Experts discuss ways to be sure the produce you're eating won't make you sick.
By Richard Sine
WebMD Weight Loss Clinic - Feature
Reviewed by Louise Chang, MD
News about severe illness and even death from contaminated produce has some Americans spooked. Doctors and health experts have told us for years that eating vegetables is key to our health -- and now this news seems to be casting doubt on the safety of our food supply. Food safety advocates are calling for greater regulation, and the FBI has even started a criminal inquiry in the spinach scare.
It's time for a little perspective. The bad consequences of Americans eating their fruits and vegetables are dwarfed by the bad consequences of not eating them. Look at the numbers: An estimated 325,000 hospitalizations and 5,000 deaths result from food-borne illness each year from all causes. That's a lot, sure. But compare that to 479,000 deaths annually from heart attacks, 158,000 from stroke, and 224,000 from causes traceable to diabetes. All of those problems are associated (though not directly in all cases) with poor diet and obesity.
Nonetheless, even one serious illness or death resulting from negligence by food suppliers is a tragedy. And certain groups -- very young children, the elderly, people with compromised immune systems, and pregnant women -- are especially vulnerable to the effects of nasty microorganisms.
The produce scares demonstrate that it can be difficult to stamp out all the risk associated with consuming a raw, natural product. Some experts believe new technologies can help reduce the risks; others say stricter regulation is required. In any case, consumers can do a lot to reduce the risk to their families by choosing safe food and then handling it safely.
"The data shows that educating consumers on safe food handling has reduced the extent of food-borne illness," Shelley Feist of the nonprofit Partnership for Food Safety Education tells WebMD.
In this article, we'll discuss some of the risks exposed by the latest food scares and reveal some not-so-obvious tips for ensuring your family stays safe.
It's Not Easy Being (a Leafy) Green
Nearly 200 people around the U.S. were infected, 102 were hospitalized, and three died after eating bagged spinach contaminated by a virulent E. coli strain knows as 0157:H7 in August and September, say federal authorities. The three who died were two elderly women and one 2-year-old child, highlighting the stronger impact of contamination on vulnerable groups.
The FDA lifted its recommendation to avoid bagged spinach in early October. But just when things looked about ready to settle down, on Oct. 9 a lettuce company recalled 8,500 cartons of green leaf lettuce sold under the Foxy label after high levels of a generic form of E. coli were found in irrigation water.
The spinach outbreak was the 20th time lettuce or spinach has been blamed for an outbreak of illness since 1995, by the count of the Associated Press. So what's wrong with leafy greens?
Leafy greens are more prone to contamination than some other agricultural products, Sam Beattie, PhD, a food safety expert at Iowa State University, tells WebMD. Contamination is typically caused by fecal matter. And because lettuce grows close to the soil, it can be contaminated by any animals that "overfly, graze, slither, crawl, and are otherwise naturally present in a field."
Destroying harmful bacteria that get on a leaf is another challenge. Bacteria can be destroyed by heating or cooking, but most people prefer their greens raw. So Beattie and other researchers are experimenting with chemical treatments such as chlorine that can decontaminate while preserving freshness.
It's almost impossible to ensure that there will not be any disease-causing organisms on any agricultural product, Beattie says. So it's important to prevent any remaining organisms from multiplying to the point that they can make you ill. As bacteria need warmth and moisture to grow, the key is to ensure that produce remains cool and dry until it's eaten. Many of the same measures that ensure freshness also ensure safety.
Some advice from Beattie on choosing the right packaged greens:
- Look for signs of deterioration in the product, such as brown or wilted leaves, moistness in the bag, or swollen bags.
- Look for the latest possible "sell-by" date.
- Once purchased, keep the product refrigerated.
- Washing with cold running water will do little to remove more bacteria, but it will freshen the product, Beattie says. (Food safety experts recommend thoroughly rinsing all unpackaged fresh fruits and vegetables before eating.)
Weak Link in the Food Chain
Federal agencies depend on growers to police themselves, says Douglas Powell, PhD, scientific director of the Food Safety Network at Canada's University of Guelph. For the most part, it works. Growers test their irrigation water for contamination, maintain good employee sanitation, use properly composed manure, and take other measures.
The testing is what led the Nunes Company of Salinas, Calif., to recall Foxy brand lettuce on Oct. 9. The recall occurred before anyone got sick, and food safety experts applauded it as a good example of self-monitoring by a grower. "We're looking for the industry to be proactive for the sake of public health and consumer safety," Jack Guzewich, director of emergency coordination and response at the FDA's Center for Food Safety and Applied Nutrition, tells WebMD.
