6 Unsustainable Fabrics To Avoid

Last week I wrote about the 7 most sustainable fabrics that you can feel good about buying. Today, I cover the other side of the fashion spectrum: the 6 least sustainable fabrics that you should do your best to avoid. As you read this, keep in mind that no one is perfect; instead of beating yourself up for wearing clothes made of these unsustainable fabrics, do your best to avoid them in the future.

The 6 fabrics that are the worst for the environment include polyester, conventional cotton, viscose, nylon, acrylic, and spandex. In this guide, I get into the environmental impact of each of these fabrics so that you understand why they’re best avoided. I’ll also answer a question I see quite often: is fabric made from bamboo sustainable?

Whether you’re wondering how to lower your fashion footprint or just curious about the environmental impact of different fabrics, get ready to learn all about the least sustainable fabrics in the industry. Keep in mind, some of these fabrics are incredibly common and highly pervasive; it’s unlikely you’ll be able to avoid them entirely, but you can do your best to keep on the path towards this green lifestyle.

Photo by Rio Lecatompessy

Why should you care?

When it comes to changing your habits in order to lead a more sustainable life, there are few things you can do that are as effective as changing your relationship with fashion. As covered in my article about the 7 R’s of sustainable fashion, that starts with rethinking, refusing, and reducing your fashion consumption. More specifically, it means seeking out fashion that is ethical and sustainable while avoiding fashion that is unethical and unsustainable.

Unfortunately, much of the fashion industry today is dominated by fast fashion and ultra-fast fashion companies like Shein and H&M. These companies churn out new designs (often stolen from independent designers) on a constant basis, selling clothes made from cheap, synthetic fabrics for prices so low that it’s almost impossible to resist buying them.

It turns out, the fabrics that are most prevalent in fast fashion are also the least sustainable ones. Synthetic fabrics like polyester – derived from fossil fuels – are easy and cheap to produce in large quantities. And although conventional cotton is a natural fiber, it is also one of the cheapest fabrics available because of mass production, synthetic fertilizers, and unfairly paid labor. But the low prices of the fabrics used in fast fashion come at a huge cost to the environment, wildlife, human welfare, and your own health.

Collectively, these unsustainable fabrics are responsible for pollution to land and water of chemicals, toxins, and microplastics; significant greenhouse gas emissions; heavy water use leading to water insecurity near factories; unsafe and unethical working conditions; and more. And if that weren’t enough reason to avoid them, cheaply produced fabrics have been found to contain numerous toxic chemicals linked to adverse health effects.

By doing your best to avoid the “worst offenders” when it comes to fabrics, you are protecting yourself, workers, and the environment and helping decrease consumer demand for such products. It might not seem like much, but enough people acting collectively can impart change, and that’s what we need right now.

The 6 least sustainable fabrics

Without further ado, the fabrics that are worst for the environment and human health are polyester, conventional cotton, viscose, nylon, acrylic, and spandex. While there are certainly other fabrics that are considered unsustainable, these ones are by far the worst and should be avoided when possible.

Polyester

There is no doubt about it: polyester is the least sustainable fabric in the world today. Each year, 61 million tonnes of polyester are produced, representing a market share of a whopping 54%, more than all other fibers produced, combined.

But it’s not just the massive scale of production that makes the environmental impact of polyester so significant. Polyester is a synthetic fiber derived from non-renewable fossil fuels. In other words, it’s a type of plastic not dissimilar from what’s used to make plastic bottles and containers.

While polyester fabric is useful for its stretchiness and durability, it releases microfibers (a type of microplastic) every time that it is washed. The microfibers end up in the water supply, where they can’t be filtered out and eventually end up in rivers, streams, and oceans where they can be ingested by wildlife, leading to a cascading effect throughout the food chain. What’s worse, these microfibers never fully break down in the environment.

Additionally, the production of polyester consumes as much as 71,000 cubic meters per ton of fiber, more than the majority of conventional cotton – which is often considered one of the thirstiest fibers to produce. While some of the wastewater can theoretically be recycled, most polyester manufacturing plants do not have the systems in place to do so. Instead, the wastewater – often loaded with toxic chemicals – is discharged, often without proper treatment. The hazardous pollution can endanger wildlife, plants, and humans.

Conventional cotton

Cotton is one of the most confusing fabrics when it comes to sustainable fashion. Often, natural fibers are cited as being a more sustainable alternative to synthetic fibers. While this can be true, it is not the case for conventional cotton. On the other hand, rest assured that organic and recycled cotton are more sustainable alternatives.

Conventional cotton is particularly unsustainable because it is not only widely grown, but also incredibly thirsty. A single pound of cotton fiber requires 1,320 gallons of water to be grown and processed (and that’s not counting the amount of water it takes to create clothing from the fiber). By comparison, responsibly-grown flax (used to make linen) can be grown without irrigation at all.

