Hydro Flask Review, Is Hydro Flask Non-Toxic?
Hydro Flask averages 75 out of 100 on PFAS Authority's PFAS and toxin screen across the 31 Hydro Flask products graded as of October 2026, and 28 of them reach its 70 point pass mark.
Hydro Flask grades Excellent on our four-band scale.
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.
What Hydro Flask says and does about PFAS
Hydro Flask does not publish a PFAS policy that we could find. In February 2024, during the controversy over lead in other brands’ tumblers, Cycling Weekly reported that Hydro Flask had said its bottles contain no lead, BPA, phthalates, heavy metals or PFAS. We could not locate that statement on Hydro Flask’s own channels, and we found no independent lab test of its products for PFAS.
- Brand statementCycling Weekly reported in February 2024 that Hydro Flask had released a statement saying its bottles contain no lead, BPA, phthalates, heavy metals or PFAS. Cycling Weekly ↗
- Brand statementHydro Flask’s own post that same week, as quoted by Gizmodo, said it had not used lead in its sealing process for over a decade, and did not mention PFAS. Gizmodo ↗
Sources checked September 14, 2026. A brand statement is the company’s own claim, which we report but have not verified. Our grades are model-based estimates, not lab tests.
Hydro Flask is one of the brands we researched by hand for our record of what every brand has published about PFAS, where the same question is answered for each of them in one line.
Does Hydro Flask have PFAS, by category
Worth buying from Hydro Flask Good or better, best-graded first
Hydro Flask
32 oz Lightweight Flex Straw Bottle
- Stainless steel bottle; silicone straw
- Silicone straw degradation and microbial growth, Silicone is not prone to chemical leaching but can absorb…
2 hazards checked on this product. See all of them.
Hydro Flask
Micro Hydro Mini Bottle
- Stainless steel vacuum-insulated double wall
- Silicone/TPE gasket degradation, Cap seals and closure gaskets can degrade or harbor mold growth if not…
3 hazards checked on this product. See all of them.
Hydro Flask
Epic Water Filters The Answer 2.0 Hydro Flask Water Filter
- Activated carbon filter cartridge, stainless steel housing
- Bacterial growth in filter cartridge, Activated carbon filters become a growth medium for bacteria if not…
3 hazards checked on this product. See all of them.
Hydro Flask
24oz Standard Flex Straw Cap
- Stainless steel bottle, silicone straw cap
- Silicone degradation over time, Food-grade silicone is stable at normal temperatures but may degrade or…
2 hazards checked on this product. See all of them.
Hydro Flask
24oz Wide Mouth Flex Straw Cap
- Stainless steel bottle; polymer cap and straw
- Polymer cap/straw composition opacity, Hydro Flask does not publicly certify that caps and straws are free of…
4 hazards checked on this product. See all of them.
Hydro Flask
32 oz Wide Mouth Travel Bottle with Flex Straw Cap in Harbor Blue
- Stainless steel body and cap; flex straw likely polypropylene or silicone
- Flex straw material leaching (composition unconfirmed), Hydro Flask does not publicly specify whether the…
3 hazards checked on this product. See all of them.
Hydro Flask
32 oz Wide Mouth Water Bottle
- Stainless steel body, plastic lid (unspecified polymer)
- BPA & bisphenols, Hydro Flask does not publicly specify the lid polymer type or confirm BPA/BPS absence.…
3 hazards checked on this product. See all of them.
Hydro Flask
24 oz Wide Mouth Flex Straw Cap
- stainless steel bottle, silicone/rubber straw cap
- Silicone/rubber degradation and leaching, Silicone caps can degrade with repeated heat exposure (hot water…
2 hazards checked on this product. See all of them.
Hydro Flask
Bottle Standard Mouth
- Stainless steel body, rubber/plastic components
- PFAS, Hydro Flask does not disclose whether gaskets or seals contain Teflon-type coating, FEP, or other…
3 hazards checked on this product. See all of them.
Hydro Flask
Wide Mouth Flex Straw Bottle
- stainless steel insulation, silicone flex straw, polypropylene lid
- Bacterial and mold growth in straw/seal crevices, Silicone straws and threaded lid seams are known to trap…
2 hazards checked on this product. See all of them.
