Scientists found untreated wool biodegraded at 20.3 per cent the rate of the pulp and the machine-washable wool biodegraded more than three times as quickly, at a rate of 67.3 per cent – the fastest of all fabrics.

At the tail-end was Nylon, biodegrading at a rate of just 0.8 percent, followed by polypropylene and polyester.

“Our research into wool and microplastics began back in 2016 when we investigated the current state of knowledge concerning microplastic pollution, focussing on microfibres from textiles,” explains The Woolmark Company Managing Director Stuart McCullough. “This initial body of research began the process of improving methodological development to account for microfibre release during the use phase in the Lifecycle Assessment of clothing.

“This latest scientific study is a significant addition to the body of research investigating the damage certain textiles cause to our environment. Wool has long been heralded the original eco fibre, but concerns had been raised about the machine-washable finish applied to wool and whether it added to the microplastic problem, so we wanted to clarify that issue. During these ever-changing troubled times it’s important to consider how well-intentioned consumers can make purchasing decisions that help look after the health of the environment. Choosing natural fibres, such as Merino wool is an important place to start.”