What fabrics are sustainable and non-toxic?
Fabrics are one of three types: (1) synthetic, (2) semi-synthetic, or (3) natural. You may know that synthetics are usually fossil-fuel-based and release microplastics, so it is best avoid those when possible.
So, what do you wear instead? Let’s break down synthetics, semi-synthetics and natural fibers.
What are synthetic fabrics?
Over 60% of the clothing produced worldwide comes from fossil fuel-derived resources including petroleum-based chemicals and petrochemicals (think: synthetic fibers like polyester, nylon, acrylic, spandex, elastane, lycra, chiffon, satin, “vegan” leather). From loungewear to professional attire, from underwear to bathing suits — synthetics make up the majority of wardrobes.
Petrochemical-based fibers are plastic, and can thereby release microplastics upon wear and wash. Microplastics have been linked to inflammation in the body, as well as providing an avenue for toxic chemicals to latch on and get into the environment and your body. In fact, studies have pointed to polyester and man-made fiber as accounting for more than 90% of airborne microplastics.
Polyester has even been used as a form of male contraceptive. Further studies are needed, but I would err away from wearing polyester, especially in underwear.
In addition, recycling plastic (especially water bottles) into clothing has become a trend, which is problematic in a few ways:
This is a highly toxic process, as plastic is cross-contaminated with chemicals when recycled. In addition, toxic chemicals are needed to turn plastic into fabric.
Once plastic water bottles are recycled into clothing, and the clothing reaches end of life, it is discarded. Whereas, the original plastic water bottle used to make the clothing could have been recycled back into more water bottles, creating a circular chain of recycling materials. The use of rPET into clothing thereby breaks this circularity chain (meaning, it stops the overall recycling process).
What are semi-synthetics?
Semi-synthetic fibers are sourced from the cellulose of plants (such as wood pulp), broken down, and reconstructed into a fiber. This happens in a factory and is usually a chemically intensive process, which is why these are marketed as half natural/half man-made.
The good thing is that as they are plant-based, in their pure form they are biodegradable. The bad thing is that depending on how they are made, the chemicals used in the process may be highly toxic, and depending on how they are blended with other fibers (such as synthetic) and dyed/finished, biodegradability is inhibited.
Common types and their health and environmental implications
The most common semi-synthetic fabrics are:
Rayon (also known as viscose)
Rayon is sourced from bamboo and trees and has a smooth feel to it. These plant sources are tough to break down and thereby need a heavy amount of toxic chemicals to turn them into a soft enough yarn for fabric. The production uses caustic soda to dissolve and purify the cellulose; this step uses the neurotoxin carbon disulfide which can then be introduced into the environment through the air or contaminated water.
The toxicity is mainly in this manufacturing process, possibly harming clothing makers who are handling these chemicals. In addition, excess chemicals from this manufacturing may be running off into nearby waterways, poisoning the water and impacting local communities.
Modal
Modal is made from beechwood and is processed to be a stronger variant of viscose. It is many times used as a cotton alternative in activewear, underwear, pj’s, bathrobes, sheets, and more. However, it has been linked to deforestation and harmful chemical usage depending on the manufacturer. Like viscose, its production uses caustic soda to dissolve and purify the cellulose. However, it uses less chemicals than viscose, making it a lower impact fiber.
Look for TENCEL Modal when possible, as Lenzing uses less toxic technologies in a closed-loop system (meaning chemicals are not released into the water upon use) and they harvest modal from sustainably harvested forests that are certified by the Programme for the Endorsement of Forest Certification (PEFC) or the Forest Stewardship Council (FSC).
TENCEL Lyocell
TENCEL is a trademarked form of lyocell by Lenzing. It has more of a silky feel and is made from eucalyptus. The processes to develop TENCEL are more sustainable and less toxic than the other semi-synthetics as they use an organic solution and closed-loop system. This is the semi-synthetic fiber I and GoodOnYou recommend!
What are natural fibers?
Natural fibers are those that are plant, animal, or mineral-based.
