Xiaomi · Waterproof Smartwatches & Fitness Trackers
Xiaomi Smart Band 9 Pro Smartwatch
Skip until Xiaomi discloses waterproof treatment chemistry.
Xiaomi provides no PFAS information for this smartwatch. Waterproof coating composition is undisclosed, raising uncertainty about potential PFAS-based water-repellent coating treatments commonly used in wearables.
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
Aluminum alloy case, elastomer strap, unspecified 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 Xiaomi Smart Band 9 Pro uses an aluminum alloy case, which is lightweight and corrosion-resistant but can react with sweat and acidic skin chemistry over prolonged contact. The elastomer strap (rubber-like polymer) is the primary skin-contact material and typically contains minimal hazardous additives in modern formulations, though composition is not detailed in public specs. The waterproof coating applied to achieve water resistance is the least transparent component; Xiaomi does not disclose whether it uses PFAS-based hydrophobic treatments (standard in the industry) or alternatives.
The brand's record and disclosure
Xiaomi has not published detailed material safety data sheets or chemical transparency reports for wearables. The company does not publicly commit to PFAS-free waterproofing or provide third-party test results for heavy metals or off-gassing. Xiaomi has no documented major product recalls related to material toxicity in wearables, but the absence of disclosure does not indicate absence of risk. The brand's silence on waterproof chemistry is the critical gap here.
How it compares in its category
Smartwatch wearables rarely disclose waterproof coating chemistry; Xiaomi's transparency is typical for the budget-to-mid segment. Premium competitors (Apple, Garmin) also use undisclosed fluorinated coatings. Unlike dedicated fitness trackers or rings, the Smart Band 9 Pro is a larger device with greater potential for prolonged skin contact, which marginally increases relevance of elastomer composition. No category leader has committed to PFAS-free waterproofing at this price point.
If you buy it
Rinse the strap regularly with fresh water after sweating or swimming to minimize salt and acid buildup on both aluminum and elastomer surfaces. Do not soak or submerge the band in hot water or chlorinated pools for extended periods, as elastomers can absorb chemicals and degrade. Inspect the strap quarterly for cracking, discoloration, or odor; replace if visible wear appears. If you have sensitive skin or metal allergies, patch-test the aluminum case contact area first and consider use of a protective strap alternative.
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.”
Aluminum alloy dermal contact and corrosion
Aluminum in contact with sweat and body oils can corrode and leach trace aluminum. Risk is low-to-moderate for daily wear; individuals with eczema or metal sensitivities face higher risk. No recall data exists for this product line.
Elastomer strap additives (phthalates, BPA)
Xiaomi has not disclosed elastomer formulation. Modern silicone and rubber straps typically avoid legacy phthalates and BPA, but verification is unavailable. Prolonged skin contact in warm conditions can increase any leaching risk.
Waterproof coating chemistry (undisclosed, likely PFAS)
Industry standard for water-resistant electronics is Teflon-family coating (PFAS-based) coating. Xiaomi's silence on this treatment leaves it unconfirmed for this model. Coating degradation over years of UV and thermal stress may increase shedding risk.
Off-gassing from adhesives and sealants
No public data on off-gassing from internal adhesives or seals. Wearables are rarely tested for VOC emissions because skin contact is localized and ventilation is high, but long-term strap odor changes should be monitored.
Battery leakage and electrolyte contact
Embedded lithium-ion battery poses risk if casing is damaged (cracked elastomer allowing water ingress). Direct electrolyte contact with skin is unlikely under normal use but possible after impact or submersion. No specific incident reports for this model are public.
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
Swatch
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.