(CNN) - When someone coined the phrase "an apple a day keeps the doctor away," pesticides hadn't been invented yet.
According to the Environmental Working Group's annual "Dirty Dozen" report , the apple tops the list of the dirtiest produce you can buy.
The report names the fruits and vegetables ranking highest in pesticide residue.
It's based on data collected by the Department of Agriculture and the Food and Drug Administration.
The agencies tested samples as they normally would be eaten after being washed or peeled.
Celery earned the number two spot on the list.
The agencies also found pesticide in baby foods.
As for the cleanest produce, onions and sweet corn took the top spots.