210Po Activity Research Articles

Effect of gamma dose rate on the public from soil samples collected from industrial areas of Tamil Nadu.

The present work is the first and foremost radiological study of soil samples collected from industrial estates in Tamil Nadu. The magnetic susceptibility measurement revealed that 74.19% of the samples have medium %χFD, which denotes a commixture of coarser grains or the SP grains with a size of <0.005μm. The range of measured activities of 210Po and 210Pb were 3±0.3-38±2.6Bqkg-1 and 16±1.5-48±2.9Bqkg-1. The mean activity concentrations of 238U (33Bqkg-1) and 40K (467Bqkg-1) marginally exceeded the Indian recommended values of 28.67 and 400Bqkg-1, respectively, whereas 232Th (47Bqkg-1) did not exceed 63.83Bqkg-1. The 238U and 232Th are the significant contributors to the production of radiogenic heat in the study area. Pearson correlation analysis confirmed the prime role of 232Th in radiation hazards and the insignificant relation between magnetic minerals and natural radioactivity.

Türkiye'nin farklı kıyı bölgelerinden Çin şapkası, Patella caerulea (Linnaeus, 1758) ve deniz kestanesinde Paracentrotus lividus (Lamarck, 1816) polonyum-210 biyoakümülasyonunun mevsimsel olarak değerlendirilmesi

This study investigated the seasonal variations of polonium-210 (²¹⁰Po) activity concentrations in two marine invertebrate species: Mediterranean limpet (P. caerulea) and the sea urchin (P. lividus). Seasonal sample collection was conducted across three Aegean and Sea of Marmara coastal stations from December 2018 to October 2019. The stations included İzmir-Urla, Karaburun, and İstanbul Island-Kınalıada. To assess the size-dependent bioaccumulation of ²¹⁰Po, individuals were categorized into size groups. The activity concentrations in both species exhibited seasonal fluctuations, ranging from 4.9 ± 3.4 Bq kg⁻¹ dry weight to 28.0 ± 8.4 Bq kg⁻¹ dry weight in Mediterranean limpets and 8.7 ± 6.1 Bq kg⁻¹ dry weight to 58.0 ± 18.5 Bq kg⁻¹ dry weight in sea urchins. The highest ²¹⁰Po activity concentrations were consistently observed in spring across all sampling locations.

Evaluation of 210Po, 210Pb, and potentially toxic element concentrations in aquatic environments and polychaetes along the southeast coast of Chennai, Tamil Nadu: a baseline report

ABSTRACT The activity concentrations of radionuclides (210Po and 210Pb) and the concentrations of potentially toxic elements (PTEs) in water, sediment, and two polychaete species (Marphysa madrasi and Namalycastis jaya) collected from 12 stations, denoted as S1 to S12, along the coast of Tamil Nadu, Chennai, in southeast India has been investigated. The average activity concentrations of 210Po and 210Pb were 0.39 ± 0.01 mBq/L and 3.30 ± 0.06 mBq/L in water, and 0.80 ± 0.02 Bq/kg and 4.21 ± 0.19 Bq/kg in sediment, respectively. Marphysa madrasi exhibited higher 210Po and 210Pb activity concentrations (37.78 ± 0.43 Bq/kg and 17.25 ± 0.22 Bq/kg, respectively) compared to Namalycastis jaya (34.40 ± 0.42 Bq/kg and 15.91 ± 0.26 Bq/kg, respectively). Maximum activity concentrations for both radionuclides in water were observed at Kalpaakam (S11) and Nemmeli (S7), while maximum sediment activity concentrations were found at Nemmeli (S7). The elevated activity concentrations in polychaetes from Nemmeli (S7) likely reflect the significantly higher 210Po and 210Pb activity concentrations observed in sediments from this site when compared to other sites. Bioaccumulation values for 210Po and 210Pb averaged 6.89 × 101 and 4.20 for M. madrasi, and 6.17 × 101and 3.84 for N. jaya , respectively. Sediment PTE concentrations followed the order: Fe > Zn > Mn > Ni > Co > Cr > Pb > Cd > Cu. Risk assessment indicated alarming levels of PTE contamination in sediments, suggesting severe anthropogenic impacts. In contrast, average PTE concentrations in polychaetes followed the order: Fe > Cu > Zn > Mn> Cr > Ni > Co > Cd > Pb. Statistical analysis revealed strong and significant correlations (p < 0.05) between PTE concentrations in sediments and polychaetes. The present study offers baseline data for evaluatingthe levels of 210Po and 210Pb in water, sediment, and polychaetes in selected locations along Chennai, Tamil Nadu, India’s southeast coast. These findings lay the groundwork for further studies of polychaetes, specifically the ecological effects of PTEs and radionuclides on coastal creatures and biomagnification.

