EPA announces drinking water contaminant candidate list
On July 12, 2021, EPA announced the drinking water draft Contaminant Candidate List 5 (CCL 5). The CCL is the most updated list of known or anticipated contaminants to public water systems that are not yet regulated. Once finalized, EPA will use this list determine whether to begin regulating a specific contaminant. The draft list includes 69 chemicals or chemical groups and 12 microbes. The chemicals or chemical groups include 66 chemicals and three chemical groups (per- and polyfluoroalkyl substances (PFAS), cyanotoxins, and disinfection byproducts (DBPs)). The microbes include 8 bacteria, 3 viruses, and 1 protozoa.
EPA will accept public comments on the list for 60 days after publication in the Federal Register (Docket ID Number EPA-HQ-OW-2018-0594).
The Safe Drinking Water Act (SDWA) requires EPA to develop a list of unregulated contaminants in public drinking water systems every five years. EPA has previously completed four rounds of CCLs, with this most recent list being the fifth. Under the SDWA, EPA must determine whether to regulate at least five contaminants from the CCL. When evaluating the CCL, EPA must determine if three specific criteria are met, warranting regulation of that chemical or chemical group. These are:
- The contaminant may have an adverse effect on the health of persons;
- The contaminant is known to occur, or there is a substantial likelihood that the contaminant will occur, in public water systems with a frequency and at levels of public health concern; and
- The EPA Administrator determines the regulation of the contaminant presents meaningful opportunity to protect public health.