Nuclear power plant biological complications on marine biota from a probabilistic accident - A case study.

An accident at the Barakah Nuclear Power Plant (BNPP) would result in a significant radionuclide release into the semi-closed marine environment. In this research, the released radionuclide distribution pattern and dose rate in the Persian/Arabian (Gulf) were calculated using a combined hydrodynamic/radiobiological model. Simulations of the dispersion of artificial radionuclide concentrations were conducted using a HYSPLIT model. To assess prospective hazards in case of an incident, environmental risk from ionizing contaminants: assessment and management (ERICA) tools were used. Using the Fukushima nuclear power accident as a model, the scenario source term profile was developed. The volumetric concentrations levels of pollutants ranged between 1 × 104 mBq m-3 to 1 × 1010 mBq m-3 in the radius of 200 km after 48 h. Based on the dose rates of the various marine biotas, Polychaete worms, and Pelagic fish, they had the highest and lowest dose contribution.

Radioactivity concentration levels and potential radiotoxicity risk assessment of aquatic superfoods case study of algae supplements.

It has been found that algae have a variety of health benefits, although investigations showed that they contain radiotoxic elements, including 226Ra, 232Th, 40K, and 137Cs, which may affect human health. This study is connected to activity concentration measurements of the above radionuclides in the algae supplements available in the Middle East markets. The annual effective radiation doses of measured radionuclides in analyzed algal supplements have been calculated. The highest values of annual effective doses have been estimated for 226Ra in Ecklonia (13.39 µSv/y) and for 232Th in Red Marine Algae (11.80 µSv/y), both from South Korea. In algal "superfoods", the effective dose of 137Cs is not significantly affected by the Fukushima Nuclear Power Plant. Based on these results, it can be concluded that the activity levels of radionuclides are low, the naturally occurring radionuclides provide the most effective doses, and algae supplements can be considered safe.

The distribution of radiotoxic 137Cs concentrations in seaweed and mussel species in the Mediterranean Sea.

A study was conducted to determine the 137Cs activity concentrations in various seaweed and mussel samples from the North East Mediterranean Sea, including the brown algae (Dictyota dichotoma) and oarweed (Laminaria digitata), and mussel species (Haliotis asinina, Mytilus edulis and Mytilus galloprovinciali). The 137Cs activity concentration in seaweed species exhibited varying levels, ranging from 84.20 ± 1.82 to 236.05 ± 5.72 mBq kg-1 fresh weight (fw) for oarweed, and 106.29 ± 2.26 to 252.38 ± 6.04 mBq kg-1 fw for brown algae. The 137Cs value in mussel species were between 12.94 ± 0.51-101.84 ± 1.35 mBq kg-1 fw for M. galloprovincialis, 15.49 ± 0.58-71.52 ± 1.16 mBq kg-1 fw for M. edulis, and 10.36 ± 0.11-69.13 ± 1.34 mBq kg-1 fw for H. asinine. When comparing the 137Cs concentration in seaweed and mussel species, the average concentration in seaweeds was approximately four times higher than that in mussels. This significant difference in radioisotope concentration highlights the potential for higher bioaccumulation of 137Cs in seaweeds compared to mussels.

Radiotoxic 210Po concentration in the Mediterranean Sea sediment and radiation risk assessment of biota.

This research presents the levels and distribution of 210Po in different sediments of the northeastern coast of the Mediterranean Sea. The 210Po activity concentrations were measured using an alpha spectroscopy system. The activity concentrations of 210Po in the sediment samples were in the range between 20.5 ± 0.7 and 92.8 ± 1.6 Bq kg-1 dw with an average of 48.2 ± 1.4 Bq kg-1 dw. The microorganism-enriched sampling sites (bedrock sites) indicated low 210Po concentration than sandy coastal sites. As a result of these measurements, the RESidual RADioactivity (RESRAD) biota code was applied to calculate the tissue concentration rate (CR), internal dose rate, external dose rate, and total dose rate of the exposed tissues. The total dose rates of aquatic animals were found higher than that of riparian animals. The 210Po sediment resource doses to aquatic and riparian animals were found less than the dose level recommended by International Commission on Radiological Protection (ICRP).

