"Windthrown, I am sorry about your Dad."
I will second that...i know the drill: lost my dad to colon cancer, mom to ovarian cancer...it really sucks.
Whenever I use anything with 6-chain carbons or more, as well as cutting CCA and like lumber, I take the necessary precautions. I do believe the more you are around and handle materials like this, it is empirical your odds not too your advantage. I think you summed it up Windthrown when you stated your father "taste-tested" those chemicals...that would be tough for anyone to beat.
For me, I do use hudraulic fluids to my advantage, which is a preventative to keeping termites from engulfing the base-boards on all my sheds....the old post-WWII farmer used to use chlordane to protect his sheds, but we know what the EW's did to stop this...however, I do use brand-new fluids in all my combustion-based machines and will continue to do so.
Hope you have a good & safe week.
tstex