What is risk assessment?

• A. The process of measuring the probability that a hazard will cause harm
• B. How to clean up spills
• C. Estimating cost of pollution
• D. Identifying contaminants

Answer: (A)

Risk assessment in toxicology is the process of estimating how likely a hazard is to cause harm under real-world conditions. It combines what a hazard can do (its potential to cause effect) with how much exposure people or the environment might have to it, as well as factors like duration, frequency, and susceptibility. In practice, risk assessment includes identifying the hazard, understanding the dose that can cause effects, evaluating how people are exposed, and then characterizing the overall risk by comparing exposure to the adverse effects that have been observed. This focus on the probability and magnitude of harm under actual conditions is what sets risk assessment apart from other activities.

So the best answer captures the idea of measuring the probability that a hazard will cause harm. The other options describe actions like cleanup, economic estimation, or merely identifying contaminants, which are related tasks but do not define the broader probabilistic assessment of risk.