Sublethal Effects of Endocrine Disrupting ContaminantsEPA Grant Number: U916162
Title: Sublethal Effects of Endocrine Disrupting Contaminants
Investigators: LaFiandra, Emily M.
Institution: University of New Hampshire - Main Campus
EPA Project Officer: Cobbs-Green, Gladys M.
Project Period: January 1, 2003 through January 1, 2006
Project Amount: $125,566
RFA: STAR Graduate Fellowships (2003) Recipients Lists
Research Category: Fellowship - Toxicology , Academic Fellowships , Health Effects
The prevalence of malformed amphibians and the association of high incidences of malformation with the presence of environmental contaminants have raised questions about the effects of contaminants such as polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloro-ethane (DDT), and numerous pesticides on the development of larval amphibians. Pesticides have been documented to have endocrine disrupting effects, suggesting that many of the observed reproductive and developmental abnormalities may be because of the alteration of steroidogenesis. The objectives of this research project are to: (1) investigate partly the effects of exposure to environmental contaminants such as DDT and Atrazine on the survival, growth, development, gonadal histology, and steroidogenesis of larval anurans; and (2) demonstrate connections between abnormal development and malfunctioning of the endocrine system.
Coordinated field sampling, in situ exposures, and laboratory toxicology experiments will be used in a weight of evidence approach. Field surveys will be conducted at National Wildlife Refuges (NWRs) in New Hampshire, Maine, Vermont, and New York as part of an ongoing study documenting amphibian malformation rates on refuges. In situ exposures will be conducted at Great Bay NWR, Newington, NH, as sites on this refuge have high incidences of malformations as well as contamination with PCBs, DDT, and/or Atrazine. Enclosures will be installed at sites known to be contaminated with DDT as well as at relatively uncontaminated or reference sites. The in situ work will allow for repeated monitoring of the development of a genetically similar group of test organisms under relatively natural, yet predator-free conditions. This work also will allow for direct comparisons among reference and contaminated sites and may provide additional evidence suggesting that contaminants present in these sites contribute to amphibian malformations. The role these contaminants play in abnormal amphibian development will be further investigated in laboratory toxicology experiments using sediments spiked with DDT at concentrations similar to those found in sediments at Great Bay NWR. This coordination of field, in situ, and laboratory experiments is intended to demonstrate a connection between amphibian malformations observed in the field and endocrine disruption by pesticides present in the environment.