The world's trusted guide to sustainable and ethical fashion

The world's trusted guide to sustainable and ethical fashion

Why, Exactly, Is Polyester So Bad for the Environment?

Updated in January 2021

Say the word polyester around a sustainable fashion advocate, and watch them recoil in disgust. Use a polyester-cotton blend in your eco-conscious collection, and you’ll be accused of greenwashing.

You can’t deny polyester has come a long way from the scratchy suits of the 1970s. It’s been refined and tweaked until you can get all sorts of textile doppelgangers out of it, from fake silk to fake suede and faux fur. It’s washable and hardy. It’s a performance textile, used in activewear, athleisure, and outdoor gear (yes, even high-end, eco-friendly outdoor gear). Of course, it’s also used in cheap, tacky, toxic clothing from dubious brands that advertise on Facebook. My point is: Polyester comes in so many forms and prices and uses, it’s hard to avoid it. 

But eco fashion influencers try, throwing the word polyester around as if it’s an epithet. Why do environmentalists and ethical influencers have such strong feelings about polyester? And is their ire warranted? Let’s go through their reasons.

1. Polyester encourages fashion overproduction and waste.

Polyester made up 52% of global fiber production in 2018, at 55 million metric tons produced annually, according to a presentation by Oerlikon at ITMA 2019 (cited in Textile Exchange’s 2019 Preferred Fiber and Materials Report). Cotton comes in a distant second.

Brands have gravitated toward polyester because it’s often a more affordable and easier textile to get ahold of than natural fibers. You just put in an order with one of the thousands of synthetic fiber mills around the world, it’s produced and then shipped to the cut-and-sew factory. That’s opposed to cotton, which can go through wild price swings due to drought, natural disasters, and political crises. Or animal fibers, which are difficult to standardize and industrialize without animal abuse being baked into the system.

You could say that polyester has been enabling the overproduction of fashion, in fact. Before polyester was discovered in the 1940s, our textile production was limited by the amount of land devoted to growing cotton and linen, or raising sheep and silkworms. Being able to produce polyester in a factory decoupled production from land area. According to McKinsey, between 2000 and 2014, global clothing production doubled. Not coincidentally, 2002 is when demand for polyester surpassed cotton. Most of that increased fashion production has been made possible by polyester.

2. Polyester is made from fossil fuels.

What you call polyester is technically polyethylene terephthalate or PET plastic molded into filaments that are then woven into fabric. It’s made in a chemical reaction between ethylene glycol and therephthalic acid, and these chemicals are derived from fossil fuels, air, and water.

In a perfect future world, where we’ve decarbonized our global economy and we’re putting carbon back in the ground instead of pulling it out, it would be hard to justify polyester, because it relies on pulling more oil and coal out of the ground.

3. Polyester can’t be recycled, yet.

Yes, there’s one Japanese factory operating at a commercial scale that will recycle their own polyester from Patagonia into fresh polyester. The rest of the global output of polyester can’t be recycled at a cost that is acceptable to fashion brands using today’s technology. Used textiles of pure cotton have value since it can be mechanically recycled, but as soon as you add polyester, recycling becomes much more complicated—the polyester must be kept from contaminating the salvaged cotton fibers. While there is some promising technology that could melt polyester out of polyester-cotton blends for recycling, we’re still far from building an efficient global system for collecting and sorting used polyester for recycling. As a result, pretty much all polyester and polyester-blend scraps in post-consumer fashion waste are going into the landfill, being incinerated, or washing into the ocean. Even if we do start collecting and recycling polyester, the PET degrades a little more during each loop. It can’t be recycled forever.

The story is a little better for polyester made from recycled PET plastic bottles, which many fashion companies have eagerly adopted for part or all of their polyester products. According to Textile Exchange, the market share of recycled polyester increased from around 8% of global polyester production in 2008 to around 16% in 2017. Unfortunately, when China stopped taking the world’s trash for recycling, the price of recycled polyester went up and its share of the market declined to 13% a year later. As long as petroleum is easier and cheaper to obtain than plastic bottles, recycled polyester will remain a niche product.

4. Polyester is not biodegradable, and can shed toxic microfibers.

While cotton, wool, and silk will completely biodegrade within a few months to a few years, as a plastic, polyester will take hundreds of years to completely biodegrade. Before that happens, however, it will degrade into little microfibers. These microfibers slough off certain types of clothes into the air when we are wearing them, and flow into our waterways from our washing machines. Recent research estimates that globally, “176,500 metric tons of synthetic microfibers — chiefly polyester and nylon —   are released every year.”

And we’re eating, breathing, and drinking them. It’s estimated we ingest a credit card’s worth of microplastic every week. This is dangerous for us and aquatic life, because these microfibers can attract carcinogenic toxins. These are carried into our bodies through the ingestion of microfibers, which can then lodge in our gut.

5. Polyester gets smelly.

I’ve spoken to a textile researcher about how different fibers interact with our bodies, and polyester is not great in that regard. While it’s billed as “sweat-wicking,” meaning it doesn’t get heavy when it gets wet like cotton does, after a few wears and washes, you’ll start to notice that it’s hanging on to your B.O. Or, even more embarrassing, that after a few hours in your synthetic yoga pants, your crotch has become quite aromatic.

