Knix Review, Is Knix Non-Toxic?
Knix averages 25 out of 100 on PFAS Authority's PFAS and toxin screen across the 8 Knix products graded as of October 2026, and none of them reach its 70 point pass mark.
Knix grades Poor on our four-band scale.
PFAS Authority is a scoring system, not a laboratory. We do not test products ourselves. Grades are model-based, built from published ingredients, materials, certifications, brand disclosures and third-party lab results where they exist. See the rubric.
What Knix says and does about PFAS
Knix agreed to pay $1.4 million, and up to $600,000 more if needed, to settle a class action over its marketing, and the settlement agreement requires it to remove references to its products being PFAS free from its website. Minnesota’s ban on intentionally added PFAS in menstruation products covers period underwear.
- Legal caseKnix agreed to pay $1.4 million, and up to $600,000 more if needed, to settle a class action over its marketing. Knix settlement site (archived page) ↗
- Legal caseThe Knix settlement agreement requires Knix to revise its website to remove references to its products being PFAS free. Settlement agreement via Truth in Advertising ↗
- Regulatory filingMinnesota’s ban on intentionally added PFAS, in force since 2025, covers menstruation products such as pads, tampons, period underwear and menstrual cups. Minnesota Pollution Control Agency ↗
Sources checked September 14, 2026. A brand statement is the company’s own claim, which we report but have not verified. Our grades are model-based estimates, not lab tests.
Knix is one of the brands we researched by hand for our record of what every brand has published about PFAS, where the same question is answered for each of them in one line.
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Does Knix have PFAS, by category
Which Knix products contain PFAS? Poor and Bad, we’d swap these
- Cotton/synthetic blend with proprietary waterproof/leak-resistant coating (unspecified)
- Undisclosed waterproof coating chemistry (likely fluorinated or silicone polymer). The proprietary coating is…
2 hazards checked on this product, all on its full breakdown.
Find an alternative on Amazon
- Cotton-polyester blend with waterproof treatment
- Fluorocarbon/Teflon-type coating in waterproof coating (undisclosed). Knix does not disclose waterproofing…
4 hazards checked on this product, all on its full breakdown.
Find an alternative on Amazon
- Fabric with waterproof/leak-resistant coating (unspecified chemistry)
- Teflon-type coating or fluorochemical fume risk (if Teflon-type coating-based coating). If the waterproof…
4 hazards checked on this product, all on its full breakdown.
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- Organic cotton/viscose with proprietary waterproof coating (unspecified)
- Undisclosed waterproof coating chemistry. Knix does not publicly identify the waterproof polymer or treatment…
3 hazards checked on this product, all on its full breakdown.
Find an alternative on Amazon
- Absorbent gusset with water-resistant coating, composition unspecified
- PFAS. Unspecified coating on absorbent gusset is typical vector for PFAS in period underwear; brand silence…
5 hazards checked on this product, all on its full breakdown.
Find an alternative on Amazon
- Absorbent textile blend with waterproof backing coating, composition unspecified
- Azo dyes in textiles. Conventional cotton-blend fabrics may use azo dyes, which can break down into aromatic…
5 hazards checked on this product, all on its full breakdown.
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- Synthetic blend with unspecified waterproof/leakproof coating
- PFAS. Brand silence on coating chemistry and Poor PFAS grade (25/100) suggest unconfirmed fluorinated…
3 hazards checked on this product, all on its full breakdown.
Find an alternative on Amazon
- Fabric with waterproof/leak-resistant coating, unspecified
- PFAS. Knix's PFAS safety score is 25/100, indicating high risk of fluorinated polymers or water-repellent…
4 hazards checked on this product, all on its full breakdown.
Find an alternative on AmazonWhat to buy instead Good or better, in the categories Knix sells
- organic cotton, waterproof backing layer
- A third party reports verifying it as PFAS-free
- Coating degradation and microparticle shedding
2 hazards checked on this product, all on its full breakdown.
- organic cotton blend, water-resistant gusset
- The brand calls it PFAS-free, which we have not verified
- Microplastic shedding from water-resistant barrier
- Organic cotton, wood pulp fiber
- The brand calls it PFAS-free, which we have not verified
- Azo dyes and synthetic dyes
2 hazards checked on this product, all on its full breakdown.
Knix and PFAS, common questions
- Does Knix have PFAS?
- Knix averages 25 out of 100 on PFAS Authority's PFAS and toxin screen across the 8 Knix products graded as of October 2026, and none of them reach its 70 point pass mark. Grades are model-based estimates built from published materials, ingredients and disclosures, not lab tests. Knix settled a class action over its marketing for $1.4 million and agreed to remove references to its products being PFAS free from its website.
- Is Knix non-toxic?
- No Knix product we graded reaches Good. The best of them is Knix SuperPlus Leakproof No- Show High Rise Underwear at 25/100.
- Which Knix products should I avoid?
- The lowest-graded Knix products we have scored are Knix Leakproof Ultra Thin High Rise Brief, Knix Heavy Flow & Bladder Leak Protection Underwear Superplus Leakproof No-Show High Rise, Knix Heavy Flow & Bladder Leak Protection Underwear. Each one links to the evidence behind its grade.
Every grade uses the same public rubric. How grades work →