The most common form of leather is bovine leather, which is made from the skins ('hides') of animals in the Bovidae family, most commonly domestic cattle, including cows, bulls, steers, and calves. Bovine leather is also sometimes referred to as simply cow leather.

The bovine leather industry insists their product is more environmentally friendly and sustainable than vegan alternatives... but the science tells a different story. 

Siobhan O'Sullivan, Senior Lecturer in Social Policy at UNSW, reports: "The Higg Materials Sustainability Index [MSI], measures the environmental sustainability of materials used in garment production. In 2017, cow leather received the worst ranking of any material."

This data was published in 'Pulse of the Fashion Industry', a 2017 report produced by the Global Fashion Agenda and The Boston Consulting Group, using Higg Index data supplied by the Sustainable Apparel Coalition (SAC). Exhibit 16, 'Cradle to gate environmental impact by material' (page 42), shows cow leather ranked as the material that caused the most harm to the environment, out of all materials assessed. 

Instead of being transparent and admitting to the environmental harm they cause, the industry lobbied for the score to be removed. In October 2020, Leather UK, the industry's own trade body, reported: "The global leather industry has formally asked the Sustainable Apparel Coalition (SAC) to suspend the score the nonprofit organisation applies to leather in its Higg Materials Sustainability Index (MSI)."

The SAC said no. Confirming the rejection in their own words, industry body International Council of Tanners stated: "The leather industry regrets that SAC will not suspend the MSI, pending the necessary improvements needed for the scoring of natural materials."

When lobbying to suspend the score failed, the industry funded their own lifecycle study. The Leather Working Group reported, "In October 2024 a new industry dataset was adopted [by the MSI] showing that the global warming potential of leather is reduced by 60 percent to 14.6 points – down from 36.8 points previously."\

The leather industry celebrated this as a turning point. One 4 Leather declared the revised score was "a pivotal moment for leather's reputation as a low-impact material". 

However, this was not independent science. It was the leather industry commissioning their own consultant. The score only dropped after the leather industry funded and submitted their own data.

What the independent science says: The new 2026 study: Environmental performance of bovine leather vs vegan alternatives

In 2026, a new peer-reviewed study titled 'Environmental performance of bovine leather and alternatives: a hybrid approach combining life cycle screening and assessment' was published in the journal 'Cleaner Engineering and Technology' by researchers at the 'Norwegian University of Science and Technology', with no competing interests declared. The researchers compared the environmental impact of eight footwear materials side by side:

Bovine leathers (cattle skin):

-Chrome-tanned

-Vegetable-tanned

Vegan leathers (fossil-based):

-Polyurethane (PU) 

-Polyvinyl chloride (PVC)

Vegan leathers (non-optimised/pilot-scale):

-Pineapple leaf fibers (PALF) (Partially bio-based)

-Cactus (Partially bio-based)

-Kombucha bacterial cellulose (KBC) (Bio-based)

-Mycelium (Partially bio-based) (Only included in the LiSET, not the LCA, due to data gaps)

The study consisted of two assessments: The Lifecycle Screening of Emerging Technologies (LiSET) and the Life Cycle Assessment (LCA).

The researchers concluded: "The LCA results reveal that bovine leather has the highest [most harmful] environmental impacts, fossil-based alternatives have the lowest [least harmful] impact, and biobased or partially biobased alternatives score in the middle range."