In the ongoing debate over how safe the U.S. food supply really is, a new study shows getting back to nature may not be the answer.

Some experts believe organic foods may be riskier than conventionally grown foods because of potential contamination with E. coli, says a University of Georgia scientist.

E.coli O157:H7

"In many cases, 'organic' means the foods were grown with animal manures instead of chemical fertilizers," said Paul Guillebeau, an entomologist with the UGA College of Agricultural and Environmental Sciences. "Animal manure is the primary reservoir for a virulent strain of E. coli."

The Centers for Disease Control and Prevention confirmed nearly 2,500 cases of E. coli 0157:H7 in 1996. The CDC reported 250 deaths. While organic foods made up only 1 percent of the U.S. food supply, they were implicated in 8 percent of the E. coli cases.

Organic foods are also more likely to be contaminated with fungal toxins like aflatoxin, according to the U.S. Food and Drug Administration. Unpasteurized milk and juices are more likely to be contaminated with bacteria.

"Organic producers may make problems worse because they often don't use chlorinated water or other disinfectants before selling their products," Guillebeau said.

"I'm not condemning organic foods," he said. "The risks from pesticides may be reduced by consuming organically grown products. I just want people to realize that organic production doesn't eliminate food risks. It increases some risks."

Not all organic foods are grown with manure, said Cynthia Hizer. She is one of many organic growers who sells produce at the Morningside Farmers Market, an open-air market in Atlanta.

"Many organic farmers fertilize crops with 'green manure,' which is plant matter, as opposed to animal manure," Hizer said. "We all compost our manure in a heap where it is heated to a temperature that should kill most pathogens. We don't put it raw on the fields."

Hizer, who grew up on a farm in Indiana, supports organic farming for several reasons.

"You're building the soil and putting life back into the soil with organics," she said. "That adds vitality to the plants that are grown in it and more flavor in the food."

Food safety experts with the UGA Extension Service say it's not really how the food is grown that counts most. It's how safely you handle it in your own kitchen.

"There is a risk of E.coli with any food," said Connie Crawley, an extension food safety and nutrition specialist. "It's hard to trace the source of the contamination."

The study on E. coli in organic foods, she said, "just emphasizes that you should always wash any produce thoroughly in water."

Crawley agrees that the grower plays a role in food safety. But she sees the grower's role as minimal.

"Most organic farmers who are in it for their main business are aware of the risk," she said. "They take great care to reduce the risks."

The best place to avoid the risk of E.coli, she said, is between the market and the dinner plate. She offers this advice:

• Keep produce clean and stored appropriately.
• Keep your kitchen and storage area clean.
• Wash your hands and utensils before preparing foods.
• Think about how the food grows. If it grows up through the ground and has crevices, like lettuce or onions, wash it more thoroughly.

"There is no totally sterile food," Crawley said. "Someone who hasn't washed his hands can walk into a grocery store, pick up some produce and contaminate it. If you're going to eat raw food, you have to be aware."