You definitely got my attention with “benzene derivatives” and “toluene”. How is it that benzene, a known and regulated carcinogen, can be used in FOs? Is it a concentration/exposure limit determination or due to the form of the benzene? Toluene may be safer, but I still think of it as a solvent that has undesirable side effects. I have only just begun doing any kind of research on fragrance chemicals. I’m not a chemist, which means there’s a very steep learning curve ahead. I found a website/forum called “basenotes” that seems useful. And, I apologize for further side tracking a mica thread!