Klean Kanteen · Insulated Travel Drinkware
Klean Kanteen TKWide Twist Cap Bottle
Lower concern. Stainless steel bottle with no known PFAS coatings.
Klean Kanteen's stainless steel bottles are inherently PFAS-free. Plastic cap presents minor uncertainty, but no evidence of PFAS-containing treatments.
Shop Klean Kanteen on Amazon →Material
Stainless steel body, plastic cap
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.
The full breakdown
What it's made of and why it matters
The TKWide Twist Cap uses food-grade stainless steel (typically 18/8 or 304 grade) for the main bottle body, which is chemically inert and does not leach metals or degrade under normal use. The plastic cap is manufactured from polypropylene (PP) or similar food-contact polymers; Klean Kanteen has stated use of BPA-free plastics in their closures. Stainless steel avoids the aluminum leaching risk present in aluminum bottles and the Teflon-type coating fume hazard of non-stick coated cookware, making it one of the safest bottle material choices.
The brand's record and disclosure
Klean Kanteen has built its market position explicitly around non-toxic, sustainable materials and markets itself as a safer alternative to plastic water bottles. The company does not disclose detailed material certifications or third-party testing results publicly, which is typical for reusable bottle manufacturers but limits independent verification. No significant safety recalls or contamination incidents are on record for this product line. The brand's stance on PFAS is indirect; they market PFAS-free positioning without formal certification but have not issued public statements about intentional PFAS avoidance.
How it compares in its category
Stainless steel reusable bottles are among the safest options for water storage, avoiding leaching hazards of plastic, coating degradation of aluminum, and off-gassing of coated steel. Klean Kanteen competes directly with Hydro Flask and S'well; all three use similar stainless steel construction and polypropylene caps. The TKWide design eliminates narrow-mouth models, reducing bacterial growth risk from water residue in hard-to-clean areas and making maintenance simpler than some competitors.
If you buy it
Hand-wash the cap and cap threads after each use to prevent mold or bacterial biofilm formation in the closure mechanism; do not assume the stainless steel body itself requires special care beyond routine rinsing. Stainless steel is safe at all typical drinking temperatures but avoid prolonged contact with acidic liquids (lemon water, vinegar) which may cause minor pitting over years of use. Replace the plastic cap if it becomes discolored, develops odor, or shows visible wear; caps are typically available as replacement parts. The bottle itself has no known wear-out triggers under normal use.
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 cap material migration
Polypropylene caps used in this product are not known to release BPA, phthalates, or other endocrine disruptors under normal drinking-temperature use. No reported incidents or test findings specific to Klean Kanteen caps.
Bacterial or mold growth in closure threads
The twist-cap design can trap water and organic matter in the threads if not dried thoroughly after washing. This is a hygiene concern rather than a material hazard and is mitigated by regular hand-washing and air-drying of the cap.
Metal leaching from stainless steel
Food-grade stainless steel (304/18-8) does not leach chromium, nickel, or iron at pH levels of drinking water under normal storage conditions. Stainless steel is FDA-approved for food and beverage contact.
Off-gassing or volatile organic compounds
Stainless steel and polypropylene do not off-gas formaldehyde, siloxanes, or other VOCs at room temperature. This product does not involve coatings, linings, or adhesives known to release volatiles.
Degradation of cap seal or gasket integrity
Polypropylene caps can lose flexibility or develop cracks over 1-2 years of daily use, potentially allowing water leakage or entry of dust and microbes. This is a functional degradation rather than a toxicological hazard but indicates when replacement is prudent.
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.
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.