The Competition and Markets Authority (CMA) said Friday it has launched a review of environmental claims made by fashion companies, making the sector its first priority in efforts to tamp down on misleading sustainability marketing.

Big fashion brands are increasingly using eco-friendly claims to promote their products, responding to consumer appetite for more ethical purchases. But those claims are also facing growing scrutiny. The Netherlands is also investigating the validity of the apparel sector’s sustainability marketing.

The CMA’s review follows its publication of a new set of guidelines for green marketing in September. The organisation is now looking at how sectors measure up, starting with fashion.

“Our work so far indicates that there could be issues with greenwashing in the fashion sector and that’s why we’ve prioritised this area for further investigation,” Cecilia Parker Aranha, the CMA’s director of consumer protection, said in a statement. “Now is the time for the fashion industry to take a fresh look at what they’re telling customers and make any changes needed to comply with the law. Businesses that can’t back up their claims risk action from the CMA and damage to their reputation in the long-run.”

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