PFAS bans just hit swimwear: what your factory needs to reformulate now

The regulatory landscape just changed for swimwear

As of January 2026, swimwear brands selling into the United States face a patchwork of state laws that specifically target PFAS in textiles. Beginning January 1, 2026, new PFAS prohibitions and reporting requirements take effect in Colorado, Connecticut, Maine, Minnesota, Vermont, and Washington. The requirements target a wide range of consumer products and industries, with meaningful implications for companies across the product supply chain.

This is not theoretical. New York and California have recently imposed sweeping prohibitions on the sale of apparel containing per- and polyfluoroalkyl substances (PFAS). These prohibitions have a broad scope and are effective and enforceable as of January 1, 2025.

Swimwear is explicitly covered. California's definition of "apparel" includes "everyday swimwear." If your swimwear uses fluorinated finishes for water resistance or quick-dry performance, you may already be selling a product that violates state law.

What PFAS actually do in swimwear

PFAS compounds create the low-surface-tension barrier that makes fabrics repel water. In the world of textiles, PFAS are the traditional go-to for creating water and stain resistance. When applied to fabric, these chemicals form an invisible, low-surface-tension barrier. Instead of soaking in, water beads up and rolls right off.

For swimwear manufacturers, PFAS finishes have historically served two functions: quick-dry marketing claims and stain resistance. The problem is that the compounds do not break down. Scientific research has linked certain PFAS to a range of adverse health effects. These include increased risk of kidney and testicular cancers, liver damage, immune system suppression, thyroid disease, and reproductive and developmental harm.

The "forever chemical" label is not marketing. The carbon-fluorine bond is one of the strongest in organic chemistry, making PFAS highly resistant to heat, water, oil, and chemical reactions. These properties are what originally made PFAS attractive for industrial and consumer applications. It is now also, however, the reason PFAS persist for so long in the environment. PFAS are commonly referred to as "forever chemicals" because they do not readily break down under natural environmental conditions.

Why swimwear sits in a unique risk category

Swimwear presents a distinct exposure profile compared to other apparel. The garment sits directly against highly vascularized skin, often for hours at a time. The groin, inner thigh, and abdominal regions are proximate to hormone-sensitive reproductive tissues. Heat, moisture, and chlorine exposure can potentially alter how fabric finishes interact with skin.

Synthetic fabrics like nylon and spandex, which are derived from petrochemicals, are used for optimum stretch and breathability. These materials are engineered for high-performance movement, but many of them are unfortunately finished with chemical treatments that can include PFAS. The effects of this can be even more harmful since our workout clothing sits tight against our largest organ (our skin) with our pores wide open as we sweat, taking everything in.

Swimwear specifically compounds this risk because the fabric is worn wet. Most swimsuits are made with synthetic fabrics treated with chemical finishes, including PFAS used for water resistance and durability. Because swimwear sits directly against your skin for hours, those materials matter more than many people realize.

The chlorine problem and how it intersects with PFAS

Chlorine resistance is a legitimate engineering challenge in swimwear. Chlorine-resistant swimwear isn't a marketing term. It's a result of choosing materials engineered to hold up in chemically treated water. Chlorine attacks the bonds in spandex (elastane) fibers. That stretch you love? It's the first thing to go. Repeated exposure causes fabric to lose elasticity, discolor, and eventually break down.

The historical industry response was to add chemical finishes. But the path forward does not require PFAS. Foreverever® fabric is certified to be free of PFAS, BPA, and other dangerous chemicals. In addition, Foreverever® fabric is made in mills that meet Global Recycled Standards (GRS).

Chlorine resistance can be achieved through fiber selection rather than chemical treatment. PBT is the gold standard for chlorine resistance. PBT is a type of textured polyester that's quick-drying, stretchy, and doesn't degrade in chlorine the way spandex does. These blends are ideal for competitive swimwear and athletic swim lines.

"Chlorine attacks the bonds in spandex fibers. That stretch you love? It's the first thing to go."

