAL LEVELS AND CORRELATION TO THE ORGANICCARBON AND PARTICLE SIZE/

Sediments and soils collected from the Ya-Er Lake area in China were a nalysed for the polychlorinated dibenzo-p-dioxins and dibenzofurans (P CDD/Fs), polychlorinated biphenyl (PCBs), hexachlorocyclohexane (HCHs) and hexachlorobenzene (HCB). The results indicated the main pollution problems in the Ya-Er Lake area, which was heavily polluted by HCHs a nd chlorobenzenes, now is dominantly polluted by PCDD/Fs, PCBs and HCB . The occurrence of PCDD/Fs and PCBs with relatively high levels of Hp CDDs, OCDD and low chlorinated-substituted PCBs, is attributed to the discharge of waste water and biodegradation. The vertical distribution s of HCH-residues are related with the content of organic carbon and p article size. Copyright (C) 1996 Elsevier Science Ltd