MD, SC lose bid to try PFAS contamination cases in state courts

Maryland and South Carolina will have to press their cases for PFAS damages against 3M Co. in federal court, after the U.S. Supreme Court declined to hear their petition to have the lawsuits returned to their respective state courts.

The justices, without comment, declined Monday to hear an appeal of a 4th U.S. Circuit Court of Appeals ruling against the states. That March 2025 ruling said that because 3M made some of the PFAS-containing materials at the direction of the federal government, it could invoke the “federal officer removal statute” and have the cases heard in federal, not state, court.

The cases involve four separate lawsuits filed by the states to recover damages for contamination by PFAS — per- and polyfluoroalkyl substances that have been linked to a range of human health problems. Known informally as “forever chemicals” because they are resistant to breaking down in nature, PFAS is used in a wide variety of products, from water-repellent clothing to nonstick cookware and stain-resistant fabrics.

It is also a key ingredient in aqueous film-forming foam — AFFF — a firefighting foam especially effective in battling fuel fires, and often used on military bases, airfields and ships. According to court documents, 3M was a major manufacturer of PFAS for more than 6o years; for more than 30 years, it produced AFFF to military specifications for the Navy. This “MilSpec AFFF” required the use of PFAS.

“During that time, 3M closely followed the military’s specifications in satisfying its federal contracts — which mandated that any AFFF produced for the U.S. military contain PFAS,” 3M said in its filing with the Supreme Court. “The military used MilSpec AFFF on military bases across the country, including at numerous sites in Maryland and South Carolina.”

While the Pentagon dropped the specific PFAS requirement for the firefighting foam in 2019, “the Department of Defense acknowledged in the most recent MilSpec, it is not possible for manufacturers to eliminate PFAS from their AFFF entirely” and still meet military specifications. And once “PFAS compounds are detected in water or soil, there is no reliable way to distinguish between PFAS contamination stemming from MilSpec AFFF and non-MilSpec AFFF, or from AFFF and non-AFFF products,” the company said.

With that in mind, Maryland sued 3M in May 2023 for PFAS contamination and damage to state waterways and wildlife. But the state filed two suits — one for PFAS contamination and a second specifically for AFFF contamination. South Carolina followed suit a short while later with a similar two-track strategy, separately targeting PFAS and AFFF.

In their petition to the Supreme Court, the states said South Carolina’s PFAS suit “expressly excludes” AFFF and that the state was “not seeking to recover through this Complaint any relief for contamination or injury related to AFFF or AFFF products used at airports, military bases, or certain industrial locations.”

Likewise Maryland said its PFAS lawsuit “does not … seek any remediation, restoration, damages, or any other relief related to any PFAS contamination caused by AFFF or fluorosurfactants when used as ingredients of AFFF. The State’s claims with respect to AFFF are the subject of a separate action.”

3M quickly moved to have the AFFF lawsuits removed to federal court under the federal officer removal statute. It says “a private defendant may remove a state-court case ‘relating to any act’  the defendant took under the federal government’s direction.”

But 3M also said the PFAS suits should be removed to federal court, since it would be impossible to determine if contamination came from a consumer use of PFAS or from AFFF that was produced at the direction of the government. The states had filed “nearly identical suits,” but split them in two to avoid federal jurisdiction on one, the company said.

U.S. District Courts in each state agreed with the states, and ordered the PFAS cases back to state courts in Maryland and South Carolina for hearing. But the 4th U.S. Circuit Court of Appeals, which combined the South Carolina and Maryland cases, disagreed.

In a dissent, Circuit Judge Henry Floyd said 3M’s argument was too tenuous to justify federal jurisdiction, and that the majority’s ruling risked sweeping lawsuits “properly before state courts” into the federal system.

“In this case, 3M seeks to remove a claim seeking recovery for pollution from products made for and sold on the consumer market; the majority concludes that the causal nexus is satisfied because the resulting pollutants are commingled in the environment. I believe that this connection is too tenuous to support removal,” Floyd wrote.

“As I see it, the court reads the nexus requirement so broadly as to move toward foreclosing state courtrooms to plaintiffs bringing state-law claims against defendants, when those defendants in turn identify even the slightest connection between the claims at issue at work they have performed as government contractors,” he said in dissent. “Given what I see as the scant connection shown between 3M’s production of consumer products and its AFFF production, I would trust the courts of Maryland and South Carolina to hear these cases and ensure any liability is apportioned properly.”

The Maryland Attorney General‘s Office declined to comment on the Supreme Court’s decision to let the 4th Circuit ruling stand. Requests for comment from 3M were not returned.