Additionally, conventional cotton is grown with tons of synthetic fertilizers, pesticides, and herbicides. These may result in higher yields, but leave the soil barren after harvesting. Plus, synthetic pesticides in particular have been linked to increased cancer risk in workers and their spouses. And these chemicals don’t just disappear; they are washed away by rain and irrigation, ending up in the soil and water supply where they can endanger humans, wildlife, and plants.

Viscose

One fabric that is subjected to greenwashing more than any other is viscose. Viscose is a type of rayon fabric; an umbrella term for semi-synthetic fabrics derived from plant material. The terms viscose and rayon are often used interchangeably because viscose is the predominant type of rayon fabric. However, other rayon fabrics include modal and lyocell, the latter of which is considered a more sustainable fabric.

Most viscose fabric is derived from wood pulp from fast-growing trees like beech or eucalyptus. Increasingly, viscose is also being made from plants like bamboo or soy. Though technically derived from plant material, the pulp undergoes a chemically-intensive process that isolates cellulose before chemically regenerating it and spinning it into a usable fiber. At least, that’s the short of it. You can learn more about the viscose process here.

Though viscose and rayon fabrics are often referred to as more sustainable alternatives to polyester or cotton, it’s rarely the case. Most conventionally produced viscose is responsible for deforestation, heavy water use, and dangerous working conditions. For example, the chemicals used in the viscose process are typically highly toxic, which is not only dangerous to the workers but also dangerous to the surrounding communities, landscape, and wildlife when the chemicals are inevitably leaked into the water supply.

Is bamboo fabric sustainable?

Bamboo is increasingly touted as a highly sustainable resource. In theory, this is true: bamboo is not only the fastest growing plant on earth, but it regrows from its roots, so you don’t have to replant it after cutting it down. Plus, it can be grown without the use of synthetic fertilizers, pesticides, or herbicides.

However, just because it can be grown responsibly, doesn’t mean it always is. In China, the high demand for bamboo products has led to large monoculture bamboo farms that are resulting in deforestation and habitat loss. Plus, growers chasing higher and higher yields may rely heavily on chemical fertilizers and pesticides, at the cost of soil and water health, not to mention biodiversity.

Most fabrics that are advertised as “bamboo” are actually viscose. So even if the bamboo was grown responsibly, the viscose process is highly water-intensive and polluting, and cannot be considered sustainable. But all is not lost. There is one type of bamboo fabric, referred to as bamboo linen, that is made through a mechanical process rather than a chemical one. However, this process is expensive and labor intensive, so it’s difficult to find textiles made from this fabric.

In an attempt to curb the flood of misinformation around bamboo textiles, the Federal Trade Commission (FTC) outlines regulations for companies selling bamboo products. In particular, fabrics may be “derived from bamboo” but they may not be called bamboo unless they are directly produced from bamboo fiber.

Nylon

Nylon is another synthetic fiber that is commonly found in tights and active-wear. Like polyester, nylon is derived from crude oil and is therefore non-biodegradable. Similarly, nylon releases microfibers every time it is washed. While you can reduce microfiber pollution at home by washing less or using a microfiber filter, it is impossible to prevent it entirely.

The production of nylon itself is unsustainable not only because it relies on non-renewable fossil fuels, but because it is energy-intensive and water-thirsty. Moreover, nylon production releases nitrous oxide (N2O), a greenhouse gas that is 265 times more potent than carbon dioxide and which remains in the atmosphere for 121 years on average.

Acrylic

At this point, it should come as no surprise that any fabric derived from fossil fuels is considered unsustainable. Acrylic, commonly used in place of wool in sweaters and rugs, is made using highly toxic chemicals such as acrylonitrile. While many chemicals are washed off at different stages of the manufacturing process, some are known to remain in fabric. But this doesn’t necessarily mean you’ll get sick from wearing an acrylic sweater; more importantly, these toxic chemicals are extremely dangerous for the workers who are exposed to them on a much larger scale.

Moreover, like its cousins polyester, nylon, and viscose, acrylic is non-biodegradable and will remain in the landfill for hundreds of years. While you can recycle synthetic fabrics such as acrylic, it’s important to understand that they are more often than not downcycled into lower-grade materials like carpeting or insulation. Still, that’s better than taking up space in the landfill.

Spandex

Finally, spandex – known as elastane in Europe – is another stretchy synthetic fabric that is particularly useful for athletic wear, leggings, and swimsuits. However, it is also derived from non-renewable fossil fuels. Therefore, it makes the cut as one of the least sustainable fabrics on the market.

In particular, the spandex manufacturing process is energy-intensive and polluting. Many toxic chemicals are used throughout the process, some of which will remain in the fabric and may cause health concerns for the wearer.

And, like all other synthetic fabrics on this list, spandex contributes to microplastic pollution by shedding microfibers each time it is washed. At the end of its life, spandex can’t be easily recycled, so it often ends up in the landfill where it takes up valuable space and doesn’t biodegrade.

Did you know the true impact of these common fabrics? Will knowing this information help you avoid them in the future? Why or why not?