Pros and Cons of Self-Policing
The problem with self-policing is that "with a commodity like lettuce or spinach, you're only as good as your worst grower," Powell tells WebMD. And "the industry has done a lousy job in providing verification data" in terms of which growers are following proper practices.
Powell believes consumer standards and litigation will convince the industry to shape up without further regulation. Others are not so sure. "Asking people to do things voluntarily makes no sense," Marion Nestle, PhD, a food safety expert at New York University and author of What to Eat, tells WebMD. "The only way to do it is federal regulation. And when you have federal regulation it's been reasonably effective."
Nestle cites the beef industry as an example of successful regulation. In 1993, hundreds fell ill and four children died after eating undercooked hamburgers at Jack in the Box restaurants. The Agriculture Department tightened safety standards, and in 1996 it introduced a system that requires identification of the vulnerable points in the production chain and monitoring of those points. The result has been a decline of nearly one-third in E. coli cases from a decade ago.
Nestle believes the same system should be introduced for raw produce. She also believes that a single agency should be charged with all food safety, a job currently split between several different agencies. "You want standard food safety procedures introduced from farm to table," she tells WebMD.
Carrot Juice and the 'Cold Chain'
As of Oct. 13, seven cases of botulism from carrot juice had been reported -- four in the U.S. and three in Canada. In the U.S. the cases had been linked to Bolthouse Farms in Bakersfield, Calif. In all but one of the cases, the botulism has led to paralysis or respiratory failure. Bolthouse Farms has recalled the juice, and the FDA has urged people to discard Bolthouse juice in 450-milliliter and 1-liter plastic bottles with a "best if used by" date of Nov. 11 or earlier.
Botulism is caused by ingestion of a toxin produced by a bacterium, Clostridium botulinum, commonly found in the soil. Pasteurization may not kill all the C. botulinum spores, but the bacterium requires a warm environment to produce the toxin. Failure to refrigerate juice anywhere along what's known as the "cold chain" -- from the processing plant, to the warehouse, to the delivery truck, to the store, and to the home -- can allow botulism spores to multiply to lethal levels.
In at least one case, the botulism victims did not properly refrigerate the juice, says the FDA's Guzewich. In other cases, they apparently did. Investigations of the botulism cases and of Bolthouse Farms are still ongoing, Guzewich says. (Failure to refrigerate must occur over several hours or days, not just a few minutes, he adds.)
Labels About Refrigeration
If improper refrigeration at the home were to blame, then it may revive a debate on the adequacy of refrigeration labeling. Products that must be kept refrigerated for safety typically carry a "Keep Refrigerated" label, while products that only need refrigeration to retain quality carry the "Refrigerate After Opening" label. It may not be clear to consumers when refrigeration is voluntary and when it is mandatory, says Guzewich. He suggests clearer labels such as "Must Refrigerate to Maintain Safety" and "Refrigerate for Quality."
Another solution would be to require juice makers to change the acidity of their juice, which would make refrigeration unnecessary. In the 1980s, after cases of botulism were traced to chopped garlic that had not been refrigerated, the FDA required garlic makers to add phosphoric acid, says Robert Tauxe, MD, chief of food-borne diseases at the CDC. The challenge is in adding an acid to a food product without changing flavor, Tauxe tells WebMD.
As a microbe hunter, Tauxe is intimately familiar with every weakness in the food supply chain. But he says that doesn't keep him away from the salad bar. "We think it's important to eat a diet with lots of fruits and vegetables in it. Further work needs to be done to ensure produce is as safe as we want it to be. I'm continuing to eat the produce I've always enjoyed and I'd encourage everyone to do the same."
Published Oct. 3, 2006.
SOURCES: Robert Tauxe, MD, chief, food-borne diseases, CDC, Atlanta. Marion Nestle, PhD, professor of nutrition, food studies, and public health, New York University. Jack Guzewich, MPH, director of emergency coordination and response, Center for Food Safety and Applied Nutrition, FDA. Douglas Powell, PhD, associate professor of diagnostic medicine and pathobiology, Kansas State University, Manhattan, Kan.; director, Food Safety Network, University of Guelph, Ontario, Canada. Shelley Feist, executive director, Partnership for Food Safety Education, Washington, D.C. FDA web site. CDC web site. WHO web site. Associated Press.
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