Sustainability academic Mark Sumner follows a T-shirt from cotton field to landfill to illustrate the true cost of fast fashion.
Consider an item of clothing we’re all likely to wear at some point – the T-shirt – the product of an industry responsible for 10 percent of global CO2 emissions.
Depending on the brand of T-shirt you’re wearing, you could be contributing to these emissions and a long list of other environmental and social harms. But to really understand these impacts, we need to explire the supply chain that creates them.
Spinning a yarn
Most T-shirts are made from cotton, which is grown in 80 countries by 25 million farmers who produced a total of 25.9 million tonnes of fifibre between 2018 and 2019. Conventional cotton farming consumes six percent of the world’s pesticides, even though it only uses 2.4 percent of the world’s land. These chemicals control pests like the pink bollworm, but they can also poison other wildlife and people.
Farmers tend to use large amounts of synthetic fertiliser to maximise the amount of cotton they grow, which can degrade soil and pollute rivers.
More than 70 percent of global cotton production comes from irrigated farms and it takes one-and-a-half Olympic swimming pools of water to grow one tonne of cotton. Your T-shirt could have used 7000 litres of water just to grow the cotton it’s made from. That’s a lot of water for one T-shirt, especially when you consider the fact that cotton is a crop that tends to be grown in regions plagued by drought. The farmer may have only 10 or 20 litres of water a day for washing, cleaning and cooking.
But the negative impacts only begin with growing the fibres. The cotton has to be spun into yarn, which uses lots of energy and is the second-highest source of carbon pollution across the T-shirt’s life cycle, after the dyeing process.
The cotton yarn is then knitted into the fabric that makes the T-shirt. Globally, this process generates an estimated 394 million tonnes of CO2 per year.
Next, colour is added to the fabric. This can be done in many different ways, but all rely on fresh water, which may become contaminated with tiny fibres or chemicals harmful to animals and plants. In some cases, this water is discharged directly into the environment without treatment. In Cambodia, for example, where clothing comprises 88 percent of industrial manufacturing, the fashion industry is responsible for 60 percent of water pollution.
The dyeing process uses lots of energy to heat the water, as most dye reactions occur at 60°C or higher. The coloured fabric then has to be washed and dried to prepare it for the final stage: garment-making. Overall, it takes about 2.6kg of CO2 to produce a T-shirt – the equivalent of driving 14km in a standard petrol-driven car.
Transporting the T-shirt to your house accounts for less than one percent of the garment’s total emissions. But once there, it consumes energy, water and chemicals. Washing, ironing and drying clothes represents one-third of the overall climate impact of clothing. Synthetic clothes, made of materials like polyester, generate tiny plastic fibres when washed, which eventually flow into rivers and the sea. Research suggests that synthetic fabrics are responsible for up to 35 percent of all the microplastics polluting the ocean.
Sadly, the average number of times a garment is worn before being thrown away is falling. In the UK, more than £40 billion (NZ$80 billion) worth of clothing sits at the back of wardrobes. Across the world, millions of tonnes of clothing ends up in landfill each year. Often these garments still have plenty of life in them if they are given the chance – 90 percent of donated clothes are suitable for sale in UK charity shops. But this relies on consumers saving old clothes from being thrown in the bin.
It’s a myth that fast fashion clothing is necessarily poor quality. Many brands do create durable products, some lasting twice as long as designer label equivalents that are up to10 times more expensive, according to one study. A growing number of businesses are trying to minimise the environmental impact of their clothes. Some UK brands have begun sourcing cotton which is less reliant on pesticides, synthetic fertilisers and consumes less water. Enough high-quality cotton can be grown to meet current demand with much less water and pesticides.
Cold pad batch dyeing uses up to 50 percent less water, energy and chemicals than standard processes and produces much less waste. Voluntary initiatives, such as the Sustainable Clothing Action Plan, are trying to set minimum standards for quality across the industry.
You can make a difference too. Buying from responsible brands is a good start, as is only washing the garment when it really needs it. Once you’re finished with your clothes, giving them to clothing charities offers them a second life and makes fashion overall much greener.
Hopefully, knowing more about the vast effort and resources that go into making our clothes can help people make better choices as well. Before throwing old clothes out, remember the long and costly journey your T-shirt took from cotton to wardrobe, and think again.
5 ways to lower your cotton impact
- Buy fewer garments. This is probably the number one thing we can all do.
- When you do buy, look for more sustainable cotton: ideally recycled, or organic. Many labels at all price points are including this in their ranges now, or even better, using only sustainable cotton. Look for a certification licence number on any claims. And bonus points for outlets committed to re-using fabric.
- Once that garment is yours, look after it. Launder it only when really necessary; fix undone hems, seams or rips rather than throwing it away.
- If you’re finished with the garment and it’s still in good condition, launder and donate it.
- If it’s too worn out, can you use it for something else? Old T-shirts make great soft cleaning cloths, for example.