Corkcicle · Insulated Travel Mugs
Corkcicle Cold Cup XL
Lower concern. Stainless steel tumbler unlikely to contain PFAS.
Corkcicle Cold Cup XL uses stainless steel construction with no reported PFAS concerns. Brand does not disclose PFAS testing, but insulated metal tumblers typically carry lower risk than coated or treated products.
Shop Corkcicle on Amazon →Material
Double-wall insulated stainless steel
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).
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 Corkcicle Cold Cup XL uses food-grade 18/8 stainless steel (austenitic alloy with 18% chromium, 8% nickel) as its inner and outer walls, separated by an insulating air gap. This material is chemically inert in contact with food and beverages across normal temperature ranges and does not leach metallic ions into liquids under standard use. The stainless steel construction eliminates the coating-degradation and metallic-leaching risks present in ceramic, aluminum, or polymer-lined alternatives.
The brand's record and disclosure
Corkcicle does not publicly disclose detailed material sourcing or third-party certifications (BPA-free claims, NSF, or heavy metal testing) on product pages or marketing materials. The brand has no documented recalls, chemical controversies, or safety violations on public record. Absence of transparency is typical for mid-market drinkware brands but limits independent verification of supplier practices or material purity beyond the known safety of stainless steel itself.
How it compares in its category
Double-wall stainless steel tumblers are among the safest reusable drinkware options, with minimal chemical hazard profiles compared to plastic alternatives (BPA/BPS leaching risk) or ceramic-coated designs (glaze heavy metals, coating wear). Corkcicle's product sits in the mainstream premium segment; it offers no additional safety certifications or transparency that would distinguish it from competitors like Hydro Flask or Yeti, which also use 18/8 stainless construction without extensive public hazard disclosure.
If you buy it
Hand-wash or use the dishwasher on standard cycles; stainless steel tolerates both. Avoid prolonged contact with acidic beverages (lemon water, vinegar) on a daily basis, as chronic exposure can slightly accelerate microscopic surface oxidation, though this poses no health risk. Replace only if the outer coating (if powder-coated) chips to expose base metal, or if the double-wall seal fails (indicated by liquid between walls). The tumbler has no specified temperature limits but is designed for cold beverages; do not fill with boiling liquid as it may compromise the seal over time.
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.”
Stainless steel composition (nickel content)
18/8 stainless steel contains 8% nickel, which can leach in trace amounts in highly acidic liquids or prolonged storage. Risk is very low in normal use (occasional acidic drinks) and negligible for most consumers; only relevant for individuals with diagnosed nickel sensitivity or contact dermatitis.
Coating degradation and corrosion
The outer surface may have a powder-coat or anodized finish for aesthetics. No reports of coating failure or lead/cadmium contamination in Corkcicle products; stainless steel substrate beneath is non-toxic if exposed.
Double-wall seal integrity
If the seal between inner and outer walls fails, water may accumulate in the insulation gap, risking bacterial or mold growth if left undried. This is a durability issue rather than a chemical hazard; inspect annually for visible gaps or liquid presence.
Lid and gasket materials
Corkcicle lids typically use silicone gaskets or plastic snap components; no specific testing data is publicly available on whether these contain BPA, BPS, or phthalates. Standard food-grade silicone is assumed but not verified by third-party certification.
Bacterial colonization risk
Stainless steel is resistant to bacterial biofilm compared to plastic. No material-inherent risk; risk is operational only if the tumbler is left wet and undried for extended periods in warm conditions.
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.
Safer alternatives in Insulated Travel Mugs
Corkcicle
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More insulated travel mugs 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.