Chronic toxicity refers to harmful effects that occur after:

• A. many exposures over time
• B. a single exposure
• C. exposure during infancy only
• D. short-term exposure under 24 hours

Answer: (A)

Chronic toxicity arises from long-term or repeated exposure to a substance, allowing damage to accumulate or develop over time. When exposure happens many times across days, months, or years, adverse effects may take time to manifest as the body’s systems are affected cumulatively. This contrasts with acute toxicity, where harmful effects show up soon after a single exposure. So repeated exposures over an extended period best describe chronic toxicity, while a one-time exposure, brief exposure, or age-specific-only exposure isn’t the defining pattern.