Hydro Flask
20-Ounce All Around Tumbler
- stainless steel interior, vacuum-insulated
- Lid/gasket material degradation, The lid often contains silicone or plastic gaskets; extended UV exposure or…
Hydro Flask
Wide Mouth Cap Bottle
- stainless steel bottle with plastic cap
- Plastic cap degradation and leachables, Polypropylene caps can degrade with repeated hot liquid exposure…
3 hazards checked on this product. See all of them.
Hydro Flask
All Around Travel Tumbler
- Stainless steel with vacuum insulation
- Microplastic shedding from cap or seals, If the lid is plastic or contains plastic components, wear or…
2 hazards checked on this product. See all of them.
Hydro Flask
20 oz All Around Tumbler
- Stainless steel with vacuum insulation
- Silicone gasket degradation, Silicone gaskets are generally food-safe but can degrade if exposed to prolonged…
Hydro Flask
32 oz Hydro Flask All Around Travel Tumbler
- Stainless steel body, plastic lid, rubber gasket
- Rubber gasket degradation and contaminant shedding, Repeated thermal cycling and acidic beverages can degrade…
2 hazards checked on this product. See all of them.
Hydro Flask
32 oz Travel Tumbler
- Double-wall stainless steel, proprietary lid gasket
- Silicone gasket degradation and bacterial growth, The proprietary lid gasket is not replaceable by the…
2 hazards checked on this product. See all of them.
Hydro Flask
40 oz Lightweight Flex Cap Bottle
- Tritan copolyester (cap), stainless steel/plastic body
- Tritan cap material degradation, Tritan is durable but repeated high-temperature washing or exposure to…
2 hazards checked on this product. See all of them.
Hydro Flask
12 oz Outdoor Tumbler
- Stainless steel wall construction with foam insulation
- Coating degradation and foam exposure, If the seal between stainless steel walls fails due to impact or…
Hydro Flask
24 oz Travel Tumbler
- Stainless steel double-wall insulation, no interior coating disclosed
- Lid seal degradation and bacterial growth, The silicone or rubber gasket in the lid may degrade or trap…
Hydro Flask
40 oz Wide Mouth Flex Straw Cap
- Stainless steel (container), silicone/thermoplastic (flex straw cap)
- Silicone degradation and bacterial colonization, Silicone seals and straw can trap moisture and harbor…
2 hazards checked on this product. See all of them.
Hydro Flask
All Around Travel Tumbler
- Stainless steel with powder-coated exterior
- Powder-coat degradation, The exterior powder coating can chip or peel if dropped or banged repeatedly…
2 hazards checked on this product. See all of them.
Hydro Flask
All Around Tumbler
- Stainless steel exterior, vacuum insulation, plastic/polymeric lid
- Polymer lid leaching and microplastic, The polymeric lid may shed microplastics if degraded by heat…
2 hazards checked on this product. See all of them.
Hydro Flask
All Around Tumbler Straw Lid
- Stainless steel tumbler, plastic/silicone lid
- BPA & bisphenols, Hydro Flask does not publicly disclose lid resin type or additives. Standard food-grade…
3 hazards checked on this product. See all of them.
Hydro Flask
Carry Out Lunch Box
- stainless steel exterior, plastic/polypropylene interior
- Bacterial or mold growth in seals and gaskets, Insulated lunch boxes with multiple seals and compartments can…
2 hazards checked on this product. See all of them.
Hydro Flask
Carryout Lunch Rolltop
- Nylon fabric, polyester lining, plastic hardware
- Polyester microplastic shedding from lining, Polyester linings can shed fibers when abraded by ice packs…
2 hazards checked on this product. See all of them.
Hydro Flask
Travel Tumbler
- Stainless steel body with rubber base
- Coating degradation or peeling, If the tumbler interior has an enamel or proprietary coating (not standard in…
2 hazards checked on this product. See all of them.
