Measurements of radon concentration levels in thermal waters in the region of Konya,Turkey

²²²Rn (radon) is one of the most important sources of natural radiation to which people are exposed. It is an alpha-emitting noble gas and it can be found in various concentrations in soil, air and in different kinds of water. In this study, we present the results of radon concentration measurements in thermal waters taken from the sources in the region of Konya located in the central part of Turkey. The radon activity concentrations in 10 thermal water samples were measured by using the AlphaGUARD PQ 2000PRO radon gas analyser in spring and summer of the year 2012. We found that radon activity concentrations range from 0.60±0.11 to 70.34±3.55 kBq m^?3 and from 0.67±0.03 to 36.53±4.68 kBq m^?3 in spring and summer, respectively. We also calculated effective doses per treatment in the spas for the spring and summer seasons. It was found that the minimum and maximum effective doses per treatment are in the range of 0.09–10.13 nSv in spring and in the range of 0.1–5.26 nSv in summer.     

Stable Isotope Ratios and Uric Acid Preservation in Termites Belonging to Three Feeding Habits in Thailand

Abstract

Nitrogen and carbon stable isotope ratios and uric acid concentrations in termites sampled from a dry evergreen forest in Thailand, were determined across three kinds of feeding habits. Feeding habits of Microcerotermes crassus, which is an abundant woodfeeder, and Dicuspiditermes makhamensis, a common soil-feeding termite, were confirmed by isotopic signatures. Lichen feeding termites (Hospitalitermes birmanicus, H. bicolor and H. ataramensis) were characterized by low δ¹⁵N values, suggesting that they assimilated nitrogen deposited from the atmosphere. There was also a significant difference in uric acid concentrations between termites representing different feeding habits. No significant relationships were found between uric acid concentrations and δ¹⁵N or δ¹³C in Hospitalitermes. However, δ¹⁵N values were correlated with C/N ratios in H. birmanicus, except in one colony of H. ataramensis. δ¹³C values in both species were negatively correlated with C/N ratios.     

Natural radioactivity and radiation hazards assessment of soil samples from the area of Tuzla and Lukavac,Bosnia and Herzegovina

The results of activity concentration measurements of natural occurring radioactive nuclides ²³⁸U, ²³⁵U, ²³²Th, ²²⁶Ra, and ⁴⁰K in surface soil samples collected in the area of cities Tuzla and Lukavac, northeast region of Bosnia and Herzegovina were presented. Soil sampling was conducted at the localities that are situated in the vicinity of industrial zones of these cities. The measured activity was in the range from (8?±?4) to (95?±?28) Bq kg^–1 for ²³⁸U, from (0.41?±?0.06) to (4.6?±?0.7) Bq kg^–1 for ²³⁵U, from (7?±?1) to (66?±?7) Bq kg^–1 for ²³²Th, from (6?±?1) to (55?±?6) Bq kg^–1 for ²²⁶Ra, and from (83?±?12) to (546?±?55) Bq kg^–1 for ⁴⁰K. In order to evaluate the radiological hazard of the natural radioactivity for people living near industrial zones, the absorbed dose rate, the annual effective dose and the radium equivalent activity have been calculated and compared with the internationally approved values.     

Determination of the health hazards due to background radiation sources in the city of Adapazari,Northwestern Turkey

Human body is exposed to ionising radiations both internally and externally by mainly high-energy cosmic ray particles incident on the earth's atmosphere and radioactive nuclides that originated in the earth's crust. The main objective of this study is to assess the health hazards due to environmental radiation sources in the city of Adapazari, one of the most important industrial cities of the country, Northwestern Turkey. For this purpose, natural radiation sources, external terrestrial radiations, cosmic radiations, and inhalation exposures have been investigated. The annual average external terrestrial radiation doses were determined as 0.08 and 0.35 mSv at outdoor and indoor atmospheres, respectively. The annual average cosmic radiation doses were found to be 0.08 and 0.05 mSv for directly ionising photon components and neutron components, respectively. The annual average inhalation exposure doses due to radon and thoron were obtained as 1.42 and 0.19 mSv, respectively, in the region. The annual average effective dose due to natural radiation sources was determined as a total of 2.35 mSv with the predetermined ingestion radiation dose. The lifetime cancer risk due to the background ionising radiations has been determined as 0.9×10^?2 for the residents of the Adapazari city, with the average lifespan of 70 years. The results of the effective doses due to background radiation sources in the region and the worldwide averages were discussed.     

