You do not need to wash bagged salad greens labeled pre-washed or ready-to-eat. The FDA says that if the package states it, you can use the produce without washing it again. If you choose to rinse it anyway, the agency says to make sure it does not touch unclean surfaces or utensils, which helps avoid cross contamination.

Safety starts at the store. The FDA says to choose pre-cut, bagged or packaged produce, such as bagged salad greens, only when it is refrigerated or surrounded by ice. Bag fresh fruits and vegetables separately from raw meat, poultry and seafood on the way home, and refrigerate all produce bought pre-cut or packaged.

At home, the agency says to keep perishable produce like lettuce in a clean refrigerator at 40° F or below, and to use a refrigerator thermometer to check. Keep produce that will be eaten raw away from raw meat, poultry and seafood, and from the utensils used for those foods.

For produce that does need washing, the FDA says to begin with clean hands, washed for at least 20 seconds with soap and warm water, and to rinse under running water. Soap, detergent and commercial produce washes are not recommended. Washing reduces bacteria but does not eliminate it, the agency says, and drying with a clean towel helps further.