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Dirty Dozen - Shoppers' Guide To Pesticides in Produce

Dirty Dozen

Environmental Working Group’s (EGW) 2018 “Dirty Dozen” list - the most heavily pesticide & herbicide-sprayed non-organic produce on the market. Almost 70% of non-organic samples tested positive for at least one pesticide, many are banned in other countries. But these are the foods I make sure to buy organic.

Each of these foods tested positive for a number of different pesticide residues and contained higher concentrations of pesticides than other produce.

1. Strawberries

One strawberry sample contained an astounding 22 pesticide residues.

One-third of all conventional strawberry samples contained 10 or more pesticides.

2. Spinach

97 percent of conventional spinach samples contained pesticide residues.

Conventional spinach had relatively high concentrations of permethrin, a neurotoxic insecticide.

3. Nectarines

Nearly 94 percent of nectarine samples contained two or more pesticides.

One sample of conventionally grown nectarines contained residues of 15 pesticides.

4. Apples

90 percent of conventional apples had detectable pesticide residues.

80 percent of apples tested contained diphenylamine, a pesticide banned in Europe.

5. Grapes

Grapes contain an average of five pesticide residues.

More than 96 percent of conventional grapes test positive for pesticide residues.

6. Peaches

More than 99 percent of conventional peaches had detectable pesticide residues.

An average of four pesticide residues were detected on conventional peaches.

7. Cherries

An average of five pesticides were detected on conventional cherries.

30 percent of cherry samples contained iprodione, a pesticide not allowed in Europe, which may cause cancer.

8. Pears

Pears contained several pesticides in relatively high concentrations, including insecticides and fungicides.

More than half of conventionally grown pears tested had residues of five or more pesticides.

9. Tomatoes

Nearly four pesticides were detected on the average conventionally grown tomato.

One sample of conventional tomatoes contained 15 different pesticides and breakdown products.

10. Celery

More than 95 percent of conventional celery samples tested positive for pesticides.

A maximum of 13 pesticides were detected on a sample of conventional celery.

12. Potatoes

Conventional potatoes had more pesticide residues by weight than any other crop.

One pesticide in particular, chlorpropham, makes up the bulk of pesticides detected on potatoes.

11. Sweet Bell Peppers

Almost 90 percent of conventional sweet bell pepper samples contained pesticide residues.

Sweet bell peppers can contain fewer pesticide residues than other Dirty Dozen foods, but the pesticides tend to be more toxic to human health.

Key findings:

More than 98 percent of samples of strawberries, spinach, peaches, nectarines, cherries and apples tested positive for residue of at least one pesticide.A single sample of strawberries showed 20 different pesticides. Spinach samples had, on average, 1.8 times as much pesticide residue by weight than any other crop.

How Consumers Can Avoid Pesticides?

People who eat organic produce eat fewer pesticides. A 2015 study by scientists at the University of Washington found that people who report they often or always buy organic produce had significantly lower quantities of organophosphate insecticides in their urine samples. This was true even though they reported eating 70 percent more servings of fruits and vegetables per day than adults who reported they rarely or never purchase organic produce.

The fertility studies demonstrate potentially subtle but important impacts of eating lower-pesticide-residue produce. These studies define low- and high-residue foods in a method similar to EWG’s guide. They utilise the same data source, the USDA’s Pesticide Data Program, and create a crop-level residue index that largely overlap with EWG’s Dirty Dozen and Clean Fifteen lists. The researchers found that people’s self-reported dietary habits correspond to pesticide measurements in their bodies. Male EARTH study participants who reported the highest consumption of high-residue crops had higher concentrations of organophosphate and pyrethroid insecticides, and the herbicide 2,4-D in their urine relative to participants who eat these foods less often.

The Shopper's Guide is not built on a complex assessment of pesticide risks but instead reflects the overall pesticide loads of common fruits and vegetables. This approach best captures the uncertainties about the risks and consequences of pesticide exposure. Since researchers are constantly developing new insights into how pesticides act on living organisms, no one can say that concentrations of pesticides assumed to be safe today are, in fact, harmless.

The Shopper's Guide aims to give consumers the confidence that by following EWG's advice, they can buy foods with fewer types of pesticides and lower overall concentrations of pesticide residues.

This article was adapted and updated from the EGW Shopper's Guide 2018..

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  9. California Department of Pesticide Regulation, Pesticide Residues on Fresh Produce. 2015. Available at

  10. EWG's 2018 Shopper's Guide to Pesticides in Produce™. Available at



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