Time variations of 222Rn concentration and air exchange rates in a Hungarian cave

A long-term radon concentration monitoring was carried out in the Pál-völgy cave, Budapest, Hungary, for 1.5 years. Our major goal was to determine the time dependence of the radon concentration in the cave to characterise the air exchange and define the most important environmental parameters that influence the radon concentration inside the cave. The radon concentration in the cave air was measured continuously by an AlphaGuard radon monitor, and meteorological parameters outside the cave were collected simultaneously. The air's radon concentration in the cave varied between 104 and 7776 Bq m^?3, the annual average value was 1884±85 Bq m^?3. The summer to winter radon concentration ratio was as high as 21.8. The outside air temperature showed the strongest correlation with the radon concentration in the cave, the correlation coefficient (R) was 0.76.     

Radioactivity measurements and risk assessments of spa waters in some areas in Turkey

The current study presents the results of the activity of radionuclides in spa waters, and evaluates their radiological influences on the population consuming these waters in the Central and Eastern Black Sea regions of Turkey. Since these waters are used for therapy and consumption purposes unconsciously, their radiological impact on the people was computed by taking into consideration the annual intake through ingestion of ²²⁶Ra, ²³²Th, ⁴⁰K, ¹³⁷Cs and ²²²Rn. The mean activities were estimated to be 11.35 for gross alpha, 6.23 for gross beta, 2.96 for ²²⁶Ra, 0.42 for ²³²Th, 0.069 for ¹³⁷Cs, 0.19 for ⁴⁰K, and 267 Bq L^–1 for ²²²Rn, respectively. The estimated effective doses from spa water were found to be 49.77 µSv a^–1 (²²⁶Ra), 5.95 µSv a^–1 (²³²Th), 0.07 µSv a^–1 (¹³⁷Cs), 0.83 µSv a^–1 (⁴⁰K) and 56.03 µSv a^–1 (²²²Rn). These values were evaluated and compared with related verified values from literature. Also, physico-chemical characterizations of spa water samples considered in the current study were investigated. This study would be useful for consumers and official authorities for the assessment of radiation exposure risk due to usage of the considered spa waters.     

Mineralogical,geochemical and radiological characterisation of Selmo Formation in Batman area,Turkey

This work deals with the mineralogical, geochemical and radiological characterisations of Selmo Formation in Batman neighbourhood. The upper Miocene–Pliocene Selmo Formation is common in the centre of Batman and composed of carbonated sandy claystones and silty–sandy stone lenses. The common whole minerals of the samples are quartz, feldspars, calcite and dolomite. The clay minerals are smectite, illite, chlorite and mixed-layer clay (chlorite–smectite). The geochemical mean values of the samples are 51.7% SiO₂; 12.6% Al₂O₃; 6.2% Fe₂O₃; 3.6% MgO; 6.3% CaO; 1.1% Na₂O; 1.7% K₂O; 0.8% TiO₂; 0.2% P₂O₅; 0.1% MnO; and 0.03% Cr₂O₃. In addition, baseline maps for the concentrations of each radionuclide, the radium equivalent activity and the outdoor gamma dose rate distributions have been plotted for the study area. The mean activity concentrations of ²²⁶Ra, ²³²Th, ⁴⁰K and ¹³⁷Cs were determined to be 32, 24, 210 and 9 Bq kg^?1, respectively. The assessments of the radiological hazard indices, such as radium equivalent activity, absorbed dose rate in air, annual effective dose equivalent, excess lifetime cancer risk, external hazard index and internal hazard index, were calculated and compared with the internationally accepted reference values. This study shows that the concentrations of radioactivities in the measured samples were within the recommended safety limits and did not pose to be any significant source of radiation hazard.     

