Feminization in Common Terns (Sterna hirundo): Relationship to Persistent Organic Contaminants

EPA Grant Number: U914782
Title: Feminization in Common Terns (Sterna hirundo): Relationship to Persistent Organic Contaminants
Investigators: Hart, Constance A.
Institution: Massachusetts Institute of Technology
EPA Project Officer: Klieforth, Barbara I
Project Period: January 1, 1995 through January 1, 1996
Project Amount: $102,000
RFA: STAR Graduate Fellowships (1995) Recipients Lists
Research Category: Academic Fellowships , Endocrine Disruptors , Fellowship - Endocrine Disruptors


The objective of this research project is to investigate the possible link between environmental pollutants and endocrine disruption in an aquatic bird population.

Background: Increasing reproductive and developmental abnormalities in wildlife and human populations and their apparent link to endocrine disrupting contaminants in the environment are of major concern. Although endocrine effects in wildlife have been associated with chemical contaminants, the magnitude and significance of these links are uncertain.


To clarify the links between biological effects and chemical pollutants, field and laboratory studies need to be conducted in combination with mechanistic studies. The health of two common tern populations differing in contaminant exposure will be compared at morphological, histological, and biochemical levels. Observed effects will be correlated with contaminant exposure as measured by both specific chemical contaminants present in yolk sac extracts, and aggregate biological activity of yolk sac extracts as determined by cell culture bioassays. Bioassay endpoints will include cytochrome P450 induction, as well as estrogenic activity. In addition, mechanistic questions will be addressed by examining the ability of yolk sac extracts to bind to estrogen receptors and aryl hydrocarbon receptors that may mediate toxic effects. This research project will provide important information about the links between chemical contamination, biological effects, and mechanisms of toxicity in common terns. Knowledge of such links is crucial for management decisions concerning the impact of environmental contaminants on wildlife and human populations.

Supplemental Keywords:

fellowship, endocrine disruptor, endocrine disrupting contaminants, contaminants, chemical pollutants, aquatic, bioassay, human population, wildlife, aquatic birds, tern, reproductive abnormalities, development abnormalities., RFA, Scientific Discipline, Health, Environmental Chemistry, Health Risk Assessment, Endocrine Disruptors - Environmental Exposure & Risk, endocrine disruptors, Biochemistry, Endocrine Disruptors - Human Health, aquatic ecosystem, assays, aquatic bird population, EDCs, endocrine disrupting chemicals, developmental biology, animal models, birds

Progress and Final Reports:

  • Final