Patagonia Women's Long Sleeved Swell Seeker One Piece Swimsuit
Swimsuit probably treated with PFAS-based water-repellent coating; Patagonia silent on PFAS.
This swimsuit contains synthetic nylon with water-repellent finish typical of swimming apparel. Patagonia refuses to say whether this product uses PFAS-free water-repellent coating chemistry, and most conventional swimsuit water treatments rely on PFAS though some brands now offer PFAS-free options.
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Nylon/polyamide with water-repellent coating (water-repellent coating) finish
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
Standard nylon swimwear water-repellent coating finishes are predominantly PFAS-based. Patagonia has not disclosed whether this product uses fluorinated or alternative chemistry. Graded separately per instructions, but confirmed likely based on material and finish type.
Source: ATSDR ↗Formaldehyde / VOCs
Formaldehyde-releasing resins may be used in elastane blends or elastic components within seams or binding. Patagonia does not publish formaldehyde residue testing; risk is lower than in untested imported fast-fashion but not excluded.
Source: ATSDR ↗Microplastic shedding from synthetic fiber
All nylon garments shed microfibers when washed. Swimwear experiences higher wash frequency and mechanical stress than outerwear, increasing shedding rate. No product-specific data exists; this is a material-class issue, not brand-specific.
What’s reassuring
Azo dyes (synthetic colorants)
Nylon swimwear can be dyed with azo dyes, some of which are restricted in EU and other markets. No specific recalls or reports for Patagonia Women's Swell Seeker colorants; brand uses third-party mills with varying dye standards.
Antimony in polyester/polyamide
Antimony is a catalyst used in some polyester production but rarely in nylon synthesis. This product is nylon-based, so antimony risk is not a primary concern for this garment.
The full breakdown
What it's made of and why it matters
This swimsuit is constructed from nylon (polyamide) fabric with a water-repellent coating (water-repellent coating) finish applied to the surface. water-repellent coating treatments repel water to keep the suit dry longer and improve performance, but historically many brands use PFAS-based chemistry for this purpose because PFAS compounds are extremely effective at water and oil repulsion. Nylon itself is a synthetic polymer with no established lead, cadmium, or heavy-metal leaching concerns at normal use temperatures. The hazard lies primarily in the finish layer, not the base fabric.
The brand's record and disclosure
Patagonia is recognized for environmental commitments and transparency on supply chain practices, but the company has not publicly committed to or disclosed whether it uses PFAS-free water-repellent coating alternatives in swimwear lines. Patagonia does not list PFAS status on product pages or hang tags for this item. The brand has made broad sustainability claims but remains silent on fluorinated water repellents specifically, which is notable given industry-wide movement toward PFAS alternatives (water-repellent coating without PFAS is technically feasible and offered by some competitors).
How it compares in its category
Most mainstream swimwear brands (Speedo, Nike, Rip Curl) also use PFAS-based water-repellent coating as standard; Patagonia is not an outlier in this regard. A small number of brands (e.g., Girlfriend Collective, some organic/eco-lines) offer PFAS-free or untreated nylon alternatives, though these trade off some water repellency. Patagonia's positioning as a premium sustainable brand creates an expectation of clearer disclosure that is not yet met on this specific product.
If you buy it
Wash in cool water with mild detergent before first use to reduce surface chemical residue. Rinse thoroughly after saltwater or chlorine exposure to prevent salt/chlorine buildup, which can degrade the water-repellent coating finish over time. Avoid high heat (machine dry or direct sunlight for extended periods); air dry in shade. Replace when the water-repellent coating begins to bead water less effectively (typically 1-2 years with regular use), as this signals finish degradation; washing does not restore PFAS-based water-repellent coating.
What we don’t know
- Basis
- Model estimate, 55% 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.