An apple a day keeps the doctor away… until the pesticides get you.

According to the Environmental Working Group, “Apples tend to have the most pesticides because of the chemicals applied to the crop before and after harvest to preserve them longer.”

A study by study author Lili He, Ph.D. at UMass Amherst tested apple-washing methods, the National Post reports.

The best way to get pesticides off apples is to soak them for 15 minutes in a baking soda solution—one teaspoon per two cups of water.

Soaking the fruit for two minutes gets most of the pesticides off, but 12–15 minutes is best. Then, rinse the apples with clean water and enjoy.