industry s dirty secrets. reporter: on the banks of the pearl river mrs. leo expresses amazement at the transformation of the waterway he calls home. i can see what the pollution has done, he says. the water has turned dark and black. the river has sustained chinese civilization for ages, but civilization hasn t been kind to the river lately. turning it into a dumping ground for debris, even carcasses and industrial waste. upstream is shintao, blue jean capital of the world, with 200 million pairs sewn here every year. this satellite image from greenpeace shows the river from hundreds of dennen factories run black. if you look at the river bank here, it s simply covered in trash, a lot of it scraps of blue dennen. blue-jean-clad consumers around the world may have no idea how destructive denim production can