UC Davis Cooperative Extension specialist Trevor Suslow wrote an opinion piece for Food Safety News saying a recent Consumers Union study - which questioned the safety of prewashed salad greens - has caused a flurry of concern and confusion.

An article in the March 2010 issue of Consumer Reports magazine said its study of packaged leafy greens found nearly 40 percent of samples contained bacteria that are common indicators of poor sanitation and fecal contamination, according to a news release distributed on PR Newswire.

Suslow wrote that he thinks it is "grossly unfair" to raise fears beyond what is supported by science and everyday shared experiences with salad greens.

"What I rely on for my personal confidence in regularly consuming lettuces, spring mix, and spinach salads is that there are billions and billions of servings of these items consumed every year in the U.S. alone and the predominant experience we have is of safe consumption," Suslow wrote.

The CR news release said FDA should increase the specificity of its guidance and regulations for packaged leafy greens. In the meantime, the writers suggested consumers buy packages as long as possible before their use-by date and wash the greens at home, even if the packages say "prewashed" or "triplewashed."

Suslow agrees customers should look for use-by dates on packaged leafy greens. He goes further to suggest consumers note that packages in grocery stores are refrigerated vertical in a row, not laid one on top of the other in stacks.

Suslow said he checks the temperature of the greens' display case with his hand and confirms that the bags are very cool to the touch. (Perhaps one day there will be a cell phone ap for that, Suslow suggests.)

But he doesn't recommend consumers wash packaged salads at home.

"I do not support or believe that re-washing packaged salads should be a recommendation for the home consumer," Suslow wrote. "A large and diverse panel of experts published a comprehensive article in 2007 detailing the scientific evidence for the lack of benefit and the greater risk of cross-contamination in the home."