Determination of radon concentrations and physicochemical parameters of non-alcoholic carbonated beverages consumed in Türkiye and assessment of radiological health risk.

The strategy for controlling the existence of radionuclides in drinking water depends upon an individual dose criterion (IDC) of 0.1 mSv/y, which represents a very low level of risk that is not expected to cause any identified adverse health effects. Radon gas, considered a carcinogenic radionuclide, can dissolve and accumulate in drinking water. Non-alcoholic carbonated beverages (NACBs), which mainly contain drinking water, phosphoric acid, citric acid, caffeine, and sugar, represent one of the most consumed groups worldwide and in Türkiye. In this study, the radon activity concentration and some physicochemical characteristics of 45 NACB samples from 24 most preferred commercial brands in Türkiye were determined to assess the radiological health risk associated with the ingestion of these samples. Radon activity concentrations measured in NACB samples using the AlphaGUARD radon analyzer ranged from 22.8 ± 0.7 to 54.9 ± 1.7 mBq/L. The pH, conductivity, total dissolved solids, and brix values in NACB samples ranged from 2.31 to 7.29, 401 to 3281 µSv/cm, 355 to 2453 mg/L, and 0.10 to 12.95%, respectively. Total (ingestion and inhalation) annual effective doses and the corresponding excess lifetime cancer risks estimated for adults to assess the radiological health risk are significantly below the IDC and advised safety limit (10-3), respectively.

Evaluation of radiological health risk caused by the use of fly ash in cement and concrete production and its storage.

As a result of firing pulverized coal in thermal power plants, enormous amounts of fly ash (FA) are produced as industrial waste. The release into the atmosphere and storage of this industrial waste remains one of the major environmental problems that threaten human health by contributing to air, water, and soil pollution. The recovery and reuse of FA in the construction industry is the only economic solution to the existing problem. In this study, the potential radiological risk caused by the usage of FA in concrete and cement production as a main component and its storage in landfill sites was evaluated for people and works by estimating radiological parameters (activity concentration and alpha index, annual effective doses, and the corresponding excess lifetime cancer risks) based on activity concentrations of terrestrial radionuclides in FA. Also, the radiological risk to the workers working in the FA landfill site was evaluated using the Residual Radioactivity Onsite 7.2 code. The average activity concentrations of terrestrial radionuclides in FA samples from the Tunçbilek lignite coal-fired thermal power plant at Kütahya province of Turkey were measured as 417, 156 and 454 Bq kg-1 for 226Ra, 232Th and 40K, respectively. When using up to 35% by mass of FA in cement and concrete, the average values of the radiological parameters revealed that they were within the recommended safety limits. However, code estimations showed that a regular worker in FA storage would be exposed to a total effective dose rate greater than 3 mSv y-1.

Assessment of internal radiation exposure caused by radon in commercially bottled spring waters consumed in Turkey.

The variation of dissolved radon levels in water supplies remains of interest since radon ingested through drinking water can give considerable radiation to the lining of the stomach. This study aims to determine the radon concentration levels in bottled spring drinking water (BSW) brands commercially sold in Turkey using a radon gas monitor and to assess the internal radiation exposure caused by the ingestion and inhalation of radon. The activity concentrations of radon analyzed in 77 BSW brands varied from 7.1±0.8 to 28.7±2.7 mBq/L with an average of 15.7±5.1 mBq/L. The total annual effective dose was estimated to assess the radiological risk for three age groups in four different scenarios based on annual drinking water intake. All estimated dose values are well below the recommended reference dose of 100 µSv for drinking water. Therefore, radon gas in the investigated BSW samples poses no significant radiological risk to the public.

Evaluation of radiological health risk due to ingestion and inhalation of radon in commercial packaged fruit juices consumed in Turkey.

Fruit juices (FJs) are among the most popular beverages frequently preferred by consumers, believing FJs contain the nutritional values, minerals, phytochemicals, vitamins, and antioxidants necessary for a healthy life. However, FJs may contain natural radionuclides such as radon (222Rn), which originates from the fruit and water utilized in their production, at levels that may pose a health risk to people. Inhalation and ingestion of 222Rn gas increases the risk of lung and stomach cancer. In this study, commercially packaged FJs from the seventeen most popular brands consumed in Turkey were analyzed for physicochemical properties and 222Rn activity concentrations to evaluate the radiological health risk. The values of pH, brix and 222Rn activity concentrations in FJ samples varied from 2.68 to 4.28, 2.50 to 14.30%, 9.6 ± 1.1 to 25.2 ± 2.5 mBq/L, respectively. The radiological health risk caused by internal exposure was evaluated for children and adults by estimating the ingestion and inhalation annual effective dose. The average values of the total annual effective dose for children and adults were found as 0.039 µSv and 0.056 µSv, respectively, which are much lower than the recommended dose of 100 µSv for drinking water.

