Oral exposure of PBDE-47 in fish: toxicokinetics and reproductive effects in Japanese Medaka (Oryzias latipes) and fathead minnows (Pimephales promelas).
The toxicokinetics of 2,2,4,4-tetrabromodiphenyl ether (PBDE-47) was studied in the Japanese Medaka (Oryzias latipes) after a single oral exposure followed by termination at specific time points. The effects of repeated oral exposure to PBDE-47 on reproductive performance was assessed using a pair breeding experimental design with fathead minnows (Pimephales promelas) given daily PBDE-47 exposures for 25 days, during which fecundity was measured as an indicator of reproductive performance. Medaka and fathead minnows were orally exposed to PBDE-47 by bioencapsulation in brine shrimp, Artemia sp. In the medaka studies, measurable levels of PBDE-47 were detected in the carcass within 0.25 h with peak levels occurring at 8 h. The body levels of PBDE-47 slowly declined and were still 25% of peak levels at 624 h after dosing. Assimilation of the bioencapsulated dose was at least 80% and may well approach 100%. The PBDE-47 concentration-time profile was fitted to a one-compartment clearance-volume toxicokinetic model and the model-predicted value for elimination half-life was determined to be 281 h and the first-order absorption rate constant was Ka = 0.26 hr(-1). In the fathead minnow study, egg laying in the PBDE-treated breeding pairs stopped after 10 days. The condition factor of PBDE-treated males was significantly reduced (P <0.011) compared with control males, whereas no significant difference was observed in females. Histological examination revealed a greater than 50% reduction in mature sperm in PBDE-47 exposed minnows compared to controls. Collectively, these results suggest PBDE-47 is selectively toxic to sexually mature male fathead minnows.
Muirhead
Elisabeth K
EK
Marine Sciences Laboratory, Battelle, Pacific Northwest National Laboratory, Sequim, Washington 98382, USA.
Skillman
Ann D
AD
Hook
Sharon E
SE
Schultz
Irvin R
IR
D000284:Administration, Oral; D000818:Animals; D003530:Cyprinidae; D005260:Female; D055768:Halogenated Diphenyl Ethers; D006842:Hydrocarbons, Brominated / Q000493:pharmacokinetics* / Q000633:toxicity*; D008297:Male; D009990:Oryzias; D010647:Phenyl Ethers / Q000493:pharmacokinetics* / Q000633:toxicity*; D012098:Reproduction / Q000187:drug effects*
D055768:Halogenated Diphenyl Ethers; D006842:Hydrocarbons, Brominated; D010647:Phenyl Ethers; C511295:2,2',4,4'-tetrabromodiphenyl ether