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Executive Summary
Pages 1-9

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From page 1...
... In addition, the effects of in utero exposure to the potent synthetic estrogen diethylstilbestrol (DES) in the offspring of treated women and the replication of these effects in mice have focused attention on embryonic development as a target for the potential disruptive effects of environmental agents with hormonal activity.
From page 2...
... The committee focused its attention on compounds that have been reported to induce reproductive changes, developmental defects, neurobehavioral abnormalities, immunologic deficits, carcinogenesis, and ecologic effects. It became clear as the work of the committee progressed that limitations and uncertainties in the data could lead to different judgments among committee members with regard to interpreting the general hypothesis, determining appropriate sources of information, evaluating the evidence, defining the agents of concern, and evaluating environmental and biologic variables.
From page 3...
... Underlying mechanisms of action should be investigated with both in vitro and in vivo systems that can detect diverse responses. Health Effects Because of the difficulties associated with establishing cause and effect in humans and wildlife populations, for which exposure to HAAs is often the result of unintended releases of chemicals into the environment and involves exposures to multiple chemicals, the committee evaluated laboratory studies on individual HAAs in conjunction with available data from human studies and from field observations of wildlife.
From page 4...
... ; increased egg and fry mortality in Great Lakes trout and salmon; thyroid enlargement in Great Lakes salmon; and changes in plasma sex-steroid concentrations, decreased egg and gonad size, and delayed sexual maturity in white suckers exposed to effluents from paper mills along Lake Superior. Laboratory experiments with specific HAAs found in those effluents and polluted waters have produced effects consistent with those wildlife observations.
From page 5...
... , including small penis size and abnormal testes in males and abnormal ovaries in females, are consistent with structural and functional reproductive abnormalities that occur following perinatal exposure of laboratory rodents to estrogenic and antiandrogenic chemicals. Recommendations Wildlife and human populations should continue to be monitored for abnormal development and reproduction.
From page 6...
... have been associated with tumors of the thyroid, pituitary, or renal glands in particular species and strains of laboratory animals, HAAs in general have not been shown to induce tumors in reproductive or other endocrine organs after postnatal exposure, but the suitability of animal models might be in question. An evaluation of the available studies conducted to date does not support an association between adult exposure to DDT, DDE, TCDD, and PCBs and cancer of the breast.
From page 7...
... Ecologic Effects Environmental HAAs probably have contributed to declines in some wildlife populations, including fish and birds of the Great Lakes and juvenile alligators of Lake Apopka, and possibly to diseases and deformities in mink in the United States, river otters in Europe, and marine mammals in European waters. Such contaminants, along with inbreeding, might have contributed to the poor reproductive success of the endangered Florida panther and the increased embryonic mortality of the snapping turtle in the Great Lakes.
From page 8...
... Recommendations Long-term studies of populations subjected to HAA exposures are needed to assess the effects of these chemicals in altering population size, age structure, and dynamics. Observational and experimental studies of the linkages between chemical exposures and alterations of key aspects of life histories should be undertaken to understand how chemical exposures affect long-term ecologic attributes of natural systems.
From page 9...
... Recommendations Better monitoring of contaminated media is required to determine environmental concentrations of HAAs and to assess the persistence and recycling of HAAs in and between the various environmental media. Background concentrations of HAAs in humans, particularly in adipose tissue and blood, and other biota need to be established.


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