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Are Natural Dyes Better For The Environment?

Updated: Nov 22, 2023

Are natural dyes a thing of the past? The world has moved on to using synthetic dyes and petrochemicals that are less expensive, time-consuming, and produce consistent, repeatable results.


However, as the world becomes more environmentally conscious, people are looking for ways to reduce their dependency on petrochemicals and the often toxic byproducts of petrochemical-based dyes.


Today some seek to reintroduce traditional dyestuffs back into commercial dyeing. These dyes are sourced from natural substances, such as plants and insects, to be used in a variety of industrial uses, from textiles to foods.


Let's examine the history and late 20th-century resurrection of natural dyes in the commercial environment.


An oh, so brief history of natural dyes


Evidence of natural dyeing exists in many ancient cultures worldwide. Dye and pigments were found in textile fragments as early as the 3rd millennium BCE. Textile fragments dyed from madder roots (Rubia tinctoria) in Pakistan and Egypt, dating around 2500 BC.


The Pazyryk

Oldest Rug

The Park carpet is the world's oldest existing rug at some 2,500 years old.


Unearthed by Archaeological digs in central Asia's Pazyryk Valley in the 1920s unearthed a wealth of historical items from a little-known ancient nomadic tribe of the Pazyryk. Including the world's oldest surviving carpet, the mostly intact Pazaryk rug from the 5th century BCE.


While much is not known or conjectured about the Pazryk rug, by the 3rd century BCE, rug weaving and dying were considered well-established art forms by many.


Perhaps the most intriguing aspect of the Pazryk Rug is the use of Polish Cochenial (Porphyrophora Polonica), a dye from Northern Europe, in a rug made in what is modern-day Iran or, as some suggest, Armenia.


The use of natural dyes in pre-recorded history isn't limited to Europe, the middle east, or central Asia. We know by 1,000 BC, elaborate dyed textiles were being made with natural dyes in the Americas; many examples survive due to the preservative effects of the dry coastal area of Puru. So far, it's impossible to tell how long humans have used dyes for textiles, and like the existence of human activity in the Americas, an incomplete picture exists.


Silhuas Vally, Puru weaving 500 BC


Where do natural dyes come from?

Natural dyes are derived from plants such as madder or insects such as cochineal and Kermies. A surprising number of plants have dye properties, and the most common natural plant colors are yellows, browns, pale tones, olive green tones, and a large variety of plants containing dye compounds. This is due to common chemical compounds found in plants called flavones.


Much rarer are plants that yield deep reds, blues, and purple color tones.


A series of steps or processes must be performed to dye with the most natural dyes, or the dye will not take. In most cases, one cannot get a good deep, stable color with natural dyes that is reasonably colorfast without applying a mordant or metallic salt as a mordant.



Commercial madder dye vat in Iran
Madder dye vat Iran

Madder-dyed wool, for example, must be mordanted before dyeing. For a true red Alum, sodium aluminum salt is used in the 3-5% by weight of wool range.


Mordanting is a process where the wool is soaked in a metal salt, and the salt acts as a bridge between the dye and fiber, bonding together in a chromophore. So twice as much water is needed to dye with many natural dyes than synthetic dyes. The use of water is a substantial issue in commercial textile production, both in use and effluents in wastewater and natural dyes are no exception.


Failure to properly mordant the wool often results in poor color or dyes that wash out.



In contrast, a synthetic dye is engendered with the dye and mordant together as one compound, and the dyeing process happens in one step.


However, in some places, dyers are unfamiliar with the working properties of these dyes' pH ranges and temperatures of synthetic dyes are critical in dyeing.

Wool being dyed
Dye Vat in Kabul

In this photo of a dye house in Kabul, an excessive amount of synthetic blue drips from wool. Most likely from improper pH adjustment of the dye vat during dyeing.


While on paper synthetic dyes are more efficient that doesn't always translate in the real world. In Afghanistan language barriers, education, and access to simple things like pH testers.


In some cases, synthetic dyes not intended for wool a used, and the dye initially looks good but fades or bleeds when washed. Common in Morrocan rugs leather Analine dyes sometimes find their way into wool carpets




Indigo Dye

Indigo is a natural dye from the indigo plant that has been synthetically synthesized at the turn of the 20th century. Traditional Indigo is fermentation in this process; the oxygen is reduced from the dye vat by fermentation. Indigo is not water-soluble, so to be dissolved, Indigo must undergo a chemical or fermentation reduction of oxygen atoms that converts Indigo into "white indigo" or leuco-indigo, allowing the Indigo to penetrate fibers. When Indigo is exposed to air, it oxidizes and forms larger and very stable chemical compounds.


The Rise of Synthetic Dyes

In 1856, chemist William Perkins invented the first synthetic dye; before that; all dyes were derived from plants, animals, or minerals. William's invention of mauvine (purple) and subsequent aniline dyes from coal tar changed the dyes, design, and dyeing for future generations.


The grey in this Germantown Navajo is Mauvine Purple now faded from time and sunlight and the red bleed into the white.

