The Agency for Toxic Substances and Disease Registry, ATSDR, is an agency of the U.S. Public Health Service. It was established by Congress in 1980 under the Comprehensive Environmental Response, Compensation, and Liability Act, also known as the Superfund law. This law set up a fund to identify and clean up our country's hazardous waste sites.

The Environmental Protection Agency, EPA, and the individual states regulate the investigation and clean up of the sites.

Since 1986, ATSDR has been required by law to conduct a public health evaluations at each of the sites on the EPA National Priorities List. The aim of these evaluations is to find out if people are being exposed to hazardous substances and, if so, whether that exposure is harmful and should be stopped or reduced.

If appropriate, ATSDR also conducts public health evaluations when petitioned by concerned individuals or organizations. Public health evaluations are carried out by environmental and health scientists from ATSDR and from the states with which ATSDR has cooperative agreements.

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As the first step in the evaluation, ATSDR scientists review environmental data to see how much contamination is at a site, where it is, and how people might come into contact with it.

Generally, ATSDR does not collect its own environmental sampling data but reviews information provided by EPA, other government agencies, businesses, and the public. When there is not enough environmental information available, ATSDR may indicate what further sampling data is needed.

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Health Effects

If the review of the environmental data shows that people have or could come into contact with hazardous substances, ATSDR scientists then evaluate whether or not there may be any harmful effects from these exposures.

The report focuses on public health, or the health impact on the community as a whole, rather than on individual risks. Again, ATSDR generally makes use of existing scientific information, which can include the results of medical, toxicologic and epidemiologic studies and the data collected in disease registries. The science of environmental health is still developing, and sometimes scientific information on the health effects of certain substances is not available. When this is so, the report may suggest what further research studies are needed.

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The report presents conclusions about the level of health threat, if any, posed by a site and recommends ways to stop or reduce exposure in its public health action plan.

ATSDR is primarily an advisory agency, so usually these reports identify what actions are appropriate to be undertaken by EPA, other responsible parties, or the research or education divisions of ATSDR. However, if there is an urgent health threat, ATSDR can issue a public health advisory warning people of the danger. ATSDR can also authorize health education or pilot studies of health effects, full-scale epidemiology studies, disease registries, surveillance studies or research on specific hazardous substances.

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Interactive Process

The health assessment is an interactive and iterative process. ATSDR solicits and evaluates information from numerous city, state and federal agencies, the companies responsible for cleaning up the site, and the community. It then shares its conclusions with them. Agencies may be asked to respond to an early version of the report to make sure that the data they have provided is accurate and current.

When informed of ATSDR's conclusions and recommendations, sometimes the agencies will begin to act on them before the final release of the report.

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ATSDR also needs to learn what people in the area know about the site and what concerns they may have about its impact on their health. Consequently, throughout the evaluation process, ATSDR actively gathers information and comments from the people who live or work near a site, including residents of the area, civic leaders, health professionals and community groups.

To ensure that the report responds to the community's health concerns, an early version may also be distributed to the public for their comments. All the comments received from the public are responded to in the final version of the report.

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If, after reading this report, you have questions or comments, we encourage you to send them to us. Letters should be addressed as follows:

ATTENTION: Associate Director for Science
Agency for Toxic Substances and Disease Registry
4770 Buford Highway (Mailstop S102-2)
Chamblee, GA 30341

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Page last reviewed: February 10, 2021