There are many news stories about wax on apples that cannot be washed off, and this wax is used to extend the fruit's shelf life. Some people use dish soap to wash fruit, and if it is not rinsed thoroughly with tap water, it can easily lead to a buildup of residue in the stomach, which is harmful to health over time. Washing apples with salt is a cleaner method.
When washing fruit, you can choose to use salt: wet the apple with water, put a little salt on its surface, then gently rub the apple back and forth with both hands. The surface dirt will be cleaned off quickly. Rinse it with water afterward, and it is safe to eat. The principle behind this cleaning method is that the granular state of salt increases friction, and salt is also harmless to the human body.
Washing apples with hot water is also a good method, as it easily removes preservatives and other substances from the apple's surface. Applying toothpaste to the apple's surface as a cleaner is also a good idea, and the fruit washed this way can be eaten without worry.