Just in case you missed it, Consumer Reports came out with the results of a study on pre-washed bagged salad mixes. A high percentage of their sample, including the “organic brands,” was contaminated by bacteria and fecal matter. So, uh, wash that lettuce again, if you still want to buy it now. The magazine also suggests buying bagged salad as far from their use-by dates as you can find.
Bagged salad: How clean? (Consumer Reports)