Radioactivity concentration and radiological risk assessment of beach sand along the coastline in the Mediterranean Sea.

A radiological baseline survey was conducted using a calculation analysis to assess the 226Ra, 232Th, 40K, and 137Cs distribution in beach sand samples collected from the coastal areas of the Mediterranean Sea. An analysis of the activity concentration of selected radionuclides was conducted. No evidence of recent migration of radiocaesium was found through precipitation, as well as indirect pathways, such as ocean runoff. The activity concentration of 226Ra, 232Th, 40K and 137Cs in beach sands ranged from 12 ± 1 to 37 ± 4 Bq kg- 1 (mean of 26 ± 3 Bq kg- 1); 18 ± 2 to 71 ± 8 Bq kg- 1 (mean of 40 ± 5 Bq kg- 1); 411 ± 10 to 720 ± 16 Bq kg- 1 (mean of 572 ± 12 Bq kg- 1); and 0.8 ± 0.1 to 3.1 ± 0.6 Bq kg- 1 (mean of 1.9 ± 0.3 Bq kg- 1), respectively. The radiological risk assessment showed that in all cases the values were lower than those that endanger life and safe work.

Radiation risk assessment of coastal biota from a quasi-Fukushima hypothetical accident in the Mediterranean Sea.

The occurrence of the February 6, 2023, earthquake in Turkey was the idea of this research to define a Fukushima-like accident scenario in the Akkuyu nuclear reactor and investigate its radiation effects on the coastal organisms of the Mediterranean Sea. The concentration rate (CR), activity concentration in organisms, internal dose, external dose, and total dose rate were estimated using the ERICA Tool from 137Cs, 134Cs and 131I radionuclides. The minimum and maximum radiocesium CR were calculated at 0.063 Bq kg-1 fresh weight (f.w)/Bq kg-1 soil and 4.042 Bq kg-1 (f.w)/Bq kg-1 soil dry weight (d.w). Where this value for 131I ranged from 0.005 to 0.295 Bq kg-1 (f.w)/Bq kg-1 soil. For mammals-large and arthropods, we calculated the significant internal and external dose rates. All of the estimated dose rates were higher than the ICRP's derived consideration reference levels (10 µGy h-1).

Radiotoxic fission products and radiological effects in the Mediterranean Sea biota from a hypothetical accident in Akkuyu Nuclear Power Plant.

A combined hydrodynamic/radiobiological model was used to calculate the distribution and dose rate of significant radionuclides in the Mediterranean Sea marine organisms in the event of an accident at the Akkuyu Nuclear Power Plant (ANPP). The Hybrid single-particle Lagrangian integrated trajectory (HYSPLIT) model was applied to simulate the dispersion and deposition of artificial radionuclide concentrations. Environmental Risk from Ionising Contaminants: Assessment and Management (ERICA) tools were utilized to assess issues related to sea health and potential hazards in case of an accident. The scenario source term profile was derived from the Fukushima nuclear power accident. Volumetric concentrations and deposition levels of pollutants increased from 1 MBqm-3 to 1 × 103 MBqm-3 and from 1 × 10-1 MBqm-2 to 1 × 10-7 MBqm-2 after 48 h. In terms of dose rates to the various marine biotas, polychaete worms had the greatest overall dose rate and the highest contribution to total dose rates attributable to 137Cs radionuclide.

Bioaccumulation and risk assessment of radiocesium in the Northwest Pacific Ocean from Fukushima Dai-ichi Nuclear Power Plant accident.

To understand which biota are more exposed to radionuclides, the bioaccumulation and risk assessment of radiocesium (137Cs and 134Cs) release from FDNPP in the Northwest Pacific Ocean were analyzed using ERICA tools. The activity level was determined by the Japanese Nuclear Regulatory Authority (RNA) in 2013. The data were used as input to the ERICA Tool modeling software to evaluate the accumulation and dose of marine organisms. The highest and lowest accumulate concentration rate were observed in birds (4.78E+02 Bq kg-1/Bq L-1) and the Vascular plant (1.04E+01 Bq kg-1/Bq L-1), respectively. The total dose rate range for the 137Cs and 134Cs ranged between 7.39E-04 and 2.65E+00 µGy h-1 and 4.24E-05 and 2.91E-01 µGy h-1, respectively. There is no considerable risk to the marine biota in the research region since the cumulative dose rates of radiocesium to the chosen species were all less than 10 µGy h-1.