The Miami swimwear scene and why this matters locally

Miami is the global center of gravity for swimwear. PARAISO Miami Swim Week® is the official Swimwear Fashion Week, held in Miami Beach and recognized globally as the leading platform for swim and resort wear. Featuring top designers, emerging brands, trade shows, and immersive experiences, PARAISO connects fashion, beauty, media, buyers, and culture.

Miami Swim Week 2026 will take place from May 27 to May 31 in Miami Beach, featuring runway shows, trade shows, industry events, "Next Impact" talks, branded beauty and fashion pop-up events, and wellness programs.

SwimShow is the world's largest and most prestigious trade show for swimwear and has established itself as a key industry event since its inception in 1982. It takes place twice a year at the Miami Beach Convention Center and brings together an exclusive selection of industry professionals, including buyers, designers, retailers, and decision-makers from the international fashion scene. The event is organized by the Swimwear Association of Florida.

For founders based in Miami, the regulatory shift creates both risk and opportunity. If you are showing at SwimShow or PARAISO in May or June 2026, your buyers will increasingly be asking about PFAS status. Retailers selling into California and New York need documentation. The brands that solve this first win shelf space.

A worked example: reformulating a Miami-based swimwear line

Consider a hypothetical founder, Elena, who launched a swimwear brand in Miami's Design District two years ago. Her current fabric spec is a standard nylon-spandex blend with a DWR (durable water repellent) finish sourced from a Fujian mill. The DWR finish almost certainly contains PFAS.

Here is what Elena's reformulation path looks like:

Step 1: Request a chemical disclosure from the current factory. Ask specifically whether the fabric or any applied finish contains intentionally added PFAS or total organic fluorine above 100 ppm. California law prohibits manufacturing, distributing, or selling any new textile articles that contain either intentionally added PFAS or levels of total organic fluorine that exceed 100 ppm (which will be reduced to 50 ppm by January 1, 2027).

Step 2: Identify chlorine-resistant base fabrics that do not require PFAS finishes. Standard Lycra (spandex) breaks down quickly in chlorine, but Xtra Life Lycra® was engineered to resist degradation up to 5-10 times longer. It's not as tough as PBT, but it's ideal for brands that want sleek, flexible designs with extended wear.

Step 3: Source OEKO-TEX 100 certified fabric. The OEKO-TEX Standard 100 certification bans and/or limits intentionally-added toxic chemicals like PFAS, lead, azo-based dyes, bisphenols, phthalates, and more. This certification is the fastest way to demonstrate compliance to retailers and does not require you to conduct independent testing.

Step 4: Consider the stretch architecture. At Ohzehn, we built our fabric system around bio-based nylon and bio-based stretch fiber specifically to avoid the endocrine disruptor profile of conventional swimwear. But even within petroleum-based systems, you can reduce risk by selecting PBT blends and avoiding chemical finishes entirely.

Step 5: Update your labeling and marketing claims. Remove any "quick-dry" or "water-resistant" language that implies a DWR treatment unless you can document a PFAS-free alternative.

What to ask your factory before your next production run

These are the questions that separate compliant brands from those that will face enforcement:

• Does this fabric contain any intentionally added PFAS?
• What is the total organic fluorine level in ppm?
• Is the fabric OEKO-TEX 100 certified? Can you provide the certificate number?
• What chemical finishes are applied after knitting?
• Is the chlorine resistance achieved through fiber selection (e.g., PBT, Xtra Life Lycra) or through an applied finish?
• Can you provide a technical data sheet showing the fabric composition and any treatment chemicals?

If your factory cannot answer these questions, you have two options: find a new factory, or accept that you are taking on regulatory risk.

The certification stack that actually matters for swimwear

Not all certifications are equal. Here is what to prioritize:

OEKO-TEX Standard 100: OEKO-TEX is a third-party certification that tests a finished product for a variety of toxic chemicals. The certification is not totally perfect, but I still think it's worth looking for, especially if you're buying something plastic-based. The OEKO-TEX Standard 100 certification bans and/or limits intentionally-added toxic chemicals like PFAS, lead, azo-based dyes, bisphenols, phthalates, and more.

