Radiation risks and benefits in medical exposure and the role of regulatory authority in Tanzania

Medical procedures represent the largest source of human-made radiation exposure and ionizing radiation is firmly established as an essential tool for diagnosis and therapy in medicine, though pattern vary widely around the world. Diagnostic examinations are conducted mainly with x-rays (diagnostic radiology), nuclear medicine by administering radiopharmaceuticals to patients. Radiotherapy is mostly carried out using external beams of radiation (teletherapy), although some patients receive direct applications of sealed radionuclide sources (brachytherapy) or therapeutic administrations of radiopharmaceuticals. In medical exposure the exposed person is a direct recipient of an intended benefit that can be compared with the potential risk to that same individual, and the exposure is voluntary. On the basis of the linear, no-threshold dose-response approximation, no dose is regarded as completely safe. Therefore, diagnostic reference level cannot delineate dangerous from safe and are not efficient as tools to minimize radiation risks. Instead, optimization is the primary means of limiting risks to patients and this can only be achieved if there is a quality assurance programme in place. This paper point out radiation risks to patients from medical application and reviews inspection conducted by regulatory authority. (author)