Which example shows a linear nonthreshold dose-response relationship?

Which example shows a linear nonthreshold dose-response relationship?

• A. genetic effects
• B. radiation-induced cancer
• C. leukemia
• D. all of the above

Answer: (D)

The linear no-threshold dose-response idea means any amount of radiation carries some risk, and that risk increases in direct proportion to the dose with no safe, zero-risk level. Under this model, stochastic effects like genetic effects, radiation-induced cancer, and leukemia are treated as having no safe threshold and a straight-line increase in risk from zero as dose rises. Since all three are considered to follow this pattern for regulatory risk assessment, the option that includes all of them is the best fit. Note that in real biology there can be complexities at very low doses or for different endpoints, but for purposes of this concept and exam style, these examples are all modeled with linear no-threshold behavior.

The linear no-threshold dose-response idea means any amount of radiation carries some risk, and that risk increases in direct proportion to the dose with no safe, zero-risk level.

Under this model, stochastic effects like genetic effects, radiation-induced cancer, and leukemia are treated as having no safe threshold and a straight-line increase in risk from zero as dose rises. Since all three are considered to follow this pattern for regulatory risk assessment, the option that includes all of them is the best fit.

Note that in real biology there can be complexities at very low doses or for different endpoints, but for purposes of this concept and exam style, these examples are all modeled with linear no-threshold behavior.