Thanks everyone for the input. Gene, your comment is enough for me to not do it. It was convenient, but drawing at the time of injection does not take that much longer and hopefully using the small needles the vial stopper and vial sterility is not compromised. I found articles that suggest that BA could attack certain types of plastic / rubber.
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I make an effort to limit my exposure and intake of plastic leach by using glass or stainless steal for water bottles, food storage, purchased foods, coffee maker . . . I am not a fanatic, but try to reduced it compared to others by 80% or so. So much of the food is sitting in plastic for weeks or months. True for all chemicals I guess, just try to limit my contact/intake of chemicals and fumes. IMO, the human chemical exposure compared to 100 years ago is much greater when you think of all the chemicals in foods, lotions, medicine, water, and the air (inside and out). Again, not a fanatic, just make an effort when possible.