[rlearp]

Guys, I'm a chemist (not that means much) and Zylene and Toluene are nothing to worry about (within reason). You handle gasoline on a daily basis, yes? Well, you already handle materials with about the same MSDS (Material Data Safety Sheet) as the things you are worried about. Just don't get it in your eye, don't soak your hands in it, and don't breathe in the fumes.

To get it cheaply contact Fisher or VWR, that is what I do and I get it by the case of 4-4L bottles. Don't get anything that is setup for HPLC, UV-vis spectroscopy, or is marked analytical grade. This stuff is for lab research and will cost you much more than needed. You want the cheapest stuff they sell. To avoid shipping charges find the stockroom at your local University campus or find a chemical supplier in your town, they should be able to help. It'll be a lot cheap than any additives you purchase and will work just as good.

Ron