Washington ? Consumers worried about salad safety may soon be able to buy fresh spinach and iceberg lettuce zapped with enough radiation to kill E. coli and other germs.

The Food and Drug Administration will issue a regulation today allowing spinach and lettuce sellers to take that step, a long-awaited move amid increasing outbreaks from raw produce.

It doesn’t excuse dirty produce, warned Dr. Laura Tarantino, FDA’s chief of food additive safety. Farms and processors still must follow standard rules to keep the greens as clean as possible – and consumers, too, should wash the leaves before eating.

Irradiated meat has been around for years. Spices also can be irradiated. But the Grocery Manufacturers Association had petitioned to allow irradiation of fresh produce, starting with leafy greens that have sparked numerous recent outbreaks, including E. coli in spinach that in 2006 killed three people and sickened nearly 200.

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 Company confirmed it is considering irradiated lettuce.

A leading food safety expert said irradiation indeed can kill certain bacteria safely – but it doesn’t kill viruses that also increasingly contaminate produce.

“It won’t control all hazards on these products,” cautioned Caroline Smith DeWaal of the Center for Science in the Public Interest.

She questioned why the FDA hasn’t addressed her agency’s 2006 call to require growers to document such things as how they use manure and ensure the safety of irrigation water. Irrigation is one suspect in this summer’s nationwide salmonella outbreak attributed first to tomatoes and then to Mexican hot peppers.