Farms in California's Salinas Valley are being evaluated to determine why leafy greens grown in the area are linked with E. coli.
U.S. and California officials say lettuce and spinach grown in that area -- often called the "Salad Bowl of the World" -- has been identified in eight of 19 outbreaks of the virulent E. coli O157:H7 strain since 1995. The outbreaks have sickened at least 217 people in eight states, including two who died at a retirement home in Northern California in 2003, The Los Angeles Times reported.
Much of the nation's lettuce is grown in the valley and growers fear continuing infections might erode confidence in their $2 billion annual lettuce crop.
Inspectors told the Times the evaluation started last month and will continue through the fall.
Copyright 2006 by United Press International
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