Lettuce E. coli

Romaine lettuce is seen growing in this file image.

The U.S. Food and Drug Administration found no Yuma lettuce samples that tested positive for the pathogenic form of the E. coli bacteria or salmonella during last year’s produce season, according to a report released Wednesday. 

The verdict comes just as growers are preparing for their second produce season since a spring 2018 E. coli outbreak tied to 210 illnesses and five deaths shook the local agriculture industry to its core.

“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 in Yuma. “We already started planting, and so I think it’s good news for the industry as a whole.” 

The FDA report said one strain of shiga-producing E. coli was detected, but further tests revealed it was not a form of the bacteria that is harmful to humans, the federal agency stated in a report on the microbiological sampling done in the area. 

Researchers took 118 samples of romaine lettuce from 26 coolers and cooling facilities in the Yuma growing area beginning Dec. 17, the agency said, with the ultimate goal of catching any pathogens before the infected product made it to market. 

The FDA worked with the Arizona state departments of agriculture and health in collecting the samples, the report said. 

The 2018 outbreak was easily the worst tied to leafy green vegetables since the one linked to spinach grown in Salinas, Calif., in 2006, after which new food safety standards were adopted throughout the industry and had kept large-scale outbreaks at bay. 

Vic Smith, CEO of JV Smith Companies, said, “In an unusual or fairly once-in-a-while situation we have a problem, like we did in spring of last year. So I think that kind of sampling shows that our food safety practices, the vast, vast majority of the time, are doing the job and we’re focusing on those rare instances when we do have a problem, so we can prevent those.” 

An environmental assessment of the 2018 Yuma outbreak said irrigation water was the “most likely” way E. coli bacteria was spread and tainted multiple fields, after it was found in three samples taken from the Wellton-Mohawk irrigation district system.

It further theorized that a nearby stockyard could have been the source of that bacteria, but no environmental samples taken from it tested positive for pathogenic E. coli.

The lettuce was collected at random intervals as crops arrived at the cooling facilities, before they could be handled by workers. The FDA said this was done so the researchers could collect samples from multiple fields, and the product could be quickly traced back to the field it came from. 

This approach was criticized by some local growers, worried that a positive test result would come back after the rest of the crops from that field had already reached consumers in the marketplace.

“If they do find it and there’s a lag time to get the test results back, that product’s already in the chain of commerce, so that’s a horrible situation. If they want to do testing at the production level they need to devise some sort of program that doesn’t put us in jeopardy,” Smith said. 

The report did say the possibility of this happening was reduced by “many of the facilities opting to hold the product pending notification of test results.” But John Boelts of Desert Premium Farms in Yuma said doing that created other problems. 

“When you have the government show up and say they’re going to do a random, unannounced sampling program, that’s fine. Except for they did not make provisions for how to get the results from those samples promptly,” he said. 

The collected samples were overnighted to a lab in Colorado where it could be tested according to FDA protocols. This meant results could come back three or more days later, he said, especially if it ran over a weekend. 

Given how perishable leafy greens are, they sometimes were held back so long they couldn’t be sent to market or even donated to local food banks, increasing food waste while driving up prices. 

“I think they’ve learned now, but that is something that happened,” he said. 

Boelts, who is the first vice president for vegetables at the Arizona Farm Bureau, said the ultimate outcome of the testing is good news, but doesn’t eliminate the need for continued research into all the ways that E. coli can infiltrate a field, and how it can evidently evade detection by current testing methods. 

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

The FDA report said one reason the testing was done in Yuma last winter is the fact that five multistate outbreaks of foodborne illness since 2012 have either been conclusively tied to the Yuma area or suspected of originating there. 

The report did not give any additional information about the other four incidents. It said the information came from a search of the FDA’s Coordinated Outbreak Response and Evaluation (CORE) Network outbreak database. 

A spokesman for the FDA had not provided any additional information to the Sun about these incidents by 7 p.m. Wednesday. 

“I would like to know what that is all about,” Rivadeneira said.

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