Bluish gray crusts lie on top of the soil of a corn field downstream from maquiladoras and industrial laundries, which dye and assemble jeans, in Tehuacan, some 230 km (143 miles) from Mexico City, April 25, 2007. Jeans factories have given jobs to thousands in the city of Tehuacan, the heartland of Mexico's denim industry, but they are pumping blue chemicals into rivers used to irrigate corn fields downstream. Picture taken April 25, 2007.
REUTERS/JENNIFER SZYMASZEK, STR