Thermos Review, Is Thermos Non-Toxic?
Thermos averages 77 out of 100 on PFAS Authority's PFAS and toxin screen across the 23 Thermos products graded as of October 2026, and all 23 reach its 70 point pass mark.
Thermos grades Excellent on our four-band scale. On disclosure, the brand says nothing publicly about PFAS. See what every brand has published about PFAS for how that compares.
PFAS Authority is a scoring system, not a laboratory. We do not test products ourselves. Grades are model-based, built from published ingredients, materials, certifications, brand disclosures and third-party lab results where they exist. See the rubric.
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Top-graded picks in the categories readers replace first, every one scored on the same rubric.
- polypropylene filter housing, carbon/sediment cartridge
- We found no PFAS statement from the brand
- Bacterial growth in spent cartridges
3 hazards checked on this product, all on its full breakdown.
Aquasure
Premier Series 75 GPD Under Sink Reverse Osmosis Water Filtration System
- RO membrane, carbon filters, stainless steel housing
- We found no PFAS statement from the brand
- Bacterial and microbial growth in housing and filters
4 hazards checked on this product, all on its full breakdown.
Avocado
Vegan Mattress
- organic cotton, natural latex, coconut coir, recycled steel coils
- The brand calls it PFAS-free, which we have not verified
- Heavy metals
2 hazards checked on this product, all on its full breakdown.
Does Thermos have PFAS, by category
Which Thermos products are PFAS-free? Good or better, best-graded first
- stainless steel exterior, vacuum insulation, stainless steel interior
- We found no PFAS statement from the brand
- Nickel leaching from stainless steel, 18/8 stainless steel does contain nickel (up to 8%). Under normal use…
3 hazards checked on this product, all on its full breakdown.
- Stainless steel (uncoated)
- We found no PFAS statement from the brand
- Bacterial growth in storage. If stored wet or with residual liquid for extended periods, stainless steel can…
- stainless steel, no stated coating
- We found no PFAS statement from the brand
- Seam or lid leachables. The lid may contain polymer components (silicone gaskets, plastic valve mechanisms)…
2 hazards checked on this product, all on its full breakdown.
- stainless steel interior, plastic exterior
- We found no PFAS statement from the brand
- Plastic exterior degradation and leachates. The exterior plastic shell contacts only air and hands, not…
3 hazards checked on this product, all on its full breakdown.
- stainless steel, no stated interior coating
- We found no PFAS statement from the brand
- Seal degradation and bacterial growth. The rubber gasket or silicone seal can degrade after 3-5 years of…
2 hazards checked on this product, all on its full breakdown.
- Stainless steel interior, BPA-free plastic exterior
- We found no PFAS statement from the brand
- Plastic exterior degradation and microplastic shedding. The outer plastic shell can crack, peel, or degrade…
2 hazards checked on this product, all on its full breakdown.
- Stainless steel body, plastic liner seal
- We found no PFAS statement from the brand
- Plastic seal degradation and microplastic shedding. If the plastic seal is heated repeatedly or exposed to…
2 hazards checked on this product, all on its full breakdown.
- stainless steel body, uncoated interior
- We found no PFAS statement from the brand
- Nickel leaching from stainless steel, 300-series stainless steel contains 8-12% nickel. Under prolonged…
2 hazards checked on this product, all on its full breakdown.
- Stainless steel interior and exterior, plastic lid
- We found no PFAS statement from the brand
- Plastic lid polymer degradation. Repeated dishwasher cycles or exposure to very hot liquids can degrade the…
3 hazards checked on this product, all on its full breakdown.
- stainless steel, vacuum-sealed, no coating
- We found no PFAS statement from the brand
- Stainless steel corrosion and nickel leaching. Food-grade stainless steel (304/18-8) leaches negligible…
2 hazards checked on this product, all on its full breakdown.
- Stainless steel interior, plastic exterior lid
- We found no PFAS statement from the brand
- Plastic lid degradation and leaching. The plastic lid and silicone gasket can degrade over years of repeated…
- Stainless steel body, plastic lid and seals
- We found no PFAS statement from the brand
- BPA & bisphenols. Plastic lid and gasket materials are not certified BPA-free by the brand. Standard…
4 hazards checked on this product, all on its full breakdown.
- Stainless steel exterior, vacuum-insulated, minimal internal coating
- We found no PFAS statement from the brand
- Silicone lid and gasket degradation. Silicone seals can accumulate mold, mildew, or bacterial biofilm if not…
2 hazards checked on this product, all on its full breakdown.
- Stainless steel tumbler with plastic slide lock lid
- We found no PFAS statement from the brand
- Plastic lid degradation. Polypropylene or acetal lids can develop micro-cracks and surface crazing over 2-4…
2 hazards checked on this product, all on its full breakdown.
