LONDON — The sight of plastic pollution in the world's oceans is all too familiar. But now the ocean is fighting back. Shellfish, such as lobsters, could offer a solution to the scourge of single-use plastic thanks to a bio-polymer in their shells called chitin.
London-based startup The Shellworks is developing a method to transform the chitin from the shells of lobsters and other crustaceans — normally destined for the rubbish tip — into a novel bioplastic that's both biodegradable and recyclable.
"We started with lobster shells because it has the highest content of chitin; it makes up about 30 to 40 per cent of the shell. So for us that makes the most sense as well as it's an untapped waste stream," Shellworks co-founder Insiya Jafferjee told Reuters.
The shells are first pulverised in a blender before being broken down further in various solutions to extract the chitin.
"We take lobster shells, we crush them up and then we use an acid and alkali solution to strip away mineral and protein layers to get to the chitin nano-fibres. We can then add that chitosan powder to household vinegar and that gives us a bioplastics solution. And then we use that solution with our custom-made machines to form three dimensional things," explained co-founder Amir Afshar.
One of their experiments includes using a heated mould that's dipped into the gooey chitin mixture to make plant pots.
The Shellworks — made up of Jafferjee and Afshar, along with fellow founders Ed Jones and Andrew Edwards — are now testing chitin-based recipes for products traditionally made from single-use plastic, including the all-pervasive plastic shopping bag.
"We're trying to understand whether the material can withstand the pressures needed to become a viable alternative," said Mr Afshar, adding that the bioplastic has other useful properties too.
"It's antifungal and antibacterial which means that it would be really interesting for storing foods and at the end of life it's actually a non-polluting fertilizer. So even if you had a bag at home you could just chop it up thrown into a plant pot and it would just help them grow," he said.
The Shellworks research follows other attempts to use chitin for an alternative to plastic, including by chemical scientists at McGill University in Montreal who recently patented a method to make chitosan powder with a longer molecular chain, making it stronger.
Founded from a group project from the Royal College of Art and Imperial College London, the Shellworks is now looking for partners to take their small-scale research to the next level.
According to Ms Jafferjee, there are enough waste shells to make a serious dent on the UK's plastic use.
One London lobster chain with nine restaurants, she said, produces 375 tonnes of waste shells a year: "Chitin content-wise, that's 125,000 kilograms. And from that every year we could make about 7.5 million plastic bags."
In the year 2017-2018, the UK's seven main supermarket retailers sold 1.04 billion single-use plastic bags, a figure that reflects a downward trend since charges were introduced.
Globally, some 500 billion disposable plastic bags are used every year, according to the United Nations. Nearly a third of plastic packaging escapes waste collection systems, and at least 8 million tonnes of plastic leak into the oceans each year, smothering reefs and threatening marine life. REUTERS