Pulling The Wool Back From Our Eyes
While public awareness of the meat industry’s negative environmental impacts has increased considerably, the ecological implications of animal products in fashion are less well-known. Wool in particular is often viewed as a sustainable fabric, and tends to be marketed as “sustainable”, “natural”, and “biodegradable.” However, commercial wool production comes with its own collection of environmental baggage.
In collaboration with Collective Fashion Justice’s CIRCUMFAUNA Initiative, the Center for Biological Diversity has authored a report to shed light on the environmental impacts of wool. They integrated evidence from a variety of sources to calculate relevant statistics, including the Food and Agriculture Organization, government agency reports, industry reports, and scientific papers. The report has a particular focus on Australia and the USA, but you may find it useful as a starting point for researching wool production in your own geographical location.
Wool production encompasses sheep rearing, wool processing, and the waste produced from both processing and discarded wool clothing. As the sheep meat industry is intertwined with the wool industry, environmental implications of this slaughter industry are also relevant. Pure-bred merino sheep are used only for wool, but merino cross-breeds are used for both wool and meat. According to one sustainability scoring system (the Higg Material Sustainability Index), the climate cost of sheep’s wool is, on average, more than five times higher than conventional cotton and three times higher than acrylic.
First, the report outlines four different types of environmental impact accompanying the production steps, spanning sheep rearing through to shearing: greenhouse gas (GHG) emissions, land and water use and degradation, biodiversity loss, and pollution.
GHG emissions from greasy (unprocessed) wool vary across different wool production systems. In Australia, 8.9 kg CO2e (carbon dioxide equivalent units) are produced per kilogram greasy wool from prime lamb meat production, while 30.6 kg CO2e are produced per kilogram greasy merino fine wool from a single sheep (shorn multiple times throughout their life).
Land and Water Use & Degradation, and Biodiversity Loss
In Australia, 367 times more land is needed to produce a bale of wool compared to a bale of cotton. Land clearing & deforestation, grazing, and hoof compaction from hard-hooved animals like sheep contribute to land degradation, including severe forms: soil erosion and desertification. Case studies in Patagonia, Argentina, and Wooleen Station in Australia have demonstrated the positive ecosystem effects of “destocking” — removing sheep from areas of previously intensive wool production.
To supplement grazing, sheep consume conventional animal feed crops, which rely heavily on pesticides. Pesticide runoff damages water quality, as does manure runoff. Manure runoff also depletes the oxygen content of water through a process known as eutrophication, which is detrimental to aquatic species.
Sheep are non-native species in Australia and the United States. Grazing and associated land degradation put native wildlife at risk. Wildlife also compete with sheep for forage. In Australia, koalas and native bird species are especially threatened by land clearing. In the U.S., species such as bighorn sheep, desert tortoises, and grizzly bears are at risk. Bighorn sheep are susceptible to diseases carried by domestic sheep, and bighorn sheep showing symptoms are culled to prevent disease spread. Furthermore, wild animals are often killed if they are found on farmed land, especially if they have attacked sheep.
Pollution and Energy Use at Processing
Scouring is a standard step in the wool production chain, as 35-60% of freshly shorn wool is contaminated with impurities. These impurities include lanolin (a wax secreted by sheep skin), dried sweat, soil (dirt, dust, feces, vegetation), and pesticides used to prevent fly strike and lice. To cut the grease, strong detergents must be used. Significant water and energy usage are required to heat the water and run the machinery. Wool may also be carbonized (treated with additional chemicals and heat) if high amounts of vegetation are present.
Next, wool is submerged in a concentrated sulphuric acid solution, and baked dry. Typically, it is then brightened with bleach. Insect-resistant, moth-proofing chemicals are also often added.
The amount of liquid pollution produced at a typical wool scour facility (waste detergents and cleaning solutions) is similar to the amount of sewage waste produced by a town of approximately 30,000 people. The effluent produced does not biodegrade easily and has a high chemical oxygen demand, which reduces oxygen levels in the waterways it eventually flows into. Scouring detergents also contain endocrine disrupting chemicals, which can damage the fertility of both human and non-human animals. In addition, only 30% of this effluent is treated before being released into waterways.
More and more, wool is funneled into the fast fashion market, where it is typically woven into clothing with plastic-based synthetic fibers. Superwashed wool is also often used in fast fashion, where wool is coated in plastic resin to make it machine washable. Once blended with synthetics and/or superwashed, wool is no longer biodegradable.
An Industry In Decline?
Interestingly, the wool industry is in a decline, with its 2020 value at an all-time low compared to the past 50 years.
The report ends on a positive note, describing market opportunities for innovative materials free from both animal and plastic-based fibers (e.g., plant-based or lab-grown fibers). While such alternatives are likely to pose less harm to animals and ecosystems compared to wool or synthetics (which rely on fossil fuels and contribute to microplastic pollution), it is important to keep in mind that the research & development involved in preparing novel materials for market still requires large amounts of energy and entails large amounts of waste. Considering the current overabundance of clothing, reducing the purchase of new garments is important for both animal and environmental health.
Overall, this report provides a comprehensive overview of a seldom discussed topic: the sustainability concerns associated with wool. Activists may also find it useful for intersectional campaigns, as it provides information on the impacts of wool production on sheep welfare, linkages between the wool and sheep meat industries, and the dangerous, exploitative labor conditions of the commercial wool industry.