title: The impact on reproduction of an orally administered mixture of selected PCBs in zebrafish (Danio rerio).
abstract: Zebrafish (Danio rerio) were orally exposed to a mixture of 20 PCBs in three different dose levels (0.008, 0.08, and 0.4 microg of each congener per gram of freeze-dried chironomids). Generally, the PCBs accumulated in a dose-related manner. After 13 weeks of exposure body, liver, and ovary weights, as well as the liver and ovary somatic index, were significantly lower in exposed groups. In addition, the PCB mixture was an effective inducer of hepatic EROD activity. The reproduction study performed with exposed females and unexposed males after 9 weeks revealed that median survival time for larvae was only 7.7 days in the high-dose group as compared with 14 days in controls. Furthermore, egg production was reduced in all three groups exposed. No differences in hatching frequency or median hatching time were recorded. Histologically, females in both the intermediate and high-dose groups contained a reduced number of mature oocytes. The present study demonstrates that the potency of the mixture of selected PCBs induces hepatic EROD activity and has a clearly negative effect on zebrafish reproduction.
authors.affiliation: Faculty of Veterinary Medicine, Department of Pathology, Swedish University of Agricultural Sciences, S-750 07 Uppsala, Sweden.
authors.forename: S
authors.initials: S
authors.lastname: Orn
authors.forename: P L
authors.initials: PL
authors.lastname: Andersson
authors.forename: L
authors.initials: L
authors.lastname: Förlin
authors.forename: M
authors.initials: M
authors.lastname: Tysklind
authors.forename: L
authors.initials: L
authors.lastname: Norrgren
mesh_terms: D000284:Administration, Oral; D000818:Animals; D019363:Cytochrome P-450 CYP1A1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D004334:Drug Administration Schedule; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D008099:Liver / Q000187:drug effects; D008297:Male; D009026:Mortality; D010053:Ovary / Q000187:drug effects; D011078:Polychlorinated Biphenyls / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity*; D012098:Reproduction / Q000187:drug effects*; D014018:Tissue Distribution; D015027:Zebrafish / Q000502:physiology*
chemical_list: D011078:Polychlorinated Biphenyls; D019363:Cytochrome P-450 CYP1A1