Seems a bit silly to blend non bio with bio oil.
If you are going for bio degradable oil, there are recipes online and companies who sell premixed quarts. I did a bunch of research 15 years ago for my FMZ dishpan stationary engine which is now part of my garden tractor. It's a total loss lube system. So I didn't want non bio oil dripping in the garden. I have since installed an oil pan. The bio stuff I ordered works great.
Just googling I found this article:
http://discovermagazine.com/1998/aug/ediblemotoroil1466