For that reason, while I have some polyester workout clothes, I try to stick with cotton and merino wool undies and leggings, especially when I travel. This is anecdotal, but I just get itchy in polyester pants after a few hours. And ever since I stopped wearing synthetic yoga pants for more than the hour it takes to workout, I’ve noticed that my private parts are much happier for it. This isn’t just a lady thing, either. Once my husband got rid of his polyester socks and switched to merino wool (on the advice of his dermatologist) his feet became much happier, too.

Don’t Believe Everything You Hear About Polyester, However

There are a couple of myths around polyester that eco and wellness bloggers tend to promulgate, and while they sound scary, they’re not actually true.

1. Polyester is not harmful to your health.

I’ve been told by some well-meaning designers and bloggers that polyester is carcinogenic. Pure polyethylene terephthalate (PET) is not toxic at all. It’s when it is blended with other compounds, dyed, scoured, and finished that it starts accumulating chemical compounds that can affect your health, or the health of mill and garment workers. But this is true for all fabrics — organic silk could be toxic after it goes through the entire supply chain. There’s also a rumor that polyester made from recycled plastic bottles is toxic, in that it has endocrine disruptors that mess with your hormones. That’s not true either. I go into it here, but the short explanation is that to create polyester, you need pure, uncontaminated PET bottles.

2. Polyester production isn’t always more polluting than other fibers.

The other myth is that polyester always uses more water and creates more greenhouse gas emissions than natural fibers.

According to the Higg Index, polyester is better than cotton in some ways, and worse in others. It has a lower negative impact when it comes to water pollution, water scarcity, and chemistry. It has a higher negative impact when it comes to global warming and fossil fuel usage, but not by much. And for global warming specifically, it looks better than almost every other natural fabric, including hemp, linen, wool and silk. When it comes specifically to fossil fuel use, polyester is worse than almost every natural fabric, except for silk.

Now, Higg has its problems, so take that all with a grain of salt. One fair criticism is that polyester’s impacts are measured starting at the base chemicals, instead of at the extraction of fossil fuels, while cotton’s impact is measured at the point where the seed is planted. And other research puts the global warming impact of polyester higher than cotton.

In short, polyester is just average when it comes to environmental impacts during its production, and it depends a lot on how it’s made, rather than the polyester itself.

3. Polyester doesn’t fall apart quickly.

Now, I know where this comes from. A lot of super-cheap fashion is made of polyester. So when you buy something from Fashion Nova and it falls apart after three wears, you want to attribute that to the fabric. But that’s a problem with the seams and construction of the garment, not the textile itself. Textile researchers know that blending polyester in with a natural fiber can actually make a garment last longer, as Sandra Roos has pointed out to me. And a lot of expensive performance gear, which needs to last a long time under extreme conditions, is made using polyester. So that claim doesn’t hold up to scrutiny.

4. Some polyester textiles shed barely any microfibers.

Whenever we’re talking about polyester, in the next breath some rather scary figures about microfiber pollution are mentioned. (See above.) However, some polyester fashion is rather innocent of the charge.

“I think there are some nuances here that are really important,” Peter Ross, VP at the non-profit Ocean Wise, told WBUR in 2019. “Some polyester textiles shed a great deal and others do not… We know that polyester fleece sweaters can shed millions of fibers in a single load of laundry whereas some performance gear that is tightly woven, but it’s equally made up of 100 percent polyester, might not shed much at all.”

Textile consultant Mick Siddons explained it to me further. “In principle, if a continuous filament is not cropped, brushed, or abraded, it is physically impossible for it to shed.” He’s talking about fleece, faux fur, and other fluffy types of polyester fabric, while smooth polyester fabrics like those you find in yoga pants and performance jackets don’t have microfibers to shed. “Each fiber really is endless and the fibers are air tangled every few millimeters to stop the filaments separating. Even if the filament is broken it cannot come out unless it is broken again between mingle areas,” he says.

So you should only really worry about washing and wearing fluffy polyester clothing. Enjoy your yoga pants!


Yeah, polyester is not great. It’s part of a make-take-throwaway culture. It’s made from fossil fuels. It doesn’t biodegrade, and isn’t recycled. And it’s uncomfortable, especially for the ladies.

But sometimes, it’s the best choice for a high-quality or performance garment. If you’re a purist trying to get plastic completely out of your wardrobe, here are some tips to do so. But my recommendation is to be open to polyester when it’s warranted, and avoid it when a natural fiber alternative is available.

This post originally linked out to an old article from another blog. As it’s been five years, we decided it needed a complete refresh. The title and URL are the same, the contents are all new.


  • Alden Wicker

    Ruth Alden Wicker is the Founder and Editor-in-Chief of EcoCult. Along with growing EcoCult to be the leading international information hub for sustainable fashion, she also writes for publications including Vogue, The New York Times, Wired, The Cut, Vox, InStyle, Popular Science, Harper's Bazaar, Quartz, Inc. Magazine, Martha Stewart Living, Craftsmanship Quarterly, Refinery29, Narratively, and many more.

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