The FDA says a cattle feedlot near an irrigation canal may be the source of the virulent E. coli in a 36-state outbreak linked to romaine lettuce from the Yuma, Arizona area. Months of investigation led the agency to the canal, and samples of its water have tested positive for the implicated strain. More than 200 people were confirmed to be infected in the outbreak; nearly half became so sick they had to be hospitalized, and five died. Federal officials declared the outbreak over on June 28. The agency says the feedlot in question "can hold in excess of 100,000 head of cattle at any one time and the FDA trace-back information showed a clustering of romaine lettuce farms nearby." Food Safety News reports the situation has prompted industry stakeholders to create the Leafy Greens Food Safety Task Force to review regional growing practices. Among its recommendations: tripling the buffer zone between feedlots and growing fields (from the present 400 feet to 1,200 feet). Members of the California and Arizona Leafy Greens Marketing Agreement are aiming to put new safety measures in place before the next planting season begins, in October. Most of the leafy greens grown in the US come from the Yuma region.