Is Thorlo PFAS-free?
Across 15 graded products, Thorlo averages D (65/100). On disclosure, the brand says nothing publicly about PFAS. None of its products grade C or better yet. Grades are model-based estimates, not lab results.
Graded and flagged D and F, we’d swap these
Thorlo
s Men's KX Max Cushion Hiking Crew Socks
Merino wool blend, polyester, nylon, elastane
Lower PFAS concern; standard hiking sock with no known water-resistant treatment.
⚠Risky category by default
Thorlo
Boy Scout Thorlos Low Cut Hiking Socks
Acrylic, nylon, polyester blend (standard athletic sock fibers)
Lower PFAS concern, standard sock construction unlikely to require PFAS, but brand makes no explicit commitment.
⚠Risky category by default
Thorlo
s Men's Hiking Crew Socks
merino wool blend, acrylic, nylon (standard textile)
Lower-concern baseline; standard hiking socks with no known PFAS triggers, though no explicit commitment from brand.
⚠Risky category by default
Thorlo
s Thorlo Men's Light Hiking Crew Socks
Merino wool blend, nylon, polyester
Lower PFAS concern; standard hiking sock with no waterproofing or water-repellent coating treatment.
⚠Risky category by default
Thorlo
s Walking Crew 3-Pair Pack
Merino wool blend, acrylic, nylon
Lower concern; traditional sock materials with no known PFAS triggers, but brand silence limits assurance.
⚠Risky category by default
Thorlo
s Ultra-Light Hiking Crew Socks Men's
Acrylic blend (nylon/acrylic/polyester) with cushioning
Lower PFAS concern for standard hiking socks, no water-repellent treatment typical in this category.
⚠Risky category by default
Thorlo
s Men's Light Hiker Crew 3-Pair Pack
Merino wool blend, acrylic, nylon, polyester
Lower concern; conventional sock without water-repellent marketing, but no brand transparency on PFAS.
⚠Risky category by default
Thorlo
Men's Moderate Cushion Ankle Hiking Socks
Merino wool blend (primary); synthetic blend cushioning
Lower concern, natural fiber blend without water repellency claims typical of hiking socks.
⚠Risky category by default
Thorlo
s Men's Running Crew 3-Pair Pack
Acrylic blend crew socks (synthetic fibers)
Lower concern, standard athletic socks with no known PFAS triggers, but brand offers no transparency.
⚠Risky category by default
Thorlo
Unisex Maximum Cushion Ankle Running Socks (6-Pack)
Acrylic, cotton, nylon blend with cushioning
Lower PFAS concern; basic athletic sock with no disclosed water/stain treatments.
⚠Risky category by default
Thorlo
s Running Crew
Merino wool blend / synthetic fibers (acrylic/nylon)
Lower concern, basic crew sock with no waterproofing or stain treatment signals, but no public PFAS commitment from brand.
⚠Risky category by default
Thorlo
s Running Rolltop 3-Pair Pack
Acrylic blend textile (no water-resistant coating disclosed)
Lower concern, basic socks with no water-repellent finish, but brand offers no PFAS transparency.
⚠Risky category by default
Thorlo
s Men's TRMX Max Cushion Trail Hiking Ankle Socks (3 Pair Pack
Merino wool blend, synthetic fiber
Lower PFAS concern; no evidence of intentional fluorochemical treatment, but brand discloses nothing.
⚠Risky category by default
Thorlo
s Men's Thorlo Running Mini Crew Socks
Acrylic, nylon, spandex blend (standard athletic socks, no special coatings noted)
Lower PFAS concern, plain athletic socks with no Teflon-family coating or water-repellent coating treatment apparent.
⚠Risky category by default
Thorlo
s Maximum Cushion Rolltop Tennis Socks (3-Pack)
Acrylic blend yarn (cushioned textile)
Lower-concern socks; no known PFAS triggers, but brand silence on treatment limits full assurance.
⚠Risky category by default
Every grade uses the same public rubric. How grades work →