STYLE is supposedly for ever. But the garments needed to conjure up eternal chic are spending less time on shop racks and in homes than ever before. Global clothing production doubled between 2000 and 2014, as apparel firms’ operations became more efficient, their production cycles became quicker and fashionistas got more for their money. From just a few collections a year, fast-fashion brands such as Zara, owned by Spain’s Inditex, now offer more than 20; Sweden’s H&M manages up to 16.

Dressing to impress has an environmental cost as well as a financial one. From the pesticides poured on cotton fields to the washes in which denim is dunked, making 1kg of fabric generates 23kg of greenhouse gases on average, according to estimates by McKinsey, a consultancy. Because consumers keep almost every type of apparel only half as long as they did 15 years ago, these inputs quickly go to waste. The latest worry is shoppers in the developing world, who have yet to buy as many clothes as rich-world consumers but are fast catching up (see chart).

Most apparel companies know that sooner or later, consumers’ awareness of this subject will rise. That is a worry. Various furores in the 1990s and afterwards over the working conditions of people making goods for firms such as Nike, Walmart and Primark badly damaged brands. The clothing industry cannot afford to appear so ugly again. One obvious way in which firms can answer environmental concerns is to use renewable energy to power their facilities. Beyond that, they can cut back sharply on water and chemical use; and they can develop new materials and manufacturing processes that reduce inputs. The record in this regard is mixed. H&M was the largest buyer in the world of “better cotton” last year—that is, cotton produced under a scheme to eliminate the nastiest pesticides and encourage strict water management. It grows in 24 countries and represents about 12% of the 25m tonnes of cotton produced each year globally. Kirsten Brodde of Greenpeace also notes that H&M has eliminated toxic per- and polyfluorinated chemicals from its lines (which are used to make garments waterproof). Nike’s Flyknit method of weaving items, including trainers, reduces waste by 60% in comparison with cutting and sewing. Flyknit products have a large following: revenues from the line came to more than $1bn in the last fiscal year. But for many firms, research and development into new materials and methods is not a priority. Plenty do not measure their overall environmental impact. And introducing green collections can even carry a risk for brands, reckons Steven Swartz of McKinsey. It is possible that a shopper will move on from wearing a consciously green T-shirt to viewing other kinds of clothing as the trappings of planetary destruction.

A handful of brands encourage customers to recycle old clothes by returning them to stores. But almost all apparel today is made of a mix of materials—very often including polyester. Separating them out is difficult and mechanical methods of recycling degrade fibres. Chemical methods are too expensive to be viable. Shipping second-hand clothes off to countries in Africa and Asia is also a bust. Even if local markets are large enough to absorb them, the poorer quality of polyester-mixed garbs means they do not survive long.

More durable apparel could help. Tom Cridland, a British designer, creates men’s clothing that is designed to last three decades thanks to strong seams and special treatments to prevent shrinking. He expects revenues of $1m this year, but admits that his model will be hard to scale. Patagonia, a maker of climbing and hiking gear, sends vans to campuses to help students patch up jackets and trousers. It helps others with greenery, too. After discovering a type of material for wetsuits that, unlike neoprene, requires no oil to make, Patagonia shared the find with surfing brands such as Quiksilver. Such innovation is badly needed. Style may be forever but today’s model of clothing production is not.