What are 'forever chemicals'? Inside New York's lawsuit against 3M and DuPont
New York's attorney general has sued 3M, DuPont and several other manufacturers, accusing them of causing a public nuisance by selling products containing PFAS chemicals that they knew were toxic, even as some companies began quietly phasing the substances out. The lawsuit is the latest in a wave of legal action across the US targeting the chemical industry over so-called "forever chemicals."
PFAS, short for per- and polyfluoroalkyl substances, are a large family of manufactured chemicals first developed in the mid-20th century for their remarkable ability to resist heat, water and oil. That made them prized additives in everything from non-stick cookware and waterproof clothing to firefighting foam and food packaging.
The nickname "forever chemicals" comes from the carbon-fluorine bond at the core of PFAS molecules, one of the strongest bonds in organic chemistry. That same property that makes PFAS so useful industrially also means the chemicals resist natural breakdown, persisting in soil, water and the human bloodstream for years or even decades after exposure.
Research over the past two decades has linked certain PFAS chemicals to a range of health concerns, including increased cholesterol levels, changes in liver function, decreased fertility, developmental effects in children, and elevated risk of some cancers, according to reviews by health and environmental agencies. Scientists caution that risk levels vary significantly depending on which specific PFAS compound and how much exposure is involved.
New York's lawsuit alleges that 3M and DuPont knew about potential health and environmental risks associated with PFAS for decades before that information became public, and continued selling PFAS-containing products regardless. Both companies have faced similar accusations in other lawsuits and regulatory actions across the United States in recent years.
The US Environmental Protection Agency has separately found that food is one of the largest sources of everyday PFAS exposure for most people, alongside contaminated drinking water in some regions. Testing has detected the chemicals in a range of packaged and prepared foods, sometimes at levels researchers say are equivalent to drinking multiple servings of contaminated water.
Despite that, the US Food and Drug Administration has separately rejected a legal petition asking it to set formal limits on PFAS levels in food, a decision public health advocates have criticized as a missed opportunity to address one of the chemicals' most significant exposure routes.
Some manufacturers have already begun phasing out certain PFAS compounds, particularly the older, longer-chain variants most strongly linked to health concerns, replacing them with newer formulations the industry describes as safer. Independent researchers say the health effects of many newer replacement chemicals remain far less studied.
For consumers, avoiding PFAS entirely is difficult given how widely the chemicals have been used across consumer products for decades. Environmental health experts generally recommend checking product labels for PFAS-related terms, favoring PFAS-free cookware and food packaging where available, and following any local drinking water advisories, while cautioning that individual choices alone cannot fully offset chemicals now present throughout the environment.
The New York case, alongside similar litigation in other states, will likely take years to resolve. Legal experts say the outcome could shape how much manufacturers are required to disclose about chemical risks going forward, and how much liability companies face for contamination that, by design, does not go away.
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