From Washington, D.C., at a meeting of the American Chemical Society
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Many Mexican communities have drinking water laced with unsafe levels of arsenic and unappealing amounts of sand and other solids. To make the water cleaner, Norma Alcantar, a chemical engineer at the University of South Florida in Tampa and her colleagues are working on an environmentally benign filtering process based on a plant found all over Mexico: the nopal cactus or prickly pear.