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I inject once a week in my quads (area 1 in the gif below), and I understand that aspirating is considered a necessary precaution?  Some sources say it is, other sources seem to deem it unnecessary.  Isn't it dangerous to accidentally inject into the bloodstream?  And if one accidentally does, does he lose all the benefits of that week's injection?  What are the chances of the T entering the bloodstream if one never bothers to aspirate?