It really depends on how much you inject on wether or not it will kill you. It also depends on if you hit an artery or a vein, and how big it is. The reason that death can be brought in is due to the fact that when you inject Oil into your bloodstream it will crystalize forming a somewhat clogged drain type effect. Just like it does in a Pin if it sits too long(With some injects). Also, sometimes when you inject after you pull out there will be small amounts of blood that ooze from the puncture site, dont woryy about that. It only matters if you draw blood when you aspirate. And if you study it enough and know what you are doing, it should be no problem.