Cytochrome P450 and contaminant concentrations in nestling black-crowned night-herons and their interrelation with sibling embryos

Rattner, B.A.; Melancon, M.J.; Custer, T.W.; Hothem, R.L.

Abstract:

Hepatic cytochrome P450-associated monooxygenase activities were measured in 11-day-old nestling black-crowned night-herons (Nycticorax nycticorax) collected from a reference site (next to Chincoteague National Wildlife Refuge, VA) and three contaminated sites (Cat Island, Green Bay, WI; Bair Island, San Francisco Bay, CA; West Marin Island, San Francisco Bay, CA). Arylhydrocarbon hydroxylase (AHH) and benzyloxyresorufin-O-dealkylase (BROD) activities of nestlings from contaminated sites were only slightly elevated (less than threefold) compared to the reference site. Organochlorine pesticide and total PCB concentrations in nestlings were greatest at contaminated sites, although much lower than found in concurrently collected eggs and pipping embryos. Pollutant concentrations of nestlings were rarely associated with monooxygenase activity. In contrast, concurrently collected pipping heron embryos (often siblings of the nestlings) exhibited pronounced monooxygenase induction (means at contaminated sites elevated up to sevenfold and values of some embryos exceeded 25-fold induction). Furthermore, monooxygenase activity of pipping embryos was significantly correlated with total PCBs, arylhydrocarbon receptor-active PCB congeners and toxic equivalents. The modest monooxygenase responses of heron nestlings suggest that this biomarker may have only limited value during this rapid-growth life stage.

Genre:

Article

ProdID:

5221060

Citation Author:

Rattner, B.A.; Melancon, M.J.; Custer, T.W.; Hothem, R.L.

Citation Contributing Office:

Patuxent Wildlife Research Center

Citation Datum:

Citation Day:

Citation Edition:

Citation Editor:

Citation End Page:

721

Citation Issue:

Citation Keywords:

Citation Language:

English

Citation Larger Work Title:

Environmental Toxicology and Chemistry

Citation LatN:

Citation LatS:

Citation LonE:

Citation LonW:

Citation Month:

Citation No Pagination:

Citation Number Of Pages:

Citation Online Only Flag:

Citation Phsyical Description:

715-721

Citation Projection:

Citation Public Comments:

5006_Rattner.pdf

Citation Publisher:

Citation Series:

Citation Series Code:

Citation Series Number:

Citation Search Results Text:

Cytochrome P450 and contaminant concentrations in nestling black-crowned night-herons and their interrelation with sibling embryos; 1996; Article; Journal; Environmental Toxicology and Chemistry; Rattner, B.A.; Melancon, M.J.; Custer, T.W.; Hothem, R.L.