40/ 100
F
OverallF10/100
Withings Scanwatch HWA09 Hybrid Smartwatch

Withings · Waterproof Smartwatches & Fitness Trackers

Withings Scanwatch HWA09 Hybrid Smartwatch

F · High PFAS

Waterproofing unknown; insufficient PFAS transparency for smartwatch.

Verdict: SkipStainless steel and sapphire construction minimizes chemical leaching; PFAS waterproofing chemistry undisclosed; moderate durability concern for elastomer band degradation.

Hybrid smartwatch with water resistance and stainless steel construction. Withings provides no PFAS disclosure; waterproofing method unstated, creating moderate uncertainty.

The safe swap

Swatch Chrono 42 Quartz Watch

Swatch

Swatch Chrono 42 Quartz Watch

85/100 safety

B

Same rubric that flunked this product. The swap earned its B.

Still want this one anyway? Check the price on Amazon. We’d swap it.

Material

stainless steel, sapphire crystal, elastomer band

Brand disclosure

Brand is silent on PFAS

Lab data

No public lab test

Why this grade

Waterproof / stain-resistant treatment

water-repellent coating treatments have historically used PFAS.

Hurts the grade

Category baseline

other is a category where PFAS exposure is more common.

Hurts the grade

No PFAS disclosure

No public statement about PFAS in this product.

Hurts the grade

The full breakdown

What it's made of and why it matters

The Scanwatch HWA09 uses 316L stainless steel (watch body), sapphire crystal (screen), and elastomer (rubber/synthetic polymer band). Stainless steel is chemically stable and does not leach metals under normal skin contact. Sapphire crystal is inert and extremely durable. The elastomer band is the variable component: elastomers can degrade over time with sweat exposure, UV light, and repeated flexing, potentially releasing breakdown products or becoming sticky or brittle.

The brand's record and disclosure

Withings has not published detailed material safety data sheets, PFAS sourcing information, or third-party safety certifications for the Scanwatch line. The company does not publicly disclose chemical composition of the elastomer band or confirm absence of flame retardants, phthalates, or other synthetic additives common in elastomers. No major recalls affecting the Scanwatch HWA09 have been documented for chemical hazards, but transparency around waterproofing chemistry (which often relies on fluorinated compounds) remains absent.

How it compares in its category

Most hybrid smartwatches use identical material combinations (stainless steel, sapphire, elastomer). Few brands disclose elastomer composition; Garmin and Apple similarly lack detailed breakdowns. The Scanwatch's advantage is lower overall electronic complexity and battery life reduce need for frequent device replacement. However, absence of stated material certifications (e.g., FDA biocompatibility for elastomer, phthalate-free) is standard across the category, not a differentiator.

If you buy it

Rinse the elastomer band weekly with fresh water after sweating to reduce bacterial buildup and slow polymer degradation. Avoid extended direct sunlight exposure, which accelerates elastomer brittleness. Replace the band every 2-3 years or sooner if it becomes visibly cracked, sticky, or develops an odor (sign of microbial growth or polymer breakdown). Do not expose the watch to high heat (>60°C) or aggressive chemicals; the elastomer can soften or leach additives under thermal or chemical stress.

Beyond PFAS: other things we checked

Established hazard classes for this product type, assessed from public information. These never change the PFAS grade; a Likely flag caps the Verdict at “Buy with care.”

Possible

Elastomer band degradation and additive leaching

Elastomer bands commonly contain plasticizers (phthalates or non-phthalate alternatives) and colorants. With extended sweat exposure and UV exposure, degradation can occur, potentially releasing these additives to skin. Withings does not disclose elastomer composition or confirm phthalate-free status.

Possible

Bacterial and fungal growth on band

Elastomer bands are porous and accumulate sweat, dead skin cells, and moisture. Poor cleaning or constant wear creates conditions for bacterial and fungal proliferation, which can cause dermatitis or infection in susceptible individuals. No antimicrobial treatment is disclosed for the Scanwatch band.

Likely

Waterproofing chemistry (PFAS surrogate)

The Scanwatch claims 50m water resistance but Withings does not disclose whether fluorinated compounds (PFAS-family or legacy PFOA/PFOS analogs) are used in sealants, coatings, or elastomer treatment. This is common in smartwatch waterproofing but undisclosed here.

Possible

Stainless steel nickel content and skin sensitivity

316L stainless steel contains nickel (typically 8-12%). Most users tolerate this; however, individuals with nickel contact dermatitis may experience reactions with prolonged skin contact, especially if the watch is worn tightly or in humid conditions that promote ion leaching.

None known

Sapphire crystal coatings

Withings has not disclosed whether the sapphire crystal has anti-reflective or oleophobic coatings. Some sapphire watches use Teflon-family coating or silicone-based treatments; if present, their safety profile is not disclosed. Natural sapphire itself poses no chemical hazard.

What we don’t know

This grade is a model-based estimate from public materials, coatings, and brand disclosure at 45% confidence. It is not a lab result.

No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.

The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.

Formulations and coatings change between production runs. Always check the current label before buying.

Safer alternatives in Waterproof Smartwatches & Fitness Trackers

Swatch Chrono 42 Quartz Watch

Swatch

Chrono 42 Quartz Watch

Stainless steel case, mineral/plastic crystal, standard watch components

B
C
PFASAll
B · Low PFAS2 flags

Lower concern. Standard watch materials pose minimal PFAS risk.

Brand says nothing about PFAS

Swatch SEA WASP

Swatch

SEA WASP

Plastic/resin watch case and strap

B
C
PFASAll
B · Low PFAS2 flags

Typical consumer watch, no known PFAS risk signal identified

Brand says nothing about PFAS

Swatch Neon Seppia Big Bold Chrono Quartz Watch

Swatch

Neon Seppia Big Bold Chrono Quartz Watch

Stainless steel case, plastic/resin band, mineral or acrylic crystal

B
C
PFASAll
B · Low PFAS2 flags

Lower concern. Standard watch materials typically lack intentional PFAS use.

Brand says nothing about PFAS

More waterproof smartwatches & fitness trackers 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.