Which term indicates that an exposure at any level will increase the probability of having a negative effect?

• A. Non-threshold
• B. Rate of Entry
• C. Acute Exposure
• D. Flammable Liquid

Answer: (A)

The idea here is that some hazards have no safe exposure level—any amount can raise the chance of harm. This is captured by the term non-threshold, meaning there is no dose below which adverse effects are avoided. In toxicology, this implies a risk that increases with any additional exposure, even at very small levels, which is often the concept used for carcinogens modeled with a linear no-threshold approach. The other terms describe how exposure occurs or the material’s properties rather than whether a safe level exists: acute exposure refers to short-term exposure, rate of entry is about how quickly a contaminant enters the body, and a flammable liquid is a physical property relevant to fire risk, not dose-response safety.