- Stainless steel body, plastic/silicone lid
- We found no PFAS statement from the brand
- BPA & bisphenols. Thermos does not publicly confirm the lid polymer type or state whether it contains BPA…
2 hazards checked on this product, all on its full breakdown.
- Stainless steel and double-wall insulation
- We found no PFAS statement from the brand
- Seal/gasket degradation. Double-wall tumblers often use silicone or rubber gaskets; prolonged use and thermal…
2 hazards checked on this product, all on its full breakdown.
- Stainless steel interior, plastic/polymer exterior
- We found no PFAS statement from the brand
- Polymer exterior durability and degradation. Repeated thermal cycling and dishwasher exposure can cause…
2 hazards checked on this product, all on its full breakdown.
- stainless steel, plastic, rubber gaskets
- We found no PFAS statement from the brand
- Microplastics. If plastic compartments are filled with hot liquids or heated foods well above 60C (140F)…
2 hazards checked on this product, all on its full breakdown.
- Stainless steel interior, foam insulation outer shell
- We found no PFAS statement from the brand
- Foam insulation degradation. Polyurethane and polystyrene foams can break down over years of use, especially…
3 hazards checked on this product, all on its full breakdown.
- Stainless steel interior and exterior
- We found no PFAS statement from the brand
- Stainless steel corrosion and pitting. While rare, aggressive acids or prolonged salt water contact can…
2 hazards checked on this product, all on its full breakdown.
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- polyethylene foam insulation, plastic exterior, fabric lining
- We found no PFAS statement from the brand
- Microplastic shedding from degraded foam or plastic. Polyethylene foam can degrade into microparticles if…
3 hazards checked on this product, all on its full breakdown.
- plastic exterior, foam insulation, metal/plastic lining
- We found no PFAS statement from the brand
- BPA & bisphenols. The interior plastic lining material type and manufacturing standard are not disclosed by…
4 hazards checked on this product, all on its full breakdown.
- polyester, nylon, foam insulation
- We found no PFAS statement from the brand
- Formaldehyde / VOCs. Polyester fabric may be finished with formaldehyde-based resins for wrinkle or water…
4 hazards checked on this product, all on its full breakdown.
What to buy instead Good or better, in the categories Thermos sells
- stainless steel exterior, ceramic lining interior
- Ceramic coating degradation over time
3 hazards checked on this product, all on its full breakdown.
- Stainless steel body, plastic lid
- We found no PFAS statement from the brand
- Plastic lid polymer identity and leaching potential
3 hazards checked on this product, all on its full breakdown.
- Stainless steel body, no interior coating disclosed
- Silicone and plastic lid/valve leachables
3 hazards checked on this product, all on its full breakdown.
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, all on its full breakdown.
- borosilicate glass
- We found no PFAS statement from the brand
- Leaching from glass matrix or lid seals
2 hazards checked on this product, all on its full breakdown.
- Stainless steel container, no surface treatment
- Lid/gasket polymer leaching
3 hazards checked on this product, all on its full breakdown.
- Stainless steel bottle, stainless steel cap
- The brand calls it PFAS-free, which we have not verified
- Powder-coat cap degradation over time
3 hazards checked on this product, all on its full breakdown.
- Stainless steel body, powder-coat finish
- The brand calls it PFAS-free, which we have not verified
- Powder-coat finish degradation
3 hazards checked on this product, all on its full breakdown.
- Stainless steel bottle, plastic cap and silicone gasket
- The brand calls it PFAS-free, which we have not verified
- Silicone gasket degradation and leaching
3 hazards checked on this product, all on its full breakdown.
Thermos and PFAS, common questions
- Does Thermos have PFAS?
- Thermos averages 77 out of 100 on PFAS Authority's PFAS and toxin screen across the 23 Thermos products graded as of October 2026, and all 23 reach its 70 point pass mark. Grades are model-based estimates built from published materials, ingredients and disclosures, not lab tests.
- Is Thermos non-toxic?
- Thermos 18 oz. Icon Vacuum Insulated Stainless Steel Mug is the highest-graded Thermos product we have scored, at 80/100. It depends on the product line rather than the brand, so check the grade of the exact item you are buying.
- Which Thermos products are lower concern for PFAS?
- The highest-graded Thermos products we have scored are Thermos 18 oz. Icon Vacuum Insulated Stainless Steel Mug, Thermos Guardian Stainless Steel Mug, Thermos Stainless Steel Mug. That is our model-based estimate from materials and public disclosure, not a lab test.
Every grade uses the same public rubric. How grades work →