Casting metal powders in acrylics and oils

Hi,
I have been interested in the possibility of mixing metal powders such as bronze, copper, brass and stainless steel powders in a linseed oil& gamsol medium, as well as in an acrylic medium. I am imagining that all these metals will dull over time, but I am curious about the integrity of the paint film and also wonder about the toxicity risk once the pigments are integrated in a paint body. Are they only dangerous when airborne or is mixing them likely to set a hazardous reaction?
Are there certain metal powders that you would recommend that are less likely to dull and darken ? I am dreaming of mixing paints that are genuinly made of metal powders that would look like a rough Richard Serra surface, but painted. I find the ‘metallic paints” sold by companies like williamsburg annoying as they are often mixed with mica or other irridescent components that feel too gimmicky or illusionistic. I would like to use metal powders as a more raw and direct application of these materials.
Lastly,  if I do an underpainting with metal powders, is it risky to layer oil colors from tubes on top?
I hope this post starts an interesting conversation on the possibility of grinding metal powders in oil and acrylic paint bodies. 
​thank you, I am such a fan of this platform!
Alex
For reference, here’s a link to the specific brand of casting metal powder I am talking about / have tried to experiment with :  https://www.dickblick.com/items/artmolds-powders-12-lb-bronze/