In my heart, as a conscious fashion consumer, I feel like I should prefer silk. It’s a natural, beautiful, traditional, and luxurious fabric. Obviously.

That’s why I’m cynical when fast-fashion brands like ASOS announce they are banning silk from their offerings. I don’t think they’re doing it for altruistic reasons, but rather that they want to save money by using synthetic and semi-synthetic alternatives like polyester and rayon/viscose. The praise they get from vegans on social media is just a nice little bonus.

But then, I kept hearing that silk actually has a high environmental impact.

According to the Higg Index, silk has by far the worst impact on the environment of any textile, including polyester, viscose/rayon, and lyocell. It’s worse than the much-demonized cotton, using more fresh water, causing more water pollution, and emitting more greenhouse gases.

Honestly, if this is true, then I feel like a chump. Why have I been paying so much for silk — fussy, stain-able, dry-cleaning-required silk? Should I just switch to alternatives?

Let’s break it down. For this fabric analysis, I’ll be comparing silk to the fabrics that could replace it: polyester, viscose/rayon, and Tencel, which is the branded name for lyocell from Lenzing. Unless otherwise stated, I’m getting my information from Textile Exchange and Higg.

Silk and Climate Change

Where silk causes the most environmental damage is in energy usage. Silk farms are kept at a certain humidity and temperature (65 degrees). Because most silk is made in hot climates in Asia, that requires a large amount of energy for air conditioning and humidity control. Silk farms also use steam or hot air to dry the cocoons after harvesting, which also requires a large amount of energy (just like when you use hot water to wash your clothes and then dry them). This could be provided by burning mulberry wood, but it’s most likely provided by whatever the municipal energy source is: a coal-fired plant.

Conclusion: If your first (and only) concern is the climate, you could justify a switch to polyester which according to Higg has the lowest climate impact of silk alternatives, but only by a little. You could also switch to lyocell/Tencel. Or, you could find and work directly with a silk farm that sources alternative forms of energy.

Does Sericulture Use Toxic Chemicals?

Where silk does better than alternatives is in its tiny land and chemical usage. The silkworms munch on the leaves of mulberry trees, which are mostly grown without the use of pesticides — since pesticides can harm silkworms — on marginal land that couldn’t be used for other crops.

Some silk producers are better than others. To protect silkworms from disease, some silk farms treat their enclosures with disinfectants such as formaldehyde, lime, or chlorine. But sun drying, steaming or hot-air sterilization are available as chemical-free options. Sometimes hormones are given to pump up the worms’ growth and silk production. Silk could also be “weighted,” or made heavier and more lustrous by applying metallic salts, which could increase the toxicity of the silk as well as the wastewater. But the main potential place for toxic chemicals is when silk dyed and finished. That is the same as most other fabrics.

Conclusion: If this is important to you, ask for silk that hasn’t been weighted, has been colored with low-impact dyes, or is certified organic: produced without any synthetic chemicals or growth hormones.

Silk as a Zero-Waste Fabric

All of silk’s byproducts are integrated back into the local ecosystem and economic system. The mulberry fruits are eaten, the wood is used for timber or fuel, the foliage is fed to cattle, extra waste is used as fertilizer, and lower quality silk is used as filling in silk products like duvets. Sericin, which is recovered from the wastewater, can be added to food, cosmetics, textiles, and pharmaceuticals.

As a natural fabric, silk also biodegrades if you bury it or it ends up in the ocean or a waterway. As I’ve reported before, the other silk alternatives: viscose/rayon, lyocell, modal and Tencel, all biodegrade as well. Polyester? Well, you know the deal.

Conclusion: Silk is a circular and zero-waste fabric. If this is important to you, avoid polyester alternatives, but Tencel would be OK.

Does Silk Production Use a lot of Water?

The organization Textile Exchange disagrees with Higg’s assertion that silk production requires a lot of fresh water. According to TE’s fact sheet, although a silk farm will use up to 1,000 metric tons of water to produce one metric ton of silk, mostly to soften the cocoons for reeling the silk — this is less than cellulosic fibers like viscose, rayon, lyocell, modal, Tencel, etc. Why the discrepancy? The Textile Exchange’s source is a rather old fact sheet from the Food and Agriculture Organization of the United Nations, which is suspect. Higg bases its calculations on data on the best available LCAs, some of which are public, and some private from brands.

