Final answer:
The correct term describing a dose that is lethal to 50% of the test population by non-inhalation routes is Lethal Dose 50 (LD50). It is a measure of a substance's acute toxicity and varies depending on species and administration methods.
Step-by-step explanation:
The term that describes a single dose of a substance that causes the death of 50% of the test population by a route other than inhalation is known as the Lethal Dose 50 (LD50). This term is crucial in toxicology as it helps quantify the acute toxicity of a substance, giving an indication of how deadly a substance can be to a population, typically laboratory animals like rats or mice. The LD50 is expressed as the amount of substance per body weight of the test animal, usually in milligrams per kilogram (mg/kg).
For example, It provides LD50 values for various insecticides, demonstrating that a lower LD50 value signifies a higher level of toxicity. It is important to recognize that LD50 values can vary depending on different species and the method of administration of the substance, thus LD50 is used as a general guide rather than an absolute measure of risk to humans. Notably, the LD50 is different from the Effective Dose 50% (ED50), which refers to the dose causing a significant response in 50% of the population, not necessarily death.
So the correct answer to the student's question is Option 3: Lethal Dose 50 (LD50). Options such as Lethal Inhalation Dose (LID), Median Lethal Dose (MLD), and Acute Toxicity Dose (ATD) are incorrect or not standard terms used in toxicology for the concept described.