We've taken great pains in this space to warn you often about the many dirty foods you should avoid buying at your local grocery store or farmers market at all costs. No surprise, the most recent issue of Consumer Reports has fingered one of those risky foods: Leafy greens.

A surprising 39 percent out of more than 200 samples from 16 producers of packaged greens -- yep, those prewashed packages you count on to save time at the dinner table -- purchased in the Northeastern U.S. exceeded an unacceptable level of total coliforms, one indicator of poor fecal contamination used by industry experts. A second marker for contamination, enterococcus, was discovered in 23 percent of the samples tested.

Although bacteria counts varied greatly among products, even in the same brand, there were some uncomfortable similarities among samples with higher levels of contaminants:

1. There was no difference in cleanliness among organic and non-organic products, nor how they were sold at the grocery store (in plastic bags or containers).

2. More samples of spinach were tainted and were anywhere from 1-5 days away from their expiration dates.

3. At least one brand of packaged salad among the companies represented by more than four samples -- including national, regional and store brands -- tested positive for enterococcus or coliforms.

These results certainly explain why the Consumers Union supports the Food Safety Modernization Act that would allow the FDA to develop and enforce stronger produce standards.

Consumer Reports March 2010

Civil Eats February 2, 2010