According to a recently study by The Journal of Agriculture and Food Chemistry, scientists have found that out of 3 different washing techniques, a 1% baking soda water solution removed virtually all the chemicals and pesticides around on the exterior of Gala apples as well as removes some that have absorbed into the skin.
Scientists evaluated the effectiveness of a simple tap water rinse, a baking soda solution rinse, and a bleach solution rinse has on apples contaminated with chemical pesticides. Although a rigorous tap water rinse does remove some of the external pesticides found on the skin of Gala apples, a 1% baking soda/water solution works the best at removing these chemicals. After soaking the produce for 12-15 minutes they found it removed 80% of the thiabendazole and 96% of the phosmet. Of course this is quite a long time to wash produce every time you want to eat it, but even a brief wash with a baking soda solution has the potential to remove more chemicals than the average rinse under the faucet.