Some have suggested that Higg’s data is influenced by fashion brands, so I contacted Jason Kibbey, CEO of Higg, to ask him. “No. There’s a third-party gatekeeper, and this is best practice for LCA methodologies to keep them free of influence. Tom Gloria at Harvard is our gatekeeper, he’s a well-known LCA expert who reviewed the data for soundness before it entered the MSI. He has the ability to reject data and has criteria he uses to evaluate the data. If you’re an SAC [Sustainable Apparel Coalition, a voluntary industry group which spun off Higg last year] member who has what you think is really awesome viscose, but your LCA is low quality, you’re not going to get any benefit when it goes through the gatekeeper of the process, which is arm’s length and separate from the SAC. If there are two LCAs he’ll review both of them for quality and completeness, and if one of them is public and one is private, he’ll pick the highest quality LCA and has public information and put it in the Higg MSI.” He went on to say specifically about silk, “If there is a better LCA out there that shows different results, the Higg MSI process is happy to review that and update its model. In the past, we have updated the data in the MSI for other fibers.”

So, it sounds like Higg is using the best LCA data on silk available. But if you have better data, do let them know!

Conclusion: Silk is (probably) a way thirstier fabric than Tencel, rayon/viscose, or polyester.

Is Silk Ethical?

To make silk, larvae are killed by steaming before they eat through the silk cocoon. If you’re the kind of person who eats humanely-raised meat, then this aspect of silk shouldn’t bother you at all. Researchers haven’t found evidence that silkworms experience pain, or suffer when they’re killed inside the cocoon, and in China and Vietnam, they’re sold at the market as a tasty protein source.

There are non-violent silk alternatives, known as Ahimsa or peace silk, where the moths are allowed to emerge. But since they’ve been bred for centuries for the purpose of creating silk, they live only a couple of days, bumbling about with their tiny, completely inadequate wings. It seems hardly worth it compared to lessening the suffering of a sentient cow or pig. And the resulting peace or Ahimsa silk is more expensive and less refined than typical silk. Is it worth it to pay more so that the moths can live a few extra days? PETA certainly doesn’t think so, since the process still uses animals.

As for labor? On that count, Quartz reports that silk can be good or bad. China is the world leader in silk production followed by India, Uzbekistan, Brazil, Iran, and Thailand. Like many other products ranging from chocolate to embroidery, silk has been connected to child labor in India and Uzbekistan. But it is also one of the few remaining ways to earn a solid income in rural areas in Asia, especially for women. In Madagascar, harvesting wild silk is helping to protect the rainforest.

As a traditional fabric with a rich history, it would be a real loss to see this traditional fabric be supplanted by factory fabrics. Then again, most silk comes from large industrial operations in China, which are hardly traditional or rural. It’s not common for brands to know where their silk is made, unfortunately.

Conclusion: Like most ethical issues in fashion, this one isn’t really quantifiable. Whether you consider silk ethical depends on your priorities: preserving tradition and supporting rural artisans, or wearing only animal-free products. We could definitely use more transparency around how and where silks are made, but that’s no different than every other fabric, including industrialized ones like polyester and rayon/viscose.

Should You Ditch Silk?

The debate around silk and the environment reminds me of the debate over plastic bags versus reusable cotton bags. One just feels better. And yes, there’s no question that when it comes to waste, the reusable cotton bag and a silk top are both less likely to choke marine life than their disposable synthetic alternatives. This severe damage is just not measured lifecycle analyses, yet.

But when you compare the water and climate impacts of the two, plastic bags come out on top in a huge way. You would have to re-use a cotton tote thousands of times to bring its climate and water impact down to that of a plastic bag. The difference isn’t as drastic with silk versus polyester and viscose/rayon. You would have to wear a silk piece 12 times more than the Tencel version, 11 times more than the viscose/rayon version, and 15 times more than the polyester version to bring its environmental impacts in line.

I should also point out that LCAs are weighted averages of the industry. If, as a brand, you’re working directly with a more sustainable silk manufacturer, then great! Make sure to ask the manufacturer for its data on water and energy usage before you go crowing about it, however. If you’re buying silk at a textile retailer and can’t trace it back to the farm, you can probably rely on Higg for an accurate assessment of its environmental impact.

So I would say this to consumers: If you’re vegan, choose Tencel. If you’re not, go for the certified organic and non-toxic silk piece if it’s available, sure. But more importantly, only buy a silk or silk-like piece if it’s the kind of fashion that you will wear for years and years to come. Or, think ahead to when you’re done with it. Is it the kind of timeless piece that will be valuable to someone else in your community if you grow out of it? (Also, wash your silk by hand instead of taking it to the dry cleaner.)

In that regard, silk does tend to come out on top compared to polyester and rayon/viscose. It’s just more luxe, and less likely to end up floating as trash off Ghana’s shore. But with Lenzing coming out with a new luxury version of Tencel (see: sustainable dresses worn to the Oscars this year), well, maybe eco-conscious fashionistas will soon all be swathed in Tencel.

