The name LD50 is an abbreviation for “Lethal Dose, 50%” or median lethal dose. It is the amount of the substance required (usually per body weight) to kill 50% of the test population.
The test was created by J.W. Trevan in 1927, but has been phased out. The U.S. Food and Drug Administration has begun to approve non-animal alternatives to LD50, in response to research cruelty concerns and the lack of validity/sensitivity of animal tests as they relate to humans.
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