An entrepreneur is launching 100% biodegradable clothing made from seaweed fibre which he hopes to make available as blank garments for decorators.

Adam Costello has unveiled a range of four T-shirts made of SeaCell – a patented fibre manufactured from Bladderwrack seaweed – to sell with his own designs through his business, Inland Sea.

However, he hopes that the seaweed fibre will appeal to other garment printers and retailers, leading to enough demand to make it cost-effective for him to supply blanks for their own designs.

“As well as our own line of garments, we plan to work alongside other independent ethical clothing brands to create and sell their own clothing ranges using seaweed fibre,” Adam said.

He has approached decorators and other independents but, as the fibre is little known, there is not yet enough demand to bring the cost per unit down enough to make it feasible. Inland Sea is selling its first “SeaBlend” T-shirts at £34.99 each via its website.

“At this stage, I am trying to raise awareness of seaweed fibre so demand goes higher and we can reduce the cost of the T-shirts. We would love to set up a supply chain for the T-shirts but we have to get the demand first.”

It is “massively early days”, Adam adds. Inland Sea’s first batch of T-shirts – available in two unisex and two women’s styles – have arrived only this month from the manufacturer in Lithuania – Utenos Trikotažas, a clothing producer certified by Greenpeace.

He added that the seaweed fibre creates a high-quality garment, with no limitations on colours including pure white garments.

Inland Sea has also found other ways to be sustainable across the business from carbon-neutral shipping to supplying its garments in 100% biodegradable packaging such as bags made from corn.

Adam started Inland Sea, based in Macclesfield in Cheshire, in 2017 to sell sustainable clothing made from recycled plastic bottles – an alternative to polyester which is harmful to the environment. He was concerned about the amount of plastic polluting the planet, much of which ends up in the sea.

He became excited about the potential of seaweed after discovering it is a mass absorber of CO2. Seaweed grows at an incredible rate, especially compared to trees, which means it absorbs CO2 from the atmosphere more quickly.

“Seaweed is a realistic solution to the climate crisis, and we want to bring this to the government’s attention – as a viable answer for helping to tackle the climate emergency.

“The average person in the UK produces 12kg of CO2 per day. By establishing seaweed farms here, we can offset huge amounts of carbon. Around 4,000kg of CO2 could be absorbed per day, per seaweed farm. That’s the equivalent of saving the emissions emitted from four return flights from London to New York.”

Developed by Smartfiber in Germany, SeaCell is manufactured using Bladderwrack, a type of seaweed commonly found in Atlantic oceans. It is seeded on ropes until it is ready to be harvested.

The fibre is made using environmentally friendly technology. The production process generates energy and recovers key parts of the raw materials by embedding the seaweed firmly within a natural fibre. This ensures the positive properties of the seaweed are permanently preserved, even after multiple washes.

“It is one of the greenest materials ever made and is 100% biodegradable,” Adam added. “By collaborating with retailers across the country, we can lead the way with sustainably-produced fashion.”

He used Kickstarter to raise more than £14,000 to develop his first SeaCell T-shirts. He has also partnered with Car-y-Mor Seaweed Farm in Pembrokeshire to invest back into UK seaweed production.