John Wiley & Sons, Ltd.

Toxicokinetics of polybrominated diphenyl ethers across life stages in the northern leopard frog, Lithobates pipiens

0
Polybrominated diphenyl ethers (PBDEs), a class of flame retardants, are bioaccumulative toxins which can biomagnify in food webs. However, little is known about toxicokinetics of total and congener‐specific BDEs in lower vertebrates. We exposed northern leopard frog [Lithobates (Rana) pipiens] tadpoles to diets containing DE‐71 (a pentabromodiphenyl ether mixture; [0 (control), 71.4, and 634 DE‐71 ng/g wet mass]) for 50 days, followed by a period of depuration during which they were fed only undosed (control) food. After 28 days, tadpoles eliminated over 94% of the ΣPBDEs from their tissues (t½= 5.9 ± 1.9 d) with no significant differences in elimination rates for the predominant congeners. Elimination of BDE‐99 was independent of dose, indicating first order kinetics, and it did not fit a biexponential model significantly better than a monoexponential model, indicating single compartment elimination. To compare developmental life‐stage kinetics following larval exposure, we collected individuals at the beginning and end of metamorphosis, and at 70 days post‐metamorphosis. During metamorphosis, total body residues per individual did not significantly change, implying little to no elimination. After 70 days, juvenile frogs eliminated 89.7% of the ΣPBDEs from their tissues, and BDE‐47 was eliminated at a faster rate (t½= 17.3 d) than BDE‐99 and BDE‐100 (t½= 63.0 and 69.3 d, respectively). Because kinetics of PBDEs in L. pipiens differed among life‐stages, developmental life‐stage—especially for species that undergo metamorphosis—should be should be considered when determining toxicity of persistent organic pollutants. Environ. Toxicol. Chem. © 2013 SETAC

Customer comments

No comments were found for Toxicokinetics of polybrominated diphenyl ethers across life stages in the northern leopard frog, Lithobates pipiens. Be the first to comment!