PFAS85/ 100Excellent
Overall67/ 100Good
Moto Watch M40 Smartwatch with Silicone Band

Moto · Waterproof Fitness Trackers & Cases

Moto Watch M40 Smartwatch with Silicone Band

Excellent

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

Verdict · BuySilicone band poses minimal known hazards; no brand disclosure gaps on non-PFAS safety; typical for category.

The product information we reviewed describes silicone 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

Silicone 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

Silicone band degradation and microfragmentation

Long-term UV and heat exposure may cause silicone to become brittle and shed small particles; however, any fragments are biologically inert and pose no chemical toxicity, only potential minor ingestion risk if not regularly inspected for visible cracking.

70/ 100
⚠️

Bacterial and fungal growth on band

Silicone's porous surface can harbor moisture and sweat residue, creating conditions for skin flora overgrowth if the band is not dried and rinsed regularly; this is a hygiene issue (contact dermatitis risk) rather than chemical hazard.

45/ 100
⚠️

Allergens in silicone or dyes

Silicone rubber itself is hypoallergenic, but uncured oligomers or colorant additives (e.g., azo dyes in darker bands) may trigger mild contact sensitivity in rare cases; pre-wear rinsing and spot-testing on inner wrist can mitigate risk.

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

Adhesive or sealant leachables in watch housing

No adhesives or sealants are specified in product documentation; typical smartwatch assembly uses minimal epoxy or urethane adhesives in sealed sections that do not contact skin.

95/ 100
🧠

Lead

The M40 meets RoHS and likely CE standards for electronics, which restrict these metals; however, no third-party teardown or certification document is publicly available for this specific model to confirm.

Source, ATSDR
95/ 100

The full breakdown

What it's made of and why it matters

The Moto Watch M40 uses a silicone elastomer band, which is a synthetic rubber polymer selected for flexibility, water resistance, and durability in wearables. Silicone does not leach BPA, phthalates, or heavy metals under normal skin-contact conditions, and it resists degradation from sweat and moisture. The watch body material is not specified in available product documentation, but typical Moto smartwatch housings use aluminum or stainless steel with plastic bezels, neither of which pose significant leaching risks in short-term contact.

The brand's record and disclosure

Motorola (Moto parent company) does not publish dedicated material safety or chemical disclosure statements for wearables in the public domain. No recalls or documented safety incidents are on record for the M40 band or housing. The brand's silence on PFAS and other restricted substances is typical for the smartwatch segment, where transparency lags behind cookware and apparel manufacturers; this reflects industry practice rather than unusual risk.

How it compares in its category

Silicone bands are the industry standard for fitness trackers and smartwatches, chosen precisely because they avoid phthalate-softened PVC and BPA-leaching plastics common in older wearables. The M40 sits in the mainstream mid-range; competitors like Fitbit, Garmin, and Apple Watch use identical silicone materials. The lack of stated coatings or special treatments (e.g., antimicrobial finishes) actually reduces potential hazard surfaces compared to some premium models.

If you buy it

Rinse the silicone band with fresh water after prolonged sweat or saltwater exposure to prevent bacterial biofilm buildup and odor, which are hygiene concerns, not toxicity ones. Avoid prolonged storage in direct sunlight or heat above 60 degrees Celsius, as silicone can degrade and become sticky over years of use. If the band develops cracks, permanent discoloration, or loss of elasticity after 2-3 years, replacement is advisable; official Moto bands are inexpensive. The watch body itself requires no special care beyond standard electronics handling (keep dry, avoid impacts).

What we don’t know

Basis
Model estimate, 35% confidence, not a lab result
Lab test
None on record for this exact product
Brand statement
Moto has made none

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

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.