50/ 100
F
OverallF32/100
Ember 16 oz Smart Tumbler

Ember · Insulated Travel Drinkware

Ember 16 oz Smart Tumbler

F · High PFAS

Unknown internal coating; Ember has not disclosed PFAS status.

Verdict: SkipStainless steel construction is low-risk, but unspecified internal coating and Ember's PFAS silence warrant cautious use pending disclosure.

The Ember Smart Tumbler uses stainless steel construction but does not publicly disclose materials or PFAS status of internal coatings. No third-party verification available.

The safe swap

Ember Cold Tumbler

Ember

Ember Cold Tumbler

100/100 safety

A

Still want this one anyway? Check the price on Amazon. We’d swap it.

Material

stainless steel with unspecified internal coating/sealant

Brand disclosure

Brand is silent on PFAS

Lab data

No public lab test

Why this grade

Unknown / proprietary coating

Proprietary coating with no disclosed chemistry.

Hurts the grade

Category baseline

other is a category where PFAS exposure is more common.

Hurts the grade

No PFAS disclosure

No public statement about PFAS in this product.

Hurts the grade

The full breakdown

What it's made of and why it matters

The Ember 16 oz tumbler uses food-grade stainless steel as its primary material, which is inherently corrosion-resistant and does not leach metals under normal use. The critical unknown is the internal coating or sealant used to protect the heating element and electronics from liquid contact. Ember has not publicly specified whether this coating contains Teflon-type coating (Teflon), epoxy resins, or other polymer barriers that could degrade or off-gas over time, especially with hot beverages.

The brand's record and disclosure

Ember does not appear to have published material safety data sheets, PFAS testing results, or coating certifications in public domains. The brand has not addressed PFAS presence or absence in response to consumer inquiries on this product line, which is notable given industry-wide scrutiny of smart drinkware. No major recalls or safety incidents have been widely documented for this model, though the product's relative newness limits long-term safety history.

How it compares in its category

Smart tumblers are a niche category with minimal standardization. Compared to conventional insulated tumblers (stainless steel only), the Ember introduces internal electronics and coatings, expanding potential exposure surfaces. Competitors rarely disclose internal coating composition either, making direct comparison difficult. Non-electronic stainless steel alternatives eliminate the coating risk entirely but sacrifice the temperature-control feature.

If you buy it

Avoid prolonged exposure of hot or acidic liquids (citrus, vinegar, wine) to the interior surfaces if possible, as these conditions may accelerate coating wear. Do not use in dishwashers or expose to extreme temperatures, as the lid and seals may contain polymers sensitive to heat cycling. Inspect the interior periodically for visible coating damage, discoloration, or flaking; discard or contact Ember if degradation appears. If Ember does not respond to a direct request for internal coating composition and PFAS status, consider this a red flag for transparency.

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.”

Possible

Unspecified internal coating degradation

The internal protective coating around the heating element is not publicly identified by material type. Thermal cycling, acidic beverages, or manufacturing defects could cause flaking or leaching into liquids, with composition unknown.

Possible

Polymer leachates from seals and lid

Silicone or elastomer seals and the lid gasket may leach softeners or degradation byproducts when exposed to hot liquids or alcohol-based drinks. No testing data is publicly available for this product.

None known

Electronic component exposure to liquid

The tumbler is designed to be sealed and IP-rated, so direct liquid contact with circuitry is unlikely under normal use. Risk rises only if the seal fails or if the product is disassembled.

None known

Stainless steel corrosion under acidic conditions

Food-grade stainless steel resists corrosion from typical beverages, though prolonged contact with strong acids (vinegar, lemon juice) may cause minor surface pitting. This does not typically release harmful levels of metals.

Reported

Brand transparency and safety accountability

Ember's silence on PFAS and internal material composition is a documented gap in consumer disclosure. No third-party safety certifications (NSF, FDA compliance statements) are prominently available, making verification of manufacturing standards difficult.

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 Insulated Travel Drinkware

Ember Cold Tumbler

Ember

Cold Tumbler

stainless steel with silicone seal

A
A
PFASAll
A · Very low PFAS2 flags

Lower concern; stainless steel tumbler unlikely to contain PFAS.

Naturally PFAS-free material

Ember Tumblers - Set of 4

Ember

Tumblers - Set of 4

Stainless steel double-wall insulated

A
B
PFASAll
A · Very low PFAS3 flags

Lower PFAS concern; stainless steel drinkware rarely treated.

Naturally PFAS-free material

Ember Cup 14 oz Slate Black

Ember

Cup 14 oz Slate Black

Ceramic or ceramic-coated stainless steel with heated base

A
B
PFASAll
A · Very low PFAS2 flags

Lower concern. Smart cup uses ceramic coating, not Teflon-type coating nonstick.

Naturally PFAS-free material

More insulated travel drinkware 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.