The influence of chemical and physical agents (specially radiation) on the frequency of mutations has been widely studied by means of the analysis of changes observed in Tradescantia, a plant used as a bioindicator. The evaluation of these genetic changes may be performed both by detection of somatic mutations or chromosome abnormalities induced by mutagens that are present in the air, soil, or water. The results obtained from several studies support the use of Tradescantia for monitoring the effects of ionizing radiation. Studies of mutagenicity and chromosomal abnormalities may be carried out in future to compare the effects of other types of radiation, evaluation of the effects of the combined use of radiation and drugs or other chemical agents, and to monitor high risk environments.

Keywords: Radiobiology, Mutation, Tradescantia, Ionizing radiation

Objective: To evaluate the effects of ionizing radiation on the taste function in patients submitted to radiotherapy in the head and neck region. Materials and Methods: Twenty patients diagnosed with head and neck tumors and undergoing treatment in the Division of Radiotherapy at Santa Casa de Misericórdia de Belo Horizonte, MG, Brazil, were selected. For their taste function testing, four solutions were manipulated with salt (NaCl), sugar (sucrose), citric acid (for acidity), and urea (for bitterness), at three different (low, medium and high) concentrations. Weekly tests were performed during the first three weeks of radiotherapy, with random administration of the solutions (three drops each) respecting the order of their concentration levels (low, medium and high). After the application of each solution, the patient reported which flavor he/she tasted. Results: A statistically significant difference was observed in the loss of taste function as the results in the 1st and 4th weeks of treatment were compared, with salty solution at the three concentration levels, with the sweet solution at low and medium concentrations, and with the sour and bitter solutions, only at low concentration. Conclusion: Ionizing radiation alters the taste function of patients submitted to head and neck radiotherapy.

Keywords: Ionizing radiation; Radiobiology; Ageusia.