Core Daily Wrapped Liners vs Leak-Fighting Cotton Brief Underwear: which is safer?

Kotex Core Daily Wrapped Liners is the clear pick. Thinx Leak-Fighting Cotton Brief Underwear carries a failing PFAS grade, and we never recommend buying a failing product.

Our pick

Kotex Core Daily Wrapped Liners

Kotex

Core Daily Wrapped Liners

PFAS grade

Good 70/100

Overall grade

Poor 48/100

Verdict

Buy

Hazard flags

⚑ 4

Material

cotton, rayon, adhesive (nonwoven blend)

Confidence

72%

PossibleSynthetic adhesive leachables

ReportedFragrance allergens (if scented variant)

PossibleMicroplastic shedding from nonwoven backing

Thinx Leak-Fighting Cotton Brief Underwear

Thinx

Leak-Fighting Cotton Brief Underwear

PFAS grade

Poor 25/100

Overall grade

analysis pending

Verdict

pending

Hazard flags

none flagged

Material

Cotton blend with waterproof gusset coating (unspecified)

Confidence

42%

Where these two actually differ

  • We flag Synthetic adhesive leachables, Fragrance allergens (if scented variant), Microplastic shedding from nonwoven backing and PFAS water-resistance coating (undisclosed) on the Kotex and not on the Thinx.
  • The Kotex is cotton, rayon, adhesive (nonwoven blend) where the Thinx is Cotton blend with waterproof gusset coating (unspecified), which is most of the difference in these two grades.
  • The gap is 45 points, wide enough that this is not a close call, and the Kotex is the one to buy.
  • We are less certain about the Thinx grade, at 42% confidence against 72%, because it discloses less.

Both products run through the same public rubric: materials, coatings, brand disclosure, lab findings, and recalls, plus a beyond-PFAS hazard analysis. Grades are model-based estimates, not lab tests. How grades work →

More panty liners: see the full ranking