The Trump administration has generally favored reducing environmental regulations. Yet on April 2, 2026, the Environmental Protection Agency (EPA) and the Department of Health and Human Services (HHS) made coordinated announcements signaling that microplastics—tiny plastic particles found in everything from tap water to human blood—would receive new federal attention. EPA moved to designate microplastics a “priority contaminant group” under the Safe Drinking Water Act’s Contaminant Candidate List process, while HHS launched a $144 million research program to study microplastics in the human body. Neither action regulates microplastics directly. But both represent a meaningful shift in federal policy toward a pollutant that, until recently, barely registered on the regulatory agenda. This post examines what the agencies announced, what drove them to act, and what remains undone.

Our Microplastic Problem

Plastic pollution has become one of the defining hazards of our time. Microplastics are an especially pervasive and troublesome form of plastic pollution. Smaller than 5 millimeters, microplastics include both plastics intentionally designed to be small, such as plastic pellets or nurdles, and plastic particles that fragment from larger pieces of plastic. Plastic products are embedded in modern society, and as a result, microplastics are found everywhere: in the air, water, soil, and the tissue of humans and animals. While the impact of microplastics on marine ecosystems is well documented, the science regarding human health impacts is still emerging. Recent scientific studies have linked microplastics to heart disease, infertility, and cognitive decline, among other conditions.

Despite their ubiquity, microplastics have largely escaped regulation. Apart from the Microbead-Free Waters Act of 2015, which bans microbeads in rinse-off cosmetics, no federal legislation directly regulates microplastics. 

EPA and HHS Announcement

That may be beginning to change. On April 2, 2026, the EPA and HHS issued coordinated announcements on microplastics. EPA announced it would designate microplastics a “priority contaminant group” in its draft Sixth Contaminant Candidate List (CCL 6). The CCL is a critical tool under the Safe Drinking Water Act (SDWA) that drives research, funding, and regulation decisions on emerging threats to drinking water. Including microplastics in the CCL does not guarantee their regulation, but it is an important first step.

In addition to the priority contaminant group designation by EPA, HHS announced the establishment of Systematic Targeting Of MicroPlastics (STOMP)—a nationwide program to develop tools for measuring, researching, and affordably removing microplastics and nanoplastics (MNPs) in the human body. The $144 million program will be administered by the Advanced Research Projects Agency for Health (ARPA-H) within HHS.

The announcement by EPA and HHS to study microplastics does not mean that the regulation of microplastics is imminent. Advocates like the Plastic Pollution Coalition acknowledge that official recognition of the harm of microplastics is a positive step. Still, the coalition asserts that the scientific evidence is sufficient and human health harms are significant enough for policymakers to act now.

What Prompted the EPA/HHS Announcement?

In an administration generally skeptical of new environmental regulation, what prompted EPA and HHS to act? Several forces likely offered motivation.

Litigation

Microplastics-based product liability claims are beginning to emerge in the courts. For example, in Cortez v. Handi-Craft Co. (2024), plaintiffs alleged that microplastics leached from baby bottles when heated. A similar allegation was made in Miller v. Philips N. Am. LLC (2025). While Cortez was dismissed for failure to allege a specific threshold of harm, Miller survived a motion to dismiss. The Miller court found that the scientific literature cited by the plaintiffssufficiently supported allegations that the defendant’s products posed anunreasonable risk of harm from microplastics.    

State Legislation

Several states have introduced or enacted legislation requiring agencies to monitor and quantify microplastics in drinking water. For example, in 2020, California became the first state to enact legislation requiring its State Water Resources Board to standardize testing and monitoring for microplastics in drinking water. New Jersey enacted a similar law in 2023, and a bill to study microplastics in drinking water was introduced in Virginia in 2024.

Congress

In the summer of 2025, two bills—the Microplastics Safety Act and the Plastic Health Research Act—were introduced in the House, calling for studies on the human health impacts of microplastic exposure.

Petition from State Governors            

Perhaps the strongest catalyst for a federal response was a petition from state governors. In November 2025, a coalition of governors from seven states—Connecticut, Maine, Maryland, Massachusetts, New Jersey, New York, and Washington—petitioned EPA to include microplastics in the next Unregulated Contaminant Monitoring Rule (UCMR) under the Safe Drinking Water Act, anticipated in 2027. The UCMR is issued every five years to monitor emerging contaminants in drinking water and represents the first formal step toward establishing federal regulatory standards. The governors’ petition reflects growing state pressure for federal action. Specifically, the petition notes that “given the significant health risks microplastics may raise, and the lack of consensus on how microplastics should be defined and regulated, this is the optimal time for EPA to lead the conceptualization and data collection efforts nationwide to begin protecting the people of the United States from microplastics.” Under the Safe Drinking Water Act and its regulations, EPA must include in the UCMR any contaminant recommended by a petition of at least seven governors when there is a high risk to public health.

Next steps

Publication of the draft CCL 6 in the Federal Register will open a 60-day public comment period. Interested parties may submit comments to docket number EPA-HQ-OW-2022-0946 at regulations.gov. EPA will also consult with its independent Science Advisory Board before finalizing the list later this year.

What the Commitments Don’t Do

Despite acknowledging the problem with microplastics, the EPA and HHS commitments do not regulate the production, use, or disposal of plastic. Plastic production is expected to double by 2050,  with adverse health impacts doubling by 2040. In my most recent article, Our Microplastic Problem, I examine how state and local entities are addressing the microplastic problem in the absence of sweeping federal regulations. The article highlights “micro-solutions” or targeted, practical state and local interventions that address microplastic pollution across the plastic lifecycle. From product bans to design changes and disclosure requirements, micro-solutions offer a path forward in an era of federal inaction and demonstrate how smaller-scale efforts can help drive environmental change. Addressing plastic pollution and minimizing its impact will ultimately require interventions across the entire lifecycle of plastic, governing its production, use, and disposal, not merely microplastic monitoring.

Sarah J. Morath is Professor of Law at Wake Forest University School of Law.