Assessment of the Levels of Potentially Toxic Elements Contained in Natural Bentonites Collected from Quarries in Turkey.

Potentially toxic elements (PTEs) are an important type of pollutant, causing constant and far-reaching concerns around the world due to their increase in the mining process. Bentonite formed by the alteration of glass-rich volcanic rocks is a smectite clay consisting mostly of montmorillonite. Bentonite is an important mineral used in a wide range of applications in many fields such as oil and gas, agriculture, food, pharmacological, cosmetic, and construction industries due to its unique qualities. Given the widespread distribution of bentonite in nature and its use in a wide variety of consumer products, it is inevitable that the general population will be exposed to PTEs contained in bentonites. In this study, concentrations of PTEs in 69 bentonite samples collected from quarries located in different geographical regions of Turkey were analyzed by an energy-dispersive X-ray fluorescence spectrometric method. The average concentrations of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Zr, and Pb in bentonite samples were found to be 3510, 95, 129, 741, 30,569, 67, 168, 25, 62, 9, 173, and 28 mg/kg dry weight, respectively. Results of the enrichment factor relating to Earth's crust average indicated moderate enrichment with Cr, Ni, and Pb and significant enrichment with Co and As.

Heavy metal contamination and health risk evaluation of chestnut (Castanea sativa Miller) consumed in Turkey.

This study was performed to determine heavy metals and metalloids in twenty-eight chestnut (Castanea sativa Miller) samples consumed in Turkey by inductively coupled plasma optical emission spectrometry and evaluate health risks for humans through the consumption of chestnut samples. The concentrations of Cd, Cr, Co, Cu, Fe, Pb, Mn, Ni and Zn analyzed in chestnut samples varied from 537 to 635, 608 to 5333, 347 to 972, 207 to 8619, 12,739 to 86,310, 278 to 7549, 8676 to 67,622, 1068 to 18,661 and 3625 to 12,876 µg/kg (dry weight), respectively. The concentrations of Cd and Pb were above the maximum limits determined by the Turkish Food Codex. Healthy risks caused by the heavy metals in the consumed chestnut samples were evaluated by estimating the average daily intake of metal, health risk index (HRI), and total HRI. These results revealed that there is no possible health risk to consumers due to the intake of chestnut samples studied under the current consumption rate.

Radiological assessment of urban soil samples in the residents of a central Anatolian volcanic province, Turkey.

The concentration of natural and anthropogenic radionuclides, emanation fraction (EF), and mass (χM) and area (χA) exhalation rate of 222Rn in urban soil samples collected from dwelling areas in Nevsehir city located in a region known as the central Anatolian volcanic province of Turkey were determined using gamma-ray spectroscopy. The average activity concentrations of 226Ra, 228Ra, 40K and 137Cs were measured as 60.2 ± 3.8, 50.1 ± 2.8, 631.0 ± 29.7 and 5.5 ± 0.4 Bq/kg, respectively. The average concentration of 222Rn in soil and air was estimated as 27 kBq/m3 and 84 Bq/m3, respectively. The average values of EF, χM and χA were found as 20%, 25.4 µBq/kg⋅s and 20.2 mBq/m2⋅s, respectively. The average values of outdoor absorbed gamma dose rate, external and internal annual effective dose and lifetime cancer risk estimated for radiological assessment were found as 85 nGy/h, 104 µSv/y, 797 µSv/y and 4.1 × 10-4, respectively.

Evaluation of terrestrial radionuclide levels and concomitant radiological risks of bentonites used in many industries.

Bentonite is a soft, porous, easily shaped, and absorbent material rich in aluminum, sodium, and potassium. Bentonite is a mineral widely utilized as drilling mud, ore pelletizing, absorbent/adsorbent, bleaching agent, water impedance, coating, and raw material in various industries. In this study, radiometric measurements of 90 bentonite samples collected from 21 quarries in Turkey were performed using gamma-ray spectrometry. The radiological hazards caused by indoor exposure to adults due to the utilization of bentonites as raw materials in the construction industry and outdoor external exposures to quarry workers were evaluated by estimating the activity concentration index, annual effective doses, and lifetime cancer risk. The average activity concentrations of 226Ra, 232Th and 40K measured in bentonite samples were found as (50 ± 5) Bq/kg, (76 ± 4) Bq/kg and (373 ± 19) Bq/kg, respectively. The evaluation results reveal that the bentonites examined could be safely utilized as raw materials.

