RE: Microballoons
I always heard microballons wer PVC balls. I know an old ARF I had came with PVC microballoons (used to strengthen CA.)
PVC is not good either, I remember the same safety warnings came with the old stuff.
I remember driving home with a small ziplock bag of white powder from the hobby shop. Had the thought if a cop pulled me over there would be a lot of explaining and little believing......