168th National Meeting of the American Association for the Advancement of Science. Boston, MA. February 14-19, 2002.

Environmental estrogens and women's health symposium.

Identification and assessment of endocrine disrupting chemicals.

Fertuck KC.

Department of Biochemistry & Molecular Biology, National Food Safety & Toxicology Center, and Institute for Environmental Toxicology, Michigan State University, East Lansing, MI.

Estrogen plays a variety of vital roles in reproduction and development in both females and males. As a result, the discovery that many dietary and pollutant compounds are able to interact with the estrogen receptor has raised many important issues. Among these are questions concerning the actual risk posed by current intake levels of these chemicals, as well as the most effective ways to screen other compounds for potential agonist (estrogen-mimicking) or antagonist (estrogen-opposing) activity. Recent legislation outlining federally-mandated testing requirements will be discussed. As well, use of a complementary series of in vitro and in vivo tests will be described, using recent work with polycyclic aromatic hydrocarbons as an example. These in vitro tests are able to assess the ability of a compound of interest to compete with estrogen for binding to the or isoform of the estrogen receptor and to induce or inhibit estrogen receptor-mediated gene expression. Chemicals of concern, based on these initial screening tests, are then further evaluated in in vivo tests, where their ability to cause increased uterine weight and modify expression of key estrogen-regulated genes is evaluated. Strengths and weaknesses of these tests will be discussed.