I have a friend in the U.K. who is a retired medical doctor who worked for the U.K. anti-doping agency that deals with athletes. He told me that the reason MDMA got banned in the U.K. was that people were dying from a nasty condition called hyponatremia, which is very low salt levels in the blood. You can die from this condition, & people were dying from it at raves. Here is the article on this that I found: http://cjasn.asnjournals.org/content/3/6/1852.full
Jack
Jack