Smartwool Review, Is Smartwool Non-Toxic?
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.
Across 11 graded products, Smartwool averages Good (61/100). On disclosure, the brand says nothing publicly about PFAS. None of its products grade Good or better yet. Grades are model-based estimates, not lab results.
Graded and flagged Poor and Bad, we’d swap these
Smartwool
Men's Mountaineer Classic Edition Maximum Cushion Crew Socks
Merino wool blend (primary natural fiber)
Lower PFAS concern. Natural wool fiber with no waterproofing treatment flagged. No explicit PFAS disclosure.
⚠Risky category by default
Smartwool
Men's Hike Full Cushion Crew Socks
Merino wool blend (merino wool, nylon, elastane)
Lower PFAS concern. Natural fiber socks unlikely to need water-repellent coating. Smartwool's lack of disclosure leaves room for uncertainty.
⚠Risky category by default
Smartwool
Men's Hike Classic Edition Full Cushion Crew Socks
Merino wool blend (primary fiber); no reported water-repellent coating (water-repellent coating) or stain treatment disclosed
Lower PFAS concern. Plain wool socks with no disclosed treatments, but verify fiber content if it matters.
⚠Risky category by default
Smartwool
4-Pack Everyday Athletic Crew Socks
merino wool blend (primary fiber)
Azo dyes (aniline-derived synthetic colorants)
Merino socks are dyed during manufacturing; textile dyehouses in some regions use azo…
Elastane (spandex) degradation and skin contact
Elastane fibers can degrade under heat, UV, or chlorine, releasing oligomers that may…
Durable-water-repellent (water-repellent coating) coating composition
Smartwool uses a water-repellent coating treatment on athletic socks to improve moisture…
Lower PFAS concern for basic merino socks, but Smartwool doesn't publicly disclose water-repellent coating chemistry.
⚠Risky category by default
Smartwool
Men's Hike Medium Crew Socks
Merino wool blend (primary), elastic, synthetic dyes
Azo dyes in synthetic fiber components
Smartwool does not publish azo dye test results or restricted substance lists for sock…
Microplastics
Elastane (spandex) in sock cuffs and arch support degrades with repeated washing and UV…
Lower PFAS concern for basic wool socks, but no transparency from Smartwool.
⚠Risky category by default
Smartwool
Men's Run Targeted Cushion Mid Crew Socks
Merino wool blend with synthetic nylon reinforcement
Lower concern. Natural fiber socks unlikely to contain PFAS.
⚠Risky category by default
Smartwool
Run Pattern Crew Socks 3-Pack
Merino wool blend, no water repellent finish
Lower concern. Merino wool socks with no waterproof coating.
⚠Risky category by default
Smartwool
Women's Run Targeted Cushion Low Ankle Socks
Merino wool blend, no specified water-repellent coating treatment
Lower concern. Merino wool socks without disclosed water repellent treatment.
⚠Risky category by default
Smartwool
Unisex Run Zero Cushion Crew Socks
Merino wool blend, no stated water-repellent treatment
Lower concern. Merino wool socks lack typical water-repellent coating coatings.
⚠Risky category by default
Smartwool
Men's Run Zero Cushion No Show Socks
Merino wool blend, no reported water-resistant treatment
Lower concern. Merino wool socks unlikely to contain intentional PFAS.
⚠Risky category by default
Smartwool
Men's Run Cold Weather Targeted Cushion Crew Socks
Merino wool with water-repellent coating finish
Merino wool is PFAS-risk material; water-repellent coating finish raises concern.
⚠Waterproof or stain-proof treatment
Every grade uses the same public rubric. How grades work →