Acute toxicity occurs after: Repeated and/or prolonged exposures Single or short exposures Following exposure to a hazardous chemical Exactly 3 exposures

Acute toxicity typically occurs after a single or short exposure to a hazardous chemical. This form of toxicity is characterized by adverse effects that arise quickly after exposure, usually within 24 hours. Acute toxicity is often assessed through the measurement of the lethal dose or concentration that causes death or significant harm within a short period.

In contrast, multiple or prolonged exposures are generally associated with chronic toxicity, which develops over a longer time frame and can result from repeated exposure to lower doses of a toxic substance. Therefore, acute toxicity is not dependent on the number of exposures but rather on a sudden and significant dose received in a brief period.