Keywords: americium, lung clearance, modelling, systemic plutonium, internal dosimetry, radiochemical production, Russia, chemical-metallurgical production, nuclear workers, nuclear safety, dose estimation, low radiation, radiation exposure, radioactive nuclides
Status and prospects of internal dosimetry for the Mayak nuclear workers
Research results on internal dosimetry for workers at the radiochemical and chemical-metallurgical facilities of Mayak Production Association are summarised here. The leading role of plutonium in forming of internal doses in these workers is demonstrated. Biophysical, methodical and analytical principles currently used in monitoring of internal exposure due to incorporated plutonium are described. Capabilities of the techniques utilised are analysed. It is demonstrated that alpha radiometry does not meet the monitoring requirements related to sensitivity in some cases. Problems arising in the process of examination of nuclear workers are analysed. It is shown that the primary directions in the development of the internal dosimetry system imply improvement of plutonium metabolic models (including respiratory tract and extrapulmonary models), conversion to a more sensitive instrumental base when measuring plutonium content in biosubstrates, development of methods for dose estimation in terms of plutonium intake via wounds, and improvement of the worker's exposure scenario technique.