by Ruth Ann Clayton, RD

Each spring the Environmental Working Group (EWG) publishes a list of twelve types of produce that are shown to contain the highest amount of pesticide contamination. The resulting group is known as the “Dirty Dozen”.

The list is generated from recent Food and Drug Administration and United States Department of Agriculture testing of pesticides found in conventionally grown, (not organic) produce. The Dirty Dozen changes annually as the amount of pesticides used varies each year. The 2017 list contains produce that are consistent in their levels of pesticide residues and reflects last year’s harvest.

Fruits and vegetables, as we know, are full of nutrients and fiber. You see the beautiful red of an apple, the green of spinach or the purple of grapes. What you cannot see is the pesticide residue, which remains on food after it is applied to crops in the fields or later as a preservative. If you eat it you are exposed.

Pesticides are toxins that have an accumulative effect and cannot be any better for you than they are for the weeds and insects they are trying to harm. Just how bad they are can be debated but it is known that many pesticides are neurotoxins and linked to nervous system disruption, cancer risk, birth defects, developmental problems in children and other chronic diseases. Children are especially susceptible to damage from pesticides. Can there be a “safe” level of such toxins?

The trick is in the knowing. Would you eat a food you knew to be contaminated with pesticide residue? Would you eat produce if it was labeled to contain neonicotinoid pesticides, suspected neurotoxins, or diphenylamine (DPA ) a fungicide used on apples which has been banned by the European Commission?

Leafy greens, fruits from trees, berries and grapes almost always make the annual list. The 2017 “Dirty Dozen” list of conventionally grown produce containing multiple pesticides in descending order is strawberries, spinach, nectarines, apples, peaches, pears, cherries, grapes, celery, tomatoes, sweet bell peppers, and potatoes. Kale, collard greens and hot peppers were also found to be frequently contaminated. Some of this conventional produce is made into products such as juice and baby food.

Riding to the rescue is the “Clean Fifteen” showing zero to no more than four types of pesticides. The “Clean Fifteen” include avocados, sweet corn, pineapple, cabbage, sweet peas, onions, asparagus, mangoes, honeydew, papaya, kiwi, eggplant, grapefruit, cantaloupe, and cauliflower. It is no coincidence that thick skinned produce appears to have the least amount of residue. Produce was tested as it would traditionally be eaten with thick skins removed.

To avoid pesticides growing your own produce is an option but not practical for everyone. Thoroughly washing and scrubbing produce may remove some of the residue. Exposure can also be minimized by peeling fruits and vegetable before eating. However grapes, strawberries and other items are difficult to peel and have absorbed the residues.

These lists are meant as an alert and not meant to discourage the eating of produce. The best way to lower the exposure to these pesticide residues is to purchase certified organic produce which, by USDA standards, cannot contain pesticides. Buying only certified organic produce is ideal but not always possible. You can, however, go a long way toward reducing pesticides in your body by using the EWG’s annual “Dirty Dozen” list to help make informed choices about which certified organic produce you should consider. The EWG estimates you could significantly reduce your pesticide consumption by switching to certified organic for the items on their list.

Should you take a chance with the health of you and your family? There is a growing body of knowledge that even small doses of pesticides can adversely affect your health. But please remember it is better to eat the conventional produce on this list than to avoid it all together. You need the nutrients.

There is a bit of good news. Some of the local growers on our own Farmer’s Market are very clean producers and are happy to discuss their processes with you. So, it is your awareness that becomes important in these days of heavy pesticide use. The “Dirty Dozen” and the “Clean Fifteen” are there to help you decide for yourself how you will purchase produce and the questions you should ask.

For more information and a Shoppers’ Guide to Pesticides in Produce, check out the complete report and lists at

Ruth Ann Clayton is the Registered Dietitian at Nature’s Way. Reach her at This information is not intended to diagnose, treat, or cure any disease.


Ruth Ann Clayton, Registered Dietitian, is active in both the American Dietetics Association and Dietitians in Integrative and Functional Medicine Dietetic Practice Group. Her nationally accredited Dietetic Internship and her years of experience in public health and hospital settings reflect her commitment to your health and well being.

As the co-owner of Nature’s Way, she uses her comprehensive background to research products, read labels, investigate manufacturers and provide information for her customers.