Kotex Maxi Overnight Pads
Waterproof pad backing raises PFAS risk; brand silent on ingredients.
Kotex does not disclose PFAS or waterproof coating details. Period pads with waterproof layers commonly use PFAS-based treatments, though unconfirmed here. Low transparency limits confidence.
The safe swap
Nana
Nannopad Pad Feminine Multipack
70/100 safety
Same rubric that flunked this product. The swap earned Good.
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Cellulose, absorbent core, waterproof backing layer
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
What’s concerning
Waterproof / stain-resistant treatment
water-repellent coating treatments have historically used PFAS.
Category baseline
period care is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
PFAS
Waterproof polymer backing in conventional pads typically contains fluorinated chemicals (PFAS) to repel moisture. Kotex does not disclose backing composition, and waterproof backing is a known source of PFAS exposure via skin contact and potential environmental release. This is the primary chemical hazard for this product.
Source: ATSDR ↗Undisclosed adhesives and coatings
Adhesive layers bonding the absorbent core to the backing and any topsheet coatings are not detailed by the brand. Common adhesives in pads can include acrylics or hot-melt polymers; while low-risk, lack of disclosure prevents verification of specific formulations or residual solvents.
Skin irritation or contact sensitization
Some users report localized irritation from synthetic backing or synthetic fibers in conventional pads. This is typically mild and product-specific rather than a class-wide hazard. Kotex does not market hypoallergenic or dermatologist-tested claims for the Overnight line, leaving individual risk undefined.
What’s reassuring
Formaldehyde / VOCs
No documented cases of formaldehyde contamination in Kotex pads have been reported. Cellulose topsheets do not inherently require formaldehyde resins, though some brands use them for softness or wrinkle resistance; Kotex has not disclosed use of these agents.
Source: ATSDR ↗Chlorine bleaching residues (dioxins)
Historically, period products were bleached with elemental chlorine, creating trace dioxins. Industry transitioned to elemental chlorine-free (ECF) and totally chlorine-free (TCF) processes in the 1990s-2000s. No current evidence suggests Kotex pads retain problematic dioxin levels, but the brand does not certify TCF status.
The full breakdown
What it's made of and why it matters
Kotex Maxi Overnight pads use a cellulose-based absorbent core, which is biologically inert and does not leach chemical compounds during normal use. The waterproof backing layer (typically polyethylene or polypropylene composite) is where chemical concerns concentrate. Cellulose itself has no established toxicity risk, but the backing's composition and any applied treatments are not fully disclosed by the brand, creating uncertainty around PFAS and other water-repellent coatings commonly used in period products.
The brand's record and disclosure
Kotex (owned by Kimberly-Clark) has not published detailed ingredient transparency reports or safety certifications specific to this product line. The brand does not market chemical-free or PFAS-free credentials, nor does it provide material safety data sheets (MSDS) to consumers. Kimberly-Clark has faced historical scrutiny over dioxin residues in tampons (largely addressed by industry-wide process changes decades ago) but has not issued modern, comprehensive ingredient disclosures for pad backing materials. Absence of transparency is not proof of hazard, but it limits independent verification.
How it compares in its category
Most conventional period pads (Always, Tampax, store brands) use similar waterproof backing polymers and share the same disclosure gap. Kotex Maxi Overnight is mid-range in absorbency design and does not stand out as higher-risk than competitors. Organic or PFAS-free alternatives (Cora, Rael, Aunt Flow, Natracare) explicitly market chemical transparency and PFAS avoidance, making them visibly safer choices if PFAS concern is primary. Kotex's mainstream positioning means it is widely tested by consumer groups, but no major recalls or contamination events have been documented in recent years.
If you buy it
Store pads in a cool, dry place; heat and humidity do not trigger degradation of cellulose or plastic backing under normal conditions, so no special storage is needed. Replace pads every 4-8 hours during use to minimize skin contact duration and reduce any residual chemical migration risk. Do not flush pads; dispose in sealed waste to prevent environmental water contamination. If you experience skin irritation, redness, or unusual odor, discontinue and consult a dermatologist; individual sensitivities to synthetic backing or undisclosed additives are rare but possible.
What we don’t know
- Basis
- Model estimate, 35% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- Kotex has made none
Formulations change between production runs, so check the current label. How we grade.
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More period pads 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.