Exposure that occurs over a short period of time is called:

Exposure that occurs over a short period of time is referred to as acute exposure. This term is specifically used in the context of health effects and environmental hazards to describe instances where an individual experiences a high level of exposure to a hazardous substance for a brief duration. Acute exposure can lead to immediate adverse health effects, which may be severe or minor, depending on the substance and the level of exposure.

In contrast, chronic exposure refers to the long-term exposure to lower levels of a hazardous substance, which may develop over months or years and can lead to cumulative health effects. The other terms provided, such as concentrated and permissible, do not accurately describe exposure duration in the same way. Concentrated typically refers to the amount or density of a substance rather than the timeframe of exposure, and permissible relates to limits set for exposure levels that are legally acceptable, rather than the duration of exposure itself.