WASHINGTON – The government will allow food producers to zap fresh spinach and iceberg lettuce with enough radiation to kill microorganisms such as E. coli and salmonella that for decades have caused widespread illness among consumers.

The irradiation rule goes into effect today.

It is the first time the Food and Drug Administration has allowed any produce to be irradiated at levels needed to protect against illness.

"This is probably one of the single most significant food safety actions done for fresh produce in many years," said Robert Brackett, chief scientist for the Grocery Manufacturers Association, which petitioned the agency in 2000 to allow manufacturers to irradiate a wide variety of processed meats, prepared foods and fruits and vegetables.

The FDA still is considering the petition to allow irradiation of additional produce. The grocery manufacturers group will push for other greens, such as Romaine lettuce, to be next, so that producers could irradiate bags of salad mixes.

Food-safety advocates condemned the government decision and asserted that irradiation can lower nutritional value, create unsafe chemicals and ruin taste.

"It's a total cop-out," said Patty Lovera, assistant director of Food and Water Watch. "They don't have the resources, the authority or the political will to really protect consumers from unsafe food."

Dr. Laura Tarantino, director of the FDA's office of food additive safety, said the agency found no serious nutritional or safety changes associated with irradiation of spinach or lettuce.

"These irradiated foods are not less safe than others, and the doses are effective in reducing the level of disease-causing microorganisms," she said.

The government has long allowed food processors to irradiate beef, eggs, poultry, oysters and spices, but the market for irradiated foods is tiny because the government also requires that these foods be labeled as irradiated, labels that scare away most consumers.

"People think the product is radioactive," said Harlan Clemmons, president of Sadex, a food irradiation company based in Sioux City, Iowa.

But the FDA is presently considering a proposal to weaken or change this labeling requirement.

Caroline Smith DeWaal, food safety director at the Center for Science in the Public Interest, opposes weakening the present labeling rules.

Advocates for irradiation say the technology can help reduce the burden of illness and the number of outbreaks.

"Wegmans is fully committed to offering product that is safe to our customers," said Jeanne Colleluori, a spokeswoman for Wegmans, a supermarket chain based in Rochester, N.Y., that is the only major retailer of irradiated beef. If irradiated spinach and lettuce become available, Wegmans will "offer it as a choice so that customers can try it," Ms. Colleluori said.

But critics say that not only does radiation make food less nutritious and potentially toxic, it also does not eliminate the risks of food-borne illnesses. An analysis by the Center for Science in the Public Interest found that most outbreaks associated with salad and lettuce are caused by viruses – which are not affected by the doses of radiation approved by the FDA.

Indeed, food-safety advocates, food producers and even farm groups agree that the government should mandate the use of certain agricultural and processing practices that would limit the risk of all food-borne illnesses and increase the speed with which outbreaks are traced back to sources.

"The agency is choosing to have a high-tech expensive solution to a problem that needs a more thorough approach and one that really starts on the farm," said Smith DeWaal of the Center for Science in the Public Interest.

Government officials say they continue to study the science behind proposals to require good agricultural practices. In the meantime, irradiation could help, Dr. Tarantino of the FDA said.

"This is not a magic bullet," she said. "It's not a solution for everything. It's one more option that people can use. "

Current practices: Irradiated meat has been around for years, particularly ground beef that is a favorite hiding spot for E. coli. Spices also can be irradiated.

Likely participants: The industry group wouldn't name salad suppliers ready to start irradiating. But it expects niche marketing to trickle out first. California-based produce giant Dole Food Co. confirmed it is considering irradiated lettuce.

What it kills: E. coli actually is fairly sensitive to radiation, while salmonella and listeria require more energy. Although irradiation doesn't sterilize, the FDA ruled that food companies could use a dose proved to dramatically reduce levels of those germs, a dose somewhat lower than meat requires.

From wire reports