Hi Anicca, I have some experience. First I should say that I vape my enhanced leaf, and don't smoke/burn it. This might be significant because I am not dealing with the byproducts of combustion, some of which might well be toxic... Obviously, many herbs have been used for smoking down the years, so that's a good list to start from. Woods, on the other hand, such as cedar and palo santo, have not generally been used in smoking blends as far as I am aware, so more caution is advised there. Palo Santo (as incense) in particular is known for intensifying purges, so I'd be very careful about inhaling that in any quantity...!
The shortest, safest answer is to start with food-grade, organic, wild-crafted oils from edible things. I add one drop each lemon and chamomile-Roman oils to my blend just before I vape it, and that's plenty, and very pleasant.
These oils can be expensive! If you see a range where all the oils are priced at $1.99, irrespective of source, AVOID, as they're most likely synthetic.
Here's
a list of oils to be avoided, there are many versions of such lists around.
Be aware that some oils can also exert potent effects on enzymes, not so much MAO, but CYP450, which is complex and can definitely interact with many other substances you might consider co-ingesting...
Good luck.
“I sometimes marvel at how far I’ve come - blissful, even, in the knowledge that I am slowly becoming a well-evolved human being - only to have the illusion shattered by an episode of bad behaviour that contradicts the new and reinforces the old. At these junctures of self-reflection, I ask the question: “are all my years of hard work unraveling before my eyes, or am I just having an episode?” For the sake of personal growth and the pursuit of equanimity, I choose the latter and accept that, on this journey of evolution, I may not encounter just one bad day, but a group of many.”
― B.G. Bowers
ॐ