Thinx and PFAS: What Happened?

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Quick answer

Thinx settled a class action lawsuit that claimed its period underwear contained PFAS, a group of man-made chemicals. The deal was worth up to $5 million. A federal court gave it final approval in June 2023. Thinx denied the claims and did not admit any wrongdoing.

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Woman reading news on her phone about the Thinx PFAS lawsuit and settlement
  • A class action lawsuit claimed Thinx underwear had PFAS.
  • Thinx settled for up to $5 million and denied the claims.
  • A federal court gave final approval on June 8, 2023.
  • Thinx agreed to take steps to help make sure PFAS aren't added on purpose.
  • You can ask any brand for its PFAS lab results.
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Thinx and PFAS: the timeline

  • January 2020: Sierra magazine reported that a lab test found PFAS in Thinx underwear.
  • May 2022: Buyers filed a class action lawsuit in federal court in New York.
  • December 2022: The court gave the settlement early approval.
  • June 8, 2023: The court gave the settlement final approval.

What did the lawsuit claim?

The lawsuit claimed Thinx underwear had PFAS. It said Thinx led buyers to believe the underwear was safe and free of harmful chemicals.

Thinx denied all the claims. In the deal, Thinx did not admit any fault or wrongdoing. The case ended in a settlement, not a trial.

What did Thinx agree to?

Thinx agreed to pay up to $5 million. People who bought Thinx underwear from November 2016 to November 2022 could claim up to $21 in cash or a discount voucher. The deadline to file was April 12, 2023.

Thinx also agreed to take steps to help make sure PFAS aren't added on purpose at any stage of making its period underwear. Its suppliers must also confirm they don't add PFAS on purpose.

Should I stop wearing Thinx?

That's your choice. Today, Thinx says on its website that PFAS are not part of its product design. It says it uses outside labs to test for PFAS.

Poison control experts say there's no proof that PFAS in period underwear harms health. If you have questions, ask Thinx for its latest lab results.

Woman by a window with coffee, thinking about whether to stop wearing Thinx period underwear

How to check any brand for PFAS

  • Ask for recent PFAS test results from an outside lab.
  • Ask if the test covered every layer of the underwear.
  • Ask if PFAS are added on purpose.
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Common questions

Did Thinx have PFAS?

A lawsuit claimed it did. Thinx denied the claims and settled without admitting wrongdoing. The case ended in a settlement, not a trial.

How much was the Thinx settlement?

Up to $5 million. Buyers could claim up to $21 in cash or a 35% off voucher.

Can I still file a Thinx claim?

No. The deadline to file a claim was April 12, 2023.

Is Thinx period underwear safe to wear?

The case was settled, so its claims were never decided in court. Thinx denied them. Poison control experts say there's no proof that PFAS in period underwear harms health.

Should I stop wearing Thinx?

That's up to you. Thinx says PFAS are not part of its product design and that it tests with outside labs. You can ask Thinx for its latest results.

More guides

See all guides: Period Underwear Guide: Every Question Answered

Sources

  1. NPR: Thinx settled a lawsuit over chemicals in its period underwear (January 19, 2023)
  2. Dickens v. Thinx Inc. Settlement Website
  3. Dickens v. Thinx Inc.: Settlement Agreement and Release
  4. CourtListener: Dickens v. Thinx, Inc., 1:22-cv-04286 (S.D.N.Y.)
  5. Sierra Club: Sierra Magazine Investigation Leads to Thinx Class Action Settlement (January 2023)
  6. Thinx: Product Safety Standards (checked October 2026)
  7. Poison Control (National Capital Poison Center): Is Period Underwear Safe to Use?

Updated by the Kischt team.

This page is general information, not medical advice. See a doctor if you are worried about your health.

Returns: you have 30 days after you get your order to request a refund. Details are in the return policy.