Clothing and footwear firms including Nike, Marks & Spencer, Levi Strauss and Walmart are among those backing a new tool designed to measure sustainability and environmental impact across the industry supply chain.

The companies are members of the Sustainable Apparel Coalition (SAC), which yesterday (26 July) unveiled its new Higg Index to help identify opportunities to reduce impacts and improve long-term sustainability.

Other members of the Sustainable Apparel Coalition include Adidas, VF Corp, Arvind Mills, Li & Fung, TAL Apparel and H&M Hennes & Mauritz, along with non-governmental organisations, academic experts and governmental agencies.

The new index is based on established evaluation tools, including the Outdoor Industry Association's Eco Index and Nike's Environmental Apparel Design Tool.

It is designed to measure everything from water and energy use to greenhouse gas emissions, waste, chemicals and toxicity, and has been released after a year of beta testing the sustainability impacts of some 150 products from more than 63 companies.

There are plans for the next version of the index, set to be released in 2013, to include key social and labour metrics.

The SAC said the immediate priority of the Higg Index is to drive improvement and innovation in the global apparel and footwear supply chain by measuring environmental performance data from material sourcing through end of life.

"During months of pilot testing, we have already been able to use the Higg Index as an environmental indicator in the production of many of our products by all brands," said Adidas Group head of environmental cervices Karin Ekberg.

"We intend for the Higg Index to form an increasingly important part of our overall product creation and production strategy in the years to come."

Scott Lercel, director of social responsibility and sustainability at Target added: "This tool allows our teams to make better decisions, improve our supply chain and, most importantly, reduce our impact on the global environment."

However, the coalition said no timetable has yet been set for development of a consumer-facing label for products.