Removing Pesticides From Fruit

A common kitchen product could supercharge fruit-washing protocols. A new study, published in the Journal of Agricultural and Food Chemistry on Thursday, found that baking soda could remove far more pesticide from the surface of an apple than just tap water or a bleach rinse.

“Generally speaking in the U.S., the amount of pesticides on apples are well controlled,” said Lili He, a food scientist at the University of Massachusetts at Amherst and one of the authors of the paper. Scientists already knew that pesticides could be absorbed into fruits and that baking soda could remove them. However, no one had measured how deeply the pesticides had been absorbed. “We are the first ones to study how far it has penetrated and how hard it can be to wash away,” He said.

For their experiments, He and her colleagues picked up organic Gala apples from a local Stop and Shop and got two chemicals often used to treat fruits in the U.S. One, thiabendazole, kills fungus; the other, phosmet, kills insects. They applied the pesticides to the apples at the maximum level allowed by U.S. regulations. Then, they tried to get the pesticides off using tap water, bleach and a baking soda soak.