Inexpensive high

Actually there is a subtle irony in the title. Some weeks ago I read that ninety nine percent of english bank notes had traces of cocaine on them. This morning yet another report that one hundred percent of irish euros had cocaine one them also. So exactly how many notes would one need to lick to get high on the stuff? Indeed who would be so desperate enough to lick said notes knowing that a part of it had been up some ones nose? A sticky problem but not one to be sniffed at...