Types of natural fibers, their health and environmental implications
Natural fibers are preferred for both toxicity and sustainability. As a general note, they need fewer chemicals for production than synthetic (key word: “need”, although this is before we discuss finishes and dyes), are durable, and softer on the skin.
The most common natural fibers are:
Plants
Cotton
Naturally derived from the cotton plant, cotton is a staple fiber across clothing types. It is a breathable fiber making it optimum for workout wear and underwear. The main downside is the use of pesticides in farming. As such, look for organic cotton whenever possible to avoid pesticide use, along with regeneratively farmed cotton as that aims to decrease water usage and heal the soil.
Linen
Naturally derived from the flax plant, linen is a superior fiber due to its thermoregulating properties, strength and breathability (which is why it is a staple for summer weather!). Linen naturally needs less water and pesticide usage than cotton, but you can also look for organic options.
Hemp
Naturally derived from the stalks of the Cannabis sativa plant, hemp has a canvas look and feel, is not susceptible to shrinkage, is breathable, and is more durable than cotton. Hemp is also considered to be a carbon negative raw material, meaning that it absorbs more carbon than it produces. It requires very few pesticides, and does not require any herbicides.
Animal
Wool
Wool is a textile from the hair of sheep, goats, alpacas, llamas, and other animals. Wool is thermoregulating and naturally water-resistant, making it great for outerwear and cold-weather wear. It is decomposable and when it decomposes, it slowly releases valuable nutrients and carbon back into the soil. It is a wonderful option for a circular fiber.
The main concern with wool is its impact on animals. Sheep and other animals whose hair is a wool source naturally need shearing to deal with their environment. The problem, however, lies in the measures taken to shear the wool. Look for mulesing-free wool, meaning the breeder commits to not mulesing the animals and thereby does not harm them in the shearing process.
Merino wool is a great option for a sustainable fiber. Other wool fabrics include cashmere, angora, and mohair.
Leather
Leather has mixed reviews in the world of sustainability. Some leather manufacturing has been linked to deforestation. Leather also can impact greenhouse gas emissions. See more on the sustainability implications of leather here.
In regards to toxicity, conventional leather production uses chromium in the tanning process, often with formaldehyde and arsenic, which may find their way into waste water from factories. These chemicals are detrimental to human health, reported to cause asthma, back pains, bronchitis, chronic dermatitis, DNA damage, and even cancer - potentially impacting garment workers handling them, along with communities near to factories. Some reporting finds tannery workers have a 50% higher risk of pancreatic cancer linked to chemical exposure. Due to the pollution impact, industrial areas of China where leather is tanned are even referred to as “cancer villages” by news outlets.
When shopping for leather, look for ‘chromium-free’ tanning, along with the Leather Working Group (LWG) label, as LWG addresses environmental issues like the use of harmful chemicals such as chromium, effluent treatment, and also promotes traceability. In addition, look for farmers that use regenerative practices and have transparency in their leather processes, like Range Revolution.
What are alternatives?
Due to the various implications of fiber types, there are companies pioneering the space of developing new and innovative fibers, such as:
Bio-based leather alternatives
Algae and Seaweed fibers
Researchers from the Department of Sustainable Design Engineering at the Delft University of Technology investigated the use of algae in bioprinting by encapsulating microalgae within a non-living matrix (bacterial cellulose) using environmentally friendly chemistry. The bioprinted, photosynthetic materials were able to survive for up to 3 days without nutrients, with their lifetime extended by providing nutrients regularly. In addition, they are regenerative and can thereby be reused and expanded with additional living materials. The researchers are confident this application can be upscaled to photosynthetic bio-garments
SeaCell is a mixture of cellulose and seaweed. The most impressive aspect of this fiber is the high antioxidant count within its layers can help the body fight free radicals and prolong the effects of aging, while the silver within SeaCell Active has anti-microbial, anti-bacterial and anti-odor properties. These properties make it optimal for workout wear and underwear.
However, be aware of ‘bio-based’ plastics, as more research is needed to see if they are less toxic than regular plastics, as they need similar chemicals to turn them into fiber (see more about this here).