Acetonitrile is used on an almost daily basis by anyone doing HPLC (high-performance liquid chromatography). Big 4L jugs of it. The price has gotten exorbitant though and some have switched to using mostly methanol. I don't know what this guy is talking about with the toxicity, it smells kind of nice and has a very benign label. You don't even need to wear a respirator or anything to use it.