Do environmental estrogens -- the female hormone-mimicking chemicals found in nature and in such man-made substances as pesticides and plastics -- threaten to make us infertile? Are environmental estrogens associated with endometriosis and fibroids in women? What role do they play in cancer and birth defects?

How do we use available science to make credible regulatory decisions? These are some of the questions facing scientists and policy makers at NIEHS' Conference on Estrogens in the Environment IV.

Dr. John H. Gibbons, assistant to the President for science & technology and director of the White House Office of Science and Technology Policy, will provide the Administration's environmental health priorities -- including where environmental estrogens fit in the picture -- at the opening session, 9 a.m. to noon Monday July 21, of the NIEHS Conference on Estrogens in the Environment IV at the Crystal Gateway Marriott, Arlington, Va.

The Monday afternoon session, 1 p.m. to 5:30, will be on "Trends/Health Effects" with such scientists as John McLachlan of Tulane and Dolores Lamb of Baylor; "Mechanistic Considerations" will be the theme from 8:30 a.m. to noon Tuesday; "Endometriosis and Fibroids" will be among the topics Tuesday afternoon; Government and private scientists will discuss "Linking Science and Policies for Protecting Public Health" from 8:30 a.m. to noon Wednesday, the final session.

The media are welcome. For further information call Alma Britton, the National Toxicology Program Liaison and Scientific Review Office, at 919/541-0530. Once the meeting starts, you can call Ms. Britton or Bill Grigg (NIEHS Communications) or Sandy Lange (NTP Liaison Office) via cell phones at (919) 621-8361 or 8362.