I know it feels like summer has only just begun, but fall is right around the corner -- and that means apple season is almost here.

Don't be fooled by the apples you'll find in the supermarket year 'round -- most of them are actually months old... and you won't believe the tricks they use to keep them fresh.

The guy in the produce department will tell you that the secret is cold storage -- but those apples aren't just placed in a giant fridge somewhere.

They're also given a massive dose of pesticides after they're harvested in order to prevent mold, blight, rot, and stains during that storage period.

They're pumped so full of chemicals that a recent study based on government data found at least two pesticides on 92 percent of all apple samples even after they were washed and peeled.

And 98 percent of more than 700 apple samples tested by the USDA had at least one pesticide.

As a result, apples were placed on top of the Environmental Working Group's "dirty dozen," a list of fruits and vegetables that contain the highest levels of pesticides.

EWG says apples are followed by celery, strawberries, peaches, spinach, imported nectarines, imported grapes, sweet bell peppers, potatoes, domestic blueberries, lettuce, and kale.

If you can't afford to buy everything organic – and these days, who can? -- make sure you at least go organic for those.

While there's not a lot of research on what a low-but-steady stream of pesticides can do to a person, we do know that higher doses can cause cancer and hormonal problems.

Some studies have found that farm workers exposed to pesticides on the job have a higher risk of Parkinson's disease. And in pregnant women and children, pesticide exposure has been linked to low birth weight, brain damage, ADHD, and even lower intelligence later in life.

But the news from the produce aisle isn't all bad. EWG also found a number of fruits and vegetables so low in pesticides that you don't have to buy organic.

They call them the Clean 15: onions, corn, pineapples, avocado, asparagus, sweet peas, mangoes, eggplant, domestic cantaloupe, kiwi, cabbage, watermelon, sweet potatoes, grapefruit, and mushrooms.

The organization has a helpful guide you can print, clip and bring to the supermarket.

It's just about the only time you might need to compare apples and grapefruit.