title: Health of tree swallow (Tachycineta bicolor) nestlings exposed to chlorinated hydrocarbons in the St Lawrence River basin. Part I. Renal and hepatic vitamin A concentrations.
abstract: Sixteen-day-old tree swallows (Tachycineta bicolor), near fledging, were collected in 1999 and 2000 from nine sites representing a gradient of dioxin concentrations, within the vicinity of the St. Lawrence River in Canada and the United States, to determine if organochlorine contaminants correlated with vitamin A levels measured as retinol and retinyl palmitate. Mean concentrations of hepatic retinol ranged from 3 mg /kg to 13 mg /kg, and from 0.35 mg /kg to 1.5 mg /kg for renal retinol. Mean concentrations of hepatic retinyl palmitate ranged from 18 mg /kg to 146 mg /kg, and 1mg /kg to 6 mg/kg for renal retinyl palmitate. In 1999, molar ratio of renal retinol: retinyl palmitate was significantly and positively correlated with total polychlorinated dibenzodioxin (PCDD) concentration. Among sites, total PCDDs ranged from 5.4 ng /kg wet weight to 79.5 ng /kg wet weight in tree swallows. These results suggest that current levels of organochlorine contaminants in the St. Lawrence River and surrounding tributaries may be interacting with the vitamin A pathway. Lower circulating levels and higher tissue concentrations of retinoids may result in compromised immune function and reduced reproductive success in adult birds.
authors.affiliation: Department of Biology, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Barbara
authors.initials: B
authors.lastname: Martinovic
authors.forename: D R S
authors.initials: DR
authors.lastname: Lean
authors.forename: Christine A
authors.initials: CA
authors.lastname: Bishop
authors.forename: Erinn
authors.initials: E
authors.lastname: Birmingham
authors.forename: Anne
authors.initials: A
authors.lastname: Secord
authors.forename: Ken
authors.initials: K
authors.lastname: Jock
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001717:Birds / Q000378:metabolism*; D002170:Canada; D004781:Environmental Exposure; D004785:Environmental Pollutants / Q000633:toxicity*; D005618:Fresh Water; D006843:Hydrocarbons, Chlorinated / Q000633:toxicity*; D007313:Insecta / Q000378:metabolism; D007668:Kidney / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D013997:Time Factors; D014481:United States; D014801:Vitamin A / Q000378:metabolism*
chemical_list: D004785:Environmental Pollutants; D006843:Hydrocarbons, Chlorinated; D014801:Vitamin A