Synthetic dye fade in a Navajo rug
Germantown Navajo

From the 1860s on, most of the world eagerly adopted these new dyes. While many had issues fading in sunlight and colors bleeding during cleaning, these dyes were relatively easy to use and increasingly cheap. Ultimately synthetic dyes became much more affordable and less labor-intensive than natural dyes.


In 1865 the German chemist Adolf von Baeyer began working on the synthesis of Indigo. It wasn't until 1897 that Bayer and BASF developed a commercially feasible manufacturing process for synthetic Indigo. In the same year, 1897 19,000 tons of natural Indigo were being produced mainly in India from plant sources; by 1914, natural indigo production dropped to 1,000 tons.


Synthetic Indigo dye production
BASF synthetic Indigo circa production 1890

Synthetic dye use exploded in the early 20th century, yet; there were some holdouts. In Persia (Iran), laws were enacted banning the use of synthetic dyes in oriental rugs, although the use of synthetic dyes did find its way into some Persian rugs.



Dye purity laws existed in Iran /Persia until the the1940s when they rescinded the law, ushering in the wholesale use of synthetic dyes in the Iranian rug market.


In less than a hundred years, a dye industry with ancient roots, methods, and processes that had existed for thousands of years was gone. In many weaving cultures like Iran, a dyer was skilled apprenticeship trade passed down often in families or guilds. A dyer's recipes and techniques often guarded trade secrets passed from generation to generation, perhaps over hundreds if not thousands of years. These skills were learned trade not written in textbooks or large manuals; many simply ...disappeared. The proverbial carpet was pulled out from under the natural dyer's feet.


Post world war two, economic and technical innovations solidified the use of synthetic dyes and for that matter, synthetic fibers. Rug weaving was on the decline not just in color but qualitatively weave and materials. The cheaper quick dyes led to cheaper weaving and reduced quality of materials. As well as the emerging competitive market for wall-to-wall broadloom carpets.


An aggregate effect of cheaper alternatives leads to cheaper synthetic dyes, cheaper wool, and lower knot count for a cheaper rug to compete with much lower price points. ?


By 1970 an interest in antique rugs made with natural dyes was growing in Europe and America. Driven by post ww2 baby boomers and the counterculture movement kindled interest in good Antique rugs with natural dyes.


Natural Dye Renaissance


In 1981 DOBAG project was founded; DOBAG Turkish acronym for "Doğal Boya Araştırma ve Geliştirme Projesi" (the Natural Dye Research and Development Project). The program's goal was to make rugs with dyes and dye processes not used in nearly a hundred years.


The program was a success, and companies followed, such as Woven Legends making new rugs with natural dyes. This natural dye movement flourished in the 1990s in what we called the "Renaissance in Rug weaving" these rugs were much more expensive to make, and much of the rug market was not interested in paying the price.


If you have ever wondered why we call our business Renaissance Rug Cleaning it's because we believed the "Renaissance in Rug Weaving" should be met with a "Renaissance in Rug Cleaning"

Are natural dyes more environmentally friendly?

There are many factors to consider; natural dyes are more farm intensive and require water, fertilizers, and energy to harvest and process. In my research, I could find no energy comparison between natural and synthetic dyes.


As described above most natural dyes are more water-consuming and intensive than synthetic dyes. Wool, for example, must be mordanted in a separate process before dyeing, requiring double the water to achieve color.


Compared to modern synthetic dyes, that exhaust efficiently and a single dye vat can be used for multiple dye sessions, often starting with the lightest color and working to the darkest one. There is no question that well-trained dyers with synthetic dyes are more efficient, use less water, and produce less waste effluent into the environment. Today, synthetic dyes are stable for washing and offer good resistance to sunlight adding when properly used.


Yet Indigo can be done in one dye pot process and naturally via fermentation reduction, so it's not more water-intensive or chemically consuming its wastewater is biodegradable and not toxic.


Enter clothing giant Patagonia

In 2014, Patagonia was the first major clothing company to remove synthetic Indigo and replace it with natural Indigo for all their jeans. Patagonia approached Stony Creek Colors, a grower of natural botanical Indigo Tennesee, to provide Patagonia with all its Indigo needs.


In 2021 Stony Creek Colors raised 9 million dollars to expand its natural Indigo production in the USA, signaling that botanical Indigo is back, growing, and seemingly not just a short-term fad. In 2019, More Indigo was traded and worked worldwide than at any time since 1920.


It's not just Patagonia, Wool and Prince, Ice Breaker, and other clothing manufacturers are exploring natural dyes for commercial textiles clothing production as a greener alternative to petrochemical-based dyes and colors. It's unclear how big of a place natural dyes will play in the future in the commercial rug and textile production, although it's likely to be a hybrid.



It's inaccurate to say as a blanket statement that natural dyes are more environmentally friendly than synthetic dyes. In rug production, a hybridization of dyestuffs is natural and synthetic for effect. As we try to ween ourselves off petrochemicals, the future may be a new type of dye compound. Natural dyes enhanced with chemically engineered mordants or hybridized natural dyes blend the performance of chemical and natural dyes.





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