Each year the global apparel industry churns out more than 100 billion garments – numbers so vast they almost defy comprehension. Behind every piece of fabric and every new fashion trend lies an enormous social and environmental footprint: one in every eight workers on the planet earns a living in fashion, and the industry itself is worth roughly $2 trillion. Yet that economic force comes with heavy costs. Fashion ranks as the world’s second-largest consumer of water and already accounts for up to 8 % of global carbon emissions, a share that could soar toward 26 % if current production and consumption patterns persist. The materials we’ve come to take for granted aren’t innocent either: 60 % of all textiles are made from plastics, a legacy of the post–World War II boom in synthetic fibers, whose global production has more than doubled in the last two decades. Roughly 1 % of the world’s crude oil now goes into making these fibers, and the hidden consequence ripples through the oceans. Each year an estimated 500 000 tons of microfibers wash off our clothes into the sea, the equivalent of 50 billion plastic bottles. On land, up to 20 % of wastewater pollution worldwide stems from dyeing and finishing clothes, yet at the end of their short lifespans, less than 1 % of textile materials are recycled back into new garments, and a mere 0.3 % of the 3.25 billion tons of resources used annually in textile production come from recycled inputs.
Beyond Plastic: The Rise of Marine Biomaterials
The past years have seen a steady increase in textiles made from recycled plastic, however, most recycled polyester is sourced from PET bottles being diverted from an established closed-loop bottle-to-bottle recycling system, effectively resulting in downcycling and a one-way ticket to landfill. Brands resorting to the use of recycled fishing nets or ocean plastic often look more sustainable on the outside, but cannot solve the issue of energy-intensive processing and microplastics wash-off. The handful of biosynthetic materials commercially available at the moment are made using starches, sugars, and lipids sourced from corn, sugar cane, sugar beets, and plant oils.
This is the backdrop against which ocean-derived biomaterials are beginning to offer a different story – one where fashion’s impact can be actively reduced rather than simply measured. Material scientists, fashion students, entrepreneurs and designers are beginning to rethink what we can use in our clothes, outerwear, furniture, and accessories. Using materials from the ocean is not a new idea: shells of clams and mussels have been used as decorative elements in high fashion, indigenous tribes turned fish skin into leather, and sequins and translucent raincoats made out of algae have already been spotted on the runway. But the biggest problem remains in designing textiles suitable for everyday use. I spoke to four of the people trying to tackle this challenge head-on.
“Our goal is to produce a T-shirt made from 100% seaweed.”
Katharina Nøkling-Eide is a research scientist trying to build on Europe’s long tradition of utilizing seaweed. As part of the SeaWeave project, she investigates how red and brown seaweed can be turned into innovative and sustainable fibers and dyes. The main advantage of using seaweed as a textile feedstock lies in the minimal input factors required to grow it – just nutrients naturally occurring in seawater, CO2, and light – compared to the freshwater and fertilizer-intensive cultivation of terrestrial crops such as cotton.
Seaweeds contain unique compounds such as alginates, carrageenan, and agar, so-called hydrocolloids. These naturally occurring polymers, already widely used as gelling agents, are now being explored as the basis for textile fibers. At the same time, pigments like fucoxanthin (brown) and phycobiliproteins (red, blue, or turquoise) could enable integrated biorefinery processes where both fibers and natural dyes are extracted from the same biomass.
The goal is ambitious: clothes made entirely from seaweed, making them fully biodegradable. Yet translating seaweed into textiles is far from straightforward. “One of the main challenges is the high ash content in seaweed, which can create difficulties during fiber processing, particularly in spinning,” Katharina explains. At the same time, the material’s high water content of up to 90 percent makes cheap and energy-efficient drying a critical bottleneck. Scaling will be fundamental: “To make a meaningful impact in the textile industry, production would need to reach several thousand tons of biomass.”, she emphasizes, noting that large-scale cultivation must be carefully managed to avoid environmental impacts such as nutrient depletion in the water column. One way to reduce this pressure is to make better use of existing resources, for example, by using by-products of kelp, that are discarded by the food industry. Done right, this expansion could not only limit environmental impact of textiles but also create new economic opportunities in coastal communities.
What if the fiber is already there?
Meanwhile, another idea on how to turn algae into fabric grew into a prize-winning project in Germany: AlgaTex wants to revolutionize the way algae are used and cultivated for the textile industry. Unlike projects such as SeaWeave, which extract polymers from seaweed, the AlgaTex project works with filamentous algae that “already grow in fiber-like structures,” explains doctoral researcher Atiqur Rahaman. By using the native biomass directly rather than breaking it down and rebuilding it, the team aims to simplify production and make algae-based textiles more competitive with existing materials.
