F

Is Onia PFAS-free?

Across 16 graded products, Onia averages F (51/100). On disclosure, the brand says nothing publicly about PFAS. None of its products grade C or better yet. Grades are model-based estimates, not lab results.

Graded and flagged D and F, we’d swap these

Onia Women's Michelle One-Piece

Onia

Women's Michelle One-Piece

nylon/polyamide blend swimwear

D
D · Elevated

Lower concern for a basic nylon swimsuit, but Onia's silence on water-repellent coating/treatment chemistry leaves moderate uncertainty.

Risky category by default

Onia Michelle One Piece

Onia

Michelle One Piece

nylon/spandex blend (common swimwear)

D
D · Elevated

Lower PFAS concern for a basic nylon swimsuit, but Onia discloses nothing, watch for water-repellent finishes.

Risky category by default

Onia Women's Marilyn One-Piece

Onia

Women's Marilyn One-Piece

Nylon/polyamide swimsuit fabric

D
D · Elevated

Lower concern as a basic nylon swimsuit, but Onia discloses nothing about water-repellent coating treatments used.

Risky category by default

Onia Michelle One Piece in Pale Blue/white at Nordstrom, Size X-Small

Onia

Michelle One Piece in Pale Blue/white at Nordstrom, Size X-Small

Nylon/polyamide blend one-piece swimsuit

D
D · Elevated

Lower concern, standard swimsuit fabric with no known water-repellent coating or stain treatments; brand silent on PFAS.

Risky category by default

Jolie Bikini Top

Onia

Jolie Bikini Top

Nylon and polyamide blend (swim fabric)

D
D · Elevated

Lower concern, standard swim fabric with no known PFAS use, but brand offers no transparency.

Risky category by default

Onia New Black One Piece Swimsuit - New Women | Color: Black | Size: XS

Onia

New Black One Piece Swimsuit - New Women | Color: Black | Size: XS

Nylon with likely water-repellent coating finish (unspecified)

D
D · Elevated

Lower PFAS concern for a basic nylon swimsuit, but Onia's water-repellent coating treatment details are opaque.

Risky category by default

$175 Onia Black Michelle One Piece Swimsuit Small Ymy1223

Onia

$175 Onia Black Michelle One Piece Swimsuit Small Ymy1223

nylon/polyamide blend (standard swimwear fabric)

D
D · Elevated

Lower PFAS concern for basic one-piece swimsuit; no water-repellent coating or water-resistant treatment specified.

Risky category by default

Onia DVF X Ginny One Piece Swimsuit - New Women | Color: Blue | Size: M

Onia

DVF X Ginny One Piece Swimsuit - New Women | Color: Blue | Size: M

Nylon/polyester blend swimwear (likely nylon 6/6 or polyester with elastane)

D
D · Elevated

Lower concern, standard swimwear with no documented PFAS treatment, though no public commitment either.

Risky category by default

Onia Swim | Onia Sky Blue One Piece Swimsuit Scoop Neck Open Back Nylon Xs New | Color: Blue | Size: Xs | Dianaazalea's Closet

Onia

Swim | Onia Sky Blue One Piece Swimsuit Scoop Neck Open Back Nylon Xs New | Color: Blue | Size: Xs | Dianaazalea's Closet

Nylon swimwear (primary synthetic fiber)

D
D · Elevated

Lower concern than water-repellent coating-treated swimwear, but no PFAS transparency from brand.

Risky category by default

Onia Size M Blue Shadow Ginny Block Mesh One-piece Swimsuit $245

Onia

Size M Blue Shadow Ginny Block Mesh One-piece Swimsuit $245

nylon mesh (primary fiber)

D
D · Elevated

Lower concern; basic nylon swimwear with no known PFAS triggers, but brand discloses nothing.

Risky category by default

Onia NWT! Banana Republic Palm Print Isabella Swimsuit - Size Medium - New Women | Color: Gray/Green | Size: M

Onia

NWT! Banana Republic Palm Print Isabella Swimsuit - Size Medium - New Women | Color: Gray/Green | Size: M

Nylon/polyamide swimwear (likely with elastane)

D
D · Elevated

Lower concern; standard swimwear without water-repellent coating claims carries minimal PFAS risk, but brand transparency is absent.

Risky category by default

Onia Women's Soleil One-Piece Swimsuit

Onia

Women's Soleil One-Piece Swimsuit

Nylon/polyamide blend with water-repellent finish

F
F · High PFAS

Skip or contact Onia directly about water-repellent coating chemistry; silent on PFAS is a red flag for performance swimwear.

Waterproof or stain-proof treatment

Onia Women's Arya One-Piece Swimsuit

Onia

Women's Arya One-Piece Swimsuit

nylon/spandex blend with water-resistant treatment

F
F · High PFAS

Moderate PFAS risk due to likely durable water repellency treatment; insufficient brand transparency.

Waterproof or stain-proof treatment

Onia Women's Allegra Tricot One-Piece Swimsuit

Onia

Women's Allegra Tricot One-Piece Swimsuit

Nylon tricot with water-repellent treatment

F
F · High PFAS

Higher PFAS risk due to likely water-repellent coating treatment; Onia provides no transparency.

Waterproof or stain-proof treatment

Onia Rachel Watercolor Stripe Scoop Back Swimsuit

Onia

Rachel Watercolor Stripe Scoop Back Swimsuit

Nylon/polyamide blend (swimsuit fabric), likely with water-repellent coating finish

F
F · High PFAS

Skip if PFAS-concerned; swimwear water-repellent coating treatments commonly contain PFAS, and Onia does not disclose.

Waterproof or stain-proof treatment

Onia Two-Tone Swimsuit

Onia

Two-Tone Swimsuit

Nylon/polyester blend with water-resistant treatment

F
F · High PFAS

Silent on PFAS; typical swimwear water-repellent coating treatment raises concern, request material disclosure.

Waterproof or stain-proof treatment

Every grade uses the same public rubric. How grades work →