Median lethal dose is the amount of a lethal substance that will kill 50% of a target population over a set period of time. Median lethal dose relates to substances including poisons, pathogens and ionizing radiation. Median lethal dose is often abbreviated as DL50.
Median lethal dose is used in animal experiments. It s designed to determine how much of a substance can be taken before it becomes deadly. Animal testing is often done with rats. Substances are either fed by mouth, applied on the skin or injected into the veins.