Leafy greens present growing threat of food-borne illness, researchers say

A growing threat for food-borne illnesses comes attractively packaged, is stunningly convenient and is increasingly popular with shoppers looking for healthy meals: ready-to-eat leafy greens that make putting together a green salad as easy as opening a bag.

Though beef and poultry are a more frequent source of food-related outbreaks than produce, the number of outbreaks tied to lettuce, spinach and other leafy greens, whether fresh-cut or whole, has been rising over the last two decades, according to the nonprofit Center for Science in the Public Interest.

On Tuesday, researchers with the group called leafy greens the riskiest food regulated by the , with 363 outbreaks linked to those foods from 1990 to 2006. (Meat is regulated by the U.S. Department of Agriculture.)

The largest and most severe of these outbreaks came in September 2006, when bagged baby spinach tainted by E. coli bacteria sickened some 200 people and left three dead in 26 states. Last month, salmonella detected in testing prompted the recall of 1,715 cartons of bunched spinach sent to a dozen states.

"For a long time, produce was considered a safe item," said Jim Prevor, editor in chief of the food safety blog perishablepundit.com. "But that's not really the case anymore."

Hoping to ensure greater safety and cut the number of food-related outbreaks, the Agriculture Department has launched hearings around the country aimed at developing national production and handling rules for leafy greens and other vegetables.

Although consumers can reduce their risk, such as by washing greens, experts say preventing outbreaks requires action by farmers and producers to avoid bacterial contamination at the source or during processing.

Greens are especially vulnerable for several reasons, including that they are grown so close to the ground -- unlike, say, fruit from trees _ and can be tainted by water runoff, a persistent source of contamination when it carries animal waste.

What makes fresh-cut greens more susceptible is also what makes them convenient: the cutting and bagging that eliminates much of the work of salad preparation. That processing allows pathogens to get into the leaves, where they can flourish. The machinery used and the mixing of greens from various farms contribute to those dangers, not unlike the risks associated with processing ground beef.

Even greens put through a chlorine wash can be contaminated.

"These items are grown outdoors in fields with dirt. It's probably impossible to grow them without contact with a food-borne pathogen," said Craig Hedberg, a professor at the University of Minnesota's school of public health.

That such healthy foods can cause illness when tainted should give urgency to efforts to improve the nation's food safety system and better eradicate contamination, advocates said.

"Consumers shouldn't change their diets to avoid these foods," said Sarah Klein, a staff attorney at the Center for Science in the Public Interest. "The bottom line is that consumers need help from the food industry and the FDA if they want to eat nutritious and safe foods -- which is why these products need to be safe when they arrive in consumer and restaurant kitchens."

The center's researchers found that six outbreaks of disease and 598 illnesses were linked to greens in 1990. In 2006, the most recent data available, there were 49 such outbreaks and 1,279 illnesses.

The 2006 E. coli outbreak prompted growers and handlers of leafy greens in California, where most of the nation's lettuce and spinach is grown, to adopt a voluntary plan calling for tougher safety rules and regular inspections. Arizona, second to California in greens production, followed.

Now, a similar safety agreement may be crafted for green handlers nationwide.

"What we're seeing right now is a response to what happened in '06," said William Marler, a Seattle lawyer who is a leading plaintiff's attorney in food-borne illness cases.

Among those stricken in that outbreak was Mary Ann Westerman of Mendota, Ill. After eating bagged spinach tainted by E. coli, she got sick with vomiting and diarrhea, suffered kidney failure and, three years later, still struggles with related health issues, said her daughter, Martha Porter-Fiszer.

"I had no idea what could happen when it's a serious pathogen," said Porter-Fiszer, of Park Ridge, Ill. "We ought to be able to have food without bacteria reach our store shelves."

Whether the safety moves in place in California and Arizona will work is open to question. Skeptics say they are little more than a public relations effort by an industry trying to battle bad publicity as the market for fresh-cut salads and fixings grows.

In addition, critics note that the mid-September spinach recall involved a company that has signed on to the California agreement.

"What they don't want is for people to perceive that bagged greens are a problem," said David Runsten of the Community Alliance with Family Farmers, a California-based group that supports family farmers. Runsten testified during the first round of the USDA hearings, held in Monterey, Calif.

Leafy green handlers say the September 2006 outbreak underscored a need for the industry to adopt tougher safety standards, and that they are even more committed to delivering safe produce to consumers. They say the regulations allow growers and handlers to operate under a standard that helps eliminate the contamination that causes outbreaks.

"The culture of the industry has changed. That's a sign of the program's success," said Scott Horsfall, chief executive of the California Leafy Greens Marketing Agreement. "The advantage of this program is it allows the industry to rally around a single standard."

Prospects for national safety rules geared toward larger farms have opened a divide between the big corporate growers and handlers and some smaller organic and family farms. Those farmers fear that new rules, even if voluntary, could add costs to their operations and put them at a competitive disadvantage while doing little to improve food safety.

"We're concerned that farmers we work with and represent will become second-class citizens in the marketplace," said Will Fantle of the Cornucopia Institute, a not-for-profit that advocates for small farmers. "We contend some of the bagged product is typically riskier than what you can buy at a farmer's market or directly from a farmer."

David Cleverdon, who grows organic greens at his Kinnikinnick Farm in Caledonia, Ill., said he already adheres to a number of rules to maintain his organic certification. So while he is concerned about the potential costs of new rules, he does not immediately balk at the prospect.

He said the problem is more with big corporate farms than small farmers like him.

"They're afraid of the PR and the liability," he said of big farm operators. "So they're trying to protect themselves at the expense of the small farmer. That's who usually is hurt."
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