nectar mattress encasement super king size new
Avoid until the brand discloses waterproof treatment chemistry.
This polyester encasement is marketed as waterproof but the brand does not disclose what chemicals achieve that water resistance. Mattress protectors frequently rely on PFAS-based water-repellent coating treatments.
The better-graded swap
Nectar
Nectar MAX Set Mattress
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/polyurethane encasement with water-resistant 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.
Water-resistant chemical composition (undisclosed)
Nectar has not disclosed the water-repellent coating chemistry used on this encasement. Industry standard for polyester mattress protectors historically defaults to PFAS-based finishes unless explicitly stated otherwise. This product carries the categorical risk of PFAS exposure (graded separately at 30/100) without transparency to support alternatives.
Polyurethane backing degradation
Polyurethane foam or film backing can break down over 3-5 years, especially if exposed to heat, moisture, or UV. Degradation may release small polymer particles and can compromise water resistance. No manufacturer data on lifespan or degradation products available for this model.
Microplastics
Polyester encasements shed microfibers during washing and use, particularly if the surface treatment is damaged. This is inherent to the material class but not specific to Nectar; gentle washing and air drying minimize release. The undisclosed finish may accelerate or slow shedding depending on its chemistry.
Source, EPA ↗Flame retardants
If the underlying mattress uses older brominated or chlorinated flame retardants, the encasement may not fully isolate them but can reduce dust and vapor contact. This is a benefit of the barrier, not a hazard from the encasement itself, but effectiveness depends on fit and seal integrity.
Source, EPA ↗What’s reassuring
Adhesives and seam treatments
Polyurethane-based adhesives used in seam bonding are not typically a major hazard if fully cured before purchase, but Nectar does not disclose cure time or adhesive type. No recalls or complaints specific to seam off-gassing for this product are on record.
The full breakdown
What it's made of and why it matters
This Nectar encasement is polyester fabric with polyurethane backing and a water-resistant treatment applied to the surface. The water-resistant layer is the critical unknown, Nectar has not publicly disclosed whether this uses PFAS-based water-repellent coating (water-repellent coating) or alternative chemistries. Polyester itself is stable and non-toxic when undamaged, but the proprietary finish on this product is where chemical risk concentrates. The backing and seams may also contain adhesives or coatings not itemized in marketing materials.
The brand's record and disclosure
Nectar Sleep does not publish material safety data sheets, PFAS testing results, or certifications (OEKO-TEX, GOTS, etc.) for this encasement. The brand has not responded publicly to growing questions about PFAS in mattress protectors, and their website does not list waterproof treatment ingredients. This silence is a red flag in a product category where PFAS-free alternatives are increasingly marketed. Without third-party certification or direct disclosure, buyers cannot verify chemical safety.
How it compares in its category
Many competitors (Saatva, Helix, Casper) now explicitly market PFAS-free encasements or carry OEKO-TEX Standard 100 certification. Budget alternatives often use the same polyester-polyurethane design but may carry fewer hazards if they use certified treatments. Nectar's silence puts it below the transparency standard of the mainstream market; premium brands have largely moved to non-fluorinated water-repellent coating or mechanical water resistance. Price point does not reflect any documented safety advantage.
If you buy it
Wash the encasement once before use to remove any loose finish; use warm (not hot) water and air dry to avoid degrading the backing. Do not expose to prolonged heat (direct sunlight, steam cleaning, or dryers above 130F) as polyurethane can soften and shed microplastics. Inspect seams and backing annually for peeling or cracking; replace if waterproof layer visibly deteriorates. Keep away from prolonged contact with mattress chemicals (flame retardants) by ensuring proper mattress ventilation underneath.
What we don’t know
- Basis
- Model estimate, 42% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- Nectar has made none
Formulations change between production runs, so check the current label. How we grade.
Better-graded alternatives in Mattress Protectors
Helix
Premium Mattress Topper
polyurethane foam, polyester cover
Volatile Organic Compounds (VOC) off-gassing from polyurethane foam
Limited concern
Polyester cover degradation and microfiber shedding
Limited concern
Polyurethane foam degradation and chemical leaching with age
Limited concern
Water-resistant coating composition (undisclosed)
Limited concern
Lower PFAS risk, though contact Helix directly for water-resistant coating details they don't disclose.
⚠Starting grade for this product type
Casper
Sleep Comfy Mattress Topper
Polyurethane foam, cotton/polyester blend cover
Volatile Organic Compound (VOC) off-gassing
Limited concern
Polyurethane foam degradation and particle shedding
Limited concern
Dust mite and mold colonization
Limited concern
Lower PFAS concern for standard foam topper with no known water-repellent coating or stain treatment, unless you need verified PFAS-free assurance.
⚠Starting grade for this product type
Casper
Sleep Essential Mattress Topper
polyfoam/polyurethane foam topper
Volatile organic compound (VOC) off-gassing
Limited concern
Microplastic shedding
High concern
Flame retardants
Limited concern
Moisture and mold accumulation in use
Limited concern
Lower risk than coated fabrics, but contact Casper to confirm no finishing chemicals.
⚠Starting grade for this product type
More 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.