Real Simple answers your questions.
Q. I can eat prewashed lettuce straight from the bag, right?
A. It’s safe, but you may want to give it a quick rinse anyway. The convenience of not washing greens is probably why you bought the bag in the first place, and it’s OK to toss them right into the bowl. “In my experience, contamination is much more likely to happen in your own home than in a factory,” says Jeff Nelkin, a registered dietitian and a food-safety coach in Woodland Hills, California. (Think bad habits like not washing your hands or cleaning the sink.) “Prewashed greens are treated with a mix of water and a food-grade sanitizing agent, like hydrogen peroxide or chlorine,” says Randy Worobo, an associate professor of food science at Cornell University. “This reduces and prevents the spread of bacteria from the produce surface.” The Environmental Protection Agency has determined that the amount of sanitizer residue remaining on produce poses no risk. And on organic greens, which meet the strictest standards, the amount is equivalent to (and often less than) what’s in your tap water. Still, if you can’t shake the thought of Balsamic-Chlorine Vinaigrette on your salad, go ahead and wash the lettuce in a clean bowl and spin dry.