Women's Bonded-Scuba V-Neck Swimsuit vs Women's Bottom Turn Racerback Bikini Top: which is safer?
Patagonia Women's Bottom Turn Racerback Bikini Top is the clear pick. COS Women's Bonded-Scuba V-Neck Swimsuit carries a failing PFAS grade, and we never recommend buying a failing product.
COS
Women's Bonded-Scuba V-Neck Swimsuit
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
LikelyFluorinated water-repellent coating finish (PFAS)
PossibleAdhesive leachables from bonded layers
PossibleAzo dyes in polyester
Our pick
Patagonia
Women's Bottom Turn Racerback Bikini Top
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleElastane (spandex) degradation under heat or chlorine
Where these two actually differ
- We flag Fluorinated DWR finish (PFAS), Adhesive leachables from bonded layers, Azo dyes in polyester and Microplastic shedding from wear and wash on the COS and not on the Patagonia.
- We flag Elastane (spandex) degradation under heat or chlorine on the Patagonia and not on the COS.
- The COS is Polyester scuba-knit bonded fabric with likely DWR finishing where the Patagonia is Nylon/polyester blend with elastane (standard swimwear), which is most of the difference in these two grades.
- The gap is 70 points, wide enough that this is not a close call, and the Patagonia is the one to buy.
- We are less certain about the COS grade, at 45% 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 swimwear: see the full ranking