Effects of pond water, sediment and sediment extract samples from New Hampshire, USA on early Xenopus development and metamorphosis: Comparison to native species

In an effort to assess potential ecological hazards to amphibian species in selected regions within New Nampshire, the traditional Frog Embryo Teratog enesis Assay-Xenopus (FETAX), a 14-/21 day tail resorption thyroid disrupti on assay and > 30 day limb development tests were conducted with representa tive surface water and sediment samples. Two separate sets of samples colle cted from five sites were evaluated. The primary objectives of the study we re to determine if samples were capable of inducing early embryo-larval mal development, to determine if maldevelopment included limb defects, to deter mine if thyroxine co-administration altered the rates of limb malformation and to evaluate the impact of the samples on growth rates, developmental pr ogress and metamorphic climax. Results from these studies suggested that po nd water and sediment extract samples, but not whole sediment samples, from B2, FW, LP and W ponds were capable of inducing abnormal early embryo-larv al development. In addition, water samples from B2 and W ponds induced sign ificant abnormal hindlimb development. Some abnormal forelimb development w as noted in the tail resorption studies, but not to the same extent as the hindlimbs, Each of the water samples induced appreciable developmental dela y, including the paired reference site B1, which could be reversed by the a ddition of exogenous thyroxine, Copyright (C) 2001 John Wiley & Sons, Ltd.