Swim Onia Sky Blue One Piece Swimsuit Scoop Neck Open Back Nylon Xs New vs Women's Bottom Turn Racerback Bikini Top: which is safer?
Patagonia Women's Bottom Turn Racerback Bikini Top is the clear pick. Onia Swim Onia Sky Blue One Piece Swimsuit Scoop Neck Open Back Nylon Xs New carries a failing PFAS grade, and we never recommend buying a failing product.
Onia
Swim Onia Sky Blue One Piece Swimsuit Scoop Neck Open Back Nylon Xs New
PFAS grade
Good 65/100
Overall grade
Good 59/100
Verdict
Skip
Hazard flags
⚑ 1
Material
Nylon swimwear (primary synthetic fiber)
Confidence
72%
PossibleDegradation and microfiber 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 Degradation and microfiber shedding on the Onia and not on the Patagonia.
- We flag Elastane (spandex) degradation under heat or chlorine on the Patagonia and not on the Onia.
- The Onia is Nylon swimwear (primary synthetic fiber) where the Patagonia is Nylon/polyester blend with elastane (standard swimwear), which is most of the difference in these two grades.
- The gap is 25 points, wide enough that this is not a close call, and the Patagonia is the one to buy.
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 →
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