SealLine · Waterproof Bags & Luggage
SealLine Discovery Dry Bag
No PFAS disclosure; waterproof coating composition unclear.
This dry bag has urethane-coated nylon but provides no information on PFAS or water-repellent coating treatment chemicals. Waterproof coatings often contain PFAS, and the lack of transparency is problematic.
The better-graded swap
Salomon
Salomon Extended Totebag
85/100 safety
Same rubric that flunked this product. The swap earned Excellent.
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Urethane-coated nylon fabric with waterproof treatment
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
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.
Coating leaching and chemical migration
Urethane coatings can release plasticizers, softeners, or unreacted isocyanate residues, particularly if the bag contacts acidic foods, alcohol, or warm liquids for extended periods. No specific migration data for SealLine products is publicly available.
Degradation of waterproof integrity over time
Urethane and nylon are both prone to UV and heat degradation, especially in outdoor storage. As the coating breaks down, micro-cracks may expose the nylon base, compromising waterproofing and potentially increasing exposure to any coating residues.
Microplastic generation from fabric abrasion
Nylon fabrics shed microfibers when abraded, particularly at stress points like zippers and seams. If the coating delaminates or wears, abrasion release increases; these fibers can contaminate stored food or water.
PFAS
Industry-wide, most synthetic waterproof coatings historically relied on PFAS-based Teflon-family coating; the shift to non-fluorinated alternatives remains ongoing. SealLine's silence on this compound means PFAS cannot be ruled out.
Source, ATSDR ↗Odor and VOC emissions from coating off-gassing
New urethane-coated products often emit volatile organic compounds and solvent odors. SealLine does not characterize off-gassing duration or chemical composition, so cumulative indoor air exposure is unknown.
The full breakdown
What it's made of and why it matters
The SealLine Discovery uses urethane-coated nylon fabric as its core material. Urethane coatings provide water resistance through a polymer layer applied to fabric; the waterproofing treatment itself is not specified by the manufacturer, creating uncertainty about whether it relies on PFAS-based compounds (Teflon-family coating) or alternative chemistries. Nylon itself is stable under normal use, but the durability of the coating and any migration of coating components during prolonged contact with food, skin, or liquids stored inside is not independently documented.
The brand's record and disclosure
SealLine does not publicly disclose the chemical composition of its waterproof treatments or provide PFAS-free certifications on this product line. The company has not published transparency reports or responses to PFAS safety inquiries in mainstream consumer or environmental databases. Without explicit commitment to PFAS avoidance or third-party testing, the coating formulation remains a black box from a safety standpoint.
How it compares in its category
Most waterproof bags in the consumer market rely either on PFAS-containing water-repellent coating (water-repellent coating) treatments, polyurethane or PVC coatings, or wax-based alternatives. SealLine's urethane-coated approach is mid-range in transparency, better than unlabeled discount brands, but behind competitors (such as some outdoor brands using PFAS-free certifications or silicone-based coatings). The lack of any third-party certification places it in the 'trust the brand' category, which SealLine does not fully justify with disclosure.
If you buy it
Avoid prolonged storage of food, especially fatty or acidic items, inside the bag, as urethane coatings can leach plasticizers under chemical stress. Store the bag in a cool, dry place to slow any degradation of the coating; do not leave it in direct sunlight or heat for extended periods, as urethane degrades faster in those conditions. Inspect seams and the coating annually for cracks, peeling, or discoloration; replace the bag if the coating shows visible deterioration. Do not machine wash; hand rinse with plain water only to minimize coating wear.
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
- SealLine has made none
Formulations change between production runs, so check the current label. How we grade.
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VOC off-gassing from dyes and finishes
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⚠Brand says nothing about PFAS
More waterproof bags & luggage 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.