PFAS score
Knot Sisters · Sports Bras
knotWTR Women's Sports Bra
No evidence of PFAS treatment; lower concern for basic sports bra.
Knot Sisters does not publicly disclose PFAS or water-repellent coating treatments for this bra. Base polyester/nylon fabrics carry lower PFAS risk than water-repellent sportswear.
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Material
polyester/nylon blend athletic fabric
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
Category baseline
clothing is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
Safe base material
Made from a material with no inherent PFAS use (ceramic, mineral, or natural fiber).
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 72% confidence. It is not a lab result.
No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.
The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.
Formulations and coatings change between production runs. Always check the current label before buying.
More sports bras grades
How we score: every product runs through the same public 0–100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.