Acute vs chronic toxicity: which statement is correct?

• A. Acute toxicity results from a single or short-term exposure; cyanide poisoning; Chronic toxicity results from long-term exposure; lead neurotoxicity
• B. Acute toxicity results from long-term exposure; cyanide poisoning; Chronic toxicity from a single short-term exposure; lead neurotoxicity
• C. Acute toxicity is a measure of lifetime exposure
• D. Acute toxicity and chronic toxicity are the same

Answer: (A)

Acute toxicity is about effects that occur after a short-term exposure, often a single event, with rapid onset and potentially immediate harm. Chronic toxicity, on the other hand, arises from long-term or repeated exposure over months or years, with damage that accumulates over time.

The statement that pairs cyanide poisoning with a brief exposure as the acute case and lead neurotoxicity with long-term exposure as the chronic case is the best fit. Cyanide can cause rapid, life-threatening effects after a short exposure, illustrating acute toxicity. Lead, especially in children, tends to cause problems only after long-term exposure, reflecting chronic toxicity due to cumulative damage.

The other options mix up the timing and nature of exposure (long-term exposure for acute, or single short-term exposure for chronic), or incorrectly define acute toxicity as lifetime exposure, or claim the two are the same.