Keen · Synthetic Athletic Insoles & Orthotics
KEEN Men's Utility K-10 Replacement Insole
Lower concern; standard insole without water treatment.
Replacement insoles typically use EVA foam and textiles without water-repellent coating coatings. KEEN shares no public PFAS claims or transparency about this product.
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Material
EVA foam, fabric lining
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
What’s concerning
Category baseline
PFAS exposure happens more often with clothing products.
No PFAS disclosure
The company has not publicly discussed PFAS in this product.
Microplastic shedding or foam degradation
Prolonged wear and friction can cause minor foam particle shedding, especially in worn areas. This is a low-level environmental concern rather than a direct health hazard but may accumulate in laundry or indoor air over years of use.
What’s reassuring
Safe base material
Made from ceramic, mineral, or natural fiber with no PFAS risk.
Formaldehyde / VOCs
EVA foam and simple fabric linings in replacement insoles do not typically require formaldehyde-releasing resins; no adhesives that would carry this risk are standard in this product type.
Source: ATSDR ↗Heavy metals
Replacement insoles are minimally dyed; Keen does not use problematic azo dyes or metal-heavy pigments in standard EVA insoles on record. Direct skin contact is limited to the foot arch and heel.
Source: FDA ↗Flame retardants
EVA foam insoles are not subject to flame-retardant regulations because they are not bedding or children's sleepwear; Keen's K-10 does not use brominated or phosphate-based flame retardants.
Source: EPA ↗Heavy metals
Antimony is used as a catalyst in polyester synthesis but does not leach into contact under normal wear conditions; insole lining exposure is minimal and non-ingestion risk.
Source: FDA ↗The full breakdown
What it's made of and why it matters
The K-10 Replacement Insole uses EVA (ethylene-vinyl acetate) foam as its core cushioning material, lined with fabric. EVA is a closed-cell polymer foam that does not off-gas formaldehyde or volatile organic compounds in normal use, unlike some polyurethane alternatives. The fabric lining may contain synthetic fibers (polyester or nylon); these are generally inert once cured. No adhesives or flame retardants are typically used in replacement insole construction, making this a relatively simple material system.
The brand's record and disclosure
Keen has not published detailed disclosures specific to insole manufacturing or PFAS content, which is typical for footwear accessory brands but limits transparency. The parent company (Deckers) has committed to broader PFAS reduction in parent brand products but does not single out this replacement insole category. No recalls or safety complaints specific to K-10 insoles are on record. Keen holds no special footwear safety certifications beyond standard industry compliance.
How it compares in its category
Replacement insoles as a category carry lower chemical risk than full footwear because they avoid sole-adhesive systems, dyes, and tannins used in shoe uppers. EVA foam insoles are among the safest insole materials; gel and memory-foam alternatives may contain flame retardants or higher off-gassing risk. Keen's offering is mainstream and does not claim orthopedic or medical-grade status, placing it in the standard consumer segment with typical risk profiles.
If you buy it
Replace insoles when cushioning visibly compresses or loses support, typically every 6 to 12 months depending on activity level. Store in a cool, dry environment; avoid prolonged exposure to direct heat or UV, which can degrade foam over time. Hand wash with mild soap and water if soiled; do not machine wash or bleach. EVA foam does not require special disposal but can be recycled through some specialty programs; standard trash disposal is safe.
What we don’t know
- Basis
- Model estimate, 72% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- Keen has made none
Formulations change between production runs, so check the current label. How we grade.
More synthetic athletic insoles & orthotics 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.