PFAS40/ 100Poor
Overall32/ 100Poor
Polar Elastic Nylon Watch Band

Polar · Water-Resistant Smart Rings & Bands

Polar Elastic Nylon Watch Band

Poor

Elastic nylon waterproofing details unknown, avoid if concerned.

Verdict · SkipElastic nylon band with unknown waterproofing chemistry poses uncertain PFAS risk; no major toxicity red flags reported, but water-resistant treatment details lack transparency.

Polar does not disclose PFAS or waterproofing chemistry for this band. Elastic nylon typically receives PFAS-containing water-repellent coating coatings.

The better-graded swap

Oura Smart Ring 4

Oura

Oura Smart Ring 4

85/100 safety

85Excellent

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

Elastic nylon with likely 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.

90/ 100
♾️

No PFAS disclosure

No public statement from the brand about PFAS in this product.

85/ 100
♾️

Waterproof / stain-resistant treatment

Water-repellent coating treatments have historically used PFAS.

65/ 100
♾️

PFAS

Elastic nylon watch bands require water-repellent coating (water-repellent coating) treatment to function; Polar does not disclose whether this uses legacy PFAS (PFOA/PFOS) or modern alternatives (GenX, PFBS). Industry practice has shifted toward fluorine-free or short-chain PFAS in recent years, but older stock or budget suppliers may still use older chemistry. Without material disclosure, assume moderate uncertaint

Source, ATSDR
70/ 100

Spandex/elastane degradation and sweat exposure

Elastic fibers in the band may break down over time with repeated sweat, heat, and UV exposure, potentially fragmenting or releasing monomers; however, body temperature and normal wear do not trigger significant spandex leaching. Risk is primarily durability-related rather than acute toxicity, but sensitive skin users should monitor for irritation.

70/ 100

What’s reassuring

💨

Formaldehyde / VOCs

Nylon textiles sometimes use formaldehyde-based resins for wrinkle resistance or color fixing, but elastic watch bands do not typically require these treatments. No recalls or reports link Polar bands to formaldehyde off-gassing. Risk is low for this product type.

Source, ATSDR
95/ 100
⛏️

Heavy metals

Polar bands are typically dyed nylon, but no specific contamination or recalls have been reported. Standard nylon dyeing with acid or disperse dyes does not inherently pose lead or cadmium risk. Brand does not market bands as heavy-metal-tested, but this is not unusual for the category.

Source, FDA
95/ 100

Antimony in polyester backing or reinforcement

Some elastic bands use polyester reinforcement threads or backing; antimony trioxide is a known catalyst in polyester synthesis. Polar does not disclose band construction details. If polyester is used, antimony leaching at body temperature is unlikely, but the material composition is not transparent enough to rule out entirely.

95/ 100

The full breakdown

What it's made of and why it matters

Polar Elastic Nylon Watch Band is a synthetic elastomeric textile, likely a blend of nylon 6 or nylon 6.6 with spandex or similar elastic fibers to provide stretch and comfort around the wrist. The material requires a water-resistant or water-repellent finish to function as a sports watch strap, which typically involves fluorinated compounds (PFAS family) or silicone-based coatings. Nylon itself is stable at body temperature and poses minimal leaching risk, but the finishing treatment is the primary source of concern and is not disclosed by Polar.

The brand's record and disclosure

Polar is a Finnish sports watch and fitness tracker manufacturer with no published statements on PFAS use, chemical restrictions, or textile certifications (OEKO-TEX, bluesign) in their supply chain. The company does not provide detailed material safety datasheets for bands or disclose waterproofing chemistry. Polar has not faced major public recalls or controversies involving textile hazards, but the silence on water-resistant treatment specifics is a transparency gap typical of the budget sports accessory market.

How it compares in its category

Watch bands in this segment typically use the same nylon-elastane blends and rely on water-repellent coating (water-repellent coating) finishes; most manufacturers do not disclose whether they use PFAS-based or fluorine-free alternatives. Polar's elastic band is standard for fitness tracker replacements and poses no unique toxicity risk relative to competitors like Garmin, Fitbit, or Apple sport bands, which also lack transparency on finishing agents. The main differentiation is availability and price, not safety profile.

If you buy it

Wash the band in cool to warm (not hot) water with mild soap; high heat or direct sunlight can degrade nylon and may accelerate any coating breakdown. Avoid prolonged contact with chlorine, saltwater, or strong solvents, which can weaken elasticity and compromise water resistance. Replace the band if it shows visible cracking, color bleeding, or loss of stretch (typically 12-24 months of regular use). Store dry and away from direct heat when not in use.

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
Polar has made none

Formulations change between production runs, so check the current label. How we grade.

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More water-resistant smart rings & bands 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.