The short answer
Some paper food packaging used PFAS coatings to stop grease and water from soaking through. FDA raised safety concerns, industry phased the substances out in two waves, and in February 2024 FDA announced these grease-proofing agents are no longer sold into the U.S. market. In January 2025 FDA declared 35 related food contact notifications no longer effective.
PFAS grease-proofing agents were applied to paper and paperboard packaging to prevent grease, oil or water leaking through.
FDA states this type of use can result in dietary exposure through transfer or migration into food.
Long-chain PFAS were withdrawn or revoked between 2011 and 2016, and use stopped in November 2016.
FDA identified safety concerns with 6:2 FTOH in 2020, and manufacturers began a three-year phase-out in January 2021.
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Why a paper bag needed a coating
A microwave popcorn bag has an awkward job. It has to hold oil, get very hot, and still arrive at your hands as a paper bag rather than a greasy mess. Manufacturers solved that with grease-proofing agents — coatings applied to paper and paperboard packaging to prevent grease, oil or water from leaking through.
Some of those coatings belonged to a chemical family called PFAS. That is where the story starts.
The problem FDA identified
FDA's concern was not the coating sitting quietly on the paper. It was movement. Because of how these substances are built and how they are applied, FDA states that this type of use can result in dietary exposure to the substance from the transfer or migration into the food.
FDA's wording is that this type of use can lead to transfer into food.
Two phase-out waves
The response happened in two waves, and the timeline is clearer than most regulatory stories.
The long-chain wave. In the early 2000s, new studies raised safety questions about PFAS with 8 or more carbon atoms. Between 2011 and 2016, long-chain PFAS were phased out of these uses. FDA states that by November 2016 they were no longer used in food contact applications.
The short-chain wave. Attention then turned to a shorter compound known as 6:2 FTOH. FDA identified safety concerns with it in 2020. In January 2021 manufacturers began a three-year phase-out, with existing stocks expected to be exhausted by June 2025.
Two announcements closed the loop. In February 2024, FDA announced that PFAS grease-proofing agents are no longer being sold into the U.S. market. In January 2025, FDA issued a Federal Register notice that 35 food contact notifications related to PFAS were no longer effective — meaning the authorizations behind those specific uses no longer stand.
What FDA did not say
This is the part that gets stretched online. FDA's page documents safety concerns, dietary exposure through migration, and a completed phase-out. It does not state that these grease-proofing agents cause cancer, and this article will not fill that gap with something the source did not say.
A substance can be withdrawn from the market because concerns were raised, without a regulator ever concluding it caused a specific disease.
That is not a loophole. It is how precautionary regulation is supposed to work — you can act on concern without waiting for proof of harm.
Where popcorn bags fit
FDA's phase-out page describes the category: grease-proofing agents on paper and paperboard packaging. FDA's page speaks of the packaging category. It does not mention microwave popcorn bags by name, so this article cannot say which products used these coatings.
What to do with this at home
Honestly, not much is required of you. The market action already happened. The substances were phased out, the authorizations were pulled, and FDA announced the sales had ended.
If you want a rule of thumb for the next food packaging headline that lands in your feed, try this one: check whether the agency's own page describes a concern or a conclusion, and check the dates. In this case the dates tell a story of steady tightening across two decades, ending in 2024 and 2025.
If food worries have grown during cancer treatment, ask your care team whether a dietitian can help.
Common questions
Do popcorn bags still have these coatings?
FDA announced in February 2024 that PFAS grease-proofing agents are no longer being sold into the U.S. market. Existing stocks were expected to be exhausted by June 2025 under the short-chain phase-out timeline.
Did FDA say these coatings cause cancer?
The page describes safety concerns and dietary exposure through migration into food, and it documents the phase-out. It does not state that these substances cause cancer.
Why were popcorn bags coated at all?
Grease-proofing agents were applied to paper and paperboard packaging to keep grease, oil or water from leaking through the package.
What does it mean that a food contact notification is no longer effective?
It means the authorization that allowed those specific uses no longer stands. FDA issued that notice for 35 PFAS-related notifications in January 2025.
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Sources last checked: 2026-10-02 what this meansLast updated: 2026-08-11Next planned review: 2027-08-11
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Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes, and this is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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