S'well Kitchen | S'well Light Pink Stainless Steel Insulated Bento Lunch Box | Color: Gray/Pink | Size: Os
Skip until brand discloses gasket/seal composition and PFAS intent.
S'well bento boxes use stainless steel bodies, lower concern inherently. Silicone gaskets are typical but brand discloses nothing about PFAS or any applied water-repellent coatings on seals.
We flunk more products than we pass. This one earned its grade. How we grade
Material
stainless steel body, silicone gasket
Lab data
No public lab test
What S'well Kitchen | S'well Light Pink is made of, ingredients and materials
The S'well bento box uses a stainless steel body, which is chemically inert and does not leach metals or contaminants into food under normal use. The critical unknown component is the silicone gasket sealing the lid, whose specific formulation and additives S'well has not publicly disclosed. Silicone itself is generally regarded as food-safe, but gasket quality, colorant sources, and whether processing aids or plasticizers remain in the material are not specified here.
What’s concerning
Category baseline
The starting point for this type of product, before anything specific to this product is counted.
No PFAS disclosure
No public statement from the brand about PFAS in this product.
Silicone gasket composition and additives
The gasket material is not publicly specified by S'well. While food-grade silicone is commonly used, undisclosed colorants, processing aids, or residual oligomers could migrate into food under heat or with acidic/fatty foods; migration risk is low but cannot be assessed without formulation disclosure.
Seal degradation and bacterial growth
If the silicone gasket is not cleaned thoroughly or dried after use, moisture and food residue can accumulate, promoting mold, algae, or bacterial colonization in the seal pocket. This is a use-related hygiene issue, not a material defect, but is a practical concern for lunch box storage between meals.
PFAS
S'well has not disclosed whether the silicone gasket or any other seal component contains PFAS-based water or oil repellents. Some silicone gasket formulations may include fluorinated additives for hydrophobic properties. This is graded separately but creates ambiguity on actual product safety until the brand provides formulation data.
Source, ATSDR ↗What’s reassuring
Base material not linked to PFAS
The main material recorded for this product is not one associated with PFAS.
Microplastic or silicone particle shedding
No documented incidents of silicone degradation or particle release from S'well bento gaskets are on record. Stainless steel does not fragment. Risk remains low if the gasket is maintained and replaced if visibly worn.
Metal leaching from stainless steel body
Stainless steel is chemically stable in contact with food and does not leach nickel, chromium, or other metals under normal storage and use conditions. Risk is minimal unless the steel is deliberately abraded or exposed to prolonged high temperatures well above food storage ranges.
The full breakdown
The brand's record and disclosure
S'well does not appear to have published detailed material safety data sheets, PFAS declarations, or third-party certifications (such as NSF or FDA compliance statements) for this product. The brand has maintained silence on gasket and seal composition and PFAS intent across its product lines. No recalls or documented safety complaints specific to this bento box model are on record in public databases.
How it compares in its category
Stainless steel lunch containers are among the lower-hazard choices in food storage, as steel itself does not leach. Competitors like Klean Kanteen, Hydro Flask, and some glass-lined alternatives often disclose gasket materials and manufacturing standards more transparently. Many mid-range lunch boxes still rely on polypropylene or other plastics with undisclosed additives, making stainless steel a material advantage here, but brand transparency lags peers.
If you buy it
Hand wash the gasket and interior after each use to prevent residual food and moisture from degrading silicone over time or promoting microbial growth. Do not place the sealed box in a dishwasher or expose it to temperatures above 140F (60C), as silicone can soften and reduce seal integrity. Inspect the gasket annually for visible cracks, cloudiness, or odor changes; replace it if the seal no longer holds or the silicone becomes sticky or brittle. Avoid storing acidic foods (vinegar, citrus) or strong-smelling items for extended periods, as silicone can absorb odors and may transfer them to subsequent foods.
What we don’t know
- Basis
- Model estimate, 72% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- S'well has made a specific claim
Formulations change between production runs, so check the current label. How we grade.
Better-graded alternatives in Lunch Boxes
Klean Kanteen
Double Wall Vacuum Insulated Stainless Steel Food Canister Container with Leak Proof Lid
- Stainless steel body, silicone gasket lid seal
- The brand calls it PFAS-free, which we have not verified
- Silicone gasket degradation
3 hazards checked on this product. See all of them.
Snapware
Meal Box Glass
- borosilicate glass
- We found no PFAS statement from the brand
- Leaching from glass matrix or lid seals
2 hazards checked on this product. See all of them.
OXO
Steel Pop Big Square Short - 2.8 Qt/2.6 l
- Stainless steel container, no surface treatment
- Lid/gasket polymer leaching
3 hazards checked on this product. See all of them.
More lunch boxes 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.