Contaminant Candidate List (CCL) and Regulatory Determination

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. The Agency 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.