WASHINGTON — Danger could be hiding in your dinner salad.

Food most people consider healthy, such as raw sprouts, salad greens, cooked fruit and rice, can pose serious health risks if they are improperly prepared and stored.

Sprouts are considered risky because they grow in a bacteria-friendly moist environment. Outbreaks have involved raw alfalfa and mixed sprouts that were contaminated with salmonella, which can lead to fever, cramps, diarrhea and even death, according to the Food and Drug Administration. Thorough cooking significantly reduces health risks for sprouts and other foods.

Certain people are at greater risk, including young children, the elderly, immune-compromised, and pregnant women, according to Sam Beattie, a food safety extension specialist at Iowa State University.

The bacteria campylobacter, salmonella and E. coli, as well as Norwalk and Norwalk-like viruses cause the most commonly recognized food-borne infections, according to the Centers for Disease Control and Prevention. The CDC is working on analyses to estimate the number of illnesses each year in the U.S. from various foods. Initial reports are expected in 2008.

Well-documented sources of contamination are undercooked and raw meat and poultry, raw eggs, unpasteurized milk, and raw shellfish, according to the CDC. But eaters may be less familiar with threats posed by improperly cooked or stored fruits and vegetables. Produce can be contaminated at home, or on the farm, by unclean water and by manure used for fertilization, according to the CDC. Washing produce reduces risk, but doesn't eliminate contamination.

Eaters should also be wary of prepared items such as burritos. First, ingredients for burritos — cooked chicken, beef, beans, rice, and lettuce — are frequently held at improper temperatures, thereby allowing certain types of bacteria to proliferate.

Second — here comes the "ick" factor — the more your burrito, or any other prepared food, is handled, the greater the chance of human fecal contamination, according to Iowa State's Beattie.

Eaters should also be wary of cooked food that has been sitting out at the barbecue or picnic for several hours. Experts recommend leaving that leftover potato salad alone. Better yet, throw it away. If rice, pasta or stew has been hanging around for a few hours, you may be better off going hungry than loading your plate.

Just a year ago, at least three people died and hundreds were sickened in an E. coli outbreak traced to raw spinach that was grown in California and had been contaminated by cattle feces. Dr. Rajal Mody, a medical epidemiologist with the CDC, said unpasteurized fruit juices, especially apple cider and juice, have been linked to contaminants such as E. coli and salmonella. Consumers should watch out for unpasteurized juice offerings at roadside stands, even if the juice is from a local farm. There has been an increase in food-contamination outbreaks related to fresh produce in recent years, Mody said.

"The problem with unpasteurized ciders (and juice), especially when apples are picked off the ground, is that the apples that are lying on the ground are going to come into contact with soil, and potentially any animal that is walking by could leave droppings," he said.

The produce items that have been the most frequent culprit foods have been leafy green vegetables, tomatoes and melons, Mody said. "We still are unsure why these items are popping up in food-borne outbreaks. We think it has something to do with the farm field itself, but definitely more research is needed to figure out the routes of contamination," he said.

Consumers also need to be wary of cooking vegetables and fruits using recipes that add enough moisture to transform the food into a potential bacteria breeding ground.

For example, dry beans are not considered a risky food. But cooking the beans can add enough moisture to create a contaminant-friendly environment.