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What EPA Does With the CCL

Scientist performing chemical analysis in a laboratory

Developing the Contaminant Candidate List (CCL) is the first step in evaluating drinking water contaminants. EPA continues to further evaluate contaminants on the list by:

Continuing to collect data and encourage further research on listed contaminants to better understand potential health effects and at what levels they occur in drinking water.
Periodically making Regulatory Determinations for CCL contaminants with sufficient health and occurrence data.

What EPA Does With the CCL

Contaminant Candidate List (CCL) and Regulatory Determination