title: Contaminants in eggs of colonial waterbirds and hepatic cytochrome P450 enzyme levels in pipped tern embryos, Washington State.
abstract: Eggs of Forster's terns (Sterna forsteri) collected in 1991 from nesting colonies on Crescent Island (Columbia River) and the Potholes Reservoir in south central Washington generally contained low residues of organochlorine pesticides and metabolites, 2,3,7, 8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, and polychlorinated biphenyls (PCBs). Hepatic cytochrome P450 enzyme activity in pipped embryos of Forster's terns from the two colonies seemed unaffected by contaminants. At Crescent Island, examination of 23 Forster's tern eggs with large embryos (19 viable [10 pipped] and four dead [two pipped]) revealed developmental abnormalities in two viable pipped embryos (missing maxilla and deformed pelvic girdle) and a viable prepipping embryo (shortened beak). Our limited sample sizes and number of compounds analyzed preclude us from determining whether or not the abnormalities are related to contaminants. No abnormalities were noted in 10 pipped eggs (nine viable and one dead at collection) of Forster's terns collected from the Potholes Reservoir colony. Eggs of Caspian terns (Sterna caspia) collected from Crescent Island in 1991 also contained generally low residues of contaminants, only one developmental abnormality was noted, and limited data indicated that cytochrome P450 enzyme activity apparently was unaffected by contaminants. Organochlorine contaminants were generally low in addled eggs of American white pelicans (Pelecanus erythrorhynchos) collected from Crescent Island in 1994.
authors.affiliation: USGS, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, Oregon 97331, USA.
authors.forename: L J
authors.initials: LJ
authors.lastname: Blus
authors.forename: M J
authors.initials: MJ
authors.lastname: Melancon
authors.forename: D J
authors.initials: DJ
authors.lastname: Hoffman
authors.forename: C J
authors.initials: CJ
authors.lastname: Henny
mesh_terms: D000818:Animals; D001717:Birds / Q000196:embryology / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004531:Eggs / Q000032:analysis*; D004625:Embryo, Nonmammalian / Q000002:abnormalities / Q000378:metabolism; D008099:Liver / Q000196:embryology / Q000201:enzymology*; D010573:Pesticide Residues / Q000032:analysis*; D014861:Washington
chemical_list: D010573:Pesticide Residues; D003577:Cytochrome P-450 Enzyme System