Which statement best defines acute toxicity?

• A. Toxic effects that occur immediately after exposure to a substance.
• B. Chronic health effects that develop after prolonged exposure.
• C. Toxic effects that only occur at high ambient temperatures.
• D. Any toxic effect that requires ingestion to appear.

Answer: (A)

Acute toxicity means the adverse effects appear quickly after a brief or single exposure to a substance, typically within a day. That’s why describing effects as occurring immediately after exposure best fits the concept. It contrasts with chronic toxicity, where health problems arise after long-term or repeated exposure. Toxic effects can arise from inhalation, skin contact, or ingestion, so saying they only occur with ingestion is too narrow. Environmental factors like high ambient temperatures aren’t what define acute toxicity, though they can influence toxicity in other contexts.