Someone on the April DDC had said the one their midwife offered had aluminum in it. That's why I figured they all did. So, yeah, I would definitely check on what ingredients are in there at the very least. I have heard that the amount of Vitamin K given whether orally or through the shot is in excess of what baby needs typically and could be damaging for that reason. So, I'd definitely recommend at least looking into that more.
Oh, and don't just take their word for it as the woman in the April DDC's midwife said it was based in something else and she only found out it was in aluminum when she asked to look at it and read the label.