Hmm - note the word "inTOXICation". All substances that intoxicate are toxic to some degree. In fact, some poisonous mushrooms get you high before you die. So yes, marijuana is toxic - iow, considered as a poison by the body - to some degree. Obviously it won't kill a person. But it does kill some synapses, and the liver views it as a toxin that it must filter out and deal with. MJ also stresses the CNS (centeral nervous system) and it takes around 3 days for the THC to clean out (so you notice it, it can be detected in the body longer). In fact, after abstaining from MJ for around 10 years I smoked 3 hits - just THREE - and could feel the fuzzy, mentally dizzy, clouded, mode of darkness effect for three days. It certainly didn't tempt me to smoke any more.
So yes, it is toxic to some degree, as are all substances which intoxicate. But it's not lethal.
When I eat MSG I swell up like a balloon.