If you buy organic for only a handful of fruits, do it for apples, blueberries, grapes and strawberries. According to the nonprofit advocacy organization the Environmental Working Group, it found 98 percent of the apples tested contained detectable levels of pesticides. Conventionally grown blueberries had more than 42 types of pesticide residue on them. Grapes tested for the highest amount of pesticides, with more than 64 types in the testing. And in just one strawberry, it found a whopping 13 pesticides. Since many fruits are like sponges that absorb whatever is sprayed on them, even washing most of these fruits can still lead to the ingestion of chemicals. Go organic with these if you can.