While many who buy faux leather often think of themselves as ethical buyers, the material could be polluting the oceans and killing fish, according to a BBC expert.

Patrick Grant, creative director of Saville Row tailors Norton & Sons, said 'ethical' designers like Stella McCartney who promote the use of plastic alternatives to leather are causing micro-plastics to enter our water systems.

The Great British Sewing Bee host said the designer is helping make man-made fibres fashionable, which could cause pollution.

"Eighteen years ago, she had been telling people to switch from leather to polyurethane and now the fish have it inside them," he told the Daily Mail.

Grant, who studied materials science at the University of Leeds, suggested: "Maybe we should eat less meat, but we do eat meat, so we might as well use the hides of the cows we eat rather than kill our fish."