Food Safety News: Outbreak investigators say a cattle feedlot near a canal providing water to growing regions in Arizona is a key element in their hypothesis about the source of E. coli that contaminated romaine lettuce earlier this year. Five people died and more than 200 others were confirmed with infections from a particularly virulent strain of E. coli O157:H7 that investigators found in the canal water in June. Dust from such feedlots is a known vector for the spread of E. coli bacteria and other pathogens to growing fields and surface water.