Well, to begin, the potency and effect of marijuana is dependent on many factors. In fact, the temperature of the soil where it was grown and even the temperature of where it is stored and used can have an effect on its chemical composition. It can become more powerful(toxic) than Cocaine. The “harmless” joint can discreetly and easily be laced with other types of drugs, increasing the toxicity. Lastly, the slow seduction of its use, for some, can be more damaging than Cocaine.
Take it for what it is worth. I do not take my life, my brain and my body for granted, nor will I will be surprised to witness the influx of emergency visits and increased social despair that will happen with increased widespread use and acceptance.
Yes, you can poison pot. You can poison anything. This does not make pot toxic.