Which exposure type is repeated exposures at lower concentrations over long periods of time?

• A. Non-threshold
• B. Acute Exposure
• C. Exposure Routes
• D. Chronic Exposures

Answer: (D)

Chronic exposure refers to repeated or continuous contact with a contaminant at low concentrations over a long period, so the total dose accumulates over time. This pattern matters because even small amounts can add up and lead to health effects after months or years of exposure, which is why this term describes long-duration, low-level contact.

This differs from an acute exposure, which is a single event or short-term high-dose encounter. The other terms don’t capture the duration aspect: non-threshold is about whether a substance has a safe exposure level, not how long exposure lasts, and exposure routes describe how the contaminant enters the body (inhalation, ingestion, dermal) rather than the time pattern of exposure.