E. Coli Spurs Review of Lettuce Farms

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Times Staff Writer

Federal and state officials have launched a wide-ranging evaluation of lettuce farming and processing in the Salinas Valley, hoping to determine why leafy greens grown here over the last decade have been linked to a potentially deadly strain of E. coli.

Lettuce and spinach grown in the valley, dubbed the “Salad Bowl of the World,” have been connected to eight of 19 outbreaks of E. coli O157:H7, associated with such produce since 1995. The eight outbreaks have sickened at least 217 people in eight states, including two who died at a retirement home in Northern California in 2003.

“That organism is so virulent, it is particularly dangerous,” said Robert Brackett, who directs the food safety division at the U.S. Food and Drug Administration, which is leading the investigation.

The recent inspections, which started in late August and will continue through the fall, come after nearly a year of heightened pressure from FDA and state officials to reduce the risk of E. coli contamination. The agencies’ concern was intensified when at least 34 people in Minnesota were sickened last year after consuming packaged Dole salad from the Salinas Valley.


The valley grows the vast majority of the nation’s lettuce, thanks to the region’s relatively cool climate. Though the outbreaks thus far appear not to have affected sales, some experts say continued reports of infection could erode confidence in the $2-billion-a-year lettuce industry. In addition, such problems can be a liability for produce distributors and food establishments that serve the greens.

One lawyer, Bill Marler, has represented more than 70 clients in cases linked to Salinas Valley lettuce, with settlements he described ranging from the tens of thousands to millions of dollars.

“We dare not make a mistake,” said Bob Martin, general manager of Rio Farms, who while giving a tour of his company’s expansive lettuce fields bit into some just-harvested leaves. “It could be the difference between staying in business and losing all your contracts.”

Martin and other industry officials said they welcome the review. In addition, in April the industry adopted voluntary guidelines on sanitary practices for lettuce growers and processors.

“We’re definitely sympathetic to anyone who has gotten sick or died,” Martin said. “But we don’t understand where ... it’s coming from.... I don’t know what else we can do.”

Such comments don’t satisfy Lori Olson, a Minneapolis mother whose two daughters were sickened with vomiting and diarrhea last year in the Dole lettuce outbreak.


“People have been getting sick for years from produce grown in this area, and people have died, and it’s still going on,” said Olson, 36, who added that she received a settlement from Dole but declined to disclose the amount.

Her youngest daughter, Amber Brister, now 13, suffered kidney failure and was hospitalized, missing two months of school. Though Amber has been doing well recently, she still gets tired easily and may someday need a kidney transplant, her mother said.

Produce need be contaminated with only a small quantity of E. coli for a person to fall ill. The O157:H7 strain, which lives in the intestines of healthy cattle and is present in manure, is passed to humans if they ingest the bacteria. Once eaten, it can produce a powerful toxin, leading to bloody diarrhea and, in rare cases, kidney failure.

The strain was associated in the 1990s with contaminated, undercooked hamburger meat served at Jack-in-the-Box restaurants and unpasteurized Odwalla apple juice. Odwalla sales plummeted after a 1996 outbreak killed a baby girl and sickened more than 60 others. The company paid a $1.5-million fine after pleading guilty to 16 misdemeanor criminal charges filed by federal prosecutors.

Ground beef can be grilled longer to kill E. coli and juice can be pasteurized, but a freshly tossed salad can’t be baked or boiled.

Moreover, though health and agricultural officials have spent years trying to trace the precise source of the contamination -- whether it be tainted water, infected animals or workers -- it remains a mystery.

Trace-backs, as they are called, are complicated by the fact that it can be weeks before an infected person is properly diagnosed and even longer before public health officials determine that there is an outbreak. By the time investigators find the original farm, the field has probably already been plowed under for a new crop.


“Despite lengthy resource-intensive investigations by state and federal agencies, no smoking gun has been identified,” wrote Jeff Farrar, a food safety official at the California Department of Health Services, in an e-mail to The Times.

The Salinas Valley has been implicated because the E. coli has been traced in some cases to sealed bags of greens grown and distributed from there, said the FDA’s Brackett, so the probable source of contamination would be in the field or during processing.

