Corkcicle · Insulated Travel Drinkware
Corkcicle Go Cup XL 30oz Mauve
Lower concern product, but verify lid seal material with brand.
Corkcicle Go Cup is primarily stainless steel, a PFAS-free core material. Brand makes no PFAS claims; plastic components and gasket coatings are not disclosed, creating minor uncertainty.
Shop Corkcicle on Amazon →Material
Stainless steel with plastic lid and gaskets
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 Go Cup XL uses 18/8 stainless steel for the main vessel, which is chemically inert and does not leach metals like aluminum or cadmium into beverages. The lid and internal gaskets are plastic components (material type not publicly specified by Corkcicle), which carry the primary material-safety question for this product. Stainless steel construction avoids the coating-degradation and Teflon-type coating off-gassing risks present in some insulated cookware, making it safer for repeated hot and cold use.
The brand's record and disclosure
Corkcicle has not published detailed material safety disclosures or third-party certifications (e.g., FDA food-contact verification, phthalate testing) on their website or marketing materials. The brand maintains silence on PFAS use in lid seals, which is a common industry gap for insulated drinkware manufacturers. No recalls, contamination incidents, or credible safety controversies have been established for this product line in publicly available records. This absence of transparency is typical for the drinkware category but does not indicate a known hazard.
How it compares in its category
Insulated stainless steel cups with plastic lids dominate the premium drinkware market; Corkcicle is a mid-to-upper-tier brand with similar material architecture to competitors like Hydro Flask and S'well. Unlike some budget alternatives, this product avoids coated interiors, which eliminates lead-in-glaze and Teflon-type coating concerns common in enameled cookware. The plastic lid design is a standard compromise in this category; most competitors do not disclose lid material or PFAS content either, making Corkcicle broadly representative rather than exceptional.
If you buy it
Do not fill with boiling water; stainless steel containers tolerate heat, but plastic lids and gaskets may off-gas volatile compounds if subjected to prolonged high temperatures (above 60C / 140F). Hand-wash the lid and gaskets separately to inspect for degradation, warping, or discoloration, and replace them every 1 to 2 years if visible wear appears. Avoid acidic beverages stored for extended periods, as even stainless steel can develop pitting under rare conditions with certain drink types. Request material composition of the lid from Corkcicle customer service if PFAS concern is a personal priority; their silence suggests they have not tested or committed to PFAS-free formulations.
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.”
Plastic lid and gasket material identity
Corkcicle does not publicly identify the plastic resin or additives in the lid or silicone gaskets. Lid plastics may contain BPA, phthalates, or PFAS depending on formulation; without material disclosure, this cannot be ruled out but is not confirmed either.
Off-gassing from plastic components at elevated temperature
Plastic lids and seals used in insulated drinkware can release volatile organic compounds (VOCs) if exposed to sustained heat above 60C. Risk is low with normal cold/room-temperature beverage use but increases if user routinely fills cup with very hot liquids.
Stainless steel leaching (minor concern)
18/8 stainless steel is food-contact-safe and does not leach nickel, chromium, or other metals into beverages under normal use. No established risk with this material grade in published testing.
Coating or enamel hazards
Stainless steel vessel has no glaze, enamel, or interior coating, eliminating lead, cadmium, and ceramic-leaching risks that occur in some insulated cookware.
Gasket degradation and bacterial growth
Silicone or rubber gaskets can degrade, harbor water residue, and support mold or bacterial growth if not cleaned thoroughly between uses. This is a maintenance issue, not an inherent material hazard, but requires user diligence.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 72% 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 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.