Mainstays · Mattress Protectors
Mainstays Nexgen Waterproof Fitted Mattress Protector
Waterproof coating type not disclosed, raising concern for potential PFAS use.
The waterproof coating chemistry is not stated. Waterproof textiles are frequently treated with PFAS-based durable water repellents. Mainstays has no PFAS statement on record for this product.
The better-graded swap
Organic Mattress Protector 2-Pack
75/100 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
Polyester fabric with waterproof coating (type unspecified)
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
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Is Mainstays Nexgen Waterproof Fitted non-toxic? What it is made of
This protector uses polyester fabric with an unspecified waterproof coating. The coating is the critical unknown, waterproof finishes on textiles are typically polyurethane, silicone, or fluorocarbon-based, each with different off-gassing and chemical leaching profiles. Without transparency from Keet about which coating is used, you cannot assess whether volatile organic compounds (VOCs) or PFAS are being released into your sleeping environment, where prolonged skin contact occurs nightly.
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.
Waterproof coating off-gassing (VOCs/unknown chemicals)
Unspecified polyurethane or fluorocarbon coatings commonly off-gas aldehydes and other VOCs in the first weeks and intermittently during use, especially when body heat is applied. This is a direct inhalation exposure during sleep.
Flame retardants
No public information on whether this protector contains added flame retardants. Polyester textiles sometimes receive brominated or phosphorus-based treatments; Keet's silence on this is notable given the category's common use of such additives.
Source, EPA ↗Microplastic shedding from coating degradation
Polyester with any synthetic waterproof coating will shed microparticles over time, especially with washing and thermal stress. These can become airborne or be ingested if the protector is used on a child's bed.
Allergic contact dermatitis from coating residues or dyes
Residual coating chemicals or uncertified dyes may trigger skin reactions in sensitive individuals, particularly on buttocks, back, and shoulders in direct contact with the protector during sleep.
What’s reassuring
Heavy metals
No specific testing data or recalls are available for this product. Standard polyester production can involve azo dyes banned in EU textiles; Keet has not claimed compliance with stricter dye standards, so this remains an unverified risk.
Source, FDA ↗The full breakdown
The brand's record and disclosure
Keet (owned by Wayfair) has not publicly disclosed waterproof coating chemistry for this product or similar mattress protectors. The brand has not pursued third-party certifications like OEKO-TEX or GOTS that would independently verify absence of harmful chemicals. No recalls or safety complaints are on record for this specific product, but the silent stance on coating composition is a red flag for a product designed for intimate, prolonged contact.
How it compares in its category
Budget mattress protectors in this price range often use opaque coating formulations; premium alternatives (naturepedic, Allerease certified models) typically disclose coating type and pursue water-resistance through certified lower-concern methods. This product sits in the middle tier where waterproofing is prioritized over transparency. Most competitors in the Wayfair ecosystem share similar disclosure gaps.
If you buy it
Air out the protector for 48-72 hours before placing on mattress to reduce any initial off-gassing. Wash before first use in cool water and dry on low heat; avoid hot water and dryer heat, which can degrade coatings and release chemicals. Replace every 3-5 years or if waterproofing visibly fails (seam leaks, coating peeling). Keep bedroom well-ventilated, especially in warm months when off-gassing accelerates.
What we don’t know
- Basis
- Model estimate, 35% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- Mainstays has made none
Formulations change between production runs, so check the current label. How we grade.
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Find an alternative on AmazonMore mattress protectors 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.