High Quality Content by WIKIPEDIA articles! In toxicology, the median lethal dose, LD50 (abbreviation for “Lethal Dose, 50%”), LC50 (Lethal Concentration, 50%) or LCt50 (Lethal Concentration & Time) of a toxic substance or radiation is the dose required to kill half the members of a tested population after a specified test duration. LD50 figures are frequently used as a general indicator of a substance's acute toxicity. The test was created by J.W. Trevan in 1927. It is being phased out in some jurisdictions in favor of tests such as the Fixed Dose Procedure; however the concept, and calculation of the median lethal dose for comparison purposes, is still widely used. As a measure of toxicity, LD50 is somewhat unreliable and results may vary greatly between testing facilities due to factors such as the genetic characteristics of the sample population, animal species tested, environmental factors and mode of administration. Another weakness is that it measures acute toxicity only (as opposed to chronic toxicity at lower doses), and does not take into account toxic effects that do not result in death but are nonetheless serious (e.g. brain damage).

Данное издание не является оригинальным. Книга печатается по технологии принт-он-деманд после получения заказа.