Assessment of radiological hazard parameters due to natural radioactivity in soils from granite-rich regions in Kütahya Province,Turkey

The analysis of natural radioactivity from ²³⁸U, ²³²Th and ⁴⁰K in 357 soil samples collected from the province of Kütahya was carried out using a NaI(Tl) gamma-ray spectroscopy system at the Nuclear Physics Research Laboratory, Dumlup?nar University, Kütahya, Turkey. The specific activities of ²³⁸U, ²³²Th and ⁴⁰K in the soil samples were evaluated. From the activity concentrations of ²³⁸U, ²³²Th and ⁴⁰K, the total absorbed outdoor gamma-ray dose rates and the corresponding annual effective dose rates were determined. The corresponding values of the external and internal hazard indices of all the soil samples were also calculated. The external gamma-ray dose rate at 1 m above the ground was directly measured at each collected soil sample location. The results obtained in this study were compared within the limits of values obtained in other cities of Turkey, those in other countries. Radiological maps of Kütahya Province were constructed from the results of this study.     

Radioactivity in Montenegro beach sands and assessment of the corresponding environmental risk

Activity concentrations of the naturally occurring radionuclides ²²⁶Ra, ²³²Th, ⁴⁰K and anthropogenic ¹³⁷Cs in sand samples collected from 20 renowned beaches on the Coast of Montenegro have been determined using an HPGe (high purity Ge spectrometer). The average activity concentrations were found to be 7.4, 5.2, 97.3 and 0.5 Bq kg^?1, respectively. For all sand samples, the radium equivalent activity has been evaluated and found to be lower than the limit of 370 Bq kg^?1. External and internal hazard indices were less than unity. The gonadal dose equivalent was estimated to be on average 75 μSv y^?1, which is about four times lower than the global average for soil (0.3 mSv y^?1). Calculated values of absorbed dose rates showed the range from 3.1 to 28 nGy h^?1, which is below the world median of average values (57 nGy h^?1). The effective dose rate in the range from 3.8 to 34.4 μSv y^?1 was significantly below the recommended limit value for the public (1 mSv y^?1). The highest dose rate was found for the Velika Plaza locality, which also showed heavy metal contents (As, B, Cd, Hg, Cr, Cu, Mn, Ni, Pb, Zn and Ba) significantly higher than in the sand from Jaz, a locality with one of the lowest dose rates.     

In situ measurements of radon levels in water and soil and exhalation rate in areas of Malwa belt of Punjab (India)

Radon concentration levels in water and soil gas from 36 locations pertaining to some areas of Malwa region of Punjab have been measured on an in situ basis using a continuous active radon detector (AlphaGuard, Model – PQ 2000 PRO, Genitron instruments, Germany). Exhalation rate measurements have also been carried out at these places, using a closed-circuit technique. The radon concentrations in soil and water varied from 1.9 to 16.4 kBq m^?3 and 5.01 to 11.6 kBq m^?3, respectively. The exhalation rate (E _Rn) ranged between 7.48 and 35.88 mBq m^?2 s^?1 with an average value of 18.17 mBq m^?2 s^?1. Annual dose rates have been calculated for water radon concentrations. The minimum to maximum values of dose rates were found to be 13.42–31.08 μSv y^?1. The recorded values of radon concentration in water are within the safe limit of 11 Bq l^?1 recommended by the US Environment Protection Agency [National Research Council, Risk Assessment of Radon in Drinking Water (Academy Press, Washington, DC, USA, 1999)]. All measurements were made in similar climatic and environmental conditions to ensure minimal variations in meteorological parameters. An intermediate correlation coefficient (0.5) was observed between radon exhalation rates and soil gas values.     

