Onia Swim Onia Sky Blue One Piece Swimsuit Scoop Neck Open Back Nylon Xs New
Lower concern than water-repellent coating-treated swimwear, but Onia doesn't disclose PFAS practices.
This basic nylon one-piece has no disclosed water-repellent or stain-resistant treatment. Nylon doesn't inherently require PFAS, but many manufacturers apply water-repellent coating finishes to swimwear.
The better-graded swap
Patagonia
Patagonia Women's Bottom Turn Racerback Bikini Top
90/100 safety
Same rubric that flunked this product. The swap earned Excellent.
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Nylon swimwear (primary synthetic fiber)
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
What Onia Swim Onia Sky Blue One Piece is made of, ingredients and materials
This Onia one-piece is nylon, a synthetic polyamide fiber commonly used in swimwear for stretch, durability, and quick-dry properties. Nylon itself is chemically stable in its finished form and does not leach harmful monomers into skin or water under normal wear conditions. The scoop neck and open-back design mean minimal dye contact with skin during typical use, reducing any risk from residual dyes in the fabric.
What’s concerning
Category baseline
The starting point for this type of product, before anything specific to this product is counted.
No PFAS disclosure
No public statement from the brand about PFAS in this product.
Degradation and microfiber shedding
All synthetic swimwear sheds microfibers into water with wear and washing. Nylon shedding is not unique to Onia; use a wash bag and cold water to minimize environmental release, though complete prevention is not feasible with synthetic fabrics.
What’s reassuring
Base material not linked to PFAS
The main material recorded for this product is not one associated with PFAS.
Azo dyes and color fastness
Onia does not disclose dye sourcing or azo restrictions. No complaints or recalls tied to this brand's dyes are documented. Standard industry practice assumes restricted azo compounds, but independent verification is absent.
Formaldehyde / VOCs
Nylon swimwear typically does not require formaldehyde resins for wrinkle or shrink resistance. No evidence of formaldehyde-treated Onia products appears in public records or complaint databases.
Source, ATSDR ↗Antimony in polyester blends
This product is pure nylon, not polyester, so antimony catalyst residues are not applicable. Antimony risk is relevant only to products containing polyester fiber.
Allergic contact dermatitis from dyes or finishes
No documented skin reactions or allergic complaints specific to Onia swimwear are public. Standard pre-wear rinsing mitigates residual dye exposure. Individuals with known dye sensitivities should patch-test or contact the brand for dye composition details.
The full breakdown
The brand's record and disclosure
Onia is a direct-to-consumer swimwear brand with no public chemical disclosure policy or third-party certifications (e.g., Oeko-Tex, bluesign) on record. The brand has not faced documented chemical safety recalls or regulatory warnings related to their swimwear. No evidence of formaldehyde resin finishes or azo-dye controversies specific to Onia products is available in public databases.
How it compares in its category
Standard nylon swimwear sits in the mid-range for chemical transparency. Unlike luxury brands offering bluesign or Oeko-Tex certification, Onia does not market independent testing; unlike mass-market brands, no chemical safety complaints have surfaced. Nylon is inherently lower-risk than spandex blends if dyes are rinsed properly post-manufacture, which is standard industry practice.
If you buy it
Rinse the garment in cool water before first wear to remove loose dyes and any residual manufacturing chemicals. Wash in cool water with mild detergent after each use; avoid hot water or chlorine, which can degrade nylon elasticity and dyes. Air-dry away from direct heat and sunlight to preserve color and fiber integrity. Replace when elastic loses recovery or seams show signs of degradation, typically after 50-100 wears with proper care.
What we don’t know
- Basis
- Model estimate, 72% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- Onia has made none
Formulations change between production runs, so check the current label. How we grade.
Better-graded alternatives in Swimwear
Patagonia
Women's Bottom Turn Racerback Bikini Top
- Nylon/polyester blend with elastane (standard swimwear)
- The brand calls it PFAS-free, which we have not verified
- Elastane (spandex) degradation under heat or chlorine
More swimwear grades
How we score, every product runs through the same public 0-100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.