Distribution of natural and anthropogenic radionuclides and associated radiation indices in the Southwestern coastline of Caspian Sea.

The distribution pattern of natural radionuclides (226Ra, 232Th, and 40K) and anthropogenic radionuclide (137Cs) in surface sediment samples from the southwestern coastline of the Caspian Sea were determined to estimate the radiation hazard indices using a high-purity germanium HPGe gamma-ray detector. The activity concentrations of the sediment samples ranged from 22.5 ± 1.0 to 47.4 ± 2.2 Bq kg-1 dry weight (dw) for 226Ra, 6.5 ± 0.1 to 18.7 ± 0.7 Bq kg-1 dw for 232Th, 559.9 ± 30.9 to 233.2 ± 19.4 Bq kg-1 dw for 40K, and 0.9 MDL (minimum detection limit) to 2.7 ± 0.1 Bq kg-1 dw for 137Cs. Based on the measured values, radiological risk indices were estimated. The mean values for absorbed dose rate, ambient dose equivalent rate, and excess lifetime cancer risk, were calculated as 35.7 nGy h-1, 47.9 nSv h-1, and 0.2, respectively.

Radiological risk assessment of natural radionuclides in the marine ecosystem of the northwest Mediterranean Sea.

PURPOSE: This study aimed to assess the radiological risk of natural radionuclides (226Ra, 232Th, and 40K) to marine ecosystem biota. MATERIALS AND METHODS: The study site in this was the Mediterranean Sea, Cyprus. With the use of the RESRAD-BIOTA (RESidual RADioactivity BIOTA) code, the tissue concentration, external and internal dose rate of aquatic animals and riparian animals were estimated. RESULTS: The total tissue concentrations of the aquatic animals and riparian animals were simulated at 1.14 × 106 Bq/kg (water media) to 0 Bq/kg (sediment media), and 1.33 × 106 Bq/kg (water media) to 9.79 × 101 Bq/kg (sediment media), respectively. The total dose rate for aquatic animals and riparian animals was ranged from 1.94 × 10-2 to 0 Gray per day (Gy/d) and 1.46 × 10-2 to 7.40 × 10-7 Gy/d, respectively. CONCLUSIONS: Based on the risk assessment of this study, there is no significant impact due to organisms' exposure to natural radioactivity. Although, further consideration of the exposure levels is required due to the potential effects of protracted low-level ionizing radiation.

WINDCATCHER VENTILATION COMPUTATION AND INDOOR 222RN CONCENTRATION IN TRADITIONAL ADOBE HOUSES.

Radon-based radiation is a significant issue that can affect resident health as a contributory source of natural radiation from soil construction materials. This study investigates the effect of windcatchers on radon activity concentrations and radon exhalation rate from the soil surface in traditional adobe houses of Yazd, Iran. Radon concentrations were measured by passive detectors in 16 adobe houses. Computational fluid dynamics simulations were performed for different wind speed to calculate ventilation rate. The concentrations of 222Rn were in the ranges of 22 ± 1-117 ± 8 Bq m-3 with an average value of 50 ± 3 Bq m-3. The radon exhalation rates values were in the range of 8.3 ± 0.1 to 47.2 ± 0.5 Bq m-2 h-1. Radon concentration results in only one dwelling site were higher than the level recommended by the World Health Organization. The annual radon inhalation dose was found in seven sites higher than the worldwide average.

Trace element concentration and Al/Fe ratio in sediments of the South East Mediterranean Sea.

