Fitbit · Waterproof Smart Rings & Bands
Fitbit Charge 6 Activity Tracker Smart Ring Size 9 Silver Black
Wearable with waterproofing; coating details undisclosed.
Fitbit Charge 6 is water-resistant but brand does not disclose coating materials or PFAS status. Waterproof treatments in wearables often use PFAS, though some alternatives exist. No independent testing available for this model.
The safe swap
Fitbit
Oura - Ring 5 - Smart Ring - Size Before You Buy with OR5 Sizing Kit - Size 11 - Silver - (2026)
85/100 safety
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Stainless steel, elastomer, unknown waterproof coating
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 Fitbit Charge 6 combines stainless steel (likely 304 or similar food-grade alloy), elastomer bands (composition unspecified by manufacturer), and an undisclosed waterproof coating system. Stainless steel itself is stable and non-leaching under normal skin contact. The elastomer band material is the primary concern: manufacturers rarely disclose whether bands contain phthalates, BPA, or other plasticizers, and repetitive skin contact plus sweat exposure can accelerate migration of these compounds. The waterproof coating remains the largest unknown, as Fitbit has not publicly detailed whether it uses Teflon-type coating, silicone, polyurethane, or other polymers.
The brand's record and disclosure
Fitbit (owned by Google since 2021) provides minimal material safety documentation beyond general water-resistance claims. The company does not publish ingredient lists, coating specifications, or third-party safety certifications for Charge 6 materials. No major recalls or contamination incidents specific to this model are on record, but Fitbit's silence on polymer and coating composition mirrors broader industry avoidance of transparency on wearable materials. Google's parent company has faced criticism over PFAS use in other consumer electronics, though Fitbit has not issued a formal PFAS stance or commitment to phase-out.
How it compares in its category
Wearable activity trackers typically present lower chemical exposure risk than cookware or textiles because contact is external and intermittent, and no food or ingestion pathway exists. However, Fitbit Charge 6 sits at the lower end of transparency compared to premium competitors: Oura Ring discloses titanium and biocompatible materials more explicitly, while Garmin offers some material certifications. Most wearables (Fitbit, Apple Watch, Garmin) share the same opacity on elastomer composition and coating systems, making Charge 6 representative of industry norms rather than an outlier.
If you buy it
Remove the device during activities involving prolonged moisture, chlorine, or salt water exposure, as these can accelerate elastomer degradation and potential leaching. Clean the band regularly with mild soap and water, and allow it to dry fully before reapplication to skin. Replace the elastomer band every 12-18 months if visibly degraded, discolored, or if skin irritation develops. Store the device in a cool, dry place away from direct sunlight to minimize polymer aging; do not expose to heat sources or leave in hot vehicles, as elevated temperature can increase migration of any residual plasticizers.
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.”
Elastomer band composition (phthalates/plasticizers)
Fitbit does not disclose elastomer material or certifications (phthalate-free, BPA-free, etc.). Typical silicone and TPE bands used in wearables may contain residual plasticizers; direct skin contact and sweat exposure present a minor but unquantified pathway for migration.
Waterproof coating leachables
The coating system used for water resistance is not disclosed. If Teflon-type coating-based or polyurethane-based, degradation under UV, heat, or friction could release oligomers or monomers; no test data publicly available for Charge 6.
Stainless steel nickel content
Food-grade 304/316L stainless steel typically contains controlled nickel (8-10%) and is generally safe for skin contact. No recalls or complaints specific to nickel allergies from Charge 6 are on record, though nickel-sensitive individuals should monitor for localized dermatitis.
Strap degradation and microparticle release
Elastomer bands degrade over time through UV, ozone, thermal stress, and mechanical wear. Microscopic elastomer particles may shed onto skin during prolonged wear; long-term health effects of this exposure remain unstudied in wearables.
Electronic device thermal runaway or battery leakage
Fitbit Charge 6 uses standard lithium-ion cells with established safety standards. No battery leaks, thermal incidents, or chemical burns are documented for this model. Standard precautions (avoid crushing, extreme heat, water submersion) apply.
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 Smart Rings & Bands
Fitbit
Oura - Ring 5 - Smart Ring - Size Before You Buy with OR5 Sizing Kit - Size 11 - Silver - (2026)
Titanium and stainless steel with glass sensor
Lower concern smart ring; no PFAS-prone materials identified.
⚠Brand says nothing about PFAS
Fitbit
Qalo QRNT Slim Smart Ring
silicone elastomer with metal core
Smart ring with silicone body; lower concern but no public PFAS disclosure.
⚠Brand says nothing about PFAS
Withings
Black Smart Ring Size 9 - New Women | Color: Black
Titanium alloy ring with sapphire crystal display
Lower concern. Smart ring materials inherently unlikely to require PFAS.
⚠Brand says nothing about PFAS
More waterproof 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.