Potentially toxic element contamination and health risk assessment in bottled mineral waters consumed in Turkey.

This study aimed to evaluate the human health risk posed by potentially toxic elements (PTEs) in 59 bottled mineral water (BMW) samples of 25 different brands marketed in Turkey. The concentrations of Ag, Al, As, Cd, Cr, Co, Cu, Fe, Mn, Ni, and Pb in the BMW samples were analyzed using an ICP-OES and compared with maximum allowable concentrations (MACs). A higher concentration of As than MAC was detected in five BMW samples. The concentrations of Cd, Pb, Cr, Ni, and Al in the majority of BMW samples are higher than the MACs. The human health risk was evaluated for adults estimating non-carcinogenic risk index (HI), incremental lifetime cancer risk (ILCR) and total cancer risk (TCR). All HI values estimated for PTEs in BMW samples are less than one, except for one sample. ILCR values for Cd in approximately half of the BMW samples are above the upper limit.

Natural Radionuclides in Bottled Mineral Waters Consumed in Turkey and Their Contribution to Radiation Dose.

Bottled natural mineral water (BMW) consumption in Turkey is increasing every year. Depending on the local geology from which the water is extracted, BMW could be enhanced with natural radionuclides. In this study, the activity concentrations of natural radionuclides in 58 BMW samples of 25 different brands marketed in Turkey were measured using a γ-ray spectrometer with high-purity germanium (HPGe) detector. The average activity concentrations of 226Ra, 228Ra, and 40K in BMW samples were found as 0.4, 0.5, and 4.3 Bq/L, respectively. The activity concentrations of 228Ra exceeded the WHO-recommended maximum permissible limit of 0.1 Bq/L for drinking water. The annual effective dose (AED) and excess lifetime cancer risk (LCR) caused by the ingestion of each BMW sample were estimated for adults to assess radiological risks using two different scenarios based on BMW consumption rates (150 and 13 L/y). All estimated total AEDs, except for two samples, were below the guidance dose level of 100 µSv/y recommended by the World Health Organization (WHO) and Turkish regulations for drinking water. For all BMW brands, 228Ra was found as the main contributor to the AEDs. The LCR values were lower than the acceptable value of 10-3 for radiological risks.

Assessment of the Enrichment of Heavy Metals in Coal and Its Combustion Residues.

Coal-fired thermal power plants remain one of the main sources of electricity generation in Turkey. Combustion of coal creates coal ash and slag, which are often stored in landfills located near residential and agricultural fields, increasing the potential for high environmental contamination and health risks. This study investigates the content and enrichment factor (EF) of heavy metals in pulverized lignite coal and its combustion residues from the Kangal lignite coal-fired thermal power plant situated in the Central Anatolian Region of Turkey. The concentration of heavy metals (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Zr, Cd, Hg, and Pb) in lignite coal, slag, and fly ash samples were analyzed using an energy dispersive X-ray fluorescence technique. The concentration of Fe is highest while Hg concentration is lowest in the samples. The concentrations of heavy metals are higher in slag and fly ash samples than in lignite coal. Average values of EF (related to Earth's crust average) revealed that extreme enrichment has been shown by arsenic and mercury in lignite coal and fly ash samples while very high enrichment has been shown in slag samples.

Evaluation of natural radioactivity levels and potential radiological hazards of common building materials utilized in Mediterranean region, Turkey.

Radiometric measurement of building materials is very important to assess the internal and external exposure caused by the ionizing radiation emitted from terrestrial radionuclides in building materials. The activity concentrations of 226Ra, 232Th, and 40K in fifty-eight samples of fifteen different structural and covering building materials commonly used in Osmaniye province located in the Mediterranean region of Turkey were measured by using gamma-ray spectroscopy. The activity concentrations of 226Ra, 232Th, and 40K varied from 2.5 ± 0.1 (marble) to 145.7 ± 4.4 (clay brick), 1.3 ± 0.1 (marble) to 154.3 ± 4.1 (marble), and 8.6 ± 0.2 (sand) to 1044.1 ± 70.3 (granite), respectively. Radiological parameters (activity concentration index, alpha index, indoor absorbed gamma dose rate and the corresponding annual effective dose rate, and excess lifetime cancer risk) were estimated to evaluate the health hazards associated with these building materials. Since the estimated values of these parameters are within the recommended safety limits or criteria values, the use of the studied building materials in the construction of dwellings can be considered to be safe for the residents of the region.

Measurement of the terrestrial and anthropogenic radionuclide concentrations in Bafra Kizilirmak delta (bird sanctuary) in Turkey.

