HOKA · Running & Athletic Shoes
Hoka Women's Challenger 8
Skip until brand discloses waterproofing chemistry.
Hoka does not disclose PFAS or water-repellent coating treatment details for this running shoe. Standard textile running shoes often use PFAS-based water repellents, but absence of disclosure prevents confirmation.
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Textile upper with water-repellent treatment, synthetic sole
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
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What Hoka Women's Challenger 8 is made of, ingredients and materials
The Challenger 8 upper is synthetic textile (likely polyester or nylon blend) with an applied water-repellent finish; the sole is synthetic rubber or TPU. The water-repellent treatment is the critical unknown, Hoka has not disclosed whether it uses Teflon-type coating-based (legacy PFAS), fluorine-free, or other chemistry. Synthetic uppers are prone to off-gassing volatile organic compounds (VOCs) during manufacturing and early wear, particularly in warm or humid conditions. The sole material itself carries lower chemical concern than the upper treatment.
What’s concerning
Waterproof / stain-resistant treatment
Water-repellent coating treatments have historically used PFAS.
Category baseline
The starting point for this type of product, before anything specific to this product is counted.
No PFAS disclosure
No public statement from the brand about PFAS in this product.
PFAS
Hoka has not disclosed the chemistry of the water-repellent treatment applied to the synthetic upper. Standard industry practice for athletic footwear of this type historically relies on Teflon-type coating or related PFAS compounds; fluorine-free alternatives are available but not confirmed here. Wear and washing accelerate leaching into sweat and the environment.
Source, ATSDR ↗Volatile organic compounds (VOCs) off-gassing
Synthetic textile uppers and adhesives used in shoe assembly release VOCs during manufacturing and early wear. Off-gassing is most pronounced in the first weeks of use and in warm, humid conditions but is not typically acutely toxic at normal exposure levels; however, cumulative indoor exposure in poorly ventilated spaces may elevate inhalation risk.
Azo dyes in synthetic textiles
Synthetic fabrics in athletic footwear may be dyed with azo colorants, some of which can break down into aromatic amines under sweat or UV exposure. Hoka does not provide dyeing chemistry or restricted substance list (RSL) compliance data. Risk is generally low under normal wear but increases with perspiration contact and heat.
Antimony in polyester
If the synthetic upper is polyester (common in this category), antimony trioxide may be present as a catalyst residue in the polymer. Hoka does not disclose polyester sourcing or antimony testing. Migration risk is low in finished textile but increases with degradation, washing, and heat exposure over time.
Formaldehyde / VOCs
Water-resistant and durable-press finishes in synthetic uppers, as well as adhesives binding the sole, may contain or release formaldehyde. Hoka provides no third-party certification (OEKO-TEX, BLUESIGN) to rule this out. Exposure risk is typically low during wear but increases with moisture, perspiration, and warm storage conditions.
Source, ATSDR ↗How is this PFAS grade calculated?
The brand's record and disclosure
Hoka (owned by Deckers Brands) does not publicly disclose waterproofing chemistry for its athletic footwear. The brand has not published PFAS reduction commitments or third-party certifications (such as BLUESIGN or OEKO-TEX) for textile layers. No established recalls or safety controversies specific to the Challenger line are on public record. This silence on water-repellent treatment chemistry is the defining transparency gap.
How it compares in its category
Women's running shoes at this performance tier (Hoka competes with Nike, Brooks, ASICS, Salomon) routinely use water-repellent treatments without public disclosure of their chemistry. Some competitors (notably Allbirds, Patagonia-adjacent brands) now offer fluorine-free or PFAS-free certified options in the broader athletic footwear market, though mainstream performance brands lag. The Challenger 8's lack of transparency is typical for Hoka's category position, not an outlier; however, this does not reduce the hazard concern.
If you buy it
Wear shoes outdoors during break-in to allow initial VOC off-gassing before extended indoor use, especially in warm conditions. Avoid machine washing; hand-clean with mild soap and air dry away from heat sources to slow leaching of water-repellent coating. Replace the shoe when the water-repellent finish visibly degrades (beading loss on the upper) or after 300-500 miles, as coating breakdown can increase leachate concentration. Store in a well-ventilated space; do not store in sealed containers for extended periods.
What is not known about PFAS in this product?
- Basis
- Model estimate, 35% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- HOKA has made none
Formulations change between production runs, so check the current label. How we grade.
What are the PFAS-free alternatives to Hoka Women's Challenger 8?
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4 hazards checked on this product, all on its full breakdown.
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2 hazards checked on this product, all on its full breakdown.
Find an alternative on AmazonMore running & athletic shoes 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.