Wool is a popular material. It's warm for the winter, breathable for the summer and requires hardly any upkeep. Globally, wool accounts for 1.3% of all textile fibres, and is the most widely used animal fibre.

The environmental impact of wool

Of all the textile materials, wool is the biggest contributor to global warming (Source: Higg Index). Why does wool have such a big environmental footprint?

Heavy land demands

Sheep farming requires a lot of land to give the animals space and land to graze. Wool production, therefore, has a huge impact on land use worldwide. The UK Department for Environment, Food and Agriculture estimates that as much as 2278 hectares of land are needed per tonne of wool. This is particularly high compared to other materials. Cotton, for instance, only requires 1 hectare per tonne of cotton. Wool therefore requires a huge amount of agricultural land, something which is becoming scarce today.

Harmful greenhouse gases

Sheep, goats and alpacas emit large amounts of methane - a greenhouse gas - into the air. A sheep produces, on average, 30 litres of methane per day… a huge amount! New Zealand's sheep population is responsible for 90% of the country’s generation of methane (Source: Peta).

Did you know that methane’s greenhouse effect is 25 times stronger than CO2’s? Larger volumes of CO2 are being produced, however, making it a greater threat to the planet than methane. Another greenhouse gas also escapes from animal manure: nitrous oxide. This greenhouse gas is as much as 310 times (!) stronger than CO2. Livestock farming is therefore one of the biggest causes of global warming due to all of these greenhouse gases.

A lot of chemical pollution

Before the wool can be processed into a textile, it must be cleaned, to remove all dirt and any possible diseases, using chemicals.

Fortunately, wool fibres bleach easily, limiting the use of bleach. But this is not the case with every kind of wool. Alpaca wool is harder to bleach than other wools. As a result, more chemicals are needed, increasing its environmental impact. If we look at the amount of chemicals that end up in water with alpaca wool, it is 14 times (!) more than with ordinary sheep.

How can wool's environmental impact be reduced?

Wool’s environmental impact is reduced when the wool is taken from animals in the meat industry. This means raw materials are used more efficiently as the same animal is used for both wool and meat production. But not all sheep can produce both wool and meat. Older animals’ wool is less fine, so only young animals’ wool can be used.

To guarantee animal welfare, however, it is important that the animals are treated well by the meat industry which, unfortunately, cannot always be guaranteed.

Does animal-friendly wool even exist?

Wool is not the most animal-friendly product. Multiple scandals have highlighted the poor conditions in which the sheep are often kept. Soft merino wool from Australia and New Zealand is much loved in the West, but few are aware of the malpractices that are behind it.

Animal-UNfriendly mulesing

To produce as much wool as possible, humans have bred merino sheep so that they produce as much wool as possible. How have they done that? By increasing the sheep’s skin area. The issue is that this extra skin also makes the animals more vulnerable to Flystrike. This is a disease in which carnivorous larvae nestle between the warm skin folds. The flies first lay eggs in the thick skin, which then become these flesh-eating larvae.

To prevent this disease, farmers use ’animal-unfriendly’ mulesing. Mulesing is when the skin is cut away from the sheep’s breech, without the use of anaesthetic, to prevent these carnivorous larvae.

A more animal-friendly, but more labour-intensive process is to regularly check the fleece and use insecticides. This alternative requires much more manpower, which is unfortunately not possible on large farms and in industrial sheep farming.

Most wool used in clothing is mass produced in New Zealand and Australia. There are 70 million sheep scattered across several large sheep farms in Australia. Limited manpower on these large farms prevent farmers from choosing the more animal-friendly option instead of mulesing.

Are organic sheep better off?

Unfortunately, animal welfare is not guaranteed in organic farming either. More attention is, nevertheless, paid to animal welfare in organic farming than in conventional farming In organic farming, sheep are given organic feed and the farmer respects quotas for the number of animals per area, so the sheep definitely have enough free space. There are some benefits then, compared to industrial animal farming.

Which labels should you be looking out for?

