DMPS & DMSO chelation therapy.

My daughter and I had this chelation therapy a couple of years ago. I had had a dental cleanup done, and the chelation was highly recommended by my doctor at the time. He also told me that my daughter would have injested mercury and cadmium through breastfeeding,(I had been tested for these substances and came up pos for both in blood & hair). After this therapy, of which I had about 5 times, I started to put on weight at a rather rapid rate, no change to my diet at all. I adhere to a mostly fresh food healthy diet, limited junk.
Anyway, now I research the net and find that chelation therapy is supposedly very bad for the liver & kidneys. This doctor never told me that, he only raved about it.
Could this therapy have damaged the liver & kidneys of my daughter and I? We both seem to have had mild liver/kidney related problems since. My daughter was only 6 when given this therapy. I am horrified at the thought that I trusted my health to him, if this therapy is dangerous.
Elizabeth.