Pesticides in produce: Environmental Working Group's "Dirty dozen" list Pictures We've heard it all before: Load up on fruits and vegetables to boost your health. But pesticide residues have been tied to health risks, which is why the Environmental Working Group has reviewed USDA and FDA testing data to come up with its eighth annual "Dirty Dozen" list to let consumers know which foods are most commonly contaminated with pesticides. According to the group, the latest round of government tests found pesticide residues on 68 percent of food samples. Will one of these foods be in your dinner? Keep clicking to see which produce item earned the top spot on the Environmental Working Group's "Dirty Dozen" list.