If that’s you, just spare a thought for the traditional sericulture farms of Asia, who will go out of business and take away another of the few remaining planks supporting a traditional, rural way of life. Maybe those people thrown out of work will find a job in a clean, bright, safe Tencel factory. Likely not.

Sustainable Silk Clothes

There are many sustainable fashion brands out there who take a creative approach to sourcing sustainable silk for their collections. Here are some of our favorites:

TRADITIONAL CRAFT

Kelly Wang Shanahan, the Founder and Creative Director of Ziran, started the line in 2016 after becoming disillusioned with the luxury fashion industry and its waste, fast fashion mentality, and lack of purpose. She discovered xiang yun sha silk while researching ancient Chinese techniques and instantly fell in love with both its luxurious beauty and cultural significance. Xiang yun sha silk not only preserves cultural heritage, but it is completely natural, wrinkle-resistant, anti-microbial, and skin nourishing. Everything is cut and sewn ethically in Los Angeles.

Each Roopa piece is designed as a future heirloom, to be thoughtfully handed down from one generation to the next, reinterpreted over and over again. All manufacturing processes take place under one roof in Bangalore, India where skilled artisans collaborate on each collection and ensure the skills and craftsmanship like beading, embroidery, weaving, dyeing, and printing continue to grow, flourish and evolve. Everything is colored using natural, eco-friendly dyes.

Arielle combines naturally grown (pesticide-free) hemp with tussah, or wild silk. The vast majority of the silkworms are allowed to work their way free of the cocoon and continue their lives; the few that don’t end up as highly-prized delicacies for the fiber workers. The Arielle team sources all materials with great care and responsibility, enforcing supply-chain transparency, human rights standards, and environmental protection. Everything is sewn in NYC.

AGAATI’s luxury designs are inspired by nature. Everything is made by skilled artisans—many of them women—out of natural, non-toxic materials and with a zero-waste philosophy. The brand also gives back 5% of profits to NGOs which support women empowerment and create employment for artisans around the world.

This brand’s name (apéro) comes from the French evening ritual that combines drinks, food, and friends at a bistro terrace or at home. La Femme Apéro creates beautifully elegant yet simple pieces exclusively made of silk and silk/cotton blends. Designed and produced in small quantities in NYC, these pieces would be perfect for a special occasion or a statement piece in your capsule wardrobe.

Based in NYC and Cape Town, The Folklore is a curation of pieces made by emerging ethical fashion designers in Africa. Almost everything is handmade and either one of a kind or only available in small batches.

Iro Iro is a sustainable design practice where each product is made using pre-consumer waste fabric which is handwoven by a traditional family weaving unit outside of Jaipur into new fabrics. This upcycled textile is then used to create clothing and accessories using zero-waste cutting techniques.

WASHABLE SILK

Sourcery’s washable silk uses the highest quality, 100% naturally grown silk from a region of China that has been producing silk for thousands of years. All of their fabrics are OEKO-TEX Standard 100 certified and all of the dyes used are non-toxic. Sourcery spent months coming up with a silk that can be washed, which is amazing since most conventional dry cleaning is terrible for the environment.

NON-TOXIC AND PLANT DYES

Flora Obscura pieces are made out of silk charmeuse, which is great for year-round wear since it’s both insulating and breathable. The silk is first imbued with flowers through a steaming process, then dyed or hand-painted with natural dyes. Once it’s reached the desired color palate, the silk is then cut and sewn into a garment. Each piece is made from start to finish by the same pair of hands, a one-of-a-kind work of art.

97% of everything Amour Vert sells is made right in California by a family-owned operation. Their non-toxic dyed silk is OEKO-TEX® certified and the scrunchies above are made from fabric scraps!

Natalija’s pieces are all made in Sydney, Australia with a manufacturer accredited with Ethical Clothing Australia. Their silk is derived from sustainable cultivation processes and the mill they work with upholds ancient traditions established centuries ago and goes to great efforts to maintain the same exacting standards and sourcing their mulberry leaves from the very same fields.

SECONDHAND

TheRealReal is an authenticated online consignment shop that carries the biggest luxury brands out there. Their 100+ in-house expert team includes gemologists, horologists, and luxury brand authenticators who inspect thousands of items every day, ensuring everything they sell is 100% authenticity guaranteed. They also teamed up with the Ellen McArthur Foundation, Stella McCartney, and the World Resources Institute to create a circularity calculator to keep track of how much water and CO2 have been saved through their job, just by consumers shopping secondhand. (Just take its accuracy with a hefty grain of salt.)

You will find more vintage luxury pieces on Vestaire Collection, which is more heavily curated based on brand. You can shop designer silk pieces for both men and women.