Fast fashion has some nasty side-effects, among them water and air pollution, and worker fatalities. It’s usually cotton in the dock. But a new report has revealed another, more unexpected, guilty fibre: viscose.

Traditionally sourced from wood pulp, viscose was seen as a popular ‘green choice’ and ‘fibre of the future’ for high-street labels and retailers such as H&M, Zara, ASOS and Tesco.

But unsustainable methods of production are marring viscose’s squeaky clean reputation. ‘Dirty Fashion’ – an investigative report by advocacy group Changing Markets – has exposed how factories in Indonesia, China and India are churning out toxic waste to meet growing demand.

‘Some of the world’s biggest brands are turning a blind eye to questionable practices within their supply chains,’ said Natasha Hurley, campaign manager at Changing Markets. ‘Shifting to more sustainable processes should be high on retailers’ agendas.’

At some production plants investigators found multiple cases of work-related deaths and increased incidences of cancer in nearby communities as a result of toxic water and air pollution.

Campaigners are asking retail companies to implement a zero-pollution policy across their supply chain, lawmakers to enforce stricter environmental policies and encouraging shoppers to buy only from retailers committed to sustainable sources.

Kelsi Farrington