Apples are treated with various chemicals, including diphenylamine, which may promote the formation of nitrosamines, a class of chemicals linked to cancer. The Harvard T.H. Chan School of Public Health recommends washing apples with water and baking soda to remove pesticide residues, but this step alone may not be enough to eliminate all the chemicals.

Researchers applied the insecticide phosmet to organic apples and washed them with sodium bicarbonate, finding that while they had fewer pesticide residues, some were still left in their peels. While there are no studies to support the use of baking soda for removing diphenylamine, the compound can break down most pesticides, allowing you to rinse them off more easily.

Washing apples with baking soda can only remove the pesticide residues on their skin, so if the chemicals have already penetrated the peel, you must go one step further to get rid of them. Your best bet is to peel the fruits and then rinse them again, although some pesticides can penetrate their flesh and you’ll miss out on the nutrients apple skin provides.