Two startups — Zeefier in the Netherlands and SeaDyes in Scotland — are producing natural textile dyes from seaweed, offering a non-toxic alternative to petroleum-derived dyes responsible for 20 percent of global industrial water pollution.
The label on your clothes tells you what the fabric is — cotton, linen, wool — but it never tells you where the color came from. That omission is, in practice, a significant one. Textile dyeing accounts for roughly 20 percent of global industrial water pollution, with an estimated 140,000 tonnes of synthetic dyes leaking into waterways each year.
The dyes responsible for your navy blazer, your red dress, your black jeans are largely petroleum-derived, often laced with heavy metals like copper, mercury, and chromium that don’t break down once they enter a watershed. Around 15 to 50 percent of azo dyes — among the most common in fashion — are discharged directly into wastewater because they fail to bond to the fibers at all. “Most synthetic dyes are not only bad for the environment,” Anne Boermans, co-founder of Dutch dye company Zeefier, said in a statement, “but also contain chemicals that are harmful to our health.”
Zeefier is one of two startups, along with SeaDyes, on opposite sides of the North Sea, that think seaweed can replace conventional dyes at scale. “There is so much seaweed, and it is used mostly for food,” says Boermans. “We realised it could also play an important role in the non‑food sector.”
Zeefier and the colors nobody expected from the oceans
Zeefier was launched by Dutch designer Nienke Hoogvliet and entrepreneur Boermans after Hoogvliet spent nearly a decade researching how different varieties of seaweed produce different pigments. “The colour palette is not what you expect,” Hoogvliet told Dezeen. “It’s not just boring greens and browns; there’s so much more, including purples, pinks, and oranges.”
The dyes are formulated as plug-and-play solutions, engineered to work in standard dye-house equipment without requiring industrial overhaul, and are compatible with cotton, wool, silk, linen, and viscose. Raw material comes from European sea farms, coastal wash-ups, and industrial side streams, keeping the supply chain local. Because seaweed requires no agricultural land, no fresh water, and no synthetic inputs to grow — and actively absorbs carbon — the upstream environmental cost is a fraction of conventional dye production.
This month, the European Commission’s Blue Economy program spotlighted Zeefier in a feature on ocean-based industrial innovation, following the company’s participation in the BlueInvest Investment Readiness program in 2025. The company has also been nominated for the King Willem I Award 2026 Plaque for Sustainable Entrepreneurship, the Netherlands’ most prominent recognition for business innovation.
SeaDyes and the science of growing a rainbow
Scotland’s SeaDyes is working on the same problem from a different coast. Founded in 2023 by marine scientist and biotech innovator Jessica Giannotti, the company uses blue biotechnology to gently extract pigments from seaweed — purples, magentas, reds, and browns so far, with a broader range in development — and convert them into dyes that function within existing production infrastructure.
“For the past decade, I have been combining art and science to create textiles and designs that celebrate and communicate the wonder of the ocean,” Giannotti said in a statement. “With SeaDyes we are taking that one step further, using seaweed to create a rainbow of vibrant colours that can be used by the fashion and textiles sector at large.”
“The work being done at SeaDyes represents a powerful step forward in rethinking how colour is created, with sustainability and environmental responsibility at the core,” Ian Laird, the firm’s newly appointed commercial champion, said in a statement.
The company recently secured £200,000 from Scottish Enterprise’s High Growth Spinout Programme — the second tranche of public funding following an initial £75,000 that brought Giannotti’s lab into residence at the James Hutton Institute’s Invergowrie campus. SeaDyes has engaged more than 100 potential customers and is now seeking additional private investment to move from prototype to commercial scale.
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