Produce that you should buy organic (fruits and vegetables with high pesticide levels):

Apples
Bell Peppers
Celery
Cherries
Grapes (imported)
Nectarines
Peaches
Pears
Potatoes
Red Raspberries
Spinach
Strawberries

The following are the lowest in pesticides:

Asparagus
Avocados
Bananas
Broccoli
Cauliflower
Corn (sweet)
Kiwi
Mangos
Onions
Papaya
Pineapples
Peas (sweet)

The produce ranking was developed by analysts at the not-for-profit Environmental Working Group (EWG) based on the results of more than 100,000 tests for pesticides on produce
collected by the U.S. Department of Agriculture and the U.S. Food and Administration between 1992 and 2001. The description of criteria used in developing the rankings is available at www.foodnews.org.