REI Co-op · Waterproof Outdoor Gear Storage Bags
REI Co-op Tarn 12 Pack
water-repellent coating treatment likely; PFAS status undisclosed by REI.
REI Co-op Tarn 12 Pack is a technical daypack likely treated with water-repellent coating. REI won't publicly confirm PFAS-free status or reveal treatment chemistry.
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Material
nylon/polyester blend with water-repellent coating water-resistant treatment
Lab data
No public lab test
What REI Co-op Tarn 12 Pack is made of, ingredients and materials
The Tarn 12 Pack is a nylon and polyester blend outerwear item treated with a water-repellent coating (water-repellent coating) finish. water-repellent coating treatments historically rely on PFAS "forever chemicals" (PFAS) to repel water and oil, though some manufacturers have shifted to fluorine-free alternatives. REI Co-op has not disclosed which water-repellent coating chemistry this product uses, leaving PFAS content ambiguous. The nylon and polyester themselves are stable synthetic fibers with low inherent toxicity when intact.
What’s concerning
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.
Waterproof / stain-resistant treatment
Water-repellent coating treatments have historically used PFAS.
PFAS
Standard nylon/polyester outdoor apparel relies heavily on PFAS-based water repellents. REI Co-op's silence on whether this product uses fluorine-free water-repellent coating makes PFAS presence probable without independent lab confirmation.
Source, ATSDR ↗Formaldehyde / VOCs
Nylon and polyester blends may contain trace formaldehyde-releasing resins used in wrinkle resistance or fabric stiffening. REI Co-op does not disclose finishing chemistry; levels, if present, are typically low in finished garments after washing.
Source, ATSDR ↗Coating degradation and microfiber shedding
Water-repellent coating coatings degrade over time and washing, potentially releasing microfibers and treatment residues. This is a documented issue across the outdoor apparel category rather than unique to REI Co-op, but relevant to lifetime product safety.
What’s reassuring
Azo dyes
No established recalls or public reports of restricted azo dyes in REI Co-op apparel. Nylon and polyester apparel typically uses regulated dyes in mainstream production, though formal third-party certification (e.g., GOTS, OEKO-TEX) is not documented for this product.
Antimony in polyester fiber
Antimony trioxide is a common polyester catalyst. Exposure risk from wearing finished garments is considered minimal by standard toxicology assessments, and no specific issues have been documented for REI Co-op products.
The full breakdown
The brand's record and disclosure
REI Co-op has made limited public commitments to eliminating PFAS from apparel and gear. Unlike some competitors (e.g., Patagonia's public PFAS reduction roadmap), REI has not issued specific transparency on water-repellent coating chemistry in their house brand. No major recalls or documented chemical contamination issues have been reported for REI Co-op apparel. The brand's silence on this issue is the primary concern rather than evidence of active harm.
How it compares in its category
Most conventional nylon and polyester outdoor apparel relies on PFAS-based water-repellent coating treatments, making the Tarn 12 Pack typical rather than exceptional. Some brands now offer fluorine-free water-repellent coating alternatives, though performance trade-offs are common. REI Co-op's lack of transparency places it squarely in the middle of the market; without product-level disclosure, consumers cannot differentiate this from competitors on water-repellent coating chemistry alone.
If you buy it
Minimize skin contact with wet product immediately after purchase, as fresh water-repellent coating finishes may shed excess treatment. Wash before first wear to reduce loose surface residues. Follow care instructions precisely, avoid high-heat drying and excessive detergent, which can degrade the coating and potentially mobilize residual chemicals. Replace when water repellency visibly fails (beading stops) rather than rewashing repeatedly to maintain the treatment.
What we don’t know
- Basis
- Model estimate, 45% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- REI Co-op has made a specific claim
Formulations change between production runs, so check the current label. How we grade.
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More waterproof outdoor gear storage bags 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.