title: Introduction to the symposium.
authors.affiliation: National Center for Environmental Assessment, U.S. Environmental Protection Agency, Washington, DC 20460, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Kimmel
mesh_terms: D000013:Congenital Abnormalities / Q000209:etiology*; D004781:Environmental Exposure / Q000009:adverse effects*; D004812:Epidemiologic Methods; D006801:Humans; D018570:Risk Assessment