median lethal dose

(redirected from LD 50)
Also found in: Thesaurus, Medical, Legal, Encyclopedia.
Related to LD 50: ED 50, LC50

median lethal dose


mean lethal dose

1. (Medicine) the amount of a drug or other substance that, when administered to a group of experimental animals, will kill 50 per cent of the group in a specified time
2. (Medicine) the amount of ionizing radiation that will kill 50 per cent of a population in a specified time
Abbreviation: LD50

me′dian le′thal dose′

the quantity of a lethal substance, as a poison or pathogen, or of ionizing radiation that will kill 50 percent of the organisms subjected to it in a specified time period. Symbol: LD50
References in periodicals archive ?
Data were evaluated by probit analysis (PoloPlus program) to determine the LD 50 (representing the dosage in mg/g insect that caused 50% mortality) along with 95% confidence intervals.
To determine the useful doses, two criteria are taken into account: the LD 50 and the stems and roots length reduction rate.
1-5) He also claimed that AFA was producing microcystin with an LD 50 of 50[micro]/kg.