So take home message is that there is still so much that is unknown and we really need more research on the effects these compounds have on the body.

MAOIs are clearly the highest risk for toxicity and any complete assessment of the toxicity of oral preparations shouldn't ignore this. The author acknowledges this short-fall however.

The DMT seems to be the high-risk compound pcychologically speaking and the overwhelming message is that of a lack of information. I seriously doubt the UDV assessed its members for and diagnosed incidences of "psychosis" with the rigour that strict clinical psychology would probably demand for publication. This is why it is of utmost importance that psychonauts report all negative psychological effects possibly linked to these substances as this is the only "data" being collected world-wide.