Mountainsmith · Waterproof Outdoor Gear Storage Bags
Mountainsmith Divide EVO Daypack
Unknown water-repellent coating chemistry; no PFAS disclosure or testing data available.
Mountainsmith makes no public claims about PFAS or water-repellent coating treatment chemistry on this daypack. The nylon likely carries a water-repellent coating, but the manufacturer doesn't disclose its composition.
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Material
nylon ripstop with water-repellent coating treatment, specific chemistry unspecified
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
What Mountainsmith Divide EVO Daypack is made of, ingredients and materials
The Divide EVO uses nylon ripstop as its primary fabric, a lightweight, durable polymer mesh woven with reinforcing threads. The critical unknown is the water-repellent coating (water-repellent coating) finish applied to this nylon. water-repellent coating coatings historically relied on PFAS "forever chemicals" (PFAS) but have been shifting toward fluorine-free alternatives; Mountainsmith has not publicly specified which chemistry they use. Nylon itself is not inherently hazardous, but the applied treatment chemistry determines residual toxicity risk.
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
Mountainsmith does not disclose water-repellent coating chemistry. Nylon ripstop water repellents traditionally used PFOA, PFOS, or related fluorinated compounds; many brands have phased these out, but absence of disclosure means fluorine-free status cannot be assumed. Risk is greatest during initial use and washing.
Source, ATSDR ↗Microfiber shedding and degradation of water-repellent coating
What’s reassuring
Formaldehyde / VOCs
Nylon ripstop does not typically require formaldehyde-based dyes or wrinkle-resistant finishes. No evidence of such treatments in this product category; standard nylon processing avoids this hazard class.
Source, ATSDR ↗Azo dyes
The Divide EVO is marketed in solid earth tones (olive, charcoal, etc.). Nylon ripstop is not dependent on azo dyes for these colors, and no public concerns or recalls exist for Mountainsmith packs on this issue.
Antimony in polyester components
Primary material is nylon, not polyester. Seam tape, mesh liners, or webbing may contain polyester; Mountainsmith does not specify. Risk is low unless large secondary polyester content and poor antimony controls, which is uncommon in outdoor gear.
The full breakdown
The brand's record and disclosure
Mountainsmith does not publicly disclose water-repellent coating chemistry, PFAS testing data, or relevant certifications (such as OEKO-TEX or Bluesign) for the Divide EVO. The brand maintains no visible sustainability or chemical transparency statements on their website or product documentation. This silence is notable in a market where competitors increasingly volunteer fluorine-free water-repellent coating information; lack of disclosure does not confirm PFAS presence but indicates no proactive safety communication.
How it compares in its category
Most mid-range outdoor daypacks in this segment (REI Co-op, Arc'teryx, Patagonia) either publicly state fluorine-free water-repellent coating or carry third-party certifications. The Mountainsmith Divide EVO is competitively priced and functional but lags in chemical transparency relative to brands that disclose their water-repellent coating chemistry. Nylon ripstop durability is standard across the category; the differentiator here is the absence of reassurance about the treatment layer.
If you buy it
Wash the pack periodically with mild detergent and cool water to reduce buildup of residual chemicals and contaminants. Avoid high-heat drying or direct sun exposure for prolonged periods, as this can accelerate coating degradation and potential microfiber shedding. Do not machine wash in hot water or bleach, as these can compromise the water-repellent coating layer and increase leaching from any remaining treatment residues. Store in a cool, dry place away from direct heat or solvents. If you are PFAS-sensitive or pregnant, consider requesting water-repellent coating chemistry confirmation from Mountainsmith before purchase, or choose a brand with published fluorine-free documentation.
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
- Mountainsmith has made none
Formulations change between production runs, so check the current label. How we grade.
Better-graded alternatives in Waterproof Outdoor Gear Storage Bags
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Patagonia
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- The brand calls it PFAS-free, which we have not verified
- PFAS
4 hazards checked on this product. See all of them.
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.