The highest background radiation school in the world and the health status of its students and their offspring

Although the average effective human dose from natural background radiation is about 2.4 mSv per year, the students of the Saeid Nafisi school in Ramsar received effective doses of about 250 mSv while studying there for over 5 years. The goal of this project was a retrospective study of the health status of former students of this school and their offspring. The list of the students of the Saeid Nafisi school (high background radiation) and Taleghani and Kashani schools (ordinary background radiation) was provided by the Department of Education. After matching sex, age and socioeconomic level and obtaining their consent, part 1 of the specifically designed questionnaire was filled out by interview, and clinical examinations were recorded in part 2 of the questionnaire by a physician. The data were analysed using Statistical Package for the Social Sciences 16. Our study shows that 88.1 % of general examinations of high background radiation school students were normal as compared with 85.7 % for control group. There were no significant differences. This study is interesting and unique. It reveals that there is no health emergency related to these high radiation doses. We recommend continuing the health supervision of this population in the future.     

Comparison of active and passive radon survey in cave atmosphere,and estimation of the radon exposed dose equivalents and gamma absorbed dose rates

Radon (²²²Rn) measurements were conducted in the Pileki Cave with Radim 3A Active Radon Monitor equipment. Measurements were also done with the passive sampling method with CR-39 nuclear track detectors by exposing them for three months in the cave. Radon concentrations obtained from the active and passive sampling methods showed that, firstly, the concentrations inside the cave measured by the latter method differed greatly due to high humidity levels up to 88%. The total inside radon exposure dose equivalent people were subjected to was estimated to be 19?µSv a^?1 for visitors and 24,065?µSv a^?1 for guides. The gamma absorbed dose rates were determined for inside and outside the cave. The dose rates were calculated by means of using the ²²⁶Ra, ²³²Th and ⁴⁰K activity concentrations and by means of real-time measurements. The gamma absorbed dose rates were found to be much higher than the value of 55?nGy?h^?1 given by UNSCEAR. In addition, the mineralogical compositions and elemental analyses of samples taken from the cave were determined by XRD and WD-XRF methods.     

Fission products from the damaged Fukushima reactor observed in Hungary

Fission products, especially ¹³¹I, ¹³⁴Cs and ¹³⁷Cs, from the damaged Fukushima Dai-ichi nuclear power plant (NPP) were detected in many places worldwide shortly after the accident caused by natural disaster. To observe the spatial and temporal variation of these isotopes in Hungary, aerosol samples were collected at five locations from late March to early May 2011: Institute of Nuclear Research, Hungarian Academy of Sciences (ATOMKI, Debrecen, East Hungary), Paks NPP (Paks, South-Central Hungary) as well as at the vicinity of Aggtelek (Northeast Hungary), Tapolca (West Hungary) and Bátaapáti (Southwest Hungary) settlements. In addition to the aerosol samples, dry/wet fallout samples were collected at ATOMKI, and airborne elemental iodine and organic iodide samples were collected at Paks NPP. The peak in the activity concentration of airborne ¹³¹I was observed around 30 March (1–3 mBq m^?3 both in aerosol samples and gaseous iodine traps) with a slow decline afterwards. Aerosol samples of several hundred cubic metres of air showed ¹³⁴Cs and ¹³⁷Cs in detectable amounts along with ¹³¹I. The decay-corrected inventory of ¹³¹I fallout at ATOMKI was 2.1±0.1 Bq m^?2 at maximum in the observation period. Dose-rate contribution calculations show that the radiological impact of this event at Hungarian locations was of no considerable concern.     

