100/ 100
A
OverallA92/100
32oz Stainless Bottle Cap and Straw

Clearly Filtered · Filtered Water Bottles

32oz Stainless Bottle Cap and Straw

A · Very low PFAS

Lower concern for this specific component; stainless steel is intrinsically PFAS-free.

Verdict: BuyStainless steel cap and straw carry no established leaching or coating hazards; brand transparency on water filtration is adequate for this component.

Stainless steel bottle caps and straws are inherently free of PFAS coatings and do not require water-resistant or non-stick treatments. Clearly Filtered makes no public PFAS claims for this component, but the material itself poses minimal fluorochemical risk.

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Material

Stainless steel cap and straw

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.

Helps the grade

No PFAS disclosure

No public statement about PFAS in this product.

Hurts the grade

The full breakdown

What it's made of and why it matters

This product is a stainless steel cap and straw assembly, likely 18/8 or 18/10 food-grade stainless steel (chromium-nickel alloy). Stainless steel is chemically inert at normal use temperatures and does not leach harmful substances into water or beverages. Unlike coated metal caps or plastic straws, it has no polymer coating that can degrade, no enamel glaze that can chip, and no internal resin finish to off-gas. The material is inherently resistant to corrosion and microcracking from repeated washings.

The brand's record and disclosure

Clearly Filtered markets itself as a water filtration brand focused on contaminant reduction (chlorine, sediment, taste). The company does not publicly disclose third-party testing results or material certifications (e.g., NSF, FDA approval statements) for this specific cap and straw assembly on widely available sources. No recalls, health complaints, or material controversies have been identified in public records for this component. The brand's silence on PFAS in their marketing materials is notable but not unusual for stainless steel hardware.

How it compares in its category

Stainless steel caps and straws are among the safest material choices for filtered water bottles, alongside borosilicate glass lids. Most competitor bottles in this category use plastic caps (polypropylene or tritan) or combination metal-rubber seals, which introduce potential for BPA-free plastic off-gassing or rubber degradation over time. Stainless hardware outlasts plastic in lifespan and requires no replacement due to coating breakdown. This positions the Clearly Filtered cap and straw favorably in durability and chemical inertness.

If you buy it

Hand wash the stainless cap and straw with mild soap and warm water rather than dishwasher cycles if longevity is a priority; repeated high-heat cycles can eventually dull the finish but do not compromise safety. Inspect the threaded seal annually for minor corrosion, which is rare but can occur in very hard or chlorinated water over years of use. Replace only if cross-threading or leakage develops. Store dry between uses to prevent mineral buildup in the straw interior.

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.”

None known

Microplastic or corrosion particle release

Stainless steel does not shed microplastics. Minor surface corrosion (white or rust spots) is cosmetic and not a health risk in food-grade alloys, though extremely rare in 18/8 stainless.

Possible

Nickel leaching from stainless steel

Food-grade stainless steel (18/8) contains chromium and nickel. In acidic beverages or extended storage, trace nickel leaching is theoretically possible but far below FDA limits for food contact surfaces. No incident reports exist for this product.

None known

Rubber or seal degradation (if present)

This product is stainless cap and straw only. If seals or gaskets are silicone or rubber, manufacturer material specifications are not publicly disclosed; assess during inspection.

None known

Coating or enamel flaking

Stainless steel hardware carries no coating in the traditional sense. Bare metal finish eliminates risk of lead or cadmium from ceramic glazes or enamel finishes.

Possible

Bacterial biofilm in straw interior

Metal straws are susceptible to biofilm buildup if not thoroughly dried or cleaned regularly, particularly in warm climates. This is a hygiene issue, not a material toxicity issue, but warrants attention during maintenance.

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.

More filtered water bottles 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.