Sorel Caribou Horizon GTX Women's
Winter boot with Gore-Tex; PFAS details not publicly disclosed.
Sorel Caribou Horizon GTX uses Gore-Tex for waterproofing, which commonly contains PFAS. No public PFAS disclosure from brand or third-party verification available.
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Material
Leather, rubber sole, Gore-Tex membrane
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
What Sorel Caribou Horizon GTX Women's is made of, ingredients and materials
The Caribou Horizon GTX uses full-grain leather uppers, a rubber sole, and a Gore-Tex waterproof-breathable membrane sandwiched into the boot structure. Leather itself is relatively inert once tanned, but the Gore-Tex membrane is the critical concern here, Gore-Tex is a Teflon-type coating (polytetrafluoroethylene) product whose water-repellency relies on fluorochemical treatments. The rubber sole presents low acute hazard but may off-gas low levels of volatile compounds during the first weeks of use, which is normal. Leather tanning chemicals (chromium salts or vegetable tannins, depending on process) are bonded into the material and not typically released during normal wear.
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.
Fluorochemical water repellents (Gore-Tex membrane)
Gore-Tex's Teflon-type coating base and fluorosurfactant treatments are confirmed PFAS-containing materials. Water, sweat, and wear can gradually mobilize these compounds; the membrane itself does not off-gas significantly but contact with skin perspiration and eventual disposal are exposure routes. Sorel has not disclosed PFAS levels or alternatives for this model.
Formaldehyde / VOCs
Leather finishing processes sometimes use formaldehyde-based resins for water resistance or color stability in the upper. Full-grain leather with vegetable tanning is lower risk; chrome-tanned leather finished with synthetic resins carries higher residual formaldehyde. Public tanning data for this specific Sorel batch is not disclosed; prolonged skin contact during wear could pose low-level exposu
Source, ATSDR ↗Rubber sole off-gassing (volatile organic compounds)
Synthetic rubber soles in new boots commonly emit low levels of volatile compounds (mercaptans, sulfur-containing molecules) during the first 4-8 weeks. This is temporary and decreases sharply with ventilation and wear. Not a health hazard at typical indoor exposure levels but may produce odor.
Azo dyes in leather or textile linings
Leather and fabric components may use azo dyes for coloring, some of which can release aromatic amines under sweat or friction. No recalls have been reported for Sorel boots on this issue. Vegetable-tanned leather is lower risk; chrome-tanned with synthetic dyes carries higher possible exposure.
What’s reassuring
Adhesive off-gassing (Gore-Tex bonding)
The adhesive layer bonding Gore-Tex to the boot structure typically uses polyurethane-based systems with minimal off-gassing once cured, which occurs before retail. No specific hazard data for this product line.
The full breakdown
The brand's record and disclosure
Sorel (owned by Columbia Sportswear) does not publicly disclose PFAS use, concentration, or phase-out timelines for waterproof boot lines as of available public records. The company has made general sustainability commitments but has not been transparent about per-fluorinated compound use in technical footwear. Sorel has no major product recalls tied to textile chemical contamination in recent years. The silence on PFAS specifically is notable given that Gore-Tex licensing is widespread in their winter boots.
How it compares in its category
Winter boots with Gore-Tex membranes across all major brands (Salomon, Merrell, The North Face, Keen) carry the same PFAS exposure pathway via the membrane itself. Boots using non-fluorinated waterproofing alternatives (eVent, PrimaLoft) are available but less common at this price point and may trade waterproof durability for chemical safety. The Caribou Horizon is mid-to-premium tier; comparable leather boots without Gore-Tex would have lower concern for PFAS but would sacrifice packability and breathability in wet conditions. Sorel's disclosure stance is less transparent than brands like Patagonia, which actively communicate PFAS strategies.
If you buy it
Condition the leather within the first month and annually thereafter with a wax or oil-based product not linked to PFAS to maintain the outer barrier and reduce reliance on internal Gore-Tex alone. Avoid machine washing or sustained heat (above 40C/104F) which can degrade the Gore-Tex adhesive bond; hand clean with cool water and mild soap. Store in a cool, dry place during off-season to extend Gore-Tex lifespan. Plan to re-waterproof the boot's upper exterior every 12-18 months of regular use; the Gore-Tex membrane is designed to last the boot's life but external treatments degrade faster.
What we don’t know
- Basis
- Model estimate, 52% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- SOREL has made none
Formulations change between production runs, so check the current label. How we grade.
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4 hazards checked on this product. See all of them.
More waterproof boots 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.