Ello · Insulated Drinkware Tumblers
Ello Leakproof Oasis Go+ Tumbler
Plastic tumbler with no disclosed PFAS info. Moderate concern for water-repellent coating coatings.
Ello does not disclose PFAS use or testing for this leakproof tumbler. Double-wall plastics and waterproof seals may contain PFAS; no third-party verification available.
The safe swap
Contigo
Contigo Byron 2.0 Stainless Steel Travel Mug Snapseal
95/100 safety
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Double-wall plastic tumbler with leakproof seal and thermal insulation
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
Waterproof / stain-resistant treatment
water-repellent coating treatments have historically used PFAS.
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 Ello Oasis Go+ is constructed from double-wall plastic (likely polypropylene or copolyester blend) with a leakproof silicone or thermoplastic rubber seal. The thermal insulation between walls traps air and requires a sealed structure, which can involve polymer coatings or surface treatments to achieve water resistance. The leakproof mechanism depends on the seal material's durability and the structural integrity of the plastic walls under temperature cycling.
The brand's record and disclosure
Ello (part of the larger housewares ecosystem) does not publicly disclose PFAS content or water-repellent coating composition for this product line, a gap that has become a marker of transparency in the reusable drinkware category. No major product recalls or safety violations have been published by the CPSC or FDA for this specific model. The brand has not pursued third-party certifications (e.g., NSF, BPA-free seals) that would signal proactive testing beyond baseline regulatory compliance.
How it compares in its category
Reusable plastic tumblers vary widely in their coating strategies; some competitors explicitly certify BPA/BPS/phthalate-free status or avoid water-repellent coating treatments altogether. The Ello Oasis Go+ sits in the mid-market segment where thermal performance is prioritized and material transparency is minimal. Stainless-steel or glass alternatives avoid plastic-leaching risks entirely but trade off the insulation benefits and durability of this design.
If you buy it
Do not fill with liquids hotter than 140-150 F (check manual), as sustained heat can accelerate plastic degradation and any coating leaching. Wash by hand with mild soap; dishwashers can degrade seals and coatings faster. Inspect the seal and inner walls annually for cloudiness, cracks, or odor changes, which signal material breakdown. Replace every 2-3 years if used daily, or sooner if the seal loosens or coating shows wear.
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.”
BPA/BPS or phthalate leaching from plastic base
Ello does not disclose the specific plastic formulation or additives. While modern polypropylene tumbler bases are often BPA-free, older molds or imported batches may contain legacy bisphenol compounds. Risk increases with hot-liquid contact and repeated heating cycles.
Coating degradation and leaching from water-repellent coating or adhesion layers
Double-wall tumblers often require a thin waterproof or bonding coating between walls; without disclosure, the composition is unknown. Coatings can flake or leach under thermal stress, potentially introducing trace compounds into beverages or the environment.
Silicone or rubber seal degradation
The leakproof seal is typically food-grade silicone, but prolonged contact with hot liquids, alcohol, or acidic drinks (coffee, citrus) can cause swelling, hardening, or breakdown. Degraded seals may harbor bacteria or fail to prevent leaks.
Microplastic shedding from wear and tear
Repeated dishwashing, thermal cycling, and contact with utensils or ice can cause microscopic plastic fragments to flake from the tumbler interior or seal. The risk is low but non-zero in any long-lived plastic drinkware product.
Mold or bacterial growth in seal channel
Leakproof seals create narrow crevices that are difficult to dry completely and may trap residual liquid. Poor drying or storage in humid conditions can promote mold or bacterial colonization, particularly if the product sits unused for weeks.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 62% 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 Insulated Drinkware Tumblers
Contigo
Byron 2.0 Stainless Steel Travel Mug Snapseal
Stainless steel, silicone gasket
Travel mug with lower PFAS concern; stainless steel typically safe.
✓Bare metal or glass, no coating at all
Thermos
Stainless King Travel Tumbler
Stainless steel exterior, vacuum-insulated, minimal internal coating
Lower concern. Stainless steel tumbler with standard design, no PFAS-prone features.
✓Bare metal or glass, no coating at all
Thermos
Stainless Steel Tumbler w/ Slide Lock Lid
Stainless steel tumbler with plastic slide lock lid
Lower concern. Stainless steel is PFAS-free; monitor lid material.
✓Bare metal or glass, no coating at all
More insulated drinkware tumblers 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.