“There are 25 billion pairs of running shoes made every year – enough to go round the earth 300 times – and most made from plastic,” says Angela Terry, an environmental scientist and founder of consumer advice company One House. 

“The big brands like to talk about their social purpose. But every trainer has 63 different component parts, from soles to laces, to the panelling on the sides, then they take 360 processing steps for assembly,” she explains.

“Most are made from polyurethane, nylon or latex, which are fossil fuel products, plus each of the separate elements is mass produced in 63 different factories in far-flung parts of Asia, and each has a supply chain of its own.”

It’s indisputable that the demographics diverge. An Opinium poll published last year found that half of people over 55 shop locally, buy fewer clothes, which last longer, and try to avoid single-use plastics.

By contrast only about a quarter of those aged 18-34 do the same and only 16 per cent of 18-34-year-olds buy seasonal produce, compared with 35 per cent of the over-55s. Then again, older people are more likely to own cars and take long-haul holidays.

But when it comes to adjusting the mindset of young people, Terry believes transparency and information rather than shame or guilt are the keys to conversion.

“In the words of the UN, we need rapid, far-reaching, unprecedented change across the whole of society,” she says. “In order to do that, the generations must pull together, not engage in the blame game. There’s far too much at stake to leave anyone behind.”

Let us hope that Generation Greenwash agrees.