Bento Box Co · Food Storage Containers
S'well Bento Box
Lower concern for PFAS; typical bento material without obvious red flags, but verify compartment lids if silicone.
S'well's Bento Box uses stainless steel with polypropylene compartments, materials not inherently associated with PFAS. The brand does not publicly claim PFAS-free status or disclose PFAS testing.
Shop Bento Box Co on Amazon →Material
Stainless steel and plastic/polypropylene compartments
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
food packaging is a category where PFAS exposure is more common.
The full breakdown
What it's made of and why it matters
The S'well Bento Box uses food-grade stainless steel for the main container, which is chemically inert and does not leach metals under normal food storage conditions. The plastic compartments are polypropylene (PP, plastic #5), a relatively stable thermoplastic that does not contain BPA or phthalates by design. Polypropylene is considered low-risk for food contact because it has a higher melting point (around 130C) than lower-grade plastics and is less prone to leaching when used at typical refrigerator and room temperatures.
The brand's record and disclosure
Public safety information about Bento Box Co is limited; the brand does not appear to have a prominent third-party safety certification (e.g., NSF, FDA pre-approval statement) prominently advertised. No significant product recalls or safety controversies have been reported for this product line in the public domain. The brand's silence on PFAS is not unusual for consumer food storage brands, though proactive disclosure would be a plus; absence of disclosure does not indicate presence of PFAS in this stainless steel and polypropylene design.
How it compares in its category
Stainless steel bento boxes are among the lower-risk options in the food storage category compared to ceramic-coated glass (which can have lead in glazes) or bamboo composites (which may use formaldehyde binders). Polypropylene compartments are a standard, safe choice for multi-compartment lunch containers and are less concerning than PVC or polycarbonate alternatives. The combination places this product solidly in the mainstream safe tier for reusable food storage.
If you buy it
Do not microwave the plastic compartments; use the container only for cold or room-temperature foods unless manufacturer documentation explicitly permits microwave use. Hand wash in warm soapy water rather than high-heat dishwasher cycles to extend the life of seals and plastic components. Replace compartment gaskets or lids if they become visibly cracked, cloudy, or do not seal properly, as degradation can allow food residue retention. Stainless steel itself is durable and does not require special maintenance beyond normal cleaning.
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.”
Polypropylene leaching (general plastic risk)
Polypropylene is stable at room temperature and refrigeration but may leach trace compounds if exposed to high heat, prolonged sunlight, or harsh detergents. Normal cold-storage use poses minimal risk, but microwaving or boiling should be avoided.
Silicone gasket or seal degradation
If compartment lids use silicone seals, prolonged exposure to heat, UV, or oils can cause deterioration, potentially releasing siloxanes. Monitor seals visually and replace lids if degradation is evident.
Stainless steel nickel content (contact dermatitis risk)
Food-grade stainless steel (typically 300-series) contains 8-12% nickel; leaching into food is negligible under normal use. Nickel-sensitive individuals should be aware of cutlery contact rather than storage container contact, but this is not a documented concern for bento boxes.
Bacterial growth in seams or compartments
Multi-compartment designs can trap food debris in seams or gasket grooves if not cleaned thoroughly. Ensure full disassembly and drying after each use to prevent mold or bacterial colonization.
BPA or phthalate contamination in polypropylene
Polypropylene is inherently free of BPA and phthalates by polymer composition; no evidence of contamination has been reported for this product or typical PP food containers.
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.
Safer alternatives in Food Storage Containers
Caraway
Food Storage Set
Glass containers with plastic lids
Lower concern; glass + plastic lids with stated PFAS-free position, but no third-party verification of lid material.
⚠Risky category by default
Caraway
Home 9-Piece Mini Food Storage Set
Borosilicate glass containers with plastic lids
Lower-concern option; glass containers avoid PFAS coatings, but verify lid material before purchase.
⚠Risky category by default
Caraway
Cream 6.6-Cup Non-Stick Glass Food Storage Container with Lid
borosilicate glass with non-PFAS lid
Lower PFAS concern, glass container with stated non-PFAS lid, though third-party verification absent.
⚠Risky category by default
More food storage containers 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.