January 7, 2009

Biological Effects of Radiation Used in Imaging (1): Non-stochastic Effect

What Determines Biological Effects of Radiation on Human?
3. Rate
4. Part of body
5. Age of individual
6. Biological difference among individual
The effects of ionizing radiation upon humans are often broadly classified as being either stochastic or nonstochastic.

• Acute effect, typically with a very large dose in a short time
• There is a threshold dose, i.e. exposure below this dose would not cause such effects.
• Severity (magnitude) of effect is directly proportional to dose.
• Evident in hours or days
• Erythema, burns, cataract, sterility, radiation sickness and death
• Not typical for imaging procedure, which typically employs lower dose of radiation
Reference:
NDT