Fruits and vegetables with edible skin
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Fruits and veggies with an edible skin or no skin at all are the most contaminated. The worst, or "Dirty Dozen," according to the Environmental Working Group, are apples, celery, strawberries, peaches, spinach, nectarines, grapes, bell peppers, potatoes, blueberries, lettuce, and kale/collard greens. When available, buy these organic.