A toxic dose level is used by toxicologists, pharmacologists, and other scientists to figure out the safety of certain drugs, substances and chemicals. In toxicology, the median lethal dose or LD50 is the measurement of the lethal dose of the substances required to kill half the members of a tested population during a specific duration. The lower the LD50 the more toxic a substance, pathogen or chemical is. The LD50 is typically found by tests on animals like mice. This chart put together by a team at CEUfast a site for continuing nursing education, shows the median lethal dose of the following 55 substances.
Among these items are substances with very high LD50 numbers (meaning they are less toxic) like water, sugar, salt, milk, vitamin C and caffeine. The top five most toxic substances on this list are as follows: Polonium-210 which can be found in nuclear weapons, Diphtheria Toxin which is thankfully easily preventable by a vaccine today, Shiga Toxin from the illness dysentery, Tetanospasmin, the toxin that causes tetanus and finally the most toxic on the list, Botulinum Toxin which causes botulism and is used in Botox.