EPA Science Inventory

DISTRIBUTION OF CHIRAL PCBS IN SELECTED TISSUES IN THE LABORATORY RAT

Citation:

Lehmler, H. J., I. KaniaKorwel, J. Avants, K. C. Hornbuckle, W. W. Sulkowski, L. W. Robertson, AND A. W. Garrison. DISTRIBUTION OF CHIRAL PCBS IN SELECTED TISSUES IN THE LABORATORY RAT. Presented at 24th International Symposium on Halogenated Environmental Organic Pollutants and POPs, Berlin, Germany, September 6-10, 2004.

Description:

Polychlorinated biphenyls (PCBs) were manufactured for a large number of technical applications including for use in transformers and capacitors. The widespread commercial utilization of PCBs and their persistence in the environment have resulted in their worldwide distribution. Physicochemical characteristics, such as lipophilicity and stability towards biological and thermal degradation, have resulted in their accumulation in the food chain, raising concerns about human health effects. Animal and epidemiological studies have implicated PCBs in a number of human disease processes, such as carcinogenesis and atherosclerosis. However, mechanisms of PCB toxicity are still poorly understood, partly because technical PCB products contain a complex mixture of the possible 209 PCB derivatives or congeners. One of the most intriguing, but frequently overlooked, aspects of PCB toxicity is related to the existence of chiral PCB congeners, possessing at least three ortho (to the biphenyl bridge) chlorine atoms. Racemic PCBs in this group have been implicated in developmental and neurotoxic effects. Two studies with individual congeners have shown that the (+)-enantiomer of PCB 84 and 139 are selectively enriched in tissues, e.g. the liver, of laboratory animals. However, nothing is currently known about the distribution and enrichment of chiral PCBs after administration of a complex PCB mixture to laboratory animals such as the rat. The present study investigates the enantiomeric fraction of PCBs 91, 95 and 149 in male rats after administration of (a) Aroclor 1254 and (b) an environmental mixture obtained from soil contaminated with Chlorofen, a Polish PCB mixture.

Purpose/Objective:

To determine the environmental occurrences, fate, and effects of the enantiomers of selected chiral pesticides and other chiral pollutants.

Record Details:

Record Type: DOCUMENT (PRESENTATION/ABSTRACT)
Start Date: 09/06/2004
Completion Date: 09/06/2004
Record Last Revised: 06/21/2006
Record Created: 07/14/2004
Record Released: 07/14/2004
Record ID: 84725

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL EXPOSURE RESEARCH LAB

ECOSYSTEMS RESEARCH DIVISION

PROCESSES & MODELING BRANCH