85/ 100
B
OverallC77/100
Corkcicle. Pure Taste Tumbler

Corkcicle · Insulated Travel Mugs

Corkcicle. Pure Taste Tumbler

B · Low PFAS

Lower concern. Stainless steel and cork are inherently PFAS-free materials.

Verdict: BuyStainless steel and cork construction poses no established hazards; brand silent on PFAS but materials are inherently PFAS-free.

Corkcicle Pure Taste Tumbler uses stainless steel and cork, materials without known PFAS risk. No Teflon-family coating coatings or water-resistant treatments documented.

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Material

Stainless steel interior, cork exterior

Brand disclosure

Brand is silent on PFAS

Lab data

No public lab test

Why this grade

Safe base material

Made from a material with no inherent PFAS use (ceramic, mineral, or natural fiber).

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

The Pure Taste Tumbler uses food-grade stainless steel (typically 18/8 or similar austenitic alloy) for the interior and natural cork for the exterior sleeve. Stainless steel does not leach heavy metals, reactive metals, or coatings under normal use because the chromium oxide surface layer is passive and inert. Cork is a naturally antimicrobial plant material that does not off-gas volatile organic compounds or require chemical treatments in its raw form, making it a low-chemical choice for a reusable vessel.

The brand's record and disclosure

Corkcicle has not published detailed material safety data sheets or third-party certifications (e.g., NSF, FDA) for the Pure Taste Tumbler publicly available. The brand maintains a silent stance on PFAS; however, stainless steel and cork are inherently free from PFAS because these materials are not treated with water- or grease-repellent coatings. No recalls or safety controversies have been established for this product line.

How it compares in its category

Compared to plastic tumblers (BPA/BPS, phthalate risk) or insulated drinkware with polyurethane foam or adhesive-bonded liners (VOC off-gassing), the stainless steel and cork design avoids synthetic polymers entirely. Against ceramic-lined tumblers (potential lead in glazes) or aluminum-bodied vessels (surface corrosion risk), stainless steel is chemically inert and durable. The cork exterior is a natural alternative to rubber or synthetic grip coatings, reducing chemical additives.

If you buy it

Hand wash with mild soap and warm water; avoid prolonged dishwasher exposure, which may degrade the cork seal over time. Do not use with boiling liquids for extended periods, as extreme heat can stress cork attachment adhesives (though no hazard is documented). Cork may develop surface mold in high-humidity storage; store in a dry environment. Inspect the cork sleeve annually for cracks or separation; if compromised, the seal function declines but the stainless steel core remains safe.

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.”

None known

Cork adhesive or finish composition

Cork is bonded to stainless steel; Corkcicle does not publicly disclose the adhesive formulation. No reports of off-gassing or leachate issues exist for this product, and cork itself is non-toxic.

None known

Stainless steel corrosion or nickel leaching

Food-grade stainless steel (18/8) is stable in contact with beverages and does not leach nickel under normal use conditions. No leaching incidents have been reported for Corkcicle tumblers.

None known

Coatings or surface treatments on cork

Natural cork typically requires no chemical treatment; however, if the exterior is sealed or finished, the formulation is undisclosed. No off-gassing or contact dermatitis reports are on record.

Possible

Microbial growth in sealed vessel

If not dried thoroughly after washing, stainless steel and cork can trap moisture in seams or crevices, creating conditions for mold or bacterial biofilm. This is a maintenance issue, not a material hazard, and is preventable with proper air-drying.

Possible

Cork degradation releasing particles

Cork is a natural material subject to crumbling or shedding if repeatedly exposed to temperature extremes or mechanical stress. Loose cork particles are not toxic but are undesirable in beverages; inspect regularly.

What we don’t know

This grade is a model-based estimate from public materials, coatings, and brand disclosure at 78% 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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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.