U by Kotex Security Lightdays Liners
Skip until brand confirms PFAS absence in adhesives and absorbents.
U by Kotex provides no public PFAS disclosure for this liner. Period-care adhesives and absorbent materials sometimes contain PFAS; independent testing data is unavailable.
The better-graded swap
Aunt Flow
Aunt Flow Pads
100/100 safety
Same rubric that flunked this product. The swap earned Excellent.
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
nonwoven absorbent core, adhesive backing
Lab data
No public lab test
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What U by Kotex Security Lightdays Liners is made of, ingredients and materials
U by Kotex Lightdays Liners use a nonwoven absorbent core (typically polypropylene or cellulose-based) with an adhesive backing for securing to underwear. Nonwoven materials are engineered fibers bonded together and do not shed microplastics under normal use. The adhesive formulation is the critical variable, water-based and hot-melt adhesives have different leachate profiles, and some adhesive systems have historically contained fluorochemicals (PFAS) to enhance water resistance in the backing layer.
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.
PFAS
PFAS is graded separately (60/100 safety). Adhesive backing formulations in menstrual products are a known vector for PFAS; Kotex has not disclosed whether water-resistant adhesives in this liner contain fluorochemicals. Possible exposure during wear and disposal.
Source, ATSDR ↗Fragrance allergens
U by Kotex Lightdays Liners are scented products (fragrance added to the nonwoven or adhesive layer). Fragrance compounds can trigger contact dermatitis or allergic sensitization, particularly in users with sensitive vulvar skin or known fragrance sensitivities. No ingredient disclosure of specific fragrance chemicals is publicly available.
Adhesive skin contact irritation
Direct prolonged contact between the adhesive backing and skin can cause localized irritation, erythema, or dermatitis in susceptible individuals. Risk increases if adhesive remnants remain on skin after removal or if the backing loosens during wear, creating uneven pressure points.
What’s reassuring
Microplastic shedding from nonwoven core
Nonwoven polypropylene or cellulose fibers bonded in this liner do not degrade or fragment during normal wear or handling. No evidence of microplastic release into the body or environment under standard use conditions for this product type.
Heavy metals
No recalls or reports of lead, cadmium, or other heavy metals in U by Kotex liners or their parent materials. Standard pulp and nonwoven production do not introduce heavy metals, and no evidence suggests contamination in this SKU.
Source, FDA ↗How is this PFAS grade calculated?
The brand's record and disclosure
Kotex (Kimberly-Clark) has not publicly disclosed the chemical composition of adhesives or absorbent treatments in U by Kotex liners, nor has the brand published certifications for PFAS absence. The brand maintains silent positioning on fluorochemical use despite industry-wide scrutiny of menstrual products for PFAS contamination. No recalls or safety warnings for this specific SKU are on record; however, absence of disclosure is not absence of hazard.
How it compares in its category
Menstrual liners span a spectrum of material choices, conventional nonwoven (U by Kotex, Kotex, Tampax), organic cotton liners (Seventh Generation, Cora), and reusable fabric options. Nonwoven-core products typically cost less and offer consistent absorbency but lack transparency around adhesive chemistry. Brands explicitly certifying PFAS-free formulations (Cora, Rael) or using certified organic materials provide higher disclosure, whereas Kotex's silent stance places this product in the mid-transparency tier.
If you buy it
Store in a cool, dry place away from direct sunlight to avoid adhesive degradation. Use within the printed expiration date, as adhesive performance and material integrity decline over time. Discontinue use immediately if you experience skin irritation, rash, or localized reactions; this may indicate sensitivity to the adhesive, fragrance, or residual processing chemicals. If PFAS disclosure becomes important to you, contact Kimberly-Clark directly to request confirmation of adhesive composition.
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
- U by Kotex has made a specific claim
Formulations change between production runs, so check the current label. How we grade.
What are the PFAS-free alternatives to U by Kotex Security Lightdays Liners?
- A third party reports verifying it as PFAS-free
- Fragrance allergens (if scented variant)
2 hazards checked on this product, all on its full breakdown.
- organic cotton with natural fibers
- The brand calls it PFAS-free, which we have not verified
- Microplastics
Organyc
100% Certified Organic Cotton Tampons Cardboard Applicator
- 100% organic cotton with cardboard applicator
- We found no PFAS statement from the brand
- Cardboard applicator structural integrity over time
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70Cora Organic TamponsCompare vs Natracare →All period care →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.