Funding Program: Contaminant Biology

Statement of Problem: The brominated compound, polybrominated diphenylether (PBDE) is commonly used as a flame retardant in textiles, plastics, electronics, and construction materials. These chemicals have been found to be environmentally persistent and quite mobile in their distribution. PBDE has become a diffuse, ubiquitous pollutant that is increasing dramatically throughout the world (Peterman in review; Lindberg 2004; Verrault 2005), and has been even detected in Alaskan polar bears (Muir et al. 2006; Kannan et al. 2005). The biological hazards posed by these chemicals include thyroid function, neurological development and behavioral performance. In North America PBDE levels in aquatic biota are projected to double every 5 years. PBDEs are transported through air and water as well as through the food chain, thus there are multiple pathways for amphibian exposure. The causes for the world-wide decline of amphibians have not been clearly identified but could likely include climate, pathogens, parasites, and toxic substances. A persistent pollutant of such widespread distribution as PBDE is of concern because of its increasing environmental concentration and potential toxicity. In spite of these concerns with PBDE pollution, little information exists on the toxicity of this pollutant, especially to aquatic organisms such as amphibians. Amphibians can serve as model organisms to understand the environmental impact of PBDEs. Adverse impacts on these organisms are expected because PBDE interferes with thyroid function (deWit, 2002; Darnerud, 2003), which is critical for development and metamorphic changes. Any negative change in these endpoints can have population-wide impacts. For instance, in frogs, increases in the length of the larval period and decreases in the mass at metamorphosis have been linked to declines in adult fitness (Semlitsch et al., 1988).
 
Objectives: Determine the effects of environmentally realistic concentrations of PBDEs on developing wood frog tadpoles, gaining a better understanding of PBDE distribution in the Kenai Peninsula in Alaska.