The heavy metals (HMs) concentration range, the metal/Al and metal/Fe value were determined in the sediment in order to evaluate the correlation coefficient of HMs at the regions of South East Mediterranean Sea, Cyprus. The results showed that the mean concentrations of the HMs in the sediment samples followed the order Al > Fe > Mn > Cr > Ni > Zn > Cu > Pb > As>Hg, respectively. The pollution indices of contamination factor (CF), geoaccumulation index (Igeo), enrichment factor (EF), and soil pollution index (SPI) were calculated. The Igeo, CF and EF values for Cu were obtained moderately to strongly polluted, moderate contamination and moderately severe enrichment, respectively. The remaining elements indicated unpolluted or low contamination results. Also, SPI indicated a low level of contamination for the all of the metals. The cluster analysis of data set indicates that the HMs are separated with 50% similarity in two categories of Al category (As, Pb, Cr, Ni) and Fe category (Mn, Zn, Cu, Hg).

Influences of COVID-19 pandemic lockdown on excess lifetime cancer risk value of natural radiation.

Abstract: This study focuses on the consequences of the COVID-19 pandemic on annual effective doses and excess lifetime cancer risk values due to ionizing radiation and radon which has been reported UNSCEAR 2000. The random data collection questionnaire method was applied to assess the indoor and outdoor occupancy factor for three age groups during the epidemic in Turkey. The results indicated age group C (Age > 65 y) has more influence from pandemic indoor and outdoor occupancy factor. As compared to before pandemic data in study area and global average exposure to natural radioactive sources.

Calculation of radium-223 and actinium-225 α-emitter radiopharmaceuticals dose rates in treatment of metastatic castration-resistant prostate cancer.

AIM OF STUDY: There is limited information regarding the α-emitter radiopharmaceuticals dose calculation used in the setting of men with prostate cancer (PCa). The present study investigates the α-emitter radiopharmaceuticals absorbed dose distribution in the body organs. MATERIALS AND METHODS: The α-emitter radiopharmaceuticals dose coefficient and absorbed doses biokinetics distribution, which are used for the treatment of PCa in all over the world, were performed using the "Internal Dose Assessed by Computer" (IDAC-Dose 2.1) program. The results of absorbed dose distribution in any organ of the body, were compared in studied α-emitter radiopharmaceuticals. RESULTS: The absorbed dose value of 223Ra radiopharmaceutical in the prostate organ was evaluated 9.47E-9 Gy/Bq. The maximum and minimum absorbed doses due to biokinetics distribution of 223Ra were found in the thymus (9.53E-8 Gy/Bq) and eye lenses (1.30E-10 Gy/Bq) organs, respectively. Furthermore, the 225Ac absorbed dose in the prostate organ was obtained 1.91E-9 Gy/Bq, where this value is 1% of total body dose. While the absorbed dose distribution of 225Ac in body organs shows the highest concentration in the spleen (1.47E-8 Gy/Bq) and lowest in the eye lenses (7.93E-12 Gy/Bq). CONCLUSION: The absorbed dose in the body organs due to 223Ra and 225Ac α-emitter radiopharmaceuticals which are used in metastasized castration-resistant prostate cancer (mCRPC), calculated in this study. The results of this study will assist in evaluating and analyzing human body organ doses from application of 223Ra and 225Ac that used in mCRPC patients.

Effect of human body position on gamma radiation dose rate from granite stones.

The use of granite stones as building materials in homes or offices can result in the residents' long-term whole-body exposure to gamma radiation. Although the whole-body annual dose has been investigated in the literature, it is obvious that different human organs receive different equivalent dose due to different position respect to the walls and floor covered by granite stones. In this paper, the effect of distance from the walls and floor of a room on the equivalent dose is investigated by using MCNPX code. An "ORNL" phantom is simulated in three situations; standing (P1), sleeping one meter above the floor (P2) and sleeping on the floor (P3) and the equivalent dose in different organs is calculated. Excess lifetime cancer risk (ELCR) is calculated in the whole of the body for these three positions. By the results, the value of ELCR in the third position is more than the average world value (2.9 × 10-4). The results show the importance of considering body position in dose determination, especially in some organs such as the brain and eyes which are close to the granite stones in certain positions such as sleeping.

The anthropogenic radiotoxic element of 137Cs accumulate to biota in the Mediterranean Sea.

