A team of scientists from UC Davis will begin a four-year study of the sources of E. coli O157:H7 contamination in the Salinas Valley before the end of the yar, according to an univeristy press release. The USDA and UC Davis have been planning the study, which is funded with a $1.2 million grant from the USDA, for four years.

This study was designed before the late summer 2006 outbreak of E. coli O157:H7 associated with spinach. Several previous outbreaks of the virulent bacteria were associated with contaminated Salinas Valley lettuce.

In the first two years of the study, crews will collect thousands of samples of domestic animal and wildlife droppings; creek, ditch and irrigation water; farm soil and lettuce growing on Salinas Valley farms. The data collected in the field will be carefully analyzed to identify the vertebrates that are sources of E. coli O157:H7, assess the climate, landscape attributes and irrigation management practices that are correlated with increased risk of contamination, and determine whether contaminated lettuce is associated with certain farming practices or environmental factors.