In this study, the activity concentrations of terrestrial and anthropogenic radionuclides in the soil samples collected from Bafra Kizilirmak Delta were measured by using gamma spectrometry with an NaI(Tl) detector. The average values of activity concentrations of (238)U, (232)Th and (40)K were found to be 37.2±2.8, 33.7±3.1 and 413.0±59.8 Bq kg(-1), respectively. (137)Cs was also measured in some samples. It has a mean value of 13.8±1.0 Bq kg(-1). From the activity concentrations, the absorbed gamma dose rates in outdoor and the corresponding annual effective dose rates and external hazard index (Hex) were estimated.

Natural radioactivity, radon exhalation rates and indoor radon concentration of some granite samples used as construction material in Turkey.

It is very important to determine the levels of the natural radioactivity in construction materials and radon exhalation rate from these materials for assessing potential exposure risks for the residents. The present study deals with 22 different granite samples employed as decoration stones in constructions in Turkey. The natural radioactivity in granite samples was measured by gamma-ray spectrometry with an HPGe detector. The activity concentrations of (226)Ra, (232)Th and (40)K were found to be in the range of 10-187, 16-354 and 104-1630 Bq kg(-1), respectively. The radon surface exhalation rate and the radon mass exhalation rate estimated from the measured values of (226)Ra content and material properties varied from 1.3 to 24.8 Bq m(-2) h(-1) with a mean of 10.5±1.5 Bq m(-2) h(-1) and 0.03-0.64 Bq kg(-1) h(-1) with a mean of 0.27±0.04 Bq kg(-1) h(-1), respectively. Radon concentrations in the room caused from granite samples estimated using a mass balance equation varied from 23 to 461 Bq m(-3) with a mean of 196±27 Bq m(-3). Also the gamma index (Iγ), external indoor annual effective dose (Eγ) and annual effective dose due to the indoor radon exposure (ERn) were estimated as the average value of 1.1±0.1, 0.16±0.02 mSv and 5.0±0.7 mSv, respectively, for the granite samples.

Assessment of the radiological impacts of utilizing coal combustion fly ash as main constituent in the production of cement.

The purpose of this study is to assess potential radiological impacts of utilizing pulverized fly ash (PFA) as a constituent in ordinary Portland cement. For this purpose, the activity concentrations of (226)Ra, (232)Th, and (40)K in samples of PFA and Portland cement containing 15%, 20%, and 25% by mass PFA were measured using gamma-ray spectrometry with HPGe detector. The mean activity concentrations of (226)Ra, (232)Th, and (40)K were found as 366.6, 113.7, and 460.2 Bq kg( - 1), 94.2, 25.9, and 215.3 Bq kg( - 1), 113.7, 34.3, and 238.3 Bq kg( - 1), and 124.2, 41.8, and 279.3 Bq kg( - 1) for the examined samples of PFA, Portland cement with 15%, 20%, and 25% by mass PFA, respectively. Radiological parameters such as radium equivalent activity, external exposure index (activity concentration index), internal dose index (alpha index), indoor absorbed gamma dose rate, and the corresponding the annually effective dose were assessed for Portland cement samples containing three percentages (15%, 20%, and 25%) by mass PFA. The results of assessment show that all Portland cement samples are within the safe limits recommended for building materials for dwellings.

Radioactivity levels of limestone and gypsum used as building raw materials in Turkey and estimation of exposure doses.

The natural radionuclide contents of limestone and gypsum samples used as building raw materials in Turkey were measured by means of gamma spectrometer system with HPGe detector. The measured activity concentrations of (226)Ra, (232)Th and (40)K radionuclide were compared with the reported data from other countries. Radium equivalent activity and internal hazard index, absorbed gamma dose rate in indoor due to the external exposure and corresponding annual effective dose were determined to estimate the exposure risk arising due to the use of these raw materials. This study has shown that examined gypsum and limestone raw materials do not pose any excess radiological health problem and are safe for use in the construction of buildings.

Radiological impacts of the usability of clay and kaolin as raw material in manufacturing of structural building materials in Turkey.

