Unless you're trying to teach a lesson to a foul-mouthed youngster, soap generally isn't meant to be consumed. In fact, some researchers believe that residues left behind on soaped-up fruits and vegetables might be as harmful as any chemical residues you're trying to avoid. So, no, generally, soap isn't recommended to be used on any food. However, a good, thorough rinsing under cold, running water is always recommended for fresh fruits and vegetables. Not only will it wash away many chemical residues, but it will rid your food of some microbial contaminants, too.
Most scientists say that's even more important.
The minuscule amounts of pesticide residues on fruits and vegetables are generally thought to be much less of a health threat than bacteria and other microorganisms that can be on the surface of our favorite fresh snacks. Because of that, it's important to rinse off even produce that's been grown organically. Any food can be subject to microbial attack. A few years ago, some manufacturers came out with special rinsing agents for fruits and vegetables. Again, most nutritionists and food scientists say they are unnecessary.