Apple · Waterproof Fitness Trackers & Cases
Apple Watch Series 9 GPS + Cellular Aluminum Case
Waterproofing methods and PFAS content remain unknown.
Series 9 uses aluminum, glass, and elastomer seals with undisclosed protective coatings. Apple provides no PFAS information; waterproofing commonly contains PFAS.
The better-graded swap
Fitbit
Google Fitbit Air Active Band
85/100 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
Aluminum case, ion-X glass, fluoroelastomer seals, proprietary coatings
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.
PFAS
Fluoroelastomer seals and unnamed proprietary coatings used for 50-meter water resistance likely contain PFAS; Apple discloses zero information. This is not specific to the Series 9 but to the entire product line and Apple's complete opacity on the issue.
Source, ATSDR ↗Fluoroelastomer seal degradation and microfragment release
Fluoroelastomer degrades over 2-3 years with UV and thermal cycling; breakdown products may include small elastomer fragments. The volume and toxicological significance are unknown; no data exists on inhalation or ingestion risk from a wearable device.
Brand transparency and recall responsiveness
Apple's historical pattern of minimal material disclosure and slow public response to supply chain concerns means chemical hazards may not be communicated to consumers. No smartwatch-specific recalls have occurred, but the lack of pre-market transparency limits consumer-driven risk assessment.
What’s reassuring
Anodized aluminum skin contact
Anodized aluminum forms a stable oxide barrier and does not leach aluminum ions under normal pH and contact conditions. No cases of dermatitis or systemic exposure have been reported from anodized watch cases.
Ion-X glass breakage and skin contact
Proprietary ion-X glass does not contain known carcinogens or heavy metals. Breakage is mechanically hazardous (sharp edges) but not chemically hazardous; no toxicological data suggests the glass formulation poses hazards beyond mechanical injury.
The full breakdown
What it's made of and why it matters
The Series 9 aluminum case is anodized aluminum alloy, which creates a protective oxide layer that resists corrosion and leaching under normal use. Ion-X glass front is a proprietary hardened glass that does not contain known toxicants. Fluoroelastomer seals and proprietary surface coatings enable water resistance to 50 meters, but Apple does not disclose the chemical composition of these coatings or whether they contain PFAS compounds used in water and stain repellency.
The brand's record and disclosure
Apple publishes environmental reports but does not disclose specific chemical hazards, material certifications, or PFAS content in wearables. The company has faced criticism for opacity on supply chain safety and does not participate in third-party material auditing programs like Cradle-to-Cradle or Bluesign. No recalls have been issued for this product class due to leaching or coating breakdown.
How it compares in its category
Smartwatches as a category avoid most traditional cookware hazards (no lead glazes, no aluminum cooking exposure). The Series 9 sits in the premium tier; competitors like Garmin and Fitbit similarly withhold proprietary coating details. Apple's anodized aluminum approach is chemically stable compared to painted steel or uncoated aluminum, but the lack of transparency on waterproofing chemistry is consistent across the industry.
If you buy it
Anodized aluminum will not leach under normal skin contact or freshwater exposure. Avoid abrasive cleaning that scratches the anodized layer; use soft cloth and mild soap. The fluoroelastomer seals degrade over time and may lose water resistance after 2-3 years; Apple offers replacement bands but not seal refurbishment. Do not expose to saltwater or chlorinated pools for extended periods, as these can degrade seals and coatings faster.
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
- Apple has made none
Formulations change between production runs, so check the current label. How we grade.
Better-graded alternatives in Waterproof Fitness Trackers & Cases
TomTom
Water Resistant Watch Model 8R500 - Men
On watch case and band
Polymer case and band degradation
Limited concern
Bacterial or mold growth in seals and band
Limited concern
No coating described, and no PFAS statement from the brand.
⚠Brand says nothing about PFAS
TomTom
Tom Tom Sport Runner Wrist Watch Model 8rs00 Water Resistant Wide Band
Plastic/elastomer band
Coating degradation and peeling
Limited concern
Bacterial or mold growth in band seams
Limited concern
No coating described, and no PFAS statement from the brand.
⚠Brand says nothing about PFAS
TomTom
Black Tomtom Water Resistant Watch Model 8rs00 With Wristband
Plastic/elastomer wristband, exact
Elastomer degradation and off-gassing
Limited concern
Bacterial growth in seals and crevices
Limited concern
Contact dermatitis from additives or microbial buildup
Limited concern
No coating described, and no PFAS statement from the brand.
⚠Brand says nothing about PFAS
More waterproof fitness trackers & 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.