Russ,
Please take this as "debate", not "argument".
What makes walnut any safer than zebrawood? They are both plentiful in their native countries. Every wood species is native to SOMEONE. In many cultures, the export of wood COULD be a great source of revenue - kinda like we buy oil from many sources, but it all makes gasoline and heating oil.
My "point", if there is one, is that wood is wood. Some is more toxic, yes, but walnut is considered toxic by some standards, yet we make LOTS of table products from IT.
Honestly, I am not an expert, but I am always amused when the subject of wood peppermills changing the taste of PEPPER is introduced. Dried out wood, suitable for turning is extremely unlikely (IMO) to effect a pungent spice! MAYBE cocobolo could effect the taste of some subtle spices, if stored long enough, but PEPPER???????
Regarding the pieces (of deft) falling off - I would certainly bow to your opinion as I know you are better informed on wood finishing. I have, however, been continually using a peppermill I made nearly a decade ago. If I have ingested any deft, it would have been ground to tiny pieces and it must have been overcome by the pepper, or the salad I put the pepper on, as I don't have a recollection of "deft taste".
I welcome your further input, particularly as it might apply to the zebrawoods (and canarywoods) of the world, they do make attractive and saleable peppermills!![
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