These are the 12 most contaminated produce items from pesticides and other chemicals, opt for organic if you can:

Peaches
Apples
Sweet bell peppers
Celery
Nectarines
Berries, all, especially strawberries
Pears
Grapes
Spinach
Lettuce
Kale/collard greens
Potatoes

The “Clean Fifteen” lists the least contaminated produce items, ok to buy non-organic

Onion
Avocado
Sweet Corn (Frozen)
Pineapples
Mango
Asparagus
Sweet Peas (Frozen)
Kiwi Fruit
Bananas
Cabbage
Eggplant
Cantaloupe
Sweet potatoes
Grapefruit
Watermelon
Mushrooms