Most swimwear is made from synthetic fabrics — nylon, polyester, spandex — that don’t inherently require PFAS. The concern comes from additional performance treatments applied to some swimwear and beachwear, and from cover-ups that carry water-resistance or stain-resistance claims. Here’s how to navigate it.
Why Swimwear and Beachwear Can Contain PFAS
PFAS in the context of swimwear and beachwear aren’t present in the fiber itself — nylon and polyester don’t contain PFAS as part of their polymer structure. PFAS enter the picture through performance treatments applied to the fabric surface after it’s formed.
The most common PFAS-related scenarios in swimwear:
Quick-dry and water-repellent rash guards: A rash guard marketed as water-repellent (not just quick-drying from its fiber properties) may have a DWR-type coating — historically fluorochemical, sometimes PFAS-free in reformulated versions.
Stain-resistant children’s swimwear: Stain resistance claims on swimwear, particularly in kids’ categories, are the highest PFAS signal. Fluorochemical treatments are effective at repelling sunscreen, sand, and food stains — and have been used in this application.
Water-resistant beach cover-ups: A cotton or linen cover-up that’s marketed as water-resistant or quick-dry has likely been treated with a performance finish. That finish may or may not be PFAS-based.
UV-protective cover-ups with additional performance claims: UPF ratings come from construction; when they’re combined with water resistance or stain resistance claims, chemical treatments are more likely.
Pool environment consideration: Chlorine is an oxidizing agent that can accelerate the degradation of fabric surface treatments and may increase the rate of chemical migration from treated surfaces. This makes the quality and safety of finishes more consequential in pool settings than in dry-air wear.
Finishes and Claims to Watch For
High concern:
- “Stain-resistant” on swimwear or rash guards
- “Water-repellent” on a beach cover-up or rash guard (vs. the inherent hydrophobia of plain synthetic)
- “Quick-dry finish” on a natural fiber swim cover
- Multiple performance claims combined (water-resistant + quick-dry + stain-resistant)
Low concern:
- Plain nylon or polyester swimwear without performance finish claims
- “Quick-dry” on a plain synthetic (this is the fiber’s inherent property, not a coating)
- “UPF 50+” on a tightly woven fabric without additional claims
- OEKO-TEX® certified swimwear of any fiber type
What PFAS-Free Swimwear Looks Like
Certified recycled nylon without performance treatments: ECONYL® and similar recycled nylons with OEKO-TEX® or bluesign® certification and no additional performance finish claims is the strongest category.
OEKO-TEX® certified plain swimwear: The certification tests the finished product for restricted substances. A plain bikini or swim trunk with OEKO-TEX® STANDARD 100 has been tested and meets the restricted substances standard.
Natural fiber cover-ups without treatment claims: A linen, cotton, or Tencel® cover-up that doesn’t claim water resistance or stain resistance is almost certainly free of PFAS-based finishes. Just avoid the “wrinkle-free” or “water-resistant” claims.
Brands with transparent material policies: Several swimwear brands have made explicit PFAS-free commitments. Brands with a public materials or sustainability page that addresses PFAS are worth prioritizing.
How to Read Labels and Product Descriptions
For swimwear, the label tells you fiber content but not finish chemistry. On the product page:
- Read the marketing bullets — look for any performance claims beyond basic fit and color
- Check the “materials” or “specifications” section for finish disclosures
- Look for certification logos (OEKO-TEX®, bluesign®, GRS)
- Search the brand’s website for “PFAS,” “PFC,” or “fluorochemical” — brands that have eliminated them usually say so
If the product page doesn’t mention finishes and the brand’s materials page doesn’t address PFAS, a direct question to customer service — “Is this swimwear treated with any stain-resistant or water-repellent chemical finish?” — usually yields a direct answer.
Safer Fabrics and Brands to Consider
For swimwear bodies:
- OEKO-TEX® certified recycled nylon (ECONYL® blends from various brands)
- bluesign® certified nylon or polyester
- Plain certified synthetic without additional treatment claims
For cover-ups and beach layers:
- GOTS organic cotton (linen, muslin, voile styles for cover-ups)
- OEKO-TEX® certified Tencel® or bamboo viscose
- Hemp-cotton blends from certified brands
- Linen (minimal treatment needed — natural drape and weight work in warm climates)
What to look for in brand selection:
- An explicit PFAS or PFC-free policy on their website
- OEKO-TEX® or bluesign® certification on specific products or across the line
- Recycled content with verified certification (GRS) to confirm the recycled sourcing claim
FAQ
Do I need to worry about PFAS in regular swimwear?
Plain nylon or polyester swimwear without performance treatment claims is lower concern. The primary risk factors are stain-resistant treatments in kids’ swimwear, water-repellent coatings in rash guards, and multi-function performance claims in cover-ups.
Is chlorine in pools a concern for PFAS exposure?
Chlorine can accelerate the degradation of chemical surface treatments, potentially increasing migration off treated fabric surfaces. This is a reason to prioritize PFAS-free certification for swimwear worn in chlorinated pools, particularly for children.
What about recycled nylon — is it PFAS-free?
Recycled nylon fiber itself doesn’t contain PFAS. PFAS can enter the picture through performance treatments applied afterward. OEKO-TEX® certification on the finished swimwear confirms it meets restricted substance standards including for PFAS.
Are organic cotton swimsuits practical?
For casual beach and pool use (not competitive swimming), yes. Cotton absorbs water and is heavier when wet, but it dries quickly in sun and heat. Organic cotton swimwear exists and works well for casual use.
Related reading: PFAS in Clothing: What It Is and How to Avoid It · How to Spot PFAS in Product Descriptions
Scan swimwear and cover-ups with Wove. Download Wove to get an instant fiber and chemical concern grade on any piece of beachwear.
Sources
- Environmental Working Group: PFAS in Consumer Products
- OEKO-TEX®: STANDARD 100 Certification
- Bluesign Technologies: Approved Substances List
- Global Recycled Standard: Certification Requirements