Mainstays · Mattress Protectors
Mainstays Jersey Soft Fitted Mattress Cover Protector
Avoid until waterproof treatment is disclosed.
Waterproof mattress covers typically use water-repellent coating finishes with historical ties to PFAS chemistry. The brand provides no public disclosure of coating composition or PFAS status.
The better-graded swap
Sleepyhead
Sleepyhead 3 Copper-Infused Memory Foam Mattress Topper with Washable Cover
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
Jersey knit with waterproof coating (unspecified)
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
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Is Mainstays Jersey Soft Fitted Mattress non-toxic? What it is made of
This product combines a jersey knit top layer (soft cotton-blend fabric) with an unspecified waterproof coating on the underside. Jersey knit itself is a standard, low-risk material, but the waterproof treatment is the critical unknown, it could be polyurethane, acrylic, or fluorochemical-based (PFAS). Because Waterproof Inc. does not disclose the coating chemistry, you cannot assess whether it will leach chemicals into bedding, off-gas volatile organic compounds (VOCs), or degrade into microparticles over time.
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
The product is marketed with a waterproof barrier but no disclosure of the treatment agent. Industry reporting shows many budget waterproof mattress protectors from 2019-2023 still use legacy PFAS-based fluorochemical coatings; this product's poor PFAS grade (30/100) and silent brand stance suggest high likelihood of PFOA or other long-chain PFAS in the coating.
Source, ATSDR ↗Volatile organic compound (VOC) off-gassing from waterproof coating
Jersey-backed waterproof protectors can release formaldehyde-based resins or solvent residues during manufacturing and early use, especially if the coating is adhesive-based polyurethane. Off-gassing risk is highest in poorly ventilated bedrooms and with new, unwashed products.
Coating degradation and microparticle shedding
Polyurethane and acrylic waterproof coatings degrade over 2-5 years with moisture exposure, temperature cycling, and mechanical stress (body weight, washing). No information on coating durability or warranty suggests this product may shed plastic or rubber particles into bedding once degradation begins.
Contact dermatitis or allergic reaction from coating chemicals or residues
Undisclosed waterproof treatments may contain isocyanates, plasticizers, or antimicrobial agents that trigger skin irritation, especially in people with sensitive skin, eczema, or chemical sensitivities. Lack of hypoallergenic certification increases this risk.
What’s reassuring
Inadequate liquid barrier performance over time
No recalls or field reports of failure are on record, but waterproof mattress protectors with unknown coating formulations may lose water-repellency faster than tested alternatives, offering false protection and allowing moisture into the mattress.
The full breakdown
The brand's record and disclosure
Waterproof Inc. maintains silence on PFAS use and waterproof treatment chemistry, which is a significant red flag in a category where major competitors (Allerease, Bamboo Protection, Helix) now publish PFAS-free certifications or OEKO-TEX accreditation. No public recalls or safety controversies appear on record for this specific product, but the lack of transparency about a liquid-facing coating suggests either outdated formulations or unwillingness to disclose PFAS-containing treatments. Third-party certifications (GOTS, OEKO-TEX, STANDARD 100) are absent from available product information.
How it compares in its category
Budget mattress protectors in this price tier often use older polyurethane or acrylic waterproof technologies without PFAS disclosure. Premium alternatives (Saatva, Helix, Naturepedic) increasingly market PFAS-free polyurethane or silicone-based coatings and provide third-party testing results. This Mainstays product sits in the transparency gap, cheaper than certified options but offering no chemical accountability, making it riskier for households sensitive to VOCs, chemical off-gassing, or concerned about PFAS bioaccumulation.
If you buy it
Wash before first use in warm water to remove any loose coating residue or manufacturing chemicals. Avoid high heat (no hot water washing or high dryer temperatures), as waterproof coatings can degrade, shed microparticles, or release VOCs when heated. Check the coating every 6-12 months for peeling, cracking, or separation from the fabric; once degradation begins, replacement is advisable. Store in a cool, dry location and ensure the mattress itself can breathe (use on a slatted or permeable base) to minimize moisture pooling, which accelerates coating breakdown.
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.