Women's Fastback One Piece Swimsuit vs Women's Bottom Turn Racerback Bikini Top: which is safer?
Patagonia Women's Bottom Turn Racerback Bikini Top is the clear pick. Nike Women's Fastback One Piece Swimsuit carries a failing PFAS grade, and we never recommend buying a failing product.
Nike
Women's Fastback One Piece Swimsuit
PFAS grade
Bad 20/100
Overall grade
Bad 12/100
Verdict
Skip
Hazard flags
⚑ 2
Material
Nylon/polyester blend with water-repellent coating finish
Confidence
45%
PossiblePFAS in water-repellent coating
PossibleMicroplastics shedding
Our pick
Patagonia
Women's Bottom Turn Racerback Bikini Top
PFAS grade
Excellent 90/100
Overall grade
Excellent 86/100
Verdict
Buy
Hazard flags
⚑ 1
Material
Nylon/polyester blend with elastane (standard swimwear)
Confidence
72%
PossibleElastane (spandex) degradation under heat or chlorine
Where these two actually differ
- We flag PFAS in DWR coating and Microplastics shedding on the Nike and not on the Patagonia.
- We flag Elastane (spandex) degradation under heat or chlorine on the Patagonia and not on the Nike.
- The Nike is Nylon/polyester blend with DWR finish 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 Nike grade, at 45% confidence against 72%, because it discloses less.
Both products run through the same public rubric, which covers 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 →
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