The subject dyes is little discussed when considering sustainability and ecological footprint of a garment. We are more inclined to take into account the organic culture of the fibers, the transformation processes of these fibers or the conditions of the workers when it comes time to make a purchase. As a result, there aren’t many companies who are interested in putting the effort necessary to detail the dyes used on their clothing. It doesn’t seem to be one of the most interesting subject for the public, and yet it should be.

There is no legal requirement to write the dyeing processes on the garment label, as it’s the case for fiber composition and country of manufacture1. But this step is crucial. It is increasingly pointed out as a great source of pollution not only when the garment is dyed at the factory, but also when it is washed in our domestic washing machines then poured out into our water treatment plants or septic tanks not well enough equipped2 to handle these products.

The complexity of the subject is certainly the main obstacle to the understanding of the problem and  the awareness of the public. There are many different dyeing processes 3 (reactive, acidic, dispersed, vat, …). In addition, some products may or may not be used in dyeing: mordants (to help with the quality and durability of coloring, colour fastness), wetting and dispersing agents (to help disperse and improve speed of the process). All this to finally give a cocktail that can be difficult to explain.

A bit of history

Like many aspects of the textile industry, synthetic dyes are a relatively new phenomenon. They were invented by mistake in the middle of the 19th century when a chemist created a purple dye from coal tar4. Synthetic dyes took over the market almost instantly in the late 19th century5. They were cheaper and more efficient than their alternative dyes made from plants or natural products.

What is a synthetic dye?

It is important to understand that a textile dye is a synthetic element derived from petroleum products. Although ideologically, it is not ideal to use products that come from the petrochemical industry, this does not seem to be the biggest problem related to dyes. Other products used in the dyeing process (mordant or wetting agent) are toxic products and should be the products to worry about. Paradoxically, toxic mordants can be used for natural dyes.

The problem


The most visually striking and often the most reported problem is the discharge of untreated (or even treated) wastewater from dyeing plants. It’s released directly into the environment and contaminates drinking water sources that humans and animals depend on. In most developed countries, laws are in place to regulate the treatment of factory water and the products used. On the other hand, this is not the case for most developing countries, which are now the largest clothing manufacturers.

In Canada, ecologists have worked with our elected officials to put in place the Canadian Environmental Protection Act6, voted almost 20 years ago in 1999. A well-identified subject in this legislation was the Effluents from textile factories2. In other words: water that is rejected from textile dyeing plants.

In short, several studies have been conducted to conclude that water discharged by textile mills was toxic even if these waters were either treated in the plant and / or discharged into a water treatment system. There were still toxic residues after the treatment.
So we voted to force the textile mills to take tests, treat their wastewater and comply to not using a list of products7 considered toxic. Included on this list are Nonylphenol and its ethoxylates (Wetting agent better known as NPEs), Benzidine and benzidine dihydrochloride (known carcinogen), Formaldeyde, Benzene, Toluene diisocyanates, bis (2-ethylhexyl) phthalate ). Mordants that contain heavy metals: Mercury, lead, chromium compounds, Inorganic cadmium compounds, Oxygenated, sulphidic and soluble inorganic nickel compounds.

Admittedly, it was a good job of our legislative system. Since the early 2000s, textile dyeing plants have been closely monitored and we have less to fear from water discharges in Canada. Annual reports on CEPA8 are available online. On the other hand, the implementation of this law coincided with the massive export of clothing manufacturers to developing countries and China. Of the 145 textile dyeing plants operating in Canada in 19992 (58% of which were in Quebec), a handful9 remain.



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The problem persists because the majority of clothing sold in Canada is made (and dyed) in countries that do not have regulations like ours. So, not only do these textile dyeing plants release toxic water (which is now far from us, but that does not mean we shouldn’t worry about it), but we are still directly affected by these toxic products who are transported on the garments we buy. When those are washed in our domestic machines, either dye particles that have not completely reacted or mordant (heavy metals) or NPEs are released in our septic tanks and in our water treatment plants.

And that has not changed, our water treatment plants are still not able to completely eliminate NPEs. And even if it did, the mud waste from these factories is buried later.

As long as there are no rules for identifying dyeing processes on clothing composition labels. It will be impossible to prevent the importation of garments carrying toxic residues.


It goes without saying that if the residues of the products are on the clothes, they are necessarily absorbed by the skin and go directly into our body. The products are no longer on the garment after a few washes (they have been transferred to our water treatment systems). But who wants to take this risk. Yet, we do it because we just don’t have the information. Well the information is there but few take the time to dig for it.

Eco-Friendly Dyes

When talking about eco-friendly dyeing, there is no quick fix. Even dyes based on natural dyes can be used with mordants that contain heavy metals10. Today, industrial suppliers that offer natural dyes no longer exist. One can dye some pieces of clothing with natural dyes personally, but to dye 500 meters of fabric rolls, there is no dyer who offers a natural alternative nowadays. At the industrial level, the best one can do is to used low environmental impact reactive dyes and focus on avoiding the heavy metals mordant and NPEs. But still synthetic dyes.

