There are 25 billion pairs of running shoes made every year – enough to go round the earth 300 times – and most made from plastic. Hardly any of them are recyclable. Very few people realise that the mass production of beautifully designed sneakers puts them just behind aviation and shipping in terms of global emissions.
But that’s only part of the problem. The real issue is micro-plastics that you can’t see. We breathe and ingest them in all day long. They are everywhere, in the air, in the national parks, in the snow packs on the highest mountains and in giant columns in the sea. Plastic threatens fertility of animals and humans alike.
Alternatives? They exist.