However, translating this natural string-like structure into usable textiles remains challenging. “After drying, seaweed usually becomes hard and loses flexibility,” Atiqur explains, making it difficult to process into textiles without modification. Even so, the team’s research shows that native filamentous algae can be used directly as a textile fiber, highlighting their potential for future yarns and other functional materials.
The technology itself is advancing, but scaling remains tricky. “The textile processing technology has already been developed, but we still face a shortage of raw material,” Atiqur says. Cultivation methods and costs will therefore play a decisive role in determining how quickly these materials can move from laboratory experiments to everyday products. Where other seaweeds such as sugar kelp have a long tradition of being grown in simple commercial settings, filamentous algae require slightly more sophisticated culture setups. Without attachment surfaces and controlled water flow they tend to cluster into dense masses that reduce productivity. Transferring freshwater algae to marine environments or using species-specific photobioreactors could help overcome these limitations.
Making Clothes Durable: From Forever Chemicals to Safer Alternatives
While innovations in seaweed- and algae-based fibers are beginning to reshape what textiles can be made from, materials alone are only part of the equation. To function in everyday use – whether as rain jackets, activewear, or upholstery – textiles often rely on additional chemical treatments that provide water repellency, stain resistance, reduced flammability and durability.
For decades, these performance properties have been achieved using per- and polyfluoroalkyl substances (PFAS), a class of chemicals now under increasing scrutiny. Their widespread use ranging from textiles to food packaging and even phone screens dates back to 1938, when the invention of Teflon transformed household staples like the non-stick frying pan. But the same chemical stability that makes PFAS so useful has also earned them the label “forever chemicals”. They persist in the environment, in soil and water, accumulating in wildlife, and ultimately in the human body where they have been linked to a range of health concerns, including cancer, hormonal disruption, and fertility reduction. Despite growing awareness, PFAS remain deeply embedded in global supply chains, with a market valued at tens of billions of euros, strictly controlled by a small number of companies. At the same time, the long term cost of their negative impacts is projected to far exceed these benefits, prompting increasing regulatory pressure, particularly in the European Union, to phase out their use.
As a result, the search for safer alternatives is accelerating. This is where companies like Algae Scope come in, developing bio-based coatings that aim to deliver the same performance without the associated costs. This means tackling one of the most technically challenging problems in the textile industry: “PFAS combine multiple properties – water, oil, and fire resistance – in a way that is extremely difficult to replicate in a single, fully bio-based material,” explains CEO Natasha Yamamura. While alternatives exist for individual functions, matching this full performance spectrum remains rare.
Algae Scope’s approach can use any kind of seaweed: brown, red, or green. Their patented coating, currently developed as a powder, can be integrated into existing textile finishing processes and tailored depending on the application. While the powder can be formulated and used in all textiles, the focus, COO Alejandra Noren notes, is on functional and durable textiles – such as cruise ship or air plane interiors – where strict water- and fire-resistance standards apply. Rather than requiring entirely new infrastructure, the aim is compatibility: “The goal is not to reinvent manufacturing processes, but to fit into existing ones as seamlessly as possible.”
The material itself is derived from an abundant – and often overlooked – resource. In many seaweed-based industries, the majority of the biomass remains unused after extraction. “Up to 90–95% of seaweed biomass is currently left as residue,” Natasha says. “We’re turning that into a resource.” By tapping into these side streams, the company aims to avoid competing with food production or driving large-scale new cultivation. And the numbers are on their side: one of their Norwegian supplier factories alone currently produces around 30,000 tons of seaweed waste annually in wet weight, which can be turned into about 1000 tons of coating powder.
Still, bringing such a solution to market is more than a simple question of chemistry. Scaling production, tailoring formulations for different materials, and meeting certification standards all require significant investment. At the same time, industry adoption is uneven. While regulation is tightening in regions like Europe, global supply chains remain fragmented. “The transition away from PFAS won’t happen overnight – it will be gradual, with different industries adopting alternatives at different speeds.”
Can Better Materials Fix a Broken System?
So – are ocean-made clothes the future? The signs are promising but even the most sustainable materials cannot undo a culture built on overconsumption. A T-shirt made from seaweed still carries a footprint if it is worn only a handful of times. Perhaps the real shift is not just in what our clothes are made of, but in how we value them: wearing them longer, choosing them more carefully, and letting them return – eventually – without harm to the systems they came from.
An article by Kim-Isabelle Mayer, interview with Katharina Nøkling-Eide (SeaWeave), Atiqur Rahaman (AlgaTex), Natasha Yamamura and Alejandra Noren (Algae Scope)
Photo credits: Samuel Jerónimo (Unsplash), Jason Mayne/People Dispatch Twitter, Karen Chew (Unsplash), Anika de Klerk (Unsplash), Ben Kerckx (Pixabay), Claudio Schwarz (Unsplash), Digital Buggu (Pexels)