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The clean 15 -

"The clean 15" ranks the fruits and vegetables lowest in pesticide residues, primarily based on USDA testing. To develop the list, the EWG reviews common, non-organic fruits and vegetables.

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Avocados -

When the USDA tested 360 avocados, less than 1% had pesticide residues. And of those with residues, only one type of pesticide was found. This makes this healthy, fatty fruit one of the least pesticide-contaminated produce items around.

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Sweet corn -

Less than 2% of sampled sweet corn, including corn on the cob and frozen kernels, had detectable pesticide residues.

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Pineapples -

When testing 360 pineapples, 90% had no detectable pesticide residues. This is thanks to their thick skin that provides a natural protective barrier.

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Onions -

Less than 10% of sampled onions had pesticide residues detected on them. They were analyzed after the outer layers of skin were removed.

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Papayas -

Some 80% of papayas tested had no detectable pesticide residues, based on analyzing the flesh, not the skin and seeds. The skin helps protect the flesh from pesticides.

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Asparagus -

About 90% of examined asparagus had no measurable pesticide residues. The vegetable contains an enzyme that may help break down certain pesticides.

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Cantaloupes -

Of 372 cantaloupes tested, over 60% had no detectable pesticide residues. Only 10% of those with residues had more than one type. The thick rind provides some protection against pesticides.

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Cabbages -

Around 86% of sampled cabbages had no detectable pesticide residues, and only 0.3% contained more than one kind of pesticide.

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Mushrooms -

Even when grown indoors, mushrooms can become infested with both bugs and disease. This is why, when tested, up to four pesticides were found. But surprisingly enough, they're still one of the vegetables with the lowest amount of pesticide residues.

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Mangos -

Nearly 80% of mangos were free from detectable pesticide residues. It was tested with the peel on after rinsing under tap water and draining.

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Sweet peas (frozen) -

About 80% of sampled frozen sweet peas had no detectable pesticide residues. However, snap peas, which are typically eaten whole, are higher in pesticide residues.

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Watermelon -

Thanks to its thick rind, the pink flesh of the watermelon is protected from pesticides. This makes it one of the fruits with the lowest traces of pesticide.

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Honeydew melons -

The thick rind of honeydew melon protects against pesticides. About 50% of the sampled fruit had no detectable pesticide residues. And those that did had no more than four different types.

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Sweet potatoes -

Sweet potatoes are known as one of the healthiest vegetables with few natural enemies. Therefore, they're one of the veggies with the lowest pesticide traces.

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Kiwis -

Some 65% of sampled kiwis had no measurable amounts of pesticide residues. Among those with detectable residues, up to six different pesticides were found.

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The dirty dozen -

According to the EWG, the following fruits and vegetables have the highest levels of pesticide residues. The list is called "the dirty dozen."

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Strawberries -

Strawberries are some of the most pesticide-filled fruits around. This is mainly because of the numerous species of insects and pathogens that attack them at several stages of their growth.

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Kale -

This leafy green has been found to have a high concentration of pesticides. Kale is susceptible to bugs laying their eggs among its curly leaves, as well as fungal attacks. Therefore, strong chemicals are used on non-organic kale.

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Celery -

Pesticide residues were found on over 95% of celery samples. Up to 13 different types of pesticides were detected.

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Peaches -

This fruit might look it has thick skin, but that doesn’t keep its luscious insides safe from a multitude of moths, beetles, and other pests. Due to this, peach farmers often need to spray the crop to achieve an edible product.

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Apples -

It takes a lot to produce picture-perfect apples. The beloved fruit is attacked by aphids, maggots, and many more pests. But luckily, some growers have adopted cultural control practices to reduce the need for pesticides.

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Spinach -

Spinach may contain pesticide residues that you can’t see. It's a cool weather crop that is often infested with insects like aphids, which can build up a tolerance to commonly used pesticides. This often forces growers to double up on chemicals to eliminate pests. So, even if you're buying pre-washed spinach, make sure to give the leaves a good soak.

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Tomatoes -

Four pesticide residues were found on the conventionally grown tomato. One sample contained over 15 different pesticide residues.

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Nectarines -

This delicate summer crop is at risk from insects, fungal infections, and nutrient deficiencies. To protect their trees, growers often spray protective solutions on the trunks and branches, which may reach into the fruit itself.

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Cherries -

Cherries are hard to manage because they're susceptible to many pathogens and insecticides. These are commonly used to kill pest species, but can also harm beneficial pollinators.

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Grapes -

Coined as "nature's candy," grapes have some of the highest amount of pesticide residues. Of the 122 chemicals found in samples, many have health impacts such as links to cancer, birth defects, developmental disorders, and respiratory system impairment.

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Bell peppers and hot peppers -

Most of the world’s peppers are produced in Asia. Botanically categorized as fruits, they're typically sprayed with pesticides to eliminate mites, leaf miners, weevils, and other insects.

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Pears -

Just like apples, pears attract numerous insects that crawl from the tree to damage the fruit. This forces growers to apply a high number of pesticides.

Sources: (CNN) (EWG) (Healthline) 

See also: Nutrition facts that should be common sense, but aren't  

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