The recent inspections are not connected to any specific outbreak but are intended to allow observation of ordinary growing and processing practices to perhaps find some clues.

“It would give our investigators a better idea of the total picture ... a way to put the pieces of the puzzle of where any kind of contamination could come from,” Brackett said.

One hypothesis: Birds and other wildlife might be feeding on cow manure droppings, which fall into streams that flood nearby fields. One bird’s droppings might contaminate a single head of lettuce, used for multiple bags, growers and officials said.

Other potential risk factors include contaminated workers, tainted dust from a nearby cattle field and manure in compost.


“The best guess we can come up with: There are a group of circumstances that come together that allow it,” Brackett said.

In a 2005 state report, officials said E. coli had been found in the sediment of a creek bordering a flood-prone field that had been implicated in three outbreaks. But the E. coli found in the creek did not match any of the outbreak strains.

Pressure on the industry has increased since the Minnesota outbreak. In an unusual rebuke to lettuce growers and packers, Brackett wrote in an open letter in November that although “food-borne illness investigations rarely pinpoint the point of origin of the contamination ... claims that ‘we cannot take action until we know the cause’ are unacceptable. We believe that there are actions that can and should be undertaken immediately to address this issue.”

In January, California Public Health Officer Mark Horton wrote a letter to the Western Growers Assn., saying he has ordered his staff to consider reassessing manure composting rules, as well as regulations on septic tank systems that may leak into canals bordering fields. In addition, they are mulling whether growers should be advised not to grow ready-to-eat crops in fields prone to flooding and assessing the enforcement of rules regarding workers’ access to portable toilets and hand-washing facilities.

Industry officials said the outbreaks should be viewed in context. Although one outbreak is one too many, “Frankly, we should be celebrating the food safety record when you consider the tens of millions of meals served daily,” said Matt McInerney, executive vice president for the Western Growers Assn.

On a recent foggy morning in his company’s fields, Martin said the lettuce industry has made substantial progress in increasing food safety in the last decade.

As he spoke, the complexity of the operation became clear. Nearby, a row of eight men in hairnets and latex gloves hunched over to slice heads of lettuce from the ground and tossed them onto a stainless steel counter perched atop a slow-moving tractor.


There, women in aprons stacked the lettuce in sanitized plastic crates. The lettuce then was sprayed with chlorine, which is tested regularly to ensure effectiveness. A few yards away was a tank of water with a sink, soap and paper towels. Nearby stood two portable toilets.

Lettuce slated for ready-to-eat bags was later unpacked in a chilled processing plant, where workers in lab coats soaked the produce, inspected it and ran it through machines that bathed it in a mixture of water, chlorine and citric acid three times to kill harmful bacteria, before it was spun dried and sorted by machine into sealed plastic bags.

“I understand the concerns of the FDA. They’ve got to protect the consumers,” Martin said. But, he said, “any animal or bird can carry it. How can you keep birds from flying over your field?”




Clean greens

The California Department of Health Services recently released guidelines for consumers regarding ready-to-eat, pre-washed bagged salads. Here are some tips:

* Wash it if the product is not labeled “washed,” “triple washed” or “ready-to-eat.”

* If lettuce or a leafy green salad is in a sealed bag or rigid plastic container labeled “washed,” “triple washed” or “ready-to-eat,” the product does not need additional washing, unless specifically directed on the label.


* Further washing is not likely to enhance the safety of ready-to-eat leafy green salads or lettuce. In the unlikely event that harmful bacteria are present, they are likely to resist removal or inactivation by further washing.

* There is a risk of contaminating ready-to-eat salads by dirty hands, sinks, colanders, pans and utensils, which may outweigh any benefit of additional washing.

If you decide to wash ready-to-eat lettuce and leafy green salads, you should:

* Wash your hands thoroughly with soap and warm water for at least 20 seconds.

* Clean the sink, colander, salad spinner and any utensils with hot, soapy water.

* Use cold running water to wash the salad.

* Dry the greens with a clean salad spinner or new paper towel.

* Never use detergent or bleach to wash fresh vegetables.

* Make sure the greens have been refrigerated.

* Throw away any lettuce or salad if it has touched raw meat, poultry, seafood or their juices.

Source: California Department of Health Services