Which statement best describes acute vs chronic exposure?

• A. Acute exposure is a single or short-term exposure with immediate effects; chronic exposure is repeated exposure over long periods.
• B. Acute exposure is long-term with cumulative effects.
• C. Chronic exposure is a single event; acute exposure is repeated exposure.
• D. Neither term is used in occupational health.

Answer: (C)

Duration and immediacy of effects differentiate acute from chronic exposure. Acute exposure is a short-term or single-event exposure where effects appear quickly after the exposure. Chronic exposure involves repeated or continuous exposure over long periods, often with cumulative health effects even if individual exposures are small. The best description matches this: acute exposure is a short-term or single event with immediate effects, while chronic exposure is repeated exposure over long periods. For example, inhaling a high concentration of a chemical for a few minutes can cause immediate effects (acute), whereas daily exposure to a low level of the same chemical over years can lead to long-term health changes (chronic). The other statements don’t fit: acute exposure is not defined as long-term, chronic is not a single event, and these terms are standard in occupational health.