From algae-based couture to kelp-derived yarns, fashion’s next material frontier is emerging from the ocean floor.
In September 2024, Keel Labs introduced its seaweed-based fiber Kelsun at the Stella McCartney Sustainable Materials Market during Paris Fashion Week — a showcase that featured next-generation innovators in bio-based design, from regenerative wool to ocean-derived yarns. The presentation marked a shift for seaweed material, moving it from a concept confined to biotech labs into a tangible textile on luxury’s main stage.
By mid-2025, the momentum had deepened. In Amsterdam, Iris van Herpen unveiled a couture gown composed of 125 million living algae, a collaboration between fashion engineers and marine biologists exploring how living organisms could shape future materials. Researchers in Europe advanced SeaWeave, an initiative transforming red and brown seaweed — fast-growing and regenerative — into fiber and natural dyes intended for large-scale textile use.
Brands and material researchers are aligning toward three key functional fronts: feedstocks that regenerate rapidly (seaweed biomass), coatings that bond in wet or marine-adjacent contexts (mussel-foot-protein mimics), and structural fibers that heal, regulate temperature or shed micro-plastics differently (squid-ring-teeth analogues). The performance rhetoric is clear: better moisture management, fewer chemical finishes, reduced micro-fibers, advanced wearability. Yet the ecological ledger remains ambiguous.
Seaweed can reduce the amount of cotton, trees, or petroleum used, according to author Alden Wicker. She says that can reduce the environmental impact of the shirt. But, she cautioned last year, “it’s not replacing polyester, nylon, acrylic, or spandex any time soon.”
The central question becomes: when a luxury house says “ocean-inspired” or “marine-derived,” does that guarantee ocean-friendly outcomes? Or does the scale-up of feedstocks, processing, chemicals, shipping, and finishing move the burden from one ecosystem to another?
Materials in motion: from seaweed to showroom
The first wave of marine biomimicry in textiles lies in seaweed-based fibers. “Seaweed grows abundantly in its natural habitat, and ours is harvested through a gentle, regenerative process, leaving its ecological value retained,” ADr. Amanda Parkes, Chief Innovation Officer at Pangaia, told Vogue. “The resulting fiber is completely biodegradable.”
This promise is compelling: seaweed incurs no arable land, minimal fresh-water irrigation, and integrates into closed-loop cellulose blends such as SeaCell or emerging proprietary fibers. Early data suggest seaweed textiles absorb carbon dioxide, require lower chemical loading, and reduce microplastic risk.
A research team at MIT found that mussels are able to deposit materials that adhere to wet surfaces in “seconds to minutes.” The research team found that these natural materials do better than existing commercialized adhesives, “specifically at sticking to wet and underwater surfaces, which has been a longstanding technical challenge.”
What that means for apparel: coatings or finishes that bond robustly under washing or exposure, reduce the need for fluorinated water-repellent chemistries, and potentially curb micro-fiber shedding. A broader survey of bio-inspired adhesives reviewed how aquatic organisms (mussels, barnacles) “can achieve rapid and robust attachment to almost all materials underwater” and how researchers aim to apply that to textile finishes.
On structural fibers, the framework is no less innovative: research into squid-ring-teeth proteins and other marine-inspired filament systems points to materials that repair themselves or adapt dynamically. For example, a materials engineering review of biomimicry for textiles observed that the natural world provides “excellent examples” of functional systems built with a handful of materials. “There are numerous examples of functional surfaces, fibrous structures, structural colours, self-healing, thermal insulation, etc., which offer important lessons for the textile products of the future,” the researchers noted.
In her 2021 collaboration with designer Phillip Lim, Charlotte McCurdy’s algae-sequin dress used macro-algae polymer sequins and SeaCell mesh — a symbolic pivot from petroleum-derived textiles to marine-biomass alternatives. “I come from thinking about formal sustainability strategy, but then I realized that the real gap and the real challenge we had was in creating visions of workable, livable futures, so that we could have a collective vision we could pull towards as a society,” McCurdy said in a statement. “that’s really creative work.”
Scale, sourcing, and standards
Though the materials read like innovation headlines, the real business of scaling remains complex. The SeaWeave project spells this out: “The fashion industry currently relies heavily on synthetic fibers and harmful dyes that contribute to ocean pollution, while most natural alternatives depend on farming that requires large amounts of land and water.”
Seaweed offers promise, but not without infrastructure. Aerated farms, coastal rope systems, nutrient flows, marine permits, harvesting logistics, and processing to textile-grade fiber all add cost and complexity. From the finishing side, while mussel-inspired adhesives show “exceptional underwater adhesion strength” in lab contexts, commercial textile production remains cautious.
Brands that challenge their performance claims against such criteria may differentiate themselves from greenwash. McCurdy noted that the transition is not just technical, but cultural: “The idea of sustainability in fashion is still trapped within an industrialisation framework — it’s about using fewer fossil fuels, or in a different way, and that’s not going to work.”
The most provocative dimension of marine biomimicry in fashion is not the runway splash but what it means for aquatic ecosystems. If a fiber is seaweed-based but harvested unsustainably, or a coating is mussel-inspired but processed via heavy chemical regimes, the net effect may shift harm rather than reduce it.
Still, the benefits are real. Seaweed aquaculture absorbs nutrients, sequesters carbon dioxide, and can provide habitat for fish, crustaceans, and shellfish. As the CFDA notes, seaweed plays a role in bio-sequestration of CO₂, nutrient-pollution mitigation, and increasing habitat for coastal aquatic species.
Yet the rebound risks are real. Large-scale harvesting of wild kelp forests can damage ecosystems, alter sediment flows, and reduce biodiversity. Scaling up remains a challenge due to high costs, inconsistent supply, and insufficient infrastructure in affected areas.
Finishing and end-of-life matter. If a so-called ocean-inspired fabric still uses petrochemical finishes, shipping via long-haul carbon-intensive logistics, or ends up in landfills rather than marine-safe degradation, then the advantages shrink.
Over the next eighteen months, tracking will tell as brands publish publicly accessible LCAs for marine-biomass fibers, adhesives, and finishes. Early references to “marine-bio certified,” “aquaculture-trace,” “micro-fiber verified,” and “marine-safe biodegradation” will be indicators. But, as McCurdy noted on the Clever Podcast, “We’re in a place where it’s not enough to sustain,” she said. “We need to be in a place where we are actively repairing and undoing the harm, if we’re going to have a liveable future.”
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