The aim of the present study is to measure the natural radioactivity due to the presence of radionuclides in clay and kaolin, used widely as raw materials in ceramics, bricks and cement industries, and to assess the possible radiological hazards associated with these raw materials. The activity concentrations of natural radionuclides (226)Ra, (232)Th and (40)K in 50 samples collected from different quarries were measured by means of gamma-ray spectrometry with an HPGe detector. The mean values of the measured activity concentrations of (226)Ra, (232)Th and (40)K for clay samples were found to be 39.3 +/- 22.7 Bq kg(-1), 49.6 +/- 27.9 Bq kg(-1) and 569.5 +/- 181.0 Bq kg(-1), and for kaolin samples 82.0 +/- 37.3 Bq kg(-1), 94.8 +/- 49.2 Bq kg(-1) and 463.6 +/- 544.9 Bq kg(-1), respectively. These levels are comparable to those appearing in clays of European countries. The radium equivalent activity and the external (gamma) and internal (alpha) hazard indices were calculated to assess the potential radiological hazard. The calculated gamma and alpha indices varied from 0.19 to 1.17 and from 0.04 to 0.47 for clay samples and from 0.36 to 1.75 and from 0.08 to 0.63, respectively. The mean value of the gamma index for the clay samples (0.57 +/- 0.24) is slightly above the criterion of 0.5 corresponding to an annual effective dose of 0.3 mSv, while the mean value of the gamma index for the kaolin samples (0.90 +/- 0.49) is below the criterion of unity corresponding to an annual effective dose of 1 mSv. The calculated alpha index values for all samples are below the recommended upper level.

Determination of specific activity of (226)Ra, (232)Th and (40)K for assessment of radiation hazards from Turkish pumice samples.

The specific activity of (226)Ra, (232)Th and (40)K in 52 Turkish pumice samples collected from 11 geographical areas located in Central Anatolia, Eastern Anatolia, Mediterranean and Aegean regions was determined by gamma-ray spectrometry with a high-purity germanium (HPGe) detector. The specific activity of (226)Ra, (232)Th and (40)K ranged from 12.7+/-0.5 to 256.2+/-9.1Bqkg(-1) with a mean of 89.1+/-65.2Bqkg(-1), 12.3+/-1.0 to 237.9+/-12.2Bqkg(-1) with a mean of 87.0+/-61.4Bqkg(-1) and 300.1+/-5.5 to 1899.0+/-30.8Bqkg(-1) with a mean of 1211.9+/-419.8Bqkg(-1), respectively. Elemental concentrations were determined for U (from 1.0 to 20.7ppm with a mean of 7.2+/-5.3ppm), Th (from 3.0 to 58.6ppm with a mean of 21.4+/-15.1ppm) and K (from 1.0 to 6.1% with a mean of 3.9+/-1.3%). The radium equivalent activity (Ra(eq)), the activity index, the emanation coefficient, the (222)Rn mass exhalation rate, the indoor absorbed dose rate and the effective dose rate were estimated for the radiation hazard of the natural radioactivity in all samples. The calculated mean Ra(eq) value was 306.6+/-177.7Bqkg(-1) (54.6+/-5.5 to 737.6+/-49.0Bqkg(-1)) for all pumice samples. This value is lower than the recommended limit value of 370Bqkg(-1) for building raws and products. The emanation coefficient and the (222)Rn mass exhalation rate of all samples ranged from 29.4 to 42.9% with a mean of 36.2% and from 11.0 to 196.4microBqkg(-1)s(-1) with a mean of 73.5microBqkg(-1)s(-1), respectively. The mean indoor absorbed dose rate and the corresponding mean effective dose rate were 274.6+/-153.6nGyh(-1) (50.4-644.6nGyh(-1)) and 1.35+/-0.75mSvy(-1) (0.24-3.16mSvy(-1)), respectively. For all pumice samples the mean indoor absorbed dose rate is about three times higher than the population-weighted average of 84nGyh(-1), while the mean effective dose rate values except for PUM 05, PUM 06, PUM 10 and PUM 15 exceed the dose criterion of 1mSvy(-1).

Radioactivity levels in some wild edible mushroom species in Turkey.

Eleven different wild-growing edible mushroom species collected from various regions of Turkey were analysed for their content of 137Cs, 40K, 226Ra and 232Th using a high-resolution gamma-ray spectrometry. Specific activities of 226Ra and 232Th were generally below detection limits. The specific activities of 137Cs and 40K ranged from 2.4+/-0.3 to 109.0+/-7.3 Bq kg-1 with a mean of 28.4+/-27.2 Bq kg-1 (dry matter) and 715.5+/-50.1 to 1779.0+/-163.7 Bq kg-1 with a mean of 1150.8+/-315.2 Bq kg-1 (dry matter), respectively. The mean annual effective dose of 137Cs and 40K through mushrooms were estimated to be (7.0+/-6.0)x10(-3) microSv and 0.13+/-0.03 microSv, respectively. The overall intake of 137Cs is quite low and no significant contamination was found in collected mushroom species. The highest contents of 137Cs and 40K among the analysed mushrooms were in Morchella esculenta and Stropharia coronilla, respectively.