Avocados – Fewer than 1% of avocados tested positive for pesticides. Best of all, only one pesticide of any kind was found on all the avocados tested. For these reasons, the Environmental Working Group ranked avocados as the No. 1 cleanest produce.
Sweet corn – Less than 2% of sweet corn, the second-cleanest produce, showed detectable levels of pesticides. Because a small portion of corn is grown from genetically modified seeds, the group suggests that those who wish to avoid genetically altered foods buy organic corn.