Per- and polyfluoroalkyl substances, known as PFAS, are a group of man-made chemicals that have been used since the 1940s in everything from non-stick cookware to firefighting foam. These chemicals do not break down in the environment. They accumulate in the human body. And they have been linked to cancer, liver damage, thyroid disease, and developmental problems. When PFAS leach into groundwater and contaminate drinking water wells or public water systems, the legal question becomes brutally simple: who is financially responsible for the cleanup and the health damage?
The answer depends on the source of the contamination, the conduct of the responsible party, and the legal theories a plaintiff can use. In the United States, most PFAS liability cases fall under three common legal theories: negligence, nuisance, and strict liability. Each has different requirements, and each comes with different potential payouts.
Negligence is the most straightforward theory. To win a negligence case, you must prove that the defendant owed you a duty of care, that they breached that duty, and that the breach directly caused your injury. For example, if a chemical plant knowingly dumped PFAS waste into an unlined pond, and that waste seeped into the aquifer supplying your well, the plant likely breached its duty to operate safely. The key is proving the defendant knew or should have known the risk. Many PFAS cases succeed on negligence because the chemical industry had internal documents showing the dangers of PFAS decades ago, yet continued to dump or discharge the chemicals without warning the public.
Nuisance is another common theory. Nuisance law says you have a right to enjoy your property without unreasonable interference. PFAS contamination makes your water unusable for drinking, bathing, or gardening. That is a clear interference with your property rights. Public nuisance claims can be brought by governments on behalf of entire communities. Private nuisance claims are brought by individual landowners. The advantage of nuisance is that you don’t always need to prove the defendant acted negligently. You just need to show the contamination substantially and unreasonably interfered with your use of the land.
Strict liability is the heaviest hammer. Under strict liability, a defendant can be held responsible even if they took every possible precaution. This theory applies to abnormally dangerous activities. Courts have ruled that handling and disposing of hazardous substances like PFAS fits that definition. Strict liability means a plaintiff does not have to prove the defendant was careless. They only have to prove the defendant created the hazard and that hazard caused the harm. This makes strict liability a powerful tool, especially when the defendant is a large corporation with deep pockets.
Beyond these common law theories, there are also federal and state statutes that impose liability. The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, also known as Superfund) allows the government to force responsible parties to clean up contaminated sites. In 2022, the EPA designated two of the most common PFAS chemicals—PFOA and PFOS—as hazardous substances under CERCLA. That means polluters can now be ordered to pay for testing, cleanup, and restoration of affected drinking water sources. It also means third parties, like water utilities, can sue polluters to recover the costs of filtering PFAS out of municipal water supplies.
Recent high-profile cases illustrate how these legal theories play out in real life. In 2023, the chemical giant 3M agreed to pay more than $10 billion to settle PFAS lawsuits with public water systems across the United States. The settlement covered claims that 3M’s firefighting foam and other products contaminated drinking water sources. The company did not admit liability, but the sheer size of the payout shows the scale of potential damages. DuPont and its spin-off Chemours have also paid billions in settlements and judgments, including a $671 million settlement with the state of Ohio and a $50 million verdict against DuPont in a personal injury case brought by a Ohio man who developed cancer after drinking PFAS-contaminated water.
For individuals, the path to compensation is harder but not impossible. Most personal injury cases for PFAS exposure are still being litigated. The science connecting PFAS to specific diseases is strong, but proving causation in court requires expert testimony and medical records. Class action lawsuits often make sense for communities where everyone drank the same contaminated water. But class actions can take years, and individual settlements may be modest compared to the health care costs involved.
If you suspect your drinking water is contaminated with PFAS, your first step is to get your water tested. Many states offer free or low-cost testing in known contamination zones. If PFAS are detected above the EPA’s health advisory levels, you need to document everything: test results, medical symptoms, property values, and any communications with the potential polluter. Then contact an attorney who handles environmental contamination cases. Most work on contingency, meaning they only get paid if you win.
The legal landscape around PFAS is shifting fast. More states are setting their own maximum contaminant levels. The EPA is pushing forward with enforceable drinking water standards. And the number of lawsuits is growing every year. If you are a property owner, a business, or a municipal water supplier dealing with PFAS contamination, the law gives you several tools to force the polluter to pay. The trick is picking the right theory and assembling the right evidence. The money is there. The question is whether the legal system will deliver it in time.
