American Registry of Radiologic Technologists (ARRT) Practice Exam

Stochastic effects are characterized as late effects of radiation exposure because they are associated with the probability of occurrence rather than the severity of the effect. This means that as the dose of radiation increases, the likelihood of developing a late effect, such as cancer or genetic mutations, increases, even if there is no threshold dose below which these effects do not occur. Typically, stochastic effects can manifest years or even decades after the initial radiation exposure, making them particularly concerning. Epidemiological studies have shown a correlation between exposure to low doses of radiation and an increased incidence of cancer, which is a key example of a stochastic effect. In contrast, deterministic effects, such as radiation burns or cataracts, occur within specific dose thresholds and typically present within a short timeframe after exposure. Acute effects refer to immediate reactions to high doses of radiation, such as radiation sickness, while immediate effects describe consequences occurring directly after radiation exposure. The distinguishing factor for stochastic effects lies in their dose-response relationship and their long-term consequences, reinforcing their classification as late effects of radiation.