Effect of radon measurement methods on dose estimation.

Different radon measurement methods were applied in the old and new buildings of the Turkish bath of Eger, Hungary, in order to elaborate a radon measurement protocol. Besides, measurements were also made concerning the radon and thoron short-lived decay products, gamma dose from external sources and water radon. The most accurate results for dose estimation were provided by the application of personal radon meters. Estimated annual effective doses from radon and its short-lived decay products in the old and new buildings, using 0.2 and 0.1 measured equilibrium factors, were 0.83 and 0.17 mSv, respectively. The effective dose from thoron short-lived decay products was only 5 % of these values. The respective external gamma radiation effective doses were 0.19 and 0.12 mSv y(-1). Effective dose from the consumption of tap water containing radon was 0.05 mSv y(-1), while in the case of spring water, it was 0.14 mSv y(-1).

Comparison of urinary excretion of radon from the human body before and after radon bath therapy.

Theoretically, the human body absorbs radon through the lungs and the skin and excretes it through the lungs and the excretory organs during radon bath therapy. To check this theory, the radon concentrations in urine samples were compared before and after radon bath therapy. During the therapy, the geometric mean (GM) and the geometric standard deviation of the radon concentration in air and in the bath water were 979 Bq m(-3), 1.58 and 73.6 Bq dm(-3), 1.1, respectively. Since radon was detected in each urine sample (GM around 3.0 Bq dm(-3)), urinary excretion of radon was confirmed. The results of this study can neither reject nor confirm the hypothesis of radon absorption through the skin. A 15 times higher increment of inhaled radon level did not cause significant changes in radon of urine samples.

Study on endocronological effects of radon speleotherapy on respiratory diseases.

BACKGROUND: Radon, as a radioactive noble gas of natural origin, is generally present in the atmosphere of caves during the speleotherapeutic treatment of different diseases. However, the role of radon in the therapeutic effect is not fully clarified yet. Endocrine parameter levels may be influenced by radon-like endocrine levels in balneotherapeutic treatments (bath treatment). For this reason changes of these parameters were examined in this study. PATIENTS AND METHOD: A total of 81 speleotherapy patients were involved in the survey. They spent four hours daily in Tapolca Cave, five days a week, for two weeks. In this study, the thyreoiedea stimulating hormone, free triiodine-tironin, free thyroxine, prolactine, cortisol, dehydroepiandrosterone sulphate, adrenocorticotropic hormone, and beta endorphine levels of the body were examined before and after the treatment. RESULTS: After statistical analysis of the data a significant decrease of cortisol levels of patients was found, which was not directly correlated with radon concentration. In the case of thyroid hormones, there were no significantly detectable changes of the hormone levels except for low radon concentration levels a significant decrease in the free thyroxine and the thyreoiedea stimulating hormone level of male patients was observed. CONCLUSION: Speleotherapy has an effect on the level of endocrine hormones; however, no direct correlation with differences in radon level was found. For patients whose endocrine levels fell outside the normal endocrine parameter values, more striking changes in endocrine hormone levels were seen, but changes of these parameters could not be statistically analyzed due to the small number of cases.

Does balneotherapy with low radon concentration in water influence the endocrine system? A controlled non-randomized pilot study.

Radon bath is a well-established modality of balneotherapy for the management of degenerative musculoskeletal disorders. The present study was conducted to ascertain whether baths of relatively low (80 Bq/l) radon concentration have any influence on the functioning of the endocrine system. In the study, a non-randomized pilot study, 27 patients with degenerative musculoskeletal disorders received 30-min radon baths (of 31-32 degrees C temperature and 80 Bq/l average radon concentration) daily, for 15 days. Twenty-five patients with matching pathologies were subjected to balneotherapy according to the same protocol, using thermal water with negligible radon content (6 Bq/l). Serum thyroid stimulating hormone, prolactin, cortisol, adrenocorticotropic hormone, and dehydroepiandrosterone levels were measured before and after a balneotherapy course of 15 sessions. Comparison of the accumulated data using the Wilcoxon test did not reveal any significant difference between pre- and post-treatment values or between the two patient groups. It is noted that while the beneficial effects of balneotherapy with radon-containing water on degenerative disorders is widely known, only few data have been published in the literature on its effect on endocrine functions. The present study failed to demonstrate any substantial effect of thermal water with relatively low radon content on the functioning of the endocrine system.

DOTTADs--readily made novel metal ligands with multivariant functionality--trans-DOTTADs and semi-DOTTADs.

Two new ligand systems related to the previously described DOTTADs have been generated in a simple one step reaction. The first, trans-DOTTADs, were formed by Vilsmeier formylation (followed by cyclisation and N-demethylation) of 2,6-dimethyl-3,5-pyrazine-dicarboxylic acid, to give the novel bis-pyridinopyrazine dialdehyde ligands. The corresponding pyrazine diester, reacted similarly to an intermediate iminium ion stage, which gave trans-DOTTAD imines on work-up with amines. The treatment of Hantzsch ester with two equivalents of benzaldehyde gave 7-phenyl-2-(2-phenylethenyl)-7,8-dihydropyrano[4,3-b]pyridin-5-one-3-carboxylic acid. This product underwent similar cyclisation with Vilsmeier reagents to give, for example, 6-methyl-2-(2-phenylethenyl)-8-(phenylhydroxymethyl)-6H-[1,6]naphthyridin-5-one-3-carboxylic acid, an example of a semi-DOTTAD.