Animal studies demonstrate that early life exposure to hormonally active agents can lead to effects on mammary gland (MG) development, impaired lactation, and increased susceptibility to cancer (Fenton 2006).
Early life treatment with some hormonally active agents results in altered development of the MG in male and female rodents.
John Stegeman (email@example.com), a senior scientist at the Woods Hole Oceanographic Institution, served on the National Research Council Committee on Hormonally Active Agents
in the Environment.
Epidemiologic studies that consistently show increased risk associated with multiple sources of exposure to endogenous and pharmaceutical estrogen and other hormones strongly point to the hypothesis that hormonally active agents
in commercial products and pollution also increase risk.
In its review of hormonally active agents in the environment, the National Research Council (NRC 1999) recommended that further investigations of human exposure to natural and anthropogenic hormonally active agents be conducted to determine relative contributions of estrogen equivalents.
Although we recognize that hormonally active agents encompass a wide range of biochemical mechanisms, the focus of this paper is estrogenicity, because it is the hormonal mechanism for which most information exists.
There is growing concern that environmental factors including in utero and childhood exposures to hormonally active agents
may be modifying factors.
In collaboration with the CDC, the institute developed the Human Body Burden Project, collecting human exposure data to study human tissue concentrations of environmental contaminants including hormonally active agents
commonly called endocrine disruptors.