FDA says cows may have caused E. coli lettuce contamination
Federal officials say cows grazing near romaine lettuce fields in California's Central Valley may have caused outbreaks of E. coli illness that sickened 188 people in the U.S. and Canada last year.
Thursday that suggested the three outbreaks were linked to fields in the Salinas Valley near cattle grazing areas.
Cow feces can contain E. coli that can contaminate water and soil through water runoff, winds or being tracked to the farms by people or animals.
The FDA said it hadn't identified the actual contamination route.