The US Department of Agriculture has concluded the best way to kill all the bad stuff on leafy greens is to zap them with radiation. The LA Times reports that USDA scientist reported yesterday that "irradiation could be key to destroying pathogens in hard-to-reach places inside and on the surface of fruits and vegetables." (Above, spinach.)Irradiating fruits and vegetables, however, isn't currently allowed in the U.S. (Some meats are irradiated.) And although the USDA hasn't found any health effects from eating irradiated foods, consumer groups say the technique is unproven. One in four Americans suffer from a food-borne illness each year. The USDA study found that irradiation of leafy greens did a much better job of killing the bad bugs than rinses. "Irradiation kills E. coli where chlorine doesn't," said one USDA scientist.