Brooks · Athletic Insoles & Orthotics
Brooks Women's Glycerin 23
Running shoe with likely water-repellent coating; PFAS status undisclosed by brand
Brooks does not disclose PFAS in Glycerin 23. Water-resistant running shoes commonly use water-repellent coating treatments that may contain PFAS, but Brooks provides no transparency on chemistry.
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Material
Knit textile upper with water-repellent coating treatment
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
clothing 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 Glycerin 23 upper is a knit textile (polyester and nylon blend typical for Brooks running shoes) treated with a water-repellent coating (water-repellent coating) finish. water-repellent coating coatings historically used PFAS-based chemistry to repel water; Brooks does not publicly disclose the chemical class of its water-repellent coating treatment on this model. The mesh and knit materials themselves are not inherently hazardous, but the treatment layer is the chemical concern.
The brand's record and disclosure
Brooks has not published a formal PFAS elimination timeline or commitment as of public record. The brand does not disclose water-repellent coating chemistry on product specification sheets for the Glycerin line. No major textile safety recalls or formaldehyde/azo dye violations are documented for Brooks running shoes. This silence on chemical treatment is the primary disclosure gap relative to competitors like Salomon and some Altra models, which have begun naming safer fluorine-free water-repellent coating alternatives.
How it compares in its category
Brooks Glycerin sits in the premium cushioned running shoe segment where water-repellent coating treatment is standard. Most shoes in this price tier ($150-180) use traditional fluorinated water-repellent coating; some brands (Altra, Cotopaxi-affiliated footwear) now offer fluorine-free water-repellent coating options. Brooks' Glycerin does not market itself as a low-chemical alternative, making it typical for mainstream athletic footwear rather than an outlier in safety profile.
If you buy it
Wash by hand or gentle machine cycle in cold water to reduce heat stress on the water-repellent coating and any polymer components. Avoid high heat drying (air dry preferred); heat can degrade knit integrity and potentially increase leaching from treatments. Replace when midsole cushioning visibly compresses or upper seams separate (typically 300-500 miles for running shoes). If water repellency fades, do not reapply consumer-grade fluorinated water-repellent coating sprays without checking for PFAS-free certifications on the product.
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.”
PFAS in water-repellent coating
Knit upper has water-repellent treatment; Brooks does not disclose chemical composition. Most shoes in this category still use PFAS-based water-repellent coating unless explicitly stated otherwise. Graded separately per your request.
Formaldehyde in textile resins
No recalls or public testing data indicate formaldehyde use in Brooks Glycerin 23 uppers or finishes. Knit athletic textiles rarely require formaldehyde for wrinkle resistance, making this a low-concern hazard class for running shoes.
Azo dyes and allergenic colorants
Brooks does not use restricted azo dyes per standard textile supplier practice in the US market. No documented contact dermatitis or dye-related complaints specific to this model exist in public records.
Antimony in polyester fibers
Polyester content in the knit upper may contain trace antimony as a polymerization catalyst. Levels in finished textiles are typically below migration thresholds for direct skin contact, but prolonged wear in high-sweat conditions could theoretically increase surface accumulation.
Adhesive and sole-upper interface degradation
Brooks running shoes, including the Glycerin line, have occasional reports of upper-midsole separation after 200-400 miles of use. While not a chemical hazard, delamination can expose adhesive residues. This is a durability issue rather than a baseline safety problem.
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.
Safer alternatives in Athletic Insoles & Orthotics
Vionic
Active Full Insole
Foam cushioning, textile upper
Lower concern; typical insole without known PFAS drivers.
⚠Risky category by default
Vionic
Women's Slim Fit Insole
foam, gel, or textile insole construction
Insole material is inherently lower PFAS risk; no brand disclosure found.
⚠Risky category by default
Vionic
Unisex Active Orthotic Full Length Insole
EVA foam, fabric backing, polyurethane adhesive
Lower concern insole; common foam materials, no waterproofing treatment indicated.
⚠Risky category by default
More athletic insoles & orthotics 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.