95/ 100
A
OverallB83/100
Hammered Stainless Steel Tumbler

Cuppa · Insulated Drink Tumblers

Hammered Stainless Steel Tumbler

A · Very low PFAS

Lower concern. Bare stainless steel has no coating requiring PFAS.

Verdict: BuyBare stainless steel tumbler with no coatings, enamels, or plastic liners; no established safety concerns beyond normal use.

Stainless steel tumblers are inherently PFAS-free materials with no coatings or treatments. No brand disclosure needed; material itself carries minimal risk.

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We flunk more products than we pass. This one earned its grade. How we grade

Material

Stainless steel, bare/uncoated

Brand disclosure

Brand is silent on PFAS

Lab data

No public lab test

Why this grade

Uncoated safe material

Bare, uncoated material (cast iron, stainless, carbon steel, or glass) with no surface treatment to contain PFAS.

Helps 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

This tumbler is made from stainless steel with a hammered finish, meaning the surface has been mechanically textured but contains no polymer coatings, enamel glazes, or Teflon-type coating (Teflon) linings. Stainless steel is an iron-chromium-nickel alloy chosen for drinkware because it resists corrosion and does not leach appreciable metals into beverages under normal use conditions. The absence of any topcoat eliminates the primary source of hazards in coated cookware and drinkware (peeling coatings, Teflon-type coating fume risk, lead in glazes).

The brand's record and disclosure

Cuppa has no publicized safety certifications, third-party testing disclosures, or material origin statements readily available in open sources. The brand has not made a stated position on PFAS or heavy metals testing. No recalls or safety controversies associated with Cuppa stainless steel tumblers appear in public records. Without active transparency, there is no way to verify manufacturing origin or QA standards for this specific product line.

How it compares in its category

Uncoated stainless steel tumblers are among the safest reusable drinkware options available, functionally identical to premium brands (Yeti, Hydro Flask) in material safety profile. Many competitors add double-wall insulation via welded seams and plastic or silicone bases, which can introduce leachable materials; this product's bare design avoids those vectors. The hammered finish is purely aesthetic and does not alter the safety chemistry of the steel.

If you buy it

Stainless steel is durable and does not require special handling for daily beverage use. Avoid prolonged storage of acidic liquids (vinegar, lemon juice, wine) as acidity can very slowly promote surface discoloration, though leaching is negligible. Hand-wash or use dishwasher; both are safe. Replace only if the seal or structural integrity is compromised; bare steel does not degrade chemically with age.

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

Nickel leaching from stainless steel

Stainless steel does contain nickel as an alloying element. Leaching into beverages is minimal under normal pH conditions but may increase slightly with acidic or hot contents. Individuals with nickel sensitivity (contact dermatitis) may prefer alternatives; the risk is not a safety defect but a personal tolerance issue.

None known

Chromium leaching

Chromium in stainless steel is stabilized as Cr(III) and does not leach into neutral or slightly acidic beverages under standard use. No public reports of chromium release from uncoated stainless steel drinkware exist.

None known

Coating degradation and peeling

This product has no applied coating, enamel, or polymer lining, so peeling or flaking hazards do not apply. The bare steel surface may develop surface discoloration over time but does not shed fragments.

Possible

Manufacturing contaminants (heavy metals in steel)

Without third-party material testing or manufacturing audits disclosed by Cuppa, it is not possible to rule out trace heavy metals (lead, cadmium, arsenic) in the raw steel. Food-grade stainless steel typically meets FDA 21 CFR 173.350 limits, but Cuppa has not published compliance documentation.

Possible

Bacterial growth (if damp for prolonged periods)

The hammered texture creates microscopic crevices where bacteria or mold can colonize if the tumbler is left wet without drying. This is a use and care issue, not a material defect; regular washing and air-drying mitigates risk.

What we don’t know

This grade is a model-based estimate from public materials, coatings, and brand disclosure at 88% 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.

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More insulated drink tumblers 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.