How Do Denim Jeans Cause Pollution?

Denim jeans are among the most popular articles of clothing on the planet. 4.5 billion pairs of them were sold in 2018 alone, meaning that at any given moment, approximately half of the entire global population are wearing these convenient, hard-wearing and stylish trousers. But what is the environmental impact of denim jeans?

A new study from scientists in Canada has discovered that not only are there significantly undesirable environmental effects from the manufacturing process of jeans, but that they continue to pollute the atmosphere for their entire lifespan. That’s because the fibres contained within the denim can break down into highly dangerous microplastics, which find their way into the natural environment and end up in beauty hotspots such as the Great Lakes of North America or even as far away as the Arctic Circle.

Damaging at all stages of life

To begin with, jeans consume a lot of resources. In order to grow sufficient cotton to create just one pair of denim trousers, 1,500 gallons of water are consumed. Meanwhile, the blue colouring is created through the use of a synthetic indigo dye, which is also damaging to the environment.

Once the jeans have been finished and shipped out to retailers for sale (in itself a process incurring significant emissions of greenhouse gases), the jeans are then bought and taken home by the consumer. But their polluting ways do not end here – each time they’re washed, they release a plethora of chemicals and microfibres into the environment. Indeed, the research revealed that just one wash could be responsible for the release of 50,000 individual microfibres.

Finally, once the jeans have become too torn or too stained to be of further use, they must be disposed of. However, the presence of metal zips, rivets and buttons means that they’re very difficult to recycle. As a result, the vast majority of jeans end up in landfill, further polluting the planet.

Microfibres the real culprit

By far the most damaging stage of their life cycle is the one in which they are used and washed regularly by their owner. When not escaping into the air and contaminating our airways, microfibres most commonly end up in our rivers, lakes and oceans.

Those were exactly the findings of the Canadian study, which detected traces of denim microfibres in the Great Lakes of the USA and Canada, the suburban lakes of Ontario and even the Arctic Archipelago belonging to Canada. They weren’t found in trifling concentrations, either. In fact, denim microfibres accounted for 23% of those found in sediments in the Great Lakes, 12% in the Ontario lakes and 20% in the Arctic location.

It’s not yet known exactly what kind of impact this contamination is likely to have on the native flora and fauna, though the researchers did discover a single microfibre in the belly of a rainbow smelt fish in the Great Lakes. In any case, it’s likely that even though you might never make it to the Arctic during your lifetime, there’s a decent chance your jeans will.