We have all been there before: we find a piece of clothing in our wardrobe we don’t wear anymore and decide to let go of it. But what happens to our clothes when we don’t want them anymore, especially the ones that can’t be sold or donated because they are simply too worn out to find a second home?
Unfortunately, only 20% of discarded textiles are recycled or find a purpose as construction insulation, carpet padding or industrial rags. The other 80% are doomed for landfills. And that leaves the question: what happens to our clothes once they end up in landfills, and how long does it take for them to disintegrate completely? Or is there anything we can do to save old textiles from landfills?
To answer this question, we need to have a look at the different types of fibers our clothes can be made from. All fabrics can be characterized as either natural or synthetic fibers (or a blend of the two), and their end-of-life scenarios differ significantly.
Biodegradability of Natural Fibers
Natural fibers are obtained from plants (such as cotton, hemp, linen, etc.) animals (such as different types of wool), or insects (such as silk). Like anything designed by nature, natural fibers slowly disappear back into the earth at the end of their life. A T-Shirt made from 100% cotton will decompose within a few months, and pure linen can biodegrade in as little as two weeks, while some natural fibers may take a bit longer. Depending on the blend, for example, wool may take between 1 and 5 years to decompose.
Biodegradability of Synthetic & Semi-Synthetic Fibers
Synthetic fibers, like polyester, nylon and spandex, are made of synthetic materials, usually formed through chemical processes. Since these materials are made from polymers found in natural gas and the by-products of petroleum, synthetic fibers are not biodegradable. These textiles can essentially be compared to plastic and although they will break down into smaller pieces over time, they are likely to sit in landfills for up to 200 years before they decompose fully.
Semi-synthetic fibers are also created through chemical processes, but they are made from natural materials. Most semi-synthetic materials are generated from cellulose, such as TENCEL™ as well as rayon, which is also known as viscose. When buried in soil, semi-synthetic fibers can take between a few weeks and a few months to biodegrade.
Other Factors Impacting Biodegradability
But there are other factors that impact how long it takes for discarded clothes to decompose fully, including how the fiber of the garment is woven, or whether it’s blended with another fiber. For example, the German Hohenstein Institute, which awards biodegradability certifications to products by evaluating how quickly they break down in soil, found that non-woven cotton disappeared completely within 28 days. Meanwhile, woven cotton and cotton/polyester mixes did not break down fully within the testing period. And it’s also important to note that these results don’t necessarily reflect what happens to our clothes in landfills, since soil composition and temperature both play a big role in biodegradation.
Preventing Textile Waste
What most people tend to forget is the huge toll our clothes take on the planet while they’re decomposing in landfills. The decomposition process of textiles generates greenhouse methane gases and releases toxic chemicals and dyes into the groundwater and our soil.
But the textiles that are rotting away in landfills are not only completely unwearable clothes; a large portion actually could have been reworn or recycled. According to ThredUp, 64% of the 32 billion garments produced each year end up in landfill. Right now, textile recycling is costly and we have a long way to go until advanced methods are put into mainstream practice. So, what can we do to save our clothing from landfills?
→ Commit to buying less & better
The simplest way to avoid textile waste is to commit to buying less in general, and utilizing other ways of enjoying fashion, for example through clothing rental services or clothes swaps. Choosing high-quality garments and materials that are made to last and supporting circularity-minded brands are other ways to prevent textile waste.
→ Dispose of unwanted textiles responsibly
Since the future of our donated clothes is uncertain, selling unwanted clothes on platforms like Facebook Marketplace, Vinted, Depop or Shpock is a safer way to give them a new home. Old clothes that can’t be worn anymore could be repurposed as cleaning rags, turned into pet toys and other crafty projects, or donated to a textile recycler near you.
If you want to help us close the loop and are interested in selling or buying our clothing second-hand, feel free to join The Slow Label Collective - a space for a community of like-minded people, committed to learning more about sustainability and discussing topics around fair fashion and slow living.