Mira · Portable Water Filtration Bottles
Mira Double Vacuum Insulated Stainless Steel Water Bottle
Lower concern. Bare stainless steel has no typical PFAS use.
Mira water bottles are double-wall stainless steel with no reported coatings or PFAS-containing treatments. No brand disclosure on PFAS, but bare stainless steel is inherently lower risk.
Shop Mira on Amazon →Material
stainless steel (bare, no known coatings)
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.
No PFAS disclosure
No public statement about PFAS in this product.
The full breakdown
What it's made of and why it matters
The Mira Double Vacuum Insulated bottle is constructed from food-grade stainless steel (typically 18/8 or 304-grade), with a vacuum layer between inner and outer walls for insulation. Stainless steel is chemically inert in normal use and does not leach metals into water at room temperature or even with hot beverages. The lack of interior coatings, liners, or plastic components in contact with the liquid significantly reduces leaching risk compared to coated metal or plastic bottles.
The brand's record and disclosure
Mira is a smaller reusable bottle brand with limited formal safety certifications or published testing data in public records. The brand does not appear to have issued recalls or faced documented safety controversies related to this product line. No specific PFAS or material safety statements are available from the manufacturer, though the stainless steel construction inherently avoids common coatings that would contain PFAS or other surface hazards.
How it compares in its category
Reusable stainless steel bottles like this one occupy the lower-hazard end of the water bottle spectrum compared to plastic bottles (BPA/phthalate leach risk) or insulated bottles with polymer liners and coatings. Metal vacuum bottles from established brands (Hydro Flask, S'well) follow similar material standards; Mira's product is functionally equivalent but with less third-party testing visibility. This is a commodity category with minimal brand differentiation in safety profile.
If you buy it
Hand wash or use warm (not boiling) dishwasher cycles to avoid damaging the vacuum seal or lid seals over time. Inspect the interior periodically for corrosion or white scale deposits (mineral buildup), which are normal and removable with dilute vinegar. Replace the bottle if the exterior shows dents that compromise the vacuum layer, or if the seal no longer keeps liquids hot/cold. The silicone gaskets and plastic cap components should be checked annually for wear; these are the only parts that may degrade or harbor bacteria if not dried completely.
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 corrosion or leaching under extreme conditions
Food-grade stainless steel (304/18-8) does not leach chromium or nickel into water at normal pH and temperature. Corrosion is only a concern if the bottle is stored with acidic liquids for extended periods or if the steel is damaged; no documented incidents for this product exist.
Silicone gasket and plastic lid degradation
The silicone seals and plastic cap components (likely polypropylene or similar) can degrade, crack, or harbor bacteria if not cleaned thoroughly after use. This is a mechanical wear issue rather than a chemical leaching hazard, but poor maintenance can allow mold or residue buildup in the seal grooves.
Bacterial growth in the vacuum layer or lid seals
If the bottle is not fully dried after washing or is left with liquid residue inside for extended periods, the moist environment in the vacuum chamber or around seals can support bacterial growth. This is a hygiene issue rather than a manufacturing defect; regular thorough drying mitigates the risk.
Coating or liner leachables (if present)
The Mira Double Vacuum bottle does not appear to have an interior polymer coating or epoxy liner based on standard vacuum bottle construction. If any interior coating is present, it is not documented; bare stainless steel contact is the presumed design.
Thermal shock or vacuum seal failure
Rapid temperature changes (e.g., hot liquid followed immediately by freezing) can theoretically stress the vacuum seal, but this is a durability issue not a chemical safety hazard. No chemical leaching occurs from seal failure itself.
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.
More portable water filtration bottles 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.