I agree with Don about fully cured finishes. Bob Flexner mentioned in a recent article in CabinetMaker/FDM that the whole "toxicity" issue has been 20 years of marketing for "food safe" finishes - which are nothing more than thinned-down versions of the same stuff ("Warning - contains petroleum distillates"). However, non-toxic when fully cured.

If you are really concerned, use mineral oil - a natural laxative, suitable for ingestion or shellac, which is what makes M&Ms "melt in your mouth and not in your hand". You may also be able to do some interesting things with food coloring as a stain under shellac.