: According to some experts, the symptoms of poisoning are identical to those of a dose of 2 GBq (50 millicuries), the activity of 10 millionths of a gram of polonium 210. This dose is over 200 times the amount required to leave a 50% chance of survival. The cost of polonium, estimated at 25 million dollars per kilogram by the Berliner Zeitung, fortunately minimises the risks posed by such techniques. For secret agencies, this method of assassination is highly visible and less effective than the classic Bulgarian umbrella dipped in cyanide