Kotex · Tampons
U by Kotex Sleek Tampons
Lower PFAS concern; no red flags in design, but brand offers no transparency.
U by Kotex Sleek Tampons use conventional absorbent materials (rayon, cotton, polypropylene) with no obvious PFAS-risk design features like waterproofing or stain resistance. Kotex has not publicly claimed PFAS-free status or pursued third-party verification.
Shop Kotex on Amazon →Material
Rayon/viscose core, cotton exterior, polypropylene 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
U by Kotex Sleek tampons use a rayon-viscose core (highly absorbent, plant-derived) wrapped in cotton, with a polypropylene plastic applicator and backing layers. Rayon is produced via chemical processing that dissolves wood pulp; residual sodium hydroxide or sulfuric acid can theoretically remain if purification is incomplete, though regulated manufacturers remove these to safe levels. Cotton provides a natural barrier but is not certified organic in this product, meaning pesticide residues are possible though typically minimal in finished goods. Polypropylene is a stable plastic with low leaching risk under normal body temperature and pH conditions.
The brand's record and disclosure
Kotex (Kimberly-Clark subsidiary) does not publish ingredient transparency reports or third-party safety certifications for tampons, and has not publicly addressed PFAS presence or absence. The brand has faced no major product recalls related to tampons in recent years. Unlike some competitors (Seventh Generation, Cora, Rael), Kotex does not highlight organic certification or fluorochemical-free claims, suggesting either standard industry practice or strategic silence. No lawsuit or regulatory action specific to this product line is on public record.
How it compares in its category
Standard tampon design places U by Kotex Sleek in the mainstream tier: functional, widely available, and price-competitive, but less transparent than premium organic or PFAS-tested brands. It lacks third-party environmental or safety certifications that brands like Seventh Generation or Cora advertise. The rayon-cotton blend is typical across conventional tampons and poses lower risk than all-synthetic alternatives. For most users, safety profile is equivalent to other non-organic conventional tampons on US shelves.
If you buy it
Change every 4-8 hours to reduce toxic shock syndrome (TSS) risk, regardless of absorbency grade; this applies to all tampons. Do not leave in overnight or for extended periods. If you experience unusual odor, discharge, or irritation, discontinue and consult a provider, as symptoms may indicate suboptimal manufacturing or individual sensitivity. Store in a cool, dry place; exposure to heat or moisture can degrade applicator or core integrity over months.
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.”
Viscose processing residuals (sodium hydroxide, sulfuric acid)
Regulatory manufacturing standards in the US require thorough purification of rayon before consumer use. No documented cases of residual alkali or acid harm from Kotex tampons; industry-wide concern is low but not independently verified for this brand.
Pesticide residues in non-organic cotton
U by Kotex Sleek does not specify organic cotton, so conventional cotton may contain trace pesticide residues (typically well below hazard thresholds). Vaginal mucosa absorption of such residues is theoretically possible but epidemiologically unproven as a clinical risk.
Polypropylene applicator degradation or particle shedding
Polypropylene is chemically stable at body temperature and vaginal pH. Microplastic shedding is not documented for standard applicators; risk is theoretical rather than established.
Bleaching agents or dioxins in rayon processing
Elemental chlorine-free (ECF) or totally chlorine-free (TCF) bleaching is now standard in US and EU rayon manufacture. Kotex does not specify method, but regulatory limits on dioxin residues in finished tampons are enforced; no recalls or contamination reports exist for this brand.
Toxic shock syndrome (TSS) risk
TSS is associated with high-absorbency tampons and prolonged use, not brand-specific. All tampons carry this risk if left in too long. Kotex Sleek is not a super-plus variant, so TSS risk is standard and manageable with proper use (4-8 hour changes).
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.
Safer alternatives in Tampons
Seventh Generation
Organic Cotton Tampons Applicator
organic cotton (tampon & applicator core); cardboard applicator
Lower-concern buy, organic cotton & MADE SAFE cert reduce PFAS risk, though brand is silent on the topic.
✓Verified PFAS-free by a third party
Lola
Organic Cotton Tampons
organic cotton (no synthetic coatings)
Lower concern, uncoated organic cotton with transparent PFAS-free positioning and third-party certification.
✓Verified PFAS-free by a third party
Cora
Organic Tampons with Applicator
organic cotton tampon with cardboard/plastic applicator
Lower-concern choice; organic base material and MADE SAFE cert suggest thoughtful sourcing, but no explicit PFAS commitment.
✓Verified PFAS-free by a third party
More tampons 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.