There is no scientific evidence for what this article claims either. The entire piece is a disgrace. Yes, avoid eating soap, but don't accept any non-scientific drivel about how impossible it is to get from food/surfaces.
A commenter on the article makes a good point: "If washing vegetables with soap can get you sick, why use soap to clean dishes, glasses, and utensils? Just use water only. Right??"
Drinking dishsoap can give you an upset stomach so you shouldn't wash produce with it? Is this guy retarded?