What describes the rapid onset of severe symptoms due to a single exposure?

The term that describes the rapid onset of severe symptoms due to a single exposure is "acute toxicity." Acute toxicity refers to the effects that occur shortly after exposure to a hazardous substance, typically within 24 hours. This can arise from high levels of exposure to chemicals or toxins, resulting in immediate health effects, which may range from mild symptoms to severe reactions or even fatal outcomes.

Understanding acute toxicity is crucial for emergency responders, as it helps them quickly assess the situation and determine the appropriate response measures needed to minimize harm to individuals and the environment. The concept contrasts with chronic toxicity, which involves adverse effects from repeated exposure over a longer duration, or delayed toxicity, where symptoms manifest after a delay post-exposure. Subacute toxicity refers to effects that occur from repeated exposure over a timeframe longer than acute but shorter than chronic. Thus, acute toxicity is specifically associated with that alarming and immediate reaction following a single exposure event.