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Due to a lapse in appropriations, EPA websites will not be regularly updated. In the event of an environmental emergency imminently threatening the safety of human life or where necessary to protect certain property, the EPA website will be updated with appropriate information. Please note that all information on the EPA website may not be up to date, and transactions and inquiries submitted to the EPA website may not be processed or responded to until appropriations are enacted.

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Thimerosal in Vaccines

Some people are concerned about the use of thimerosal, a mercury-containing preservative, in vaccines. The U.S. Food and Drug Administration is the chief federal government agency responsible for regulating vaccines in the U.S. and therefore provides more detailed information on this subject.  To learn more about the use of thimerosal in vaccines, please see these resources:

Food and Drug Administration (FDA)

Centers for Disease Control and Prevention (CDC)