In our research we found only one company, in Canada, that offers handmade scarves that use with a natural dye: Infuse

And I know of only one company who use natural clay based dyes on a fair proportion their clothing. It’s Earth Creation based in Bessemer, Alabama, USA.

Maybe it will be something that will be developed by Respecterre in the future.


It is good to highlight the problem, but what can we do to act now for our health for all and for our environment? Here are 3 tips to buy your clothes with the certainty that they do not contain toxic products.


As discussed above, with the Canadian Environmental Protection Act, 1999 (S.C. 1999, c.33)6, we can be confident that a garment dyed in Canada contains no toxic residue. Many countries in Europe, the United States and other developped countries have similar regulations.

It not easy to know if this is the case, as it is not a requirement of the Competition Bureau1 to have information on dyeing on the label of the garment. Take the time to ask the clothing brand. If these company see that there is a customer interest in this, they will be more interested in displaying this kind of information.

Something that is knitted in Canada has more chance of being dyed in Canada.  Most of the time the dyeing process happens once the fabric is fully knitted or woven. Avoid products made abroad. They are necessarily dyed abroad. Caution, “Made in Canada” does not necessarily mean “Dyed in Canada”.


The OEKO-TEX® STANDARD 10011 is an independent system created in Switzerland in 1992 to detect harmful substances in textile products. Several laboratories around the world are part of this association can test the products to certify them without danger to health. The list of harmful substances12 in this system is very comprehensive. It tests: mordants of heavy metals (Arsenic, Lead, Cadmium, Chromium, Cobalt, Copper, Nickel, Mercury), Phthalates, Benzenes and Chlorinated Tuolenes, Perfluorinated Compounds (PFCs), Nonylphenol (NPEs) and several other harmful products.

So either a finished garment is certified OEKO-TEX® STANDARD 100  (there will be a label in the garment if it is, next to the composition label). Or, a fabric (or any other trim, button, zipper, etc) can be certified OEKO-TEX® STANDARD 100. Currently, not many clothing are certified by the OEKO-TEX® STANDARD 100. Encourage your favorite brands to have their clothes tested for certification that they do not contain any toxic products!



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Colours named “natural” are most often the original colour of the fiber and have not been dyed.  It will look like an off white or light brown depending on the type of fiber. By getting this colour, it’s certain that there won’t be any toxic substance related to dyes. Simple but not universal.


As with many environmental problems related to clothing, buying second-hand clothes is one of the best ecological and economical solutions. It’s also the case to avoid harmful products. These, who were on the garment when new, were removed as it was washed during its first life. In addition we reduce the volume of clothing destined for the dump. And all that for an unbeatable price.


In closing what has certainly been the article that has required the most research on this blog, it is obvious that the subject of dyeing is complex and that the vast majority of consumers do not understand the full extent of the it. There is no simple and universal solution, but one way to make sure that the products you buy do not contain toxic products is to ask the company where the clothes are dyed and if it has been tested with the OEKO-TEX® STANDARD 100 or buy a natural no dye colour. Never forget that if the consumer is interested in these topics, apparel companies will certainly become interested too.

Other technologies exist for the future. Like this machine that allows to dye without using water or toxic products… It only dyes polyester for the moment. If you’ve read our article “Plastic Clothing Causes Microplastic Pollution”, you know what our opinion on polyester is. But, do not believe that the consumption of polyester will not go from 30 million tons to 0 overnight. Can this kind of technology help minimize the damage?


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About the author Ugo Dutil: I grew up at the ecovillage “La Cite Ecologique” from 1 to 11. I decided to go back and live there when I was 25 years old. I like this way of life that allows us to prioritize human relationships over material possessions. I’ve been working with Respecterre since 2013. Minimalism and responsible consumption, especially in textiles, fascinates me.

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 Sources :
1. Canada’s Guide to the Textile Labelling and Advertising Regulation
2. Canadian Environmental Protection Act, 1999 – Effluents des usines de textile (FRENCH)
3. Different dyeing processes
4. A History Of The International Dyestuff Industry
5. The Birth of (Synthetic) Dyeing
6. Canadian Environmental Protection Act, 1999 (L.C. 1999, ch. 33)
7. List of toxic substances managed under CEPA
8. Archived annual reports CEPA
9. Active dyers in 2009
10. Toxic mordant can be used with natural dyes
12. List of harmful substances Standard 100 Oeko-tex
14. Greenpeace Dirty Laundry 12 pages
15. Wikipedia Nonylphenol
16. Greenpeace Fashion at the Crossroad
17. Greenpeace A Little Story about a Fashionable Lie 
18. We Have No Idea How Bad Fashion Actually Is for the Environment
19. NPEs (nonylphenol ethoxylates)
20. Nonylphenol (NP) and Nonylphenol Ethoxylates (NPEs) Action Plan 
21. Risk Management Approach for Acetamide, Disperse Yellow 3
22. Disperse Yellow 3 
23. Why natural dyes?
24. Health & Environmental Hazards of Synthetic Dyes
25. Ajax Textile Dyer
26. Wikipedia Oeko-Tex Standard 100
27. Detox Outdoor (PFCs)
28. Detox Campaigns