Mariano Baragán looked down at the blue-grey crust peeling off the field he irrigates from a canal. Nearby factories were the problem - dozens of them, which are dedicated to doing to jeans in hours what used to take years of wear.
"As well as being blue, it burns the seedlings and sterilises the earth," the 67-year-old subsistence farmer said. And the cause? A wry smile hovered on his lips. "It's the fashion."