Hydro Flask
Tumbler
- stainless steel with unspecified interior coating/lining
- Interior coating composition and migration, The interior coating material is not disclosed; if it contains…
3 hazards checked on this product. See all of them.
Hydro Flask
Kids Insulated Lunch Box
- stainless steel body, plastic lid and lining
- BPA & bisphenols, The plastic components (lid, interior lining) are not identified by published material name…
3 hazards checked on this product. See all of them.
Graded and flagged Poor and Bad, we’d swap these
Hydro Flask
Carryout Lunch Tote
- Recycled polyester exterior, waterproof-treated lining
- PFAS, Waterproof fabric finishes on insulated totes historically use C6 or C8 PFAS compounds. Hydro Flask…
4 hazards checked on this product. See all of them.
Hydro Flask
Insulated Lunch Bag
- neoprene-lined polyester exterior with waterproof backing
- PFAS, The neoprene and polyester materials are low-risk, but the waterproof backing likely uses either…
3 hazards checked on this product. See all of them.
Hydro Flask
Carryout Lunch Bag
- Nylon/polyester outer with unspecified water-resistant finish
- Phthalates, Polyester in the blend may contain residual phthalates from manufacturing; no third-party testing…
4 hazards checked on this product. See all of them.
What to buy instead Good or better, in the categories Hydro Flask sells
Aquamira
Water Storage Treatment 2 oz Glass Bottles 60 gallons Purification
- glass bottles, sodium dichloroisocyanurate treatment chemical
- We found no PFAS statement from the brand
- Chemical overdose or misuse
5 hazards checked on this product. See all of them.
Big Berkey
Empty Housing with NO Filters Included
- Stainless steel housing and spigot
- We found no PFAS statement from the brand
- Bacterial growth and biofilm if filters not replaced
5 hazards checked on this product. See all of them.
LifeStraw
Home Glass Water Filter Pitcher
- Borosilicate glass pitcher, replaceable activated-carbon filter cartridge
- Bacterial growth in filter cartridge if unmaintained
5 hazards checked on this product. See all of them.
Owala
FreeSip Sway Stainless Steel
- Stainless steel body, no interior coating disclosed
- Silicone and plastic lid/valve leachables
3 hazards checked on this product. See all of them.
Owala
Stainless Steel Straw Tumbler Route 66
- Stainless steel tumbler, bare uncoated
- Coating degradation and microplastic shedding from exterior print
3 hazards checked on this product. See all of them.
Thermos
18 oz. Icon Vacuum Insulated Stainless Steel Mug
- stainless steel exterior, vacuum insulation, stainless steel interior
- We found no PFAS statement from the brand
- Nickel leaching from stainless steel
3 hazards checked on this product. See all of them.
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.
Hydro Flask and PFAS, common questions
- Does Hydro Flask have PFAS?
- Hydro Flask averages 75 out of 100 on PFAS Authority's PFAS and toxin screen across the 31 Hydro Flask products graded as of October 2026, and 28 of them reach its 70 point pass mark. Grades are model-based estimates built from published materials, ingredients and disclosures, not lab tests. Hydro Flask was reported in February 2024 to have said its bottles contain no PFAS, but we could not find a PFAS policy or that statement on its own site.
- Is Hydro Flask non-toxic?
- Hydro Flask 32 oz Lightweight Flex Straw Bottle is the highest-graded Hydro Flask product we have scored, at 100/100. It depends on the product line rather than the brand, so check the grade of the exact item you are buying.
- Which Hydro Flask products are lower concern for PFAS?
- The highest-graded Hydro Flask products we have scored are Hydro Flask 32 oz Lightweight Flex Straw Bottle, Hydro Flask Micro Hydro Mini Bottle, Epic Water Filters The Answer 2.0 Hydro Flask Water Filter. That is our model-based estimate from materials and public disclosure, not a lab test.
- Which Hydro Flask products should I avoid?
- The lowest-graded Hydro Flask products we have scored are Hydro Flask Carryout Lunch Bag, Hydro Flask Insulated Lunch Bag, Hydro Flask Carryout Lunch Tote. Each one links to the evidence behind its grade.
Every grade uses the same public rubric. How grades work →