Strawberries are one of the dirtiest produce in the U.S. The Environmental Working Group released its "Dirty dozen" list of fruits and veggies. Every since 2004, the group has released its Shopper's Guide to Pesticides in Produce, which ranks pesticide contamination of 47 popular fruits and vegetables

Spinach and kale are in second and third place. It doesn't mean people get an excuse to avoid fruits and veggies. The EWG says those are the items Americans need to eat more of. Washing fruit and vegetables is a good way to remove potential bacteria. Plain water is effective at removing most bacteria. 

The top "clean" foods are avocados, sweet corn and pineapples.