https://www.ewg.org/foodnews/dirty-dozen.php
Here is EWG’s list of the most contaminated produce — The Dirty Dozen (and most important to buy organic):
Strawberries
Spinach
Kale, Collard, & Mustard Greens
Nectarines
Apples
Grapes
Bell & Hot Peppers
Cherries
Peaches
Pears
Celery
Tomatoes
And here is their list of the least contaminated produce — The Clean Fifteen:
Avocados
Sweet Corn*
Pineapples
Onions
Papayas*
Sweet Peas, frozen
Asparagus
Honeydew Melon
Kiwi
Cabbage
Mushrooms
Cantaloupe
Mangoes
Watermelons
Sweet Potatoes
* A small amount of sweet corn and papaya sold in the United States is produced from bioengineered seeds. Buy organic varieties of these crops if you want to avoid genetically modified produce.
https://foodrevolution.org/blog/how-to-wash-vegetables-fruits/