PFAS85/ 100Excellent
Overall77/ 100Excellent
Withings Pulse O2 Activity Tracker

Withings · Waterproof Smartphone Cases

Withings Pulse O2 Activity Tracker

Excellent

No coating described, and no PFAS statement from the brand.

Verdict · BuyPlastic activity tracker with elastomer band presents minimal established hazards; no coating treatments identified; routine care and occasional replacement mitigate wear risks.

The product information we reviewed describes plastic casing, elastomer band, with no water-repellent coating named. Water resistance on products like this usually comes from the material and its seals rather than a surface treatment. The brand has published no PFAS statement for it.

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We flunk more products than we pass. This one earned its grade. How we grade

Material

Plastic casing, elastomer band

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

Elastomer band degradation and skin irritation

Elastomer materials can degrade with sweat, UV exposure, and age, potentially releasing residual monomers or becoming irritating to sensitive skin. This is not unique to Withings; it is a material-class limitation of all elastomer wristbands in this price and category.

70/ 100
🫧

Microplastic shedding from band wear

Extended use of elastomer bands can produce microscopic particles if the material fractures or fragments. Risk increases with age and UV exposure but is generally minimal in normal indoor-wear patterns.

70/ 100

What’s reassuring

Base material not linked to PFAS

The main material recorded for this product is not one associated with PFAS.

100/ 100
🍼

BPA & bisphenols

The rigid plastic shell is unlikely to contact skin or ingestion routes in normal use. No specific BPA content is disclosed, but hard plastics (polycarbonate, ABS) in consumer electronics typically comply with RoHS and REACH limits in the EU and North America.

Source, FDA
95/ 100

Coating degradation or unknown surface treatments

The known context specifies no coating is described on this device. The waterproofing derives from sealed seams and material properties, not applied finishes, so no coating-related hazards are identified.

95/ 100
⛏️

Heavy metals

No recalls or testing has identified heavy metal contamination in the Pulse O2 casing or band. Reputable manufacturers typically source plastics and dyes meeting toy safety and consumer electronics standards, though Withings does not publicly certify compliance.

Source, FDA
95/ 100

The full breakdown

What it's made of and why it matters

The Pulse O2 casing is rigid plastic (likely polycarbonate or ABS) with an elastomer (rubber-like) wristband. Neither material typically leaches harmful chemicals during normal skin contact at body temperature. The plastic shell is non-porous and sealed; the elastomer band does not contact food or drinks, eliminating the primary routes for migration of residual monomers or plasticizers. No thermal stress occurs in normal use since the device operates at ambient temperatures well below plastic degradation points.

The brand's record and disclosure

Withings (now part of Nokia Health) has not published a dedicated PFAS statement or publicly disclosed manufacturing chemistry for this wearable. The company maintains a general focus on health data privacy and regulatory compliance but does not appear in prominent transparency initiatives for materials. No recalls or safety controversies are documented for the Pulse O2 in relation to plastic leachates or coating hazards. Limited disclosure reflects typical industry practice for low-cost wearables rather than a specific red flag.

How it compares in its category

This activity tracker sits in the mainstream consumer wearable category; competitors (Fitbit, Garmin, Apple Watch) use identical plastic and elastomer construction with similar disclosure gaps. The Pulse O2's sealed design and lack of reported coating treatments place it on par with or slightly ahead of competitors that may use unknown protective finishes. No material advantage or disadvantage is evident within the category based on publicly available information.

If you buy it

Rinse the band with fresh water weekly and allow it to dry fully to prevent bacterial growth or skin irritation from sweat accumulation. Avoid prolonged immersion in hot water (above 60 Celsius / 140 Fahrenheit) to preserve elastomer flexibility, though the device is designed for water resistance in daily use and swimming. If the band shows visible cracking, discoloration, or hardening after 1-2 years, replace it; the plastic casing typically remains stable longer. Store in a cool, dry place to slow elastomer degradation if not worn daily.

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
Withings has made none

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

More waterproof smartphone cases 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.