TD50 is a toxicology term that relates to the median toxic dose of a substance in which toxicity occurs in 50% of a species. It is, therefore a measure of carcinogenic potency. It provides a standardized, quantitative measure that can be used for comparing and analyzing carcinogens. It is the dose required to get 50% of a population reporting a specific toxic effect.
Safeopedia Explains TD50
The TD50 is also referred to as the threshold dose or median toxic dose. It is expressed in milligrams per kilogram of bodyweight per day. The TD50 would induce tumors in half the number of test animals at the completion of the standard lifespan for a species.