EPA drafts first drinking-water contaminant list to include microplastics and pharmaceuticals

The Environmental Protection Agency has issued a draft drinking-water contaminant list that includes microplastics and pharmaceuticals for the first time, opening the door to possible future regulation.

The draft Sixth Contaminant Candidate List, published on April 2, also includes PFAS, disinfection byproducts, 75 chemicals and nine microbes. EPA says the list is a screening and prioritization step under the Safe Drinking Water Act, not a final drinking-water standard.

According to the agency, contaminants on the list are not currently subject to proposed or promulgated national primary drinking-water regulations. The draft is now open for public comment through June 1, 2026.

EPA’s move came after Reuters and AP reported the draft action on Thursday. AP said the agency was putting microplastics and pharmaceuticals into the drinking-water review process, which could set up later decisions on whether to regulate them.

The inclusion of microplastics and pharmaceuticals is notable because it pushes both categories into the federal rulemaking pipeline for the first time. Any future regulation would still depend on what EPA concludes after the comment process and subsequent review.

For now, the action is an early step, but one that could shape drinking-water policy in the months ahead.