Patagonia Women's Sunny Tide One-Piece Swimsuit
water-repellent coating-coated swimsuit material unknown; Patagonia silent on PFAS.
Patagonia's Sunny Tide swimsuit uses synthetic fabrics with water-resistant treatment typical of swim apparel without disclosing PFAS chemistry or water-repellent coating agents. Industry convention often relies on PFOA or PFOS alternatives, but PFAS risk cannot be ruled out without third-party verification or explicit commitment.
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Material
Nylon/polyester blend with water-repellent coating treatment
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
What’s concerning
Waterproof / stain-resistant treatment
Water-repellent treatments have historically contained PFAS chemicals.
Category baseline
PFAS exposure happens more often with clothing products.
No PFAS disclosure
The company has not publicly discussed PFAS in this product.
PFAS
Water-repellent finishes on swimwear typically contain C8 or C6 PFAS unless explicitly reformulated; Patagonia does not disclose water-repellent coating composition, making it probable but not confirmed that legacy fluorochemicals are present.
Source: ATSDR ↗Synthetic microfiber shedding
Nylon and polyester swimwear release microfibers during wear and washing. Patagonia acknowledges this issue in its sustainability materials but has not published mitigation data specific to this garment.
Formaldehyde / VOCs
Polyester/nylon blends may be treated with formaldehyde-based resins during manufacturing to set colors or improve wrinkle resistance; Patagonia restricts formaldehyde in some product lines but does not specify limits for swimwear.
Source: ATSDR ↗Degradation of coating over time
water-repellent coating coatings on nylon/polyester deteriorate within 1-2 years of use, potentially releasing nanoparticles or exposing underlying fibers; no accelerated testing data is public for this specific model.
What’s reassuring
Heavy metals
No recalls or complaints specific to this product for azo-dye carcinogens or cadmium/lead in pigments. Patagonia's general standards likely exclude these, but no third-party certification (e.g., OEKO-TEX) is on record for this swimsuit.
Source: FDA ↗The full breakdown
What it's made of and why it matters
This swimsuit is a nylon and polyester blend treated with a water-repellent coating (water-repellent coating) finish. water-repellent coating coatings historically relied on PFAS compounds to achieve water-shedding performance, though some manufacturers have shifted to PFAS-free alternatives. The base fabrics themselves (nylon and polyester) are stable synthetic fibers with low leaching risk under normal use, but the coating chemistry is the primary concern. Without Patagonia's disclosure of which water-repellent coating system is used, the fluorochemical content remains unknown.
The brand's record and disclosure
Patagonia has a strong environmental and labor reputation but has been notably silent on PFAS phase-out timelines compared to competitors like Allbirds or Patagonia's own commitment to reduce synthetic microfiber shedding. The company has not published a public PFAS elimination roadmap for apparel, though it does restrict certain flame retardants and heavy metals in its product lines. This silence on water-repellent coating chemistry specifically is a gap in transparency for a brand marketed on sustainability.
How it compares in its category
Most mainstream swimwear (Speedo, Nike, Lands' End) uses similar nylon/polyester blends with water-repellent coating treatment, meaning this product is not uniquely exposed. However, some brands (e.g., Girlfriend Collective, some REI house-brand swimwear) now explicitly market PFAS-free water-repellent coating or no-water-repellent coating options. Patagonia's refusal to disclose places it in the middle of the category by transparency standards, not at the forefront of alternatives.
If you buy it
Rinse the swimsuit in fresh water after each salt-water or chlorine exposure to minimize chemical absorption. Wash in cool water with mild detergent; avoid hot water, which can degrade the water-repellent coating and any bonded fluorochemicals. Do not dry-clean or tumble-dry, as heat can accelerate coating breakdown. The water-repellent coating will degrade over 1-2 years with normal use; at that point, replacement is reasonable, and consider requesting PFAS-free details from Patagonia before repurchase.
What we don’t know
- Basis
- Model estimate, 45% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- Patagonia has made none
Formulations change between production runs, so check the current label. How we grade.
Safer alternatives in Swimwear
Speedo
Women's Eco Solid Adult Super Pro Swimsuit
Polyester/nylon blend (standard swimsuit fabric)
Lower concern, typical swimwear without known water-repellent treatment, though Speedo has not disclosed PFAS avoidance.
⚠Risky category by default
Patagonia
Women's Bottom Turn Racerback Bikini Top
Nylon/polyester blend with elastane (standard swimwear)
Lower concern, basic swimwear without water-repellent coating, though Patagonia's broader PFAS practices warrant review.
⚠Risky category by default
Aerie
String Triangle Bikini Top
nylon/polyester blend (standard swimwear)
Lower PFAS concern, untreated swimwear unlikely to require water-repellent coating chemicals.
⚠Risky category by default
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.