On Cannabis toxicity:
THC, the principal psychoactive constituent of the cannabis plant, has an extremely low toxicity. A 1998 study published in The Lancet reports: “There are no confirmed published cases worldwide of human deaths from cannabis poisoning, and the dose of THC required to produce 50% mortality in rodents is extremely high compared with other commonly used drugs”. Cannabis researcher Dr. Paul Hornby said that “you have to smoke something like 15,000 joints in 20 minutes to get a toxic amount of delta-9 tetrahydrocannibinol”. Recorded fatalities resulting from cannabis overdose in animals are generally only after intravenous injection of hashish oil.