Studies on organochlorine environmental contaminants with emphasis on analytical methods and occurrence in humans

Abstract: Methods for multicomponent analysis of lipophilic organochlorine contaminants(OCs) in blood plasma and lipid-rich tissues are presented. By using the describedmethods, polychlorinated biphenyls (PCB), polychlorinated naphthalenes (PCN), hexachlorobenzene(HCB), 1,1-dichloro-2,2-bis(4 chlorophenyl)ethene (p,p'-DDE) and methylsulphonylmetabolites of PCB (MeSO2-PCB) and p,p'-DDE (Meso2-DDE) were determined in humanblood plasma, adipose tissue and liver. In addition, polychlorinated dibenzo-p-dioxinsand dibenzofurans (PCDD/F) were determined in selected samples of blood plasma. The profiles and levels of PCB, PCN, HCB andp,p'-DDE were similar in adipose tissueand liver, while differences were found for MeSO2-PCB and MeSO2-DDE. The concentration(on lipid weight basis) of the metabolites was about 10 times higher in liver thanin adipose tissue. Furthermore, meta-substituted isomers of MeSO2-PCB were selectivelyretained in the liver. The most abundant methylsulphonyl metabolite in the liverwas 3-MeSO2-2,2',3',4',5,6-hexaCB, followed by 3-MeSO2-DDE. In adipose tissue, 3-MeSO2-DDEwas the most abundant metabolite. PCB, HCB, p,p'-DDE, MeSO2-PCB and MeSO2-DDE were determined in whole plasma andin the fractions obtained afler separation of the plasma into very low density lipoprotein(VLDL), low density lipoprotein (LDL), high density lipoprotein (HDL) and lipoproteindepleted (LPDP) fractions. The OCs were present in all fractions, but predominantlyin the LPDP fraction. A tendency to greater association of meta-substituted compoundsof MeSO2-PCB to the LPDP fraction was noted. Among the lipoprotein fractions, LDLwas the main carrier of PCB, HCB and p,p'-DDE. 3-MeSO2-DDE was predominantly foundin the HDL fraction and MeSO2-PCB was distributed about equally between LDL and HDLfractions. A local source of contamination with PCB and PCN was traced to old electronicequipment, which was temporarily stored next to the laboratory. It was shown thatPCB and PCN may emit from electronics and pollute the indoor air. However, occupationalexposure to PCB, PCN, PCDD/F and/or HCB could not be confirmed in a pilot study ofplasma from persons who had worked with cable incineration or electronic equipment. ISBN 91-628-2659-X