Follow-Up: Multi-State Coalition Expands Support For Microplastics Regulation, Urging USEPA To Include Microplastics In Both CCL 6 And UCMR 6

As discussed in our prior microplastics client alert, in November 2025, the governors of seven states, including New Jersey, jointly petitioned (the Petition) the U.S. Environmental Protection Agency (USEPA) to include microplastics in the agency’s Sixth Unregulated Contaminant Monitoring Rule (UCMR) for drinking water.¹ The Petition was anchored in the SDWA, which requires USEPA to include in the UCMR any contaminant recommended by at least seven governors unless USEPA determines that doing so would prevent the listing of contaminants of higher public health concern.

Since the publication of that alert, two significant developments have occurred. First, on April 6, USEPA published its draft Contaminant Candidate List (CCL) 6, which includes microplastics as a chemical group.^2,3 Second, on June 5, attorneys general from 15 states and the District of Columbia, led by New Jersey Attorney General Jennifer Davenport, jointly submitted comments on the draft CCL 6 (Comment Letter),