Tests find no harmful bacteria in Arizona romaine lettuce; source of last year's E. coli outbreak linked to irrigation water

FILE - In this Aug. 16, 2007 file photo, a worker harvests romaine lettuce in Salinas, Calif. U.S. health officials are declaring an end to a food poisoning outbreak blamed on romaine lettuce from California. (AP Photo/Paul Sakuma, File)
FILE - In this Aug. 16, 2007 file photo, a worker harvests romaine lettuce in Salinas, Calif. U.S. health officials are declaring an end to a food poisoning outbreak blamed on romaine lettuce from California. (AP Photo/Paul Sakuma, File)

YUMA, Ariz. (AP) - No pathogenic forms of E. coli or salmonella were found in samples of romaine lettuce grown late last year in Yuma, Arizona, according to a federal report.

Researchers collected 118 samples of romaine lettuce from Yuma-area cooling facilities in December, the Yuma Sun reported Thursday.

Tests did find one strain of E. coli, but the bacteria form was not one harmful to humans, the Food and Drug Administration said in its report.

The samples were collected at random intervals as crops arrived at cooling facilities. The agency said the testing aim to catch any tainted lettuce before it hits the market.

"This is really good timing for a report like this to give consumers confidence that they can eat romaine lettuce all across the country," said Paula Rivadeneira, a food safety specialist at the University of Arizona Cooperative Extension. "We already started planting, and so I think it's good news for the industry as a whole."

The tests followed an E. coli outbreak linked to romaine lettuce in spring 2018. The Centers for Disease Control and Prevention recorded about 200 people sickened and five deaths from the outbreak traced to Yuma.

Investigators determined the bacteria likely spread to multiple fields through tainted irrigation water.

Research needs to continue into ways to keep E. coli out of fields and to ensure testing will catch it if does reach the lettuce, said John Boelts, first vice president for vegetables at the Arizona Farm Bureau.

"What we don't know is our worst enemy, and it's imperative that we push forward with science," Boelts said. "And industry's leading that effort in collaborating with the university researchers and anybody else who's working on these."

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