I Emailed Knix About PFAS. They Sent me a script. Here's what they left out.
CONSUMER ACTION - A PFAS WATCH
A $1.4 million settlement, a court order to stop calling their products PFAS-free, and a customer support email that reads like nothing happened.
Modern Garment District April 2025 Consumer Action
I have been buying Knix leakproof underwear for years. Like a lot of people, I chose them because they marketed themselves as a safer, more sustainable alternative. So when I started doing serious research into PFAS in apparel, the kind of research that led me to publish 11 free compliance documents at Modern Garment District, I did what any informed consumer should do. I emailed them directly.
What I got back was polished, reassuring, and carefully constructed to tell me almost nothing useful. What it did not mention was the $1.4 million federal class action settlement Knix entered into over the exact products I asked about.
What Knix Told Me
Their response hit every greenwashing beat. PFAS are "not a part of the design." They use an "industry-leading lab." Testing shows results "not detected" at limits of 0.01 to 1 parts per million. They present themselves as transparency leaders who became "a target" for speaking openly.
FROM KNIX CUSTOMER SUPPORT
"PFAS are not a part of the design of Knix's leakproof underwear, meaning we only select fabrics where PFAS are not intentionally added... In these tests you will see that PFAS was not detected in the tested products at the testing limits of 0.01-1 parts per million."
Every one of those phrases is doing specific legal and rhetorical work.
"Not intentionally added" is not the same as not present. A detection limit of 1 ppm (1,000 parts per billion) is not a health safety standard, it is a measurement threshold.
And sharing "samples" of test results is not the same as sharing all results.
"Not intentionally added is not the same as not present. A detection limit is not a safety guarantee."
What Knix Didn't Mention
Knix settled a federal class action lawsuit, Spencer, et al. v. Knix Wear Inc., Case No. 1:23-cv-07823-JLR, for $1.4 million. The lawsuit alleged that Knix marketed its leakproof products as free from PFAS and toxic chemicals when independent testing detected these substances in their products.
Case Spencer et al. v. Knix Wear Inc.
Case number1:23-cv-07823-JLR
Settlement amount $1.4 million (+ up to $600K additional)
Products covered Knix leakproof underwear, Jan 2020 – Dec 2022
Key term Knix agreed to remove "PFAS-free," "toxic chemical-free," and "fluorine-free" from all marketing
Claims deadline March 11, 2024 (now closed)
Read that key term again: as part of the settlement, Knix agreed to stop calling their products PFAS-free, toxic chemical-free, or fluorine-free. A court found that language to be misleading enough to require its removal. Yet the email they sent me in April 2026 uses functionally identical reassurances, no mention of the settlement, no acknowledgment that this language was found to be deceptive.
The Detection Limit Problem
Knix's response cites a detection range of 0.01 to 1 ppm. That upper end, 1 ppm, or 1,000 ppb, is not a reassuring number when you understand what it means.
For context, EPA drinking water limits for individual PFAS compounds are measured in parts per trillion.
A fabric test that clears a 1 ppm screen can still contain meaningful concentrations of concerning compounds. The meaningful question is not whether PFAS were detected above a given threshold, it is what the total fluorine result was, which is a far more sensitive and honest indicator.
What I Asked Them and What You Should Ask Too
I sent Knix a follow-up email identifying myself as the publisher of Modern Garment District and requesting specific answers.
Here is what every consumer asking these brands about PFAS should demand:
THE FOUR QUESTIONS TO ASK
What was the total fluorine (TOF) result, not just whether individual PFAS cleared your detection limit?
What was the specific detection limit used for each individual PFAS compound tested?
Are the full, unredacted third-party lab reports available — not blog summaries?
Were finished products tested, or only raw fabrics? Both?
The Thinx Parallel
Knix is not alone.
Thinx, the other major name in leakproof underwear, settled a separate PFAS class action for up to $5 million after independent testing found fluorine levels in the thousands of parts per million in their products, levels consistent with intentional addition. Both companies used the same rhetorical playbook: "not intentionally added," "not detected at our testing limits," and positioning themselves as transparency advocates while settling federal lawsuits.
The pattern is not a coincidence.
It is a script.
What You Can Do
CONSUMER ACTION STEPS
Email the brands you buy from. Use the four questions above. Document the response you receive.
File a complaint with the FTC (ftc.gov/complaint) if you believe a company's post-settlement communications still mislead consumers.
File with your state Attorney General's consumer protection office, many states have active PFAS enforcement programs.
Share your experience publicly. Companies respond differently when they know a customer has an audience and a paper trail.
Access free PFAS compliance documentation at moderngarmentdist.gumroad.com 12 reference documents, all free. Regular updates.
Join the ModernGarmentDistrict.com for the latest news and updates on PFAS Intel.
I will update this post when and if Knix responds to my follow-up. If you have had similar experiences with Knix or other leakproof underwear brands, I want to hear from you. Comment below or email me at: PFAS@ModernGarmentDistrict.com
Gina Vincenza Van Epps
ABOUT THE AUTHOR
Gina Vincenza Van Epps is an Emmy Award-winning celebrity seamstress, costume designer, and garment industry advocate based in Orlando, Florida. She is the founder and author of the Modern Garment District Model — conceived as a disruptive alternative to conventional apparel production and now fast becoming the new PFAS-compliant industry standard, built on Proof of Concept production principles. As a former managing partner of a green deconstruction, demolition, and salvage company, she brings firsthand professional experience in hazardous materials handling and environmental remediation — knowledge that directly informs her work exposing PFAS in the apparel supply chain. She publishes free PFAS compliance documentation and consumer resources through Modern Garment District, giving industry and consumers alike the tools to demand real transparency. With over 70 celebrity clients, 15 years of advocacy for ethical American manufacturing, and a background spanning fashion, environmental compliance, and entertainment, Gina is an active PFAS whistleblower whose cross-disciplinary expertise is reshaping how the garment industry is held accountable.
PFAS Consumer Action, Knix Leakproof Underwear, Forever Chemicals, Greenwashing
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