Radiobiology of Accidental, Public, and Occupational Exposures

This chapter describes situations where individuals may be potentially exposed to ionizing radiation in accidental, occupational, or public exposures excluding those from clinical radiotherapy. Each exposure type can have very specific characteristics ranging in radiation quality, dose, dose rate, length of exposures, and proportion of the body acute exposure. As such, some long-term health effects of low-dose exposures are described including effects on the embryo and fetus, heritable diseases, cataracts, and cardiovascular effects. Special focus on exposure to radon is included along with the health effects specific to this exposure situation. Accidental and malicious exposures can also include high-dose scenarios that can lead to the development of acute radiation syndrome (ARS). Details of ARS are described along with how it can be diagnosed. In some exposure scenarios, large numbers of individuals are exposed such that triage is required to quickly identify those needing medical intervention to mitigate ARS. Strategies for triage for treatment are described with respect to trauma, contamination, and exposure along with a discussion of suggested countermeasures for internal exposure and medical follow-up after exposure. In order to assist with determining the dose of radiation an individual has been exposed to, several biodosimetry techniques are described. The final section focuses on the radiation protection system including definitions of quantities commonly used and the limits of exposure.