Metabolism and metabolites of polychlorinated biphenyls

Abstract

The metabolism of polychlorinated biphenyls (PCBs) is complex and has an impact on toxicity, and thereby on the assessment of PCB risks. A large number of reactive and stable metabolites are formed in the processes of biotransformation in biota in general, and in humans in particular. The aim of this document is to provide an overview of PCB metabolism, and to identify the metabolites of concern and their occurrence. Emphasis is given to mammalian metabolism of PCBs and their hydroxyl, methylsulfonyl, and sulfated metabolites, especially those that persist in human blood. Potential intracellular targets and health risks are also discussed.

Keywords:

• hydroxylated PCBs
• polychlorobiphenylols
• PCB methyl sulfones
• PCB sulfates
• human exposure
• reactive intermediates

Acknowledgments

The authors recognize the valuable contributions of Dr. Rachel Marek and Ms Wenxin Koh in producing the data presented in Table 1.

Declaration of interest

This review was in part the work product of the European Food Safety Authority (EFSA) working group on non-dioxin like PCBs 2005. Where the authors’ own work was mentioned, those studies were supported by grants from the NIH (ES07380 and ES013661), DOD, EPA and the EU R&D projects PCBRISK, COMPARE, ANEMONE and RENCO. LWR would also like to recognize the Alexander von Humboldt Foundation for financial support.