The claim that "the tars in cannabis are considerably more dangerous than those in tobacco" is made in Patricks An Introduction to Medicinal Chemistry (4th edition, p. 169). It's just a simple one line statement and not much attention is given to it, but from what I already knew this is to say the least a very controversial statement (see for example the independent website about drugs Erowid) and I expect better for a frequently used University level book.
The question is to what degree (from a chemical point of view) there is truth (or falsehood) to this statement given current more or less objective (not like the Heath monkey studies) knowledge? Is the author in his right to boldly state this?