The abundance of 137Cs radionuclide in the Mediterranean Sea has limited study despite its environmental effects in seafood chains. For this purpose, the activity concentration of 137Cs in sediment and seawater have been determined using a high-resolution HPGe gamma-spectrometry system. The average activity concentrations in sediment and water were 14.16 Bq kg-1 and 1.74 mBq L-1, respectively. The results were used as input data of ERICA Tool modelling software to assess marine organisms' accumulation and dose. The highest and lowest accumulate activity concentration values were observed in birds (9.24E-01 Bq kg-1) and the Vascular plant (1.37E-02 Bq kg1), respectively. The total dose rate value was ranged between 1.94E-06 µGy h-1 (Phytoplankton) to 4.70E-03 µGy h-1 (Polychaete worm). The total dose rates of 137Cs to the selected organisms were all <0.001 µGy h-1, and there is no significant risk to marine biota in the study area.

Estimation of cancer risk due to radiation exposure for some daily consumption of foods.

AIMS: Considering the increasing concern about the cancer risk caused by environmental radiological effects related to the food consumption, the study was carried out evaluate the activity concentrations and cancer risk assessments of 226 Ra,232 Th, and 40 K in 72 food samples collected from different suppliers in Tehran Province of Iran. SUBJECTS AND METHODS: The specific activity concentration was determined by means of a high-resolution high-purity germanium gamma-spectroscopy system. The collected various sample groups were wheat, rice, meat, milk, and mushroom. RESULTS: The maximum concentration of 226 Ra and 232 Th was found in the wheat sample, equal to 0.7862 Bq/kg and 0.968 Bq/kg, respectively, whereas for 40 K, it was 598.35 Bq/kg in the milk sample. The annual effective dose rate ranged from 2.47 µSv/y in mushroom to 64.66 µSv/y in rice. The average excess lifetime cancer risk (ELCR) was varied from 1.60 × 10-5 for mushroom to 4.20 × 10-4 for milk, with the total ELCR value from main daily diets 1.37 × 10-3, which was a little more than the acceptable ELCR limit of 10-3. CONCLUSIONS: The ELCR due to five main daily diets was a little more than the acceptable ELCR limit of 10-3 for radiological risk in general.

Baseline levels of natural radionuclides concentration in sediments East coastline of North Cyprus.

In this study, surface sediment samples from the North Cyprus East coast of the Mediterranean Sea were collected to determine the concentrations of three main natural radionuclides (226Ra, 232Th, and 40K) using a high-resolution HPGe gamma-spectroscopy system. The activity concentrations of 226Ra, 232Th, and 40K in the selected sediment samples ranged from 11.5 to 31.6, 11.8 to 24.9, and 391.7 to 1014 Bq kg-1 dw (dry weight), respectively. The concentration distribution analysis showed that the kurtosis statistics parameter was negative, and the concentration distribution was less peaked than the normal curve. The mean activity concentrations of 40K (628.1 Bq kg-1) in the sediment samples was higher than the worldwide average (420 Bq kg-1) concentration. The radium equivalent activity, external hazard, internal hazard and gamma activity concentration indexes were calculated to assess the pollution and risk level of radionuclides. The radiological risk assessment indicated that observed values were below the threshold values.

Some physicochemical parameters and 226Ra concentration in groundwater samples of North Guilan, Iran.

The 226Ra concentration and some physicochemical parameters have been measured in thermal spring waters used for medical therapy and drinking purposes in the Astara basin of North Guilan, Iran. The radon emanation method was performed using the AB-5 photomultiplier tube to measure the 226Ra concentration in water samples. Also, the physicochemical parameters of the water were measured in situ using a portable multimeter-VWR multi. The average concentrations of 226Ra were ranged between 3.4 ± 0.06 to 38.2 ± 0.08 mBq l-1. For all samples, the 226Ra concentration values range is lower than the maximum admissible value recommended by the WHO report. The relation between the physicochemical parameters and 226Ra activity concentration of groundwater was assessed. The results indicate a significant correlation coefficient between 226Ra concentration and T, as well as acidity pH. Anomalously high 226Ra concentrations in groundwater are preferentially found in high temperate and electric conductivity along with the acidic environment.