Global Recycled Standard (GRS): Relevant if you are using recycled nylon (ECONYL or similar). Does not directly address PFAS but signals supply chain transparency.

Bluesign: Tests for a broader range of chemicals throughout the production process. More rigorous than OEKO-TEX for environmental impact but less commonly available in swimwear mills.

What certifications do not tell you

Certifications are a floor, not a ceiling. OEKO-TEX 100 limits PFAS but does not require zero. If you want to make a "PFAS-free" marketing claim, you need either explicit factory documentation or independent lab testing showing non-detect levels.

The bio-based alternative path

The innovation isn't coming from a single magic bullet, but from a smarter, more holistic approach to design and material science. Modern PFAS-free period products achieve their performance through a combination of strategies: Advanced Weave Technology. Instead of relying on a chemical coating, many new fabrics use incredibly dense and tight weaves. The physical structure of the fabric itself is engineered to be water-resistant, minimizing the need for chemical treatments.

This approach, building performance into fiber architecture rather than applying it as a chemical afterthought, is the direction the industry is moving. Bio-based nylon derived from castor oil, corn, or agricultural waste can be engineered to provide stretch, chlorine resistance, and shape retention without the endocrine disruptor profile of conventional petroleum-based synthetics with fluorinated finishes.

"Instead of relying on a chemical coating, many new fabrics use incredibly dense and tight weaves. The physical structure of the fabric itself is engineered to be water-resistant."

The sourcing geography question

Miami's proximity to Latin American manufacturing clusters creates options that brands on the West Coast do not have. Colombia, in particular, has developed significant swimwear manufacturing capacity with shorter lead times than China. Several mills in Medellín have already reformulated to PFAS-free specs to serve the European market, where PFAS restrictions are even more aggressive.

For brands sourcing from China, the port logistics through PortMiami remain competitive for swimwear given the relatively high value-to-weight ratio of the product. But the compliance burden now sits with you. Chinese mills will manufacture to spec. They will not proactively reformulate unless you require it.

The regulatory trajectory through 2028

On March 19, 2026, the Congressional Record of the U.S. Senate published Bill S.4153, the Forever Chemical Regulation and Accountability Act of 2026. The bill proposes a comprehensive phase-out of per- and polyfluoroalkyl substances (PFAS) and the establishment of a regulatory framework. Manufacturers and users must completely phase out non-essential uses within 10 years of the Act's effective date.

This is federal legislation, not state. If it passes, the current patchwork of state laws becomes a national standard. Swimwear would almost certainly be classified as a "non-essential use" of PFAS.

By January 1, 2027, no person shall sell any new apparel containing PFAS at or above levels to be established by the state, regardless of whether PFAS was intentionally added. By January 1, 2028, the current exception for outdoor apparel for severe wet conditions will be phased out.

The trajectory is clear. Reformulate now, or reformulate under pressure later.

What this means for your next development cycle

If you are a swimwear founder preparing for Miami Swim Week 2026 or planning your 2027 line, here is your action list:

• Audit your current fabric spec for PFAS content
• Request OEKO-TEX 100 certificates from your mill
• Specify chlorine resistance through fiber selection (PBT, Xtra Life Lycra) rather than finishes
• Remove any marketing language that implies DWR treatment unless you can document PFAS-free chemistry
• Update your retailer sell sheets with compliance documentation
• Consider bio-based alternatives for differentiation and risk reduction

The brands that treat this as a sourcing opportunity rather than a compliance burden will win. The swimwear consumer increasingly cares about what sits against their skin. The regulatory environment is simply catching up to the science.

Fabric is not neutral. It is part of your biological environment. The swimwear industry built on PFAS finishes is ending. What replaces it is up to the founders who reformulate first.

Dougie Taylor

Co-Founder, Ohzehn Textiles · Building plastic-free performance apparel