The exact source probably will never be found for the E. coli outbreak linked to fresh spinach, a top food safety official said Tuesday, though federal inspectors kept checking California farms and factories.
Food and Drug Administration inspectors were visiting fields and buildings linked to companies that have recalled fresh spinach products, as well as other locations in the Salinas Valley, said Robert Brackett, director of the agency's Center for Food Safety and Applied Sciences.
As of Tuesday, the outbreak had sickened 131 people in 21 states, according to the Centers for Disease Control and Prevention. One person died, and half those with the food poisoning were hospitalized, the CDC said.
The outbreak of E. coli is the 20th linked to fresh lettuce or spinach since 1995.
"I would say the odds are, based on past experiences, we will not be able to pinpoint the exact cause," Brackett said.
In particular, investigators seek evidence of flooding or cases where contaminated surface area had come into contact with crops, Brackett told The Associated Press. They also were on the lookout for animal droppings and other evidence of wildlife in the fields, as well as checking on the sanitary conditions inside the plants where produce is processed.
"They will look for any obvious or even suspected places where this organism could gain access to the produce," Brackett said. Inspectors also were taking samples from actual produce as well as from common areas in the processing plants that could harbor bacteria, he added.
The same questions about E. coli keep popping up, Brackett said. How long can the bacteria survive in the soil after a flood? Do the bugs live longer in some soils than others? Can leafy greens take up the bacteria internally, as is thought likely?
Meanwhile, Brackett said California growers needed to do more to eliminate contamination, even without identifying a precise source.
"What we would like them to do is take ownership of the problem," Brackett said, reiterating a call he had made in a November 2005 letter to growers. "The fact that this keeps coming up suggests that whatever has been done is not good enough."
Growers have said they have zero tolerance for bacterial contamination. California officials suggested the sheer volume of produce grown in the Salinas Valley could explain the outbreaks, rather than poor farming practices.
The FDA continued to warn consumers not to eat raw spinach.
Natural Selection Foods LLC, a San Juan Bautista company whose multiple brands many people reported eating before falling sick, has recalled spinach products distributed throughout the United States. The company also distributed spinach to Canada, Mexico and Taiwan.
Salinas-based River Ranch Fresh Foods recalled spring salad mixes containing spinach purchased from Natural Selection.
On Tuesday, a third company said it was voluntarily recalling salad mixes that may contain spinach supplied by Natural Selection. RLB Food Distributors LP, based in West Caldwell, N.J., said the recall included various salad mixes sold under the Balducci's and FreshPro brands and distributed on the East Coast.
