Brooks · Synthetic Athletic Insoles & Orthotics
Brooks Women's Glycerin 23
Running shoe with likely water-resistant 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.
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Knit textile upper with water-repellent coating treatment
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
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What Brooks Women's Glycerin 23 is made of, ingredients and materials
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.
What’s concerning
Category baseline
The starting point for this type of product, before anything specific to this product is counted.
No PFAS disclosure
No public statement from the brand about PFAS in this product.
Waterproof / stain-resistant treatment
Water-repellent coating treatments have historically used PFAS.
PFAS
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.
Source, ATSDR ↗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’s reassuring
Formaldehyde / VOCs
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.
Source, ATSDR ↗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.
How is this PFAS grade calculated?
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 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.
What is not known about PFAS in this product?
- Basis
- Model estimate, 45% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- Brooks has made none
Formulations change between production runs, so check the current label. How we grade.
What are the PFAS-free alternatives to Brooks Women's Glycerin 23?
Cotton Insole
- Cotton with possible latex or synthetic backing
- We found no PFAS statement from the brand
- Adhesive/backing composition (unknown)
2 hazards checked on this product, all on its full breakdown.
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Addias Men's Ortholite Comfort Insoles
- Ortholite cushioning foam, polyurethane base
- Volatile organic compounds (VOCs) from polyurethane
3 hazards checked on this product, all on its full breakdown.
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- EVA foam, mesh textile lining
- Azo dyes in mesh textile
3 hazards checked on this product, all on its full breakdown.
Find an alternative on AmazonMore synthetic 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.