Browsing by Author "Ozbay, Turkan"

Now showing 1 - 4 of 4

Citation - WoS: 3
A Comparative Study on Indoor Radon Levels Between the Lung Cancer and Cancer Free Groups in Izmir Province, Turkey
(Dokuz Eylul Univ Inst Health Sciences, 2021) Ozbay, Turkan; Karadeniz, Ozlem; Cilengiroglu, Ozgul Vupa; Durak, Hatice; Eser, Sultan
Purpose: Izmir is the province of Turkey with the highest lung cancer incidences for males, therefore a comparative study was performed in particular districts of Izmir in 2013. In the study, it was aimed to assess the association between lung cancer risk and indoor radon. Methods: Patients diagnosed with lung cancer between 2010 and 2011 were selected from the database of the Izmir Cancer Registry (ICR). Measurements of indoor radon concentrations were performed in a total of 117 locations using the SSNTD (Solid State Nuclear Track Detectors) method with LR-115 detectors. Indoor radon concentration measured in homes of patients with lung cancer and cancer free group were compared statistically. Results: The indoor Radon (222Rn) activity concentration detected ranged from 165 to 487 Bq/m3, for the lung cancer group, from 28 to 367 Bq/m(3) for the cancer free group, with geometric means of 269 Bq/m3 and 123 Bq/m(3), respectively. Conclusion: According to the logistic regression model, as radon concentration and package/year increased, the rate of cancer increased multiple folds. These results suggest that indoor radon levels may contribute to higher rates of lung cancer for Izmir compared to the rest of the country, and indoor radon levels may be a contributory factor in this phenomenon.
Citation - WoS: 6
Citation - Scopus: 5
Indoor Radon Measurement in Izmir Province, Turkey
(Taylor & Francis Ltd, 2016) Ozbay, Turkan; Karadeniz, Ozlem
In 2013, an extensive study was performed in a total of 117 locations in Izmir province and indoor radon levels were measured using the alpha track etch integrated method with LR-115 detectors. As the maps are more practical to interpret the results of radiological survey' he distributions of indoor Rn-222 activities in four most densely populated districts of Izmir were mapped in detail. It is seen that the estimated average radon concentration level (210 Bq m(-3)) determined in Izmir province was almost three times higher than the mean value for Turkey (81 Bq m(-3)). Exposed annual effective dose equivalents for Izmir province were estimated in the range of 0.7 to 2.3 mSy year(-1) with a mean of 5.3 mSv year(-1). In this study, it is pointed out that indoor radon concentration was affected by the age f the building and height above the ground.
Citation - WoS: 2
Citation - Scopus: 2
Preliminary Dose Estimation From Indoor Radon for the Medical Staff of Radiation Oncology and Nuclear Medicine
(Taylor & Francis Inc, 2016) Karadeniz, Ozlem; Gunalp, Gun; Ozbay, Turkan; Demiral, Ayse Nur
The aim of this preliminary study was to measure the indoor radon activity concentration in the houses and offices of Radiation Oncology and Nuclear Medicine staff at Dokuz Eylul University and to assess the results from a radiological perspective. LR-115 type II solid-state nuclear track detectors were installed in the homes and hospital and were exposed for 2months. LR-115 type II detectors were etched for 90min in 10% (2.5M) NaOH solution at 60 degrees C and radon activity concentration was determined from observed microscopic track densities. It was observed that measured indoor radon concentration ranged between 18 and 624Bq/m(3) with a geometric mean of 95Bq/m(3) in hospital, and between 22 and 560Bq/m(3) with a geometric mean of 129Bq/m(3) in homes. Estimates of the annual effective dose received by medical staff who participated in the study ranged between 0.76 and 8.79mSv. On average, the hospital building contributed 41% to the annual effective dose. The reported values for radon concentrations and the corresponding estimated annual effective equivalent doses were within the limits recommended by the International Commission on Radiological Protection as well as the Turkish Atomic Energy Commission recommended limits for workplaces and houses.
Citation - WoS: 1
Simulation of Water Equivalency of Polymer Gel Dosimeters With Gamos
(Aves Press Ltd, 2020) Ozbay, Turkan; Yurt, Aysegul; Ozsoykal, Ismail
Purpose: Polymer gel materials are used as dosimeters to provide three dimensional radiation dose distribution. An ideal gel dosimeter should offer radiological properties equivalent to water. This study aims to determine and compare the water equivalencies of various new polymer gel mixtures using Geant4-based Architecture for Medicine-Oriented Simulations (GAMOS) software program. Methods: To do this, percentage depth dose curves of the simulated polymer gel mixtures were compared with water curves. Different combinations of materials from 2 main classes were used in the mixtures: (1) Sodium Carboxymethyl Cellulose (SODIUM CMC), Polyvinyl Alcohol (PVA) and Polyethylene Glycol (PEG) as gel matrix, (2) 2-Hydroxyethyl Methacrylate (HEMA), 1-Vinyl-2-Pyrrolidinone (VP) and Diethylene Glycol Dimethacrylate (DEGDMA) as monomer. Each mixture also contained ultra-pure water and an antioxidant material called Tetrakis Hydroxymethyl Phosphonium Chloride ( THPC). Results: Percentage depth doses of gel mixtures and water was calculated for 6, 18 MV and 50, 70, 100, 150 kVp X rays. The mixture sample showing radiological behavior nearest to water over all energies was observed to be 31a (Water, PEG, HEMA, THPC), while the largest difference is observed in 11a (Water, SODIUM CMC, HEMA, THPC). Conclusion: As a result, simulated gel formulations were found to be radiologically water equivalent.