An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Regulation Timeline: Contaminants Regulated Under the Safe Drinking Water Act

The drinking water regulation timeline shows when more than 90 drinking water contaminants were regulated, revised, or removed from regulation.  For each regulation, the table contains infomation including the month and year of Federal Register publication, the name of the regulation, the number of contaminants in the regulation, and the names of contaminants regulated (or deleted) under that regulation.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.