A rapidly developing adverse health effect with severe symptoms.

An adverse effect on any living organism in which severe symptoms develop rapidly and often subside after the exposure stops.

An adverse effect on a human or animal, following a single dose or short exposure with symptoms developing rapidly

Any toxic effect that is produced within a short period of time, generally 96 hours or less. Although the effect most frequently considered is mortality, the end result of an acute effect could be any harmful biological effect.

Adverse effect on a human or animal that has severe symptoms developing rapidly and coming quickly to a crisis.

one which involves severe symptoms which develop rapidly and may quickly reach a crisis.

A severe or immediate reaction to a hazard, usually resulting from a single, large exposure.