Environmental concerns focus on a range of pollutants in that water, from pesticides on cotton fields to dust storms caused by overgrazing in Inner Mongolia by cashmere goats.

According to the non-governmental organisation (NGO) China Water Risk, it can take 40,000 litres of water to grow 1kg of cotton and 600 litres of wastewater can be produced to make just 1kg of textiles.

And the average Chinese apparel factory discards 27.2 tonnes of usable, pre-consumer excess textiles every week, which includes new thread, fabric, buttons and trimmings.

Greenpeace International's 2012 report on the impact of textile production in China found that hazardous waste included dye-related chlorinated anilines (which are toxic to a wide range of organisms and include known or suspected carcinogens); perfluorooctanoic acid (a highly persistent and bioaccumulative toxic chemical); nitrobenzene (carcinogenic in animals and possibly humans); and chloronitrobenzenes (used for dyes and are also suspected carcinogens).

In response, governments in the key rich world consumer markets for textiles and clothing are promoting materials recycling.

The European Union (EU), for instance, has been steadily expanding the scope of its recycling legislation, which now includes textiles in its guidance on end-of waste criteria.

It is also promoting innovation in the field. Last year, it invited proposals for a shortlist of 45 eco-innovation clean-up projects that would be eligible for EUR31.5m in funding. Materials including textiles are one of five key areas targeted by the proposal.

Customer and consumer pressure
For the most part, however, it is companies and customers that are driving moves to clean up. "There's legislation brewing in the EU, but it'll be a long time coming in the US given the make up of Congress," said Vincent Stanley, vice-president of marketing at California-based organic cotton clothing specialist Patagonia Inc.

"There are a lot of initiatives; the question is which is the most effective," said Dr Anne Bonhoff, global head of chemistry for US-based international safety science company UL.

"Some of the brands are really going down the supply chain, or at least looking to see how bad it is." Sweden's Hennes & Mauritz (H&M) banned perflourinated compounds in all products this year, for instance.

And one major multi-brand initiative is the Roadmap to Zero Discharge of Hazardous Chemicals (ZDHC), set up in 2011 by major apparel and footwear brands and retailers with the aim of eliminating hazardous discharges in the supply chain by 2020. Companies involved include Levi Strauss, Adidas Group and Inditex.

The group reports annually against a published 'joint roadmap' timeline. In June 2013, it received a boost when a revised, second version was published, overcoming some of the obstacles that had led to the original roadmap being withdrawn after demands from academics, regulatory agencies and environmental NGOs. These included a realistic reassessment of targets and the involvement of an increasing number of brands. 

"More brands are now involved and that is a good trend," said Dr Bonhoff. "So many brands are now involved that together they have power to go to producers and suppliers."

However, she said the initiative has to be realistic: "You can reduce discharges as much as possible but to reach zero by 2020 may not be possible."

Sustainable Apparel Coalition
Another key driver is the Sustainable Apparel Coalition (SAC). Launched in late 2010, it now has 82 members, it says representing one-third of global apparel and footwear production.

The coalition oversees the Higg Index, a designer-oriented database that enables companies to evaluate material types, products, facilities and processes based on a range of environmental and product design choices. These include materials, manufacturing, packaging, transportation, use and end-of-life, though not yet retail activities.

The coalition emphasises shared information and best practice: "It's mutually beneficial," said Stanley. "A lot of this work is so new - it's not a question of intellectual property."

One example of this seemingly commercial largesse was Nike's decision to disseminate the findings of its US$7m 'environmental apparel design tool,' which employs a numeric scoring system to environmental impacts such as materials, waste, and garment treatments.

Patagonia is also keen to disseminate best practice through its newly launched '$20 Million & Change' programme, an internal fund set up to help like-minded start-up companies. Patagonia Works (the holding company of Patagonia Inc) could be an investor or joint-venture partner, Stanley said.

Risk management
"Because of the Internet, companies are afraid of their reputation," added Stanley. "There's so much going on in the supply chain that is out of the control of the brands that they genuinely need to know more about what's going on to manage the public risks. If you are all using the same language, then you avoid a competitive race to the bottom [in standards]."

As for hazardous chemicals, US-based NGO the Natural Resources Defense Council (NRDC) has called for a ban on the application of silver nanoparticles as an odour-absorber for underpants and socks.

The council has also launched a garment-focused programme called Clean by Design, which focuses on improving efficiency to reduce energy, water and chemical usage. It has published 'Ten Best Practices for Textile Mills to Save Money and Reduce Pollution', a series of measures to curb pollution while saving factories money.

In another attempt to reduce the use of hazardous chemicals, Redress, a Hong Kong-based NGO, this year launched an international eco-chic design competition, to identify and encourage sustainable design among emerging designers.

"It sounds like a fluffy award, but it's underpinned by something quite real," said Dr Christina Dean, director of Redress.

"There are something like 100,000 garment manufacturers in China alone, producing around 28.5bn garments a year [according to the China Association of Resource Comprehensive Utilisation], and there is a massive hole in knowledge about sustainability. This is about educating designers - they are like a toxic bomb if they don't get it right."

Click on the links below to read other chapters in this briefing:
Green garments: Eco-labels - good or greenwash?
Green Garments: Sustainable practices in Asia
Green garments: Closed loop supply chains hard to achieve