A 2010 study from Consumer Reports found that nearly 40 percent of pre-washed salads sold in plastic bags or so-called plastic clamshells may be contaminated with bacteria that could be harmful to your health. They did a small study, just over 200 samples, and they found that 39 percent of those samples contained a family of bacteria known as coliform, which is a general indicator for contamination. Twenty-three percent of them contained a bacteria known as enterococcus, which is usually associated with fecal contamination. Not what you want to hear in your produce. It's not sterilized, it's just pre-washed. But there weren't other bacteria found in the study that we tend to associate with foodstuffs. It's important to note they did not find E.coli, they did not find salmonella, but they actually found the worst contamination in package containing spinach. We've heard a lot about spinach in the past. Spinach was a big offender and especially those packa...