RADIOLOGICAL AND NUCLEAR TERRORISM - MEDICAL-BIOLOGICAL AND HYGIENIC PROBLEMS

Abstract

The main aspects of radiological and nuclear terrorism have been considered in the paper. The nuclear terrorism scenario, i.e. the usage of nuclear weapons by terrorists has been emphasized to look unlikely. While the threat of radiological terrorism related to the usage of radioactive materials with the purpose of malicious exposure to the public, for example, by detonating of a “dirty bomb” with further radioactive contamination of the environment where people live, or by a hidden usage of radioactive materials appears to be rather realistic. The character and consequences of the usage of various types and sources of ionizing radiation from alpha-emitting radionuclides to gamma-, gamma-beta or beta-emitting radionuclides under external, internal or contact exposure have been discussed. The criteria of radiation impact to a person are emphasized to include both the absorbed dose and absorbed dose rate. In the case of external exposure it is necessary to consider the character of the exposure: total (whole body exposure) or local (some parts of a body) to a person; in the case of the internal exposure - features of distribution and metabolic characteristics of a specific radionuclide. Deterministic effects (acute radiation sickness, local radiation injury, chronic radiation sickness) and stochastic effects (malignant tumors, hereditary diseases) are considered as effects of the radiation exposure. Under the comparison of a radiation threat due to different pathways as a result of an act of radiological terrorism usually the first place is taken by the external exposure, followed by the internal exposure by inhalation intake of radionuclides, in the case of dispersed radioactive materials due to detonation - through wounds and burned skin surfaces; the lesser important pathway is oral intake of radionuclides. The analysis of various scenarios of the radiological terrorism shows the number of casualties with deterministic effects will be small, while the number of people with stochastic effects will not be discernible from spontaneous variation of levels of the prevalence rate of malignant tumors and hereditary diseases. The main negative factor of radiological terrorism is psychological impact of the terrorism associated with a radiation threat