Geological influence on the activity concentration of terrestrial radionuclides 226Ra, 232Th and 40K in the Jos Plateau,Nigeria

The Jos Plateau has been reported to have elevated levels of natural background radiation. A few earlier studies have measured the levels of natural radioactivity for specific locations in the area. Our interest is to investigate how geology of the study area influences the activity concentrations of natural radionuclides. Thus, the activity concentrations of terrestrial radionuclides in soil samples collected across the geological formations of the Jos Plateau were determined by gamma spectrometry technique. The mean activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K were found to exceed their corresponding world reference values of 35, 40 and 400?Bq?kg^?1, respectively. Data were compared using statistical methods, analysis of variance (ANOVA) and post hoc tests. The results revealed in some instances significant influences of geological types on the activity concentrations in the area. The spatial distribution maps of activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K were geostatistically interpolated by ordinary Kriging method using ArcGIS software.     

Unexpected radiation hazard in dyes of textiles

Textile dyes are among the most problematic pollutants because of their toxicity on several organisms and ecosystems. Many of the chemicals used in the textile industry may represent some health concerns. The determination of the radioactivity in textile dyes is therefore very important for both human health and environment. The study was designated to determine, for the first time, the values of ²³⁸U, ²³²Th and ⁴⁰K in nine different dyes employed in the textile industry using gamma spectrometry with a Hyper Pure Germanium (HPGe) detector. The mean activity concentrations of ²³⁸U, ²³²Th and ⁴⁰K were 29.37?±?4.48, 1.15?±?0.13 and 565?±?4 Bq/kg, respectively. The calculated radium equivalents for all samples were lower than the maximum admissible value (370 Bq/kg). The absorbed dose rates due to the natural radioactivity of the investigated samples ranged from 2.94?±?0.05 to 166?±?3 nGy/h. So, the absorbed dose rates for all samples of textile dyes were lower than the international recommended value (55 nGy/h) except the yellow dye (166?±?3 nGy/h), which recorded a significant radiological hazard. The external hazard index was also calculated. Conclusively, the results have indicated that the textile dyes may possess a measurable amount of radioactivity that should be taken into account. Therefore, safety rules and precautions should be applied for dyes used in the textile industry and for people working in this field.     

Radon survey and soil gamma doses in primary schools of Batman,Turkey

A survey was conducted to evaluate levels of indoor radon and gamma doses in 42 primary schools located in Batman, southeastern Anatolia, Turkey. Indoor radon measurements were carried out using CR-39 solid-state nuclear track detector-based radon dosimeters. The overall mean annual ²²²Rn activity in the surveyed area was found to be 49 Bq m^?3 (equivalent to an annual effective dose of 0.25 mSv). However, in one of the districts (Besiri) the maximum radon value turned out to be 307 Bq m^?3. The estimated annual effective doses are less than the recommended action level (3–10 mSv). It is found that the radon concentration decreases with increasing floor number. The concentrations of natural and artificial radioisotopes were determined using gamma-ray spectroscopy for soil samples collected in close vicinity of the studied schools. The mean gamma activity concentrations in the soil samples were 31, 25, 329 and 12 Bq kg^?1 for ²²⁶Ra, ²³²Th, ⁴⁰K and ¹³⁷Cs, respectively. The radiological parameters such as the absorbed dose rate in air and the annual effective dose equivalent were calculated. These radiological parameters were evaluated and compared with the internationally recommended values.     

Effect of salinity on the concentrations of radioisotopes in the aquatic environment of a hypersaline coastal lagoon

Research of the effect of salinity on the fate of radionuclides has been focused on seas or estuarine systems while there is almost no information on marine environments with a salinity higher than that of sea water. The hypersaline Bardawil lagoon is a concentration basin, with evaporation exceeding precipitation. This study presents the characteristics of some environmental factors including salinity and their influence on the distribution of natural and artificial radionuclides in different compartments of the lagoon. The concentrations of ²³⁸U, ²³⁴Th, ²²⁸Ra and ¹³⁷Cs in sediments show some degree of dependency on the water's salinity. Migration of these radionuclides in the lagoon's sediments must take place from high salinity to low-salinity regions. Cluster analysis revealed the data structure for sediment by separating ¹³⁷Cs and ⁴⁰K from ²³²Th, ²²⁶Ra, and ²³⁴Th and for sand by separating ⁴⁰K from the other radioisotopes.