Women's Bottom Turn Racerback Bikini Top vs Women's Rio One-Piece Swimsuit: which is safer?
Patagonia Women's Bottom Turn Racerback Bikini Top is the clear pick. Reformation Women's Rio One-Piece Swimsuit carries a failing PFAS grade, and we never recommend buying a failing product.
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
Reformation
Women's Rio One-Piece Swimsuit
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleAzo dyes or restricted colorants
LikelyMicroplastic shedding from synthetic fibers
ReportedSpandex degradation and elasticity loss under heat or UV
Where these two actually differ
- We flag Elastane (spandex) degradation under heat or chlorine on the Patagonia and not on the Reformation.
- We flag Azo dyes or restricted colorants, Microplastic shedding from synthetic fibers and Spandex degradation and elasticity loss under heat or UV on the Reformation and not on the Patagonia.
- The Patagonia is Nylon/polyester blend with elastane (standard swimwear) where the Reformation is Nylon/spandex blend with likely DWR finish, 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 Reformation 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