CFAES Give Today
News Releases Archive (Prior to 2011)

College of Food, Agricultural, and Environmental Sciences


Chow Line: When alarms sound, balance risk, benefits (for 9/10/06)

September 1, 2006

I got an e-mail saying prewashed, bagged lettuce might have E. coli. Is it a hoax?

Well, that's actually a tougher question than you might think.

Back in October 2005, the Food and Drug Administration did, in fact, issue a warning after E. coli O157:H7 was found in one brand of salad mix. The company issued a recall, but authorities documented illness among 26 people, primarily around Minneapolis-St. Paul. There were eight hospitalizations, including one 12-year-old who developed a serious kidney problem.

Given these facts, it's difficult to dismiss such warnings. But it's also important to use some perspective: The largest supplier of prepackaged salads sells 2.1 million bags daily in the United States, but the incidence of problems is extremely low. Most experts believe the benefits of regularly consuming a wide variety of fruits and vegetables, including pre-bagged salad mix if that's your preference, counterbalance the risk.

Unfortunately, E. coli can be anywhere. The microbes can live in the digestive systems of both humans and animals, and can spread through manure or improperly washed hands. Lettuce and other leafy greens grow very close to the soil -- processors realize the risk and rinse the greens several times before packaging, and they're taking additional steps to make their products even safer. If you decide against bagged salads in favor of lettuce you wash at home, be sure your hands, sink and counters are clean, and keep raw meats separated from foods that will be eaten raw.

Cooking foods -- hamburger, other meats -- is the traditional way to kill food-borne bacteria. Problems usually stem from not cooking foods thoroughly or exposing foods like lettuce or other fresh produce -(that you don't heat before consuming) to raw meats or their juices.

Of course, you should follow standard food-safety guidelines whenever you prepare food. As always, take special care for anyone who's more at risk -- young children, the elderly, or anyone with a compromised immune system.

Also, be aware that lettuce concerns are outweighed by those about alfalfa sprouts. After outbreaks in the late 1990s, microbiologists realized that the way alfalfa seeds are grown into sprouts provide ideal conditions for microorganisms, and rinsing sprouts doesn't get rid of them. Since 2002, the Centers for Disease Control and Prevention has recommended that children under 5, as well as adults who are immunocompromised or elderly, avoid eating alfalfa sprouts, period, until new processes can be tested to assure their safety.

Chow Line is a service of Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH, 43210-1044, or

This column was reviewed by Jeffrey LeJeune, microbiologist with the Ohio Agricultural Research and Development Center in Wooster.

Martha Filipic
Jeffrey LeJeune