20/ 100
F
OverallF0/100
Lowa Men's Zephyr GTX Mid TF

Lowa · Hiking Shoes & Trail Runners

Lowa Men's Zephyr GTX Mid TF

F · High PFAS

Gore-Tex membrane likely contains PFAS; Lowa provides no disclosure.

Verdict: SkipSolid hiking boot with established durability; Gore-Tex carries likely PFAS exposure; Lowa's silence on chemical disclosure is a transparency gap. Mitigation: use as intended, avoid high-heat cleaning.

This hiking boot uses Gore-Tex, a Teflon-family coating-based waterproof lining historically made with PFOA/PFOS or modern PFAS alternatives. Lowa has not publicly disclosed PFAS policies or safer alternatives for this model.

Still want this one anyway? Check the price on Amazon. We’d swap it.

Material

Nubuck leather upper, Gore-Tex GTX membrane (Teflon-family coating-based waterproof liner)

Brand disclosure

Brand is silent on PFAS

Lab data

No public lab test

Why this grade

No PFAS disclosure

No public statement about PFAS in this product.

Hurts the grade

Waterproof / stain-resistant treatment

water-repellent coating treatments have historically used PFAS.

Hurts the grade

Category baseline

clothing is a category where PFAS exposure is more common.

Hurts the grade

The full breakdown

What it's made of and why it matters

The Zephyr GTX Mid TF uses nubuck leather (abraded surface finish, more porous than full-grain) bonded to a Gore-Tex membrane. Gore-Tex is a Teflon-family coating laminate designed to repel water while allowing vapor transmission; this structure inherently requires fluorinated chemistry. The nubuck upper will absorb water and oils more readily than sealed leather, requiring regular treatment. The combination creates a durable but chemically complex assembly.

The brand's record and disclosure

Lowa has not published PFAS-free claims, supply-chain transparency reports, or chemical disclosure statements for this model. The brand is known for quality manufacturing (German-engineered, established 1923) but does not publicly engage with persistent chemical concerns in outdoor gear. No product-specific recalls or contamination incidents are documented in public records. This is a case of product silence rather than demonstrated safety.

How it compares in its category

Most mid-range hiking boots with Gore-Tex carry the same PFAS-linked waterproof membrane; this is not a Lowa-specific problem but a category standard. Alternatives using non-fluorinated membranes (eVent, Sympatex) exist but are rarer in hiking boots and often cost more. Lowa's reputation for leather durability and resoling is above-average, meaning this boot may see longer life than typical alternatives, offsetting some replacement-cycle impact. The TF (tactical fit) variant is standard-duty footwear with no known hazardous modifications.

If you buy it

Avoid machine washing and high-temperature settings; hand clean with cool water and mild soap, then air dry away from direct heat. Reapply nubuck protectant every 6-12 months to maintain water resistance and reduce reliance on Gore-Tex's Teflon-family coating layer. Inspect the membrane seams annually; if seams separate, the boot's waterproofing fails and replacement is practical. Expect 3-7 years of service depending on use intensity; Lowa offers resoling, which extends life but does not eliminate the Gore-Tex membrane hazard.

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.”

Likely

Teflon-family coating (PFAS-bearing) waterproof membrane

Gore-Tex membranes contain fluorinated compounds to function. Lowa provides no alternative or disclosure; no independent test of this specific boot is on record. Risk is primarily skin contact during wear and manufacturing/landfill stages, not acute.

Possible

Formaldehyde in leather tanning and finishing

Nubuck leather finish involves chrome or aldeyhyde-based tanning and surface treatments. Lowa does not certify Leather Working Group (LWG) standards or disclose tanning chemistry. Off-gassing risk is low after production curing, but direct skin contact (if tannin residue present) could cause irritation in sensitized individuals.

Possible

Azo dyes in leather and fabric dyeing

Nubuck and any synthetic reinforcement fabrics may contain azo dyes, which can release carcinogenic amines under sweat and moisture. No ban or certification standard is documented for this product; risk is low for normal foot contact but increases with abrasion and sweat exposure over years.

Possible

Adhesive off-gassing (polyurethane-based)

Bonding Gore-Tex to leather and sole assembly typically uses polyurethane adhesives, which can off-gas volatile organic compounds (VOCs) for weeks to months. Ventilation and air drying after purchase reduces exposure. No specific data on Lowa's adhesive chemistry is public.

Reported

Degradation and microfiber shedding of Gore-Tex

Gore-Tex membranes have been documented to degrade and shed microfibers into soil and water once boots are discarded or heavily abraded. This is a known lifecycle issue, not brand-specific. Lowa does not offer closed-loop recycling or material take-back for end-of-life boots.

What we don’t know

This grade is a model-based estimate from public materials, coatings, and brand disclosure at 45% 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 hiking shoes & trail runners 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.