This claim that fast fashion contributes a huge amount of pollution and harms the environment is true.
According to an analysis from Business Insider, production of fast fashion adds 10% of the total global carbon emissions. With 85% of textiles going to dumps each year, and 500,000 microfibers being dumped into the ocean each year, fast fashion being dumped is worth the same as 50 billion plastic bottles.
Earth.Org Global Commons. (2026, February 3). The environmental impact of fast fashion, explained. Earth.Org. https://earth.org/fast-fashions-detrimental-effect-on-the-environment/
Not only does fast fashion cause pollution, but it also causes global warming. The decomposition process of dumped clothing releases methane. Methane, along with other harmful pollutants that are brought into the atmosphere, contribute to global warming. Clothing items that are being dumped take decades or centuries to decompose, making the amount stack up over time.
The Institute for Environmental Research and Education. (2025, June 30). Why is fast fashion bad for the environment? IERE. https://iere.org/why-is-fast-fashion-bad-for-the-environment/
Finally, the amount of water that is used to make the clothing is extremely high. It takes 2,700 liters of water to make one shirt made out of cotton. That is equivalent to around what one person drinks in two and a half years. This is harmful to the environment because valuable fresh water does not go where it is needed, but it is instead used to create more clothes, which become waste very quickly.
Stawarz, S. (2025, August 4). The hidden cost of fast fashion: A threat to land and water conservation. The Conservation Foundation. https://theconservationfoundation.org/the-cost-of-fast-fashion/