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Research Programs
Endocrine Disruptors Effects Research
Endocrine Disruptors
Effects Research
Low-Dose Studies and Effects of Multiple EDCs
For the most part, the data linking environmental pollutants to endocrine disruption comes from studies of wildlife species with relatively high exposures to specific compounds such as DDT, PCBs, or dioxins. While there are exceptions to this generalization, relatively little is known about the causes of endocrine disruption and the concentrations of EDCs that can induce effects. In response to this lack of information, EPA scientists plan to use models of diseases (e.g., testicular and breast cancer, infertility, and prostate cancer) to test the hypothesis that low doses of EDCs, such as those to which people are exposed in today's environment, can induce effects in humans similar to those observed in studies where the doses of EDCs were much higher.
EPA researchers are also interested in determining the effects of exposure during critical periods of development (e.g., during gestation, early childhood, and puberty) and on critical systems such as the immune system, the central nervous system, and the reproductive system. Additionally, EPA scientists recognize that, in most cases, humans and other organisms are exposed to mixtures of chemicals, not to individual EDCs, so they are interested in gaining a better understanding of the combined effects of exposure to mixtures of chemicals. Such exposures may be additve or they may be less than additive in causing EDC effects. However, it is possible that exposure to a mixture of EDCs could produce an effect greater than would be predicted by simply adding the individual effects together in what could be termed a "synergistic" or "1 + 1 = 3" effect.
