Which statement best distinguishes acute vs chronic exposure?

• A. Acute is a short-term high exposure (e.g., solvent splash); chronic is repeated exposure over a long period (e.g., daily solvent vapor exposure)
• B. Acute exposure is a long-term, low-level exposure
• C. Acute exposure occurs only in the first hour of work
• D. Acute exposure is a one-time event

Answer: (A)

The key idea here is that acute versus chronic exposure is about the pattern over time: how long the exposure lasts and how often it occurs. Acute exposure refers to a brief, high-intensity contact with a substance—a single, sharp event like a solvent splash. Chronic exposure, on the other hand, involves repeated or continuous exposure over a long period, such as daily solvent vapor exposure.

That is why the statement describing acute as a short-term high exposure (a solvent splash) and chronic as repeated exposure over a long period (daily solvent vapor exposure) is the best fit. It clearly contrasts duration and frequency in a way that matches how these types of exposure are typically observed.

The other ideas don’t fit as well because they either misstate the duration or imply something too narrow (for example, that acute exposure must occur only in the first hour, or that it is always a one-time event), which doesn’t capture the usual patterns of how acute and chronic exposures occur in real work settings.