Withings · Waterproof Smartwatches & Fitness Trackers
Withings Pulse O2 Activity Tracker
Waterproof activity tracker; coating type undisclosed, PFAS risk unclear.
Withings does not publicly disclose PFAS or coating materials for this device. Waterproof electronics typically use water-repellent treatments that may contain PFAS, though brand transparency is absent.
The safe swap
Swatch
Swatch Chrono 42 Quartz Watch
85/100 safety
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
Plastic casing, elastomer band, waterproof coating (type unspecified)
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.
Category baseline
other is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
The full breakdown
What it's made of and why it matters
The Pulse O2 uses a plastic casing (likely polycarbonate or similar engineering polymer) paired with an elastomer band (commonly silicone or thermoplastic rubber) and an unspecified waterproof coating. The coating is the critical unknown: waterproof electronics typically rely on either Teflon-family coating (Teflon-type coating-family, high PFAS risk) or polyurethane-based systems (lower PFAS but different durability profile). Withings has not disclosed which technology protects this device, leaving the primary chemical hazard opaque to consumers.
The brand's record and disclosure
Withings (acquired by Nokia Health in 2018, later rebranded as Withings again) has not published material safety data sheets or PFAS policy statements for wearable devices. The brand's transparency on chemical composition remains limited across its activity tracker line. No major recalls or chemical controversies are documented for the Pulse O2 specifically. Absence of disclosure is not absence of hazard, but also does not confirm presence; the lack of a public stance on PFAS or waterproof coating chemistry makes independent verification difficult.
How it compares in its category
Fitness trackers generally carry lower chemical hazard profiles than cookware or textiles because they have minimal skin contact duration and no food/fluid ingestion pathway. However, wearables with undisclosed waterproof coatings are less transparent than competitors (e.g., Garmin, Apple) who sometimes specify polyurethane or other non-Teflon-family coating systems. The Pulse O2's main risk sits in the unknown coating chemistry rather than the plastic or elastomer band themselves, which are commodity materials with established safety histories when not degraded.
If you buy it
Avoid prolonged immersion beyond the rated water resistance (typically 5 ATM / 50 meters for swim-ready trackers); repeated pressure flexing of the band or casing can accelerate coating micro-cracking and material leaching. Do not expose to solvents, alcohol-based cleaners, or extreme heat (>60°C), which can degrade elastomer and coating. Inspect the band and seams annually for visible wear, discoloration, or peeling; replace if degradation is apparent. Remove and air-dry fully after water contact to prevent bacterial or mold growth under the band.
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.”
Waterproof coating composition (unspecified)
Withings has not disclosed whether the waterproof coating contains Teflon-family coating (high PFAS probability) or alternative polymers (lower PFAS risk). This is the primary chemical uncertainty for this product. Without manufacturer data, independent assessment is not feasible.
Elastomer band degradation and skin contact
Silicone and thermoplastic rubber bands are generally well-tolerated on skin. However, aging or UV exposure can cause leaching of residual oligomers or plasticizers; regular inspection and replacement every 2-3 years of heavy use is prudent, though no specific toxicity reports exist for this model.
Bacterial or fungal growth under band
Moisture trapped between the elastomer band and skin, especially if the device is not fully dried after water exposure, can promote microbial colonization. This is a hygiene issue rather than chemical toxicity, but relevant to safe daily wear.
Plastic casing leachables (unspecified plastic type)
If the casing is polycarbonate, potential BPA leaching exists under heat or stress, though wearable-grade engineering plastics are typically low-migration. No recalls or specific hazard reports exist for the Pulse O2 casing material.
Coating delamination and micro-particle exposure
If the waterproof coating degrades over time (especially after repeated water exposure or pressure flexing), micro-particles of the coating may become loose. The health significance depends on coating chemistry, which is undisclosed; precautionary replacement before visible peeling is advisable.
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
Stainless steel case, mineral/plastic crystal, standard watch components
Lower concern. Standard watch materials pose minimal PFAS risk.
⚠Brand says nothing about PFAS
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SEA WASP
Plastic/resin watch case and strap
Typical consumer watch, no known PFAS risk signal identified
⚠Brand says nothing about PFAS
Swatch
Neon Seppia Big Bold Chrono Quartz Watch
Stainless steel case, plastic/resin band, mineral or acrylic crystal
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.