What is defined as acute toxicity?

Acute toxicity refers to the measure of harm that can result from a single exposure event to a substance. This type of toxicity is assessed based on the immediate effects that occur after exposure, typically within a short timeframe, often within 24 hours to a few days. Understanding acute toxicity is crucial in fields like pest control and toxicology, as it helps professionals evaluate how dangerous a chemical may be following a one-time incident, such as a spill or application. This concept is particularly important when identifying safe levels of exposure and determining necessary safety precautions.

The other options pertain to different concepts: cumulative effect relates to long-term exposure and does not apply to acute toxicity; resistance deals with an organism's ability to withstand certain chemicals, which is not directly linked to the immediate effects of acute toxicity; and gradual build-up refers to bioaccumulation, where substances accumulate over time in an organism, rather than the effects of a one-time exposure.