Dirty dozen list: Advocacy group releases annual list of produce with most, least pesticides

Strawberries, spinach and kale are among the dirtiest fruits and vegetables at supermarkets.

That's according to the annual "dirty dozen" and "clean fifteen" list from the Environmental Working Group -- a nonprofit advocacy organization.

When they say "dirty," they're talking about pesticides.

The report is based on data from the Department of Agriculture and the Food and Drug Administration, CNN reported.

They found that upwards of 90% of strawberry, apple, cherry, spinach, nectarine and grape samples had residues of at least two pesticides.

As for the most types of pesticides -- that ranking went to kale, collard and mustard greens, hot peppers and bell peppers.

Kale, for example, had as many as 21 different kinds of pesticides.

So what are the cleanest fruits and veggies?

Avocados, sweet corn and pineapple are at the top of the 'clean fifteen' list.