Flex · Tampons
Flex Disc Daily Liners Menstrual Pads Bundle
Lower PFAS concern; standard period-pad materials rarely treated with fluorochemicals, but no independent verification.
Flex Daily Liners are cotton-based absorbent pads with no known waterproof/grease-resistant coatings typical of PFAS-treated products. The brand makes no PFAS claims and public materials disclose no Teflon-family coating treatments. No third-party lab data or certifications are publicly available, limiting full certainty.
Shop Flex on Amazon →Material
Cellulose, absorbent core, cotton-based layers
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
Category baseline
period care is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
Safe base material
Made from a material with no inherent PFAS use (ceramic, mineral, or natural fiber).
The full breakdown
What it's made of and why it matters
Flex Daily Liners use cellulose and cotton-based absorbent cores, materials with minimal chemical processing compared to synthetic polymers. Cellulose is naturally derived and does not require flame retardant or antimicrobial chemical treatments typical of synthetic pads. The cotton layers reduce reliance on polyacrylate super-absorbents, which can shed microplastics; however, conventional cotton may carry pesticide residues unless certified organic. No adhesive or plastic backing is reported for these liners, lowering leachate risk.
The brand's record and disclosure
Flex has not published detailed material safety data sheets or third-party certifications (e.g., standard 100 by OEKO-TEX, Cradle to Cradle) for these liners. The brand's silence on PFAS and heavy-metal testing is typical of the menstrual-product industry but represents a disclosure gap rather than confirmed harm. No major recalls or safety controversies are on record for Flex menstrual liners. Independent testing by nonprofit groups (EWG, others) has not flagged Flex products as outliers.
How it compares in its category
Flex liners are positioned as a natural-materials alternative to fully synthetic pads but lack the third-party verification of brands like Cora, Seventh Generation, or Organyc. Most period-pad brands, Kotex, Always, Tampax, use polyacrylate cores and plastic backings; Flex's cellulose approach is less chemically complex. Daily liners in general carry lower chemical risk than overnight pads because they are thinner and see shorter wear times, reducing leaching and irritation potential.
If you buy it
Change liners daily or when saturated to prevent bacterial growth and skin irritation; do not flush or compost, as cellulose can still clump. Store in a cool, dry place away from direct sunlight to prevent mold. Discontinue use if rash, itching, or odor develops, which may indicate sensitivity to cotton pesticides or adhesive residues. If seeking maximum transparency, contact Flex directly to request material origin, dye type (azo vs. reactive), and formaldehyde resin absence confirmation.
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.”
Azo dyes and formaldehyde resins
Cotton textiles in menstrual products are sometimes treated with acid azo dyes or formaldehyde-releasing finishes for color or shape retention. No recalls or test reports of Flex liners document this, but brand does not publicly disclose dye chemistry or resin use.
Pesticide residues in conventional cotton
If liners use non-organic cotton, residues from synthetic pesticides (chlorpyrifos, pyrethroids) may be present at trace levels. Flex does not specify organic certification; conventional cotton in intimate-contact products poses minor but documented dermal and systemic exposure risk over chronic use.
Microplastic shedding
Cellulose-based liners are less prone to microplastic release than polyacrylate cores, but paper and wood pulp fibers can fragment under friction. No studies on Flex liners specifically; risk is lower than fully synthetic alternatives.
Adhesive leachates and irritants
Daily liners typically use adhesive to secure to underwear; formulation is not disclosed by Flex. Acrylate-based adhesives can leach plasticizers or unreacted monomers, especially with heat or sweat; skin contact is direct and prolonged.
Bacterial overgrowth and vulvovaginal irritation
Cellulose cores are not inherently antimicrobial; moisture and occlusion promote bacterial growth if liners are not changed regularly. This is a use-practice risk, not a manufacturing defect, but should be emphasized for products marketed as 'daily wear.'
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.
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Cora
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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.