Hi. I thought the same thing this is incredible when to a ND for some other work... I had seen this treatment being done by someone else so I said what the heck I will give it a try. I didn't see the first part with the metal coming off the plates which I did see when my feet were in the tub.
He had some plastic blood collection tubes so I took some samples of the water to be tested and under microscope. The results came back as no bodily fluids but just metals from the plates.
The TV show 20/20 also did a special on those Japanese foot pads you put on your feet over night and test like 20 people. They tested the pads in the lab and found no toxins being emitted into the food pads.
I would stick to an infrared sauna and sweat the toxins out of the body.