LC50 and LD50 are used to measure which characteristic of chemicals?

• A. Hazard & toxicity
• B. Death
• C. Different product's modes of action
• D. Different product's formulation

Answer: (A)

LC50 and LD50 measure a chemical's acute toxicity, which reflects its hazard. LC50 is the concentration that kills 50% of a tested population, typically for inhalation or aquatic exposure, while LD50 is the dose that kills 50% of the population, usually for oral or dermal exposure. The key idea is that these values show the amount of exposure needed to cause death in half of the subjects, so smaller numbers mean a more toxic substance and larger numbers indicate lower acute toxicity. They’re used to compare hazards and inform safety standards. These metrics describe the potential for harm from exposure, not the chemical’s specific mode of action or differences in product formulation.