Zojirushi · Insulated Drinkware Tumblers
Stainless Steel Travel Mug Zojirushi
Lower PFAS concern, stainless steel core. Lid material unclear.
Zojirushi travel mugs use stainless steel construction, inherently lower PFAS risk. No brand PFAS claims found; plastic lid composition not disclosed.
Shop Zojirushi on Amazon →Material
stainless steel interior, plastic lid
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.
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
Zojirushi travel mugs use food-grade 18/8 stainless steel (304 or 316 grade) for the interior, which is chemically inert and does not leach metals into beverages under normal use. The lid and seals are plastic, likely polypropylene (PP) or similar, which are lower-risk polymers but warrant temperature management. The interior stainless steel construction is the primary safety advantage here, as it sidesteps the leaching concerns present in ceramic or aluminum-lined alternatives.
The brand's record and disclosure
Zojirushi is a Japanese manufacturer with a long history in thermal tableware and does not publicly disclose detailed material safety testing or third-party certifications on PFAS or other contaminants. The brand has not faced major food-contact recalls related to chemical contamination. Limited transparency on supply chain testing or material sourcing standards, but no established controversies in independent testing.
How it compares in its category
Stainless steel interiors are the safer choice compared to ceramic-lined, aluminum, or copper-lined travel mugs, which can leach metals under acidic conditions or with coating wear. Most plastic-lidded travel mugs present similar concerns around lid material and seal degradation. Zojirushi's thermal performance is industry-standard; safety profile sits in the middle-to-upper range due to stainless steel core, but lid opacity is a shared weakness across the category.
If you buy it
Hand-wash the lid and seals regularly to prevent bacterial biofilm accumulation in crevices; most plastic lids are not dishwasher-safe. Avoid filling with boiling water if the lid is sealed (pressure can degrade seals over time). Replace the lid gasket every 1-2 years if it becomes discolored, cracked, or loses its seal. Do not use for prolonged storage of acidic beverages (citrus, vinegar) beyond 24 hours, as even stainless can show minor pitting with repeated exposure.
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 seal degradation
Polypropylene and elastomer seals are not specified by Zojirushi in most product literature. Over time, repeated temperature cycling and contact with hot liquids can cause microscopic cracking or leaching of oligomers; specific migration data for this lid material is not publicly available.
Bacterial biofilm in lid threads and seals
Travel mug lids are well-documented as difficult-to-clean, and Zojirushi's design includes narrow threads and rubber gaskets where pathogens can colonize if not disassembled and dried completely after each use. Not unique to this brand but a category-wide risk.
Stainless steel nickel release
Food-grade 18/8 stainless steel (304) in contact with drinking water poses negligible nickel leaching under normal pH and temperature conditions. No recalls or testing reports suggest nickel migration from Zojirushi mugs; FDA regulations permit stainless steel for food contact without restrictions.
Coating or manufacturing residues on interior
Zojirushi does not apply interior coatings to its stainless steel models, reducing the risk of peeling enamel or ceramic residue. Standard manufacturing (pickling, passivation) leaves a passive oxide layer that is safe for beverage contact and does not off-gas or migrate.
Thermal shock cracking of double-wall seal
If the mug is filled with boiling water and then immediately exposed to freezing temperatures, the vacuum seal integrity between walls can degrade, compromising insulation but not directly creating a chemical hazard. No specific failure rates reported for Zojirushi models.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 82% 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.