Role of temperature and enzyme induction in the biotransformation of polychlorinated biphenyls and bioformation of hydroxylated polychlorinated biphenyls by rainbow trout (Oncorhynchus mykiss)
Document Type
Article
Publication Date
6-1-2007
Publication Title
Environmental Science and Technology
Volume
41
Issue
11
First Page
3856
Last Page
3863
Abstract
Hydroxylated PCBs (OH-PCBs) are metabolites of polychlorinated biphenyls (PCBs) that have recently been found in the plasma of Great Lakes fish. Studies have shown that the ability of laboratory-held rainbow trout (Oncorhynchus mykiss) to bioform OH-PCBs from dietary mixtures of PCB congeners is complex and may be attributed to factors such as temperature and/or enzyme induction. Past studies have also suggested that CYP1A- and 2B-like enzymes are the likely mechanism for forming OH-PCBs, but this has not been directly studied in a controlled setting. To address these issues, we exposed rainbow trout (∼80 g) to dietary concentrations of a mixture of three Aroclors (1248, 1254, and 1260), at three water temperatures (8, 12, and 16°C), as well as additional PCBs known to induce CYP1A- and CYP2B-like isoforms in mammals. PCB half-lives in trout were inversely related to water temperature, but biotransformation of PCBs was positively related to water temperature. Thirty-one OH-PCBs were observed in trout plasma after 30 days of dietary exposure to the Aroclor mixtures, although approximately 40% of the ΣOH-PCBs concentrations were OH-PCB for which no standards were available. Concentration of OH-PCBs in the trout plasma increased with increasing temperature and with the addition of CYP2B-like inducing congeners but not with the addition of CYP1A-inducing congeners to food. The results of this study provide the first in vivo evidence that rainbow trout are responsive to CYP2B-like induction by PCBs and that this enzyme system can influence PCB concentrations and OH-PCB formation in fish. © 2007 American Chemical Society.
DOI
10.1021/es062437y
ISSN
0013936X
Recommended Citation
Buckman, Andrea H.; Brown, Scott B.; Small, Jeff; Muir, Derek C.G.; Parrott, Joanne; Solomon, Keith R.; and Fisk, Aaron T.. (2007). Role of temperature and enzyme induction in the biotransformation of polychlorinated biphenyls and bioformation of hydroxylated polychlorinated biphenyls by rainbow trout (Oncorhynchus mykiss). Environmental Science and Technology, 41 (11), 3856-3863.
https://scholar.uwindsor.ca/glierpub/416
PubMed ID
17612160