While global wool production has declined in recent years, we are seeing a rise in the market share of more sustainable alternatives, which is good news!

Responsible Wool Standard (RWS)

The RWS has a list of criteria, focused on animal welfare, that purchased wool must meet. Clothing brand Patagonia established this certificate after several scandals involving an Argentinian sheep farm were uncovered by PETA. Today, several other companies have already joined including H&M and C&A.

It is one of the most widely used labels for wool products. In 2018, the RWS was used by 278 farms across 6 countries. South Africa led this with 133 certified farms, followed by Uruguay (69 farms), Argentina (39 farms), Australia (31 farms), New Zealand (5 farms) and the United States (1 farm). Unfortunately, RWS wool still only accounts for less than 1% of total wool production today.

Responsible Mohair & Cashmere

After the launch of the RWS for wool in 2016, several other related labels were developed: the Responsible Mohair Standard (RMS) and Responsible Cashmere Round Table (RCRT) came into being in 2019. This aims to ensure animal welfare in angora and cashmere goats as well. In Mongolia today, 3% of all cashmere is sustainably certified. A step in the right direction.

QZ label

In New Zealand, you will find the QZ label, which is similar to the RWS. This certificate also has a list of criteria to ensure sustainable and animal-friendly wool production. The QZ label covers 1% of total wool production worldwide, similar to the RWS.

Over the past 2 years, the QZ label has invested 1.6 million New Zealand Dollars into research and development. This is important progress as most of the mass produced sheep's wool comes from New Zealand, after Australia.

Labels are not a 100% guarantee

Despite labels, due to today’s long and complicated supply chains featuring many intermediaries, it is difficult to be able to 100% certify that all the wool in an item of clothing was produced in an animal-friendly way. One World warns that it is too early today to make any statements on whether these sustainable wool labels are really guaranteeing animal welfare.

There are also questions as to how accessible this label is to smaller brands and sheep farmers who don’t have the money to be certified despite treating their animals with respect.

Animal welfare remains a difficult issue to resolve, and labels are only a part of the solution.

What would be a better solution? Smaller supply chains, fewer intermediate suppliers and direct contact with wool farmers could bring more transparency to the sector.

Different types of wool

Merino wool

Did you know that there are several other types of wool besides classic sheep's wool? Merino wool comes from merino sheep. It is particularly loved for its extra-fine fibres, which make your clothes particularly soft. In general, the finer the fibre, the softer the product.

Merino wool is slightly more expensive though because it takes longer to grow, compared with other species of sheep. More wool from a finer fibre is also needed to make the same item of clothing. In addition, more delicate fabrics, such as merino wool, require a more labour-intensive production process.

Alpaca wool

Alpaca wool is incredibly soft, softer than merino wool. It is also 3 times stronger and 7 times warmer than sheep's wool. Perfect for people who feel the cold easily. Alpacas come from South America (mainly Peru, but also Bolivia, Argentina and Chile).

Alpaca wool is a good alternative if you are allergic to wool wax (lanolin). Sheep secrete this natural wax to repel water, dirt and bacteria, but some people are allergic to it. Alpacas do not produce lanolin, so alpaca wool can be a hypoallergenic alternative.


Cashmere does not come from sheep, but from goats! Goats live in Mongolia, China, India and Pakistan. They have a soft undercoat, which they lose once a year. Compared to other animals, the yield per goat is particularly low.

Their undercoat only weighs 150g, which is much less than the average sheep who can produce 3kg of wool in a year, or an alpaca that produces up to 5kg of wool. Cashmere is thus a rarer product, which explains the higher prices.


Like cashmere, mohair comes from goats, specifically angora goats, not to be confused with angora rabbits. Half of all mohair worldwide is produced in South Africa. Both the undercoat and the top coat are used for mohair wool, giving the wool its typical fluffy appearance.

Mohair fibres are slightly thicker than merino fibres. They’re long and smooth, making your jumper or scarf feel nice and soft and shiny.

Check out the following table for an overview of all the different types of wool and their environmental impacts!