S'well · Insulated Travel Drinkware
S'well Traveler with Flip Straw Lid 16oz
Lower concern; stainless steel bottle with no known PFAS risks.
S'well bottles are primarily double-wall stainless steel, a PFAS-free material. The plastic lid and straw carry minor uncertainty, but no public evidence of PFAS treatment in S'well products.
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Double-wall stainless steel with plastic lid and straw
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 S'well Traveler's primary vessel is double-wall stainless steel (typically 18/8 or similar food-grade alloy), which does not leach metals into beverages under normal use and resists corrosion. The removable flip straw lid and straw are plastic (likely polypropylene or similar commodity resin), which is thermally stable at typical drinking temperatures but can degrade if exposed to very hot liquids or prolonged sunlight. The stainless steel construction avoids ceramic-glaze lead risks, Teflon-type coating nonstick hazards, and aluminum leaching that plague other drinkware.
The brand's record and disclosure
S'well has not published detailed material safety disclosures, third-party certifications (such as NSF or FDA compliance statements), or PFAS testing results on this product. The company maintains a general 'eco-friendly' marketing stance but does not transparently address chemical content of lids and straws. No major recalls or safety controversies have been established for this product line in public records, suggesting no acute hazard history.
How it compares in its category
Stainless steel drinkware is among the safest categories for reusable bottles; it avoids leaching risks common in coated aluminum or plastic-lined alternatives. The plastic lid and straw are a weak point compared to all-stainless or glass-topped competitors, but are standard across most insulated bottles at this price point. S'well occupies the mid-premium segment and is comparable in material hazard profile to Hydro Flask or Klean Kanteen, though less transparent on chemical testing.
If you buy it
Avoid filling with liquids above 60°C (140°F) to prevent plastic lid and straw degradation and potential microplastic shedding. Hand-wash or use a straw brush regularly to prevent bacterial biofilm growth inside the straw, a common issue with reusable straws. Replace the plastic lid or straw if cracking, cloudiness, or odor develops, as these are signs of material breakdown. The stainless steel vessel itself should last years; the plastic components are the consumable wear items.
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 straw thermal stability
Commodity plastic lids and straws can soften, leach, or shed microplastics if regularly exposed to hot beverages or direct sunlight. S'well does not disclose resin type or thermal limits, so risk is speculative but standard for this product category.
Stainless steel corrosion and ion leaching
Food-grade stainless steel (18/8) does not corrode or leach nickel, chromium, or iron into non-acidic beverages at room temperature under normal use. No documented leaching incidents for S'well bottles have been reported.
Bacterial or mold growth in straw and lid seams
Reusable straws and flip-lid designs can trap moisture and organic matter in hard-to-clean seams. This is a hygiene issue rather than a chemical hazard but is common to all reusable drinkware of this design.
Adhesive or coating on stainless steel seams
S'well does not disclose whether adhesives or gasket materials in the double-wall construction contain regulated chemicals such as BPA or formaldehyde releasers. Food contact surfaces are presumed food-grade, but lack of transparency limits certainty.
Fragrance or plasticizer migration from lid gaskets
Rubber or silicone gaskets in the flip lid may leach odor compounds or trace plasticizers into beverages, though this is rare with modern food-grade gaskets. No incidents have been documented for this product.
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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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.