210Po and 210Pb Distributions Along the GEOTRACES Pacific Meridional Transect (GP15): Tracers of Scavenging and Particulate Organic Carbon (POC) Export

AbstractDistributions of the natural radionuclide 210Po and its grandparent 210Pb along the GP15 Pacific Meridional Transect provide information on scavenging rates of reactive chemical species throughout the water column and fluxes of particulate organic carbon (POC) from the primary production zone (PPZ). 210Pb is in excess of its grandparent 226Ra in the upper 400–700 m due to the atmospheric flux of 210Pb. Mid‐water 210Pb/226Ra activity ratios are close to radioactive equilibrium (1.0) north of ∼20°N, indicating slow scavenging, but deficiencies at stations near and south of the equator suggest more rapid scavenging associated with a “particle veil” located at the equator and hydrothermal processes at the East Pacific Rise. Scavenging of 210Pb and 210Po is evident in the bottom 500–1,000 m at most stations due to enhanced removal in the nepheloid layer. Deficits in the PPZ of 210Po (relative to 210Pb) and 210Pb (relative to 226Ra decay and the 210Pb atmospheric flux), together with POC concentrations and particulate 210Po and 210Pb activities, are used to calculate export fluxes of POC from the PPZ. 210Po‐derived POC fluxes on large (&gt;51 μm) particles range from 15.5 ± 1.3 mmol C/m2/d to 1.5 ± 0.2 mmol C/m2/d and are highest in the Subarctic North Pacific; 210Pb‐derived fluxes range from 6.7 ± 1.8 mmol C/m2/d to 0.2 ± 0.1 mmol C/m2/d. Both 210Po‐ and 210Pb‐derived POC fluxes are greater than those calculated using the 234Th proxy, possibly due to different integration times of the radionuclides, considering their different radioactive mean‐lives and scavenging mean residence times.

A new procedure to validate and optimize 210Po measurements in atmospheric aerosols

The exposure to air fine aerosols can cause health effects due to inhalations of alpha emitters such as 222Rn daughters. Lead-210 and 210Po are mainly associated to aerosols with median aerodynamic diameter lower than 1 μm. The 210Po is characterized by having a high radiotoxicity. The precise measurement of 210Po in surface air aerosols is usually quite complex due to the significant contribution of the 210Pb on their concentrations. Additionally, there is no possible means to manufacture a certified material to validate the measurements of 210Pb and 210Po concentrations in surface air aerosols. For these reasons, this study aims to develop a novel and comprehensive methodology to validate 210Po measurements in surface air aerosols by preparing in our laboratory “standard samples” with known activities of both 210Pb and 210Po. A detailed sensitivity analysis on the precision of 210Po concentration measurements has been carried out as a function of the involved variables such as sampling time, time elapsed between the sampling start and 210Po self-deposition and the 210Po/210Pb activity ratio in surface air aerosols. This study is necessary to find the optimum conditions for a precise measurement of 210Po in surface air aerosols. In addition, this methodology has been applied for the determination of 210Po concentrations in 30 samplings campaigns of atmospheric aerosols carried out at the El Carmen campus (Huelva province) from March 25th to July 15th, 2022. The results obtained for 210Pb and 210Po concentrations and atmospheric aerosol residence times (via 210Po/210Pb activity ratio) were consistent with other previous works.

Development of large-volume 130TeO2 bolometers for the CROSS 2β decay search experiment

We report on the development of thermal detectors based on large-size tellurium dioxide crystals (45 × 45 × 45 mm), containing tellurium enriched in 130Te to about 91%, for the CROSS double-beta decay experiment. A powder used for the crystals growth was additionally purified by the directional solidification method, resulting in the reduction of the concentration of impurities by a factor 10, to a few ppm of the total concentration of residual elements (the main impurity is Fe). The purest part of the ingot (the first ∼ 200 mm, about 80% of the total length of the cylindrical part of the ingot) was determined by scanning segregation profiles of impurities and used for the 130TeO2 powder production with no evidence of re-contamination. The crystal growth was verified with precursors produced from a powder with natural Te isotopic composition, and two small-size (20 × 20 × 10 mm) samples were tested at a sea-level laboratory showing high bolometric and spectrometric performance together with acceptable 210Po content (below 10 mBq/kg). This growth method was then applied for the production of six large cubic 130TeO2 crystals and 4 of them were taken randomly to be characterized at the Canfranc underground laboratory, in the CROSS-dedicated low-background cryogenic facility. Two 130TeO2 samples were coated with a thin, 𝒪(100 nm), metal film in form of Al layer (on 4 sides) or AlPd grid (on a single side) to investigate the possibility to tag surface events by pulse-shape discrimination. Similarly to the small natural precursors, large-volume 130TeO2 bolometers show high performance and even better internal purity (210Po activity ∼ 1 mBq/kg, while activities of 228Th and 226Ra are below 0.01 mBq/kg), satisfying requirements for the CROSS and, potentially, next-generation experiments.

Characteristics and radiological hazard assessment of 210Po activity level in Dotted gizzard shad (Konosirus punctatus) from Quang Ninh province, Northern Vietnam

The natural radionuclide 210Po accumulates readily in marine organisms and is a significant contributor to the radiological dose from consuming seafood. This study analyzed the 210Po activity in thirty specimens of Dotted gizzard shad, a common and commercially important species of Clupeiform fish distributed in Quang Ninh province, Vietnam. The measurements were taken using an alpha spectrometer to measure the radionuclide from various tissues collected from each fish specimen. The highest activities of 210Po were found in the liver and intestine, while the lowest activity was observed in muscle tissue. The trend of 210Po activity in the different tissues was muscle < skin < stomach < gill < bone < intestine < liver, with mean values of 15.1 ± 1.7, 39.6 ± 9.6, 51.2 ± 5.5, 58.2 ± 7.2, 62.2 ± 13.5, 241 ± 18.7, and 346 ± 30.5 Bq.kg−1, respectively. There was an insignificant correlation between 210Po activity in the muscle and the mass and size of the fish. The calculated annual effective dose for adults from consuming only the Dotted gizzard shad containing 210Po exceeded the recommendation value (1 mSv.y−1) for all tissues except muscle. The concern for exceeding ingestion doses applies primarily to consumers who choose to eat the organs, including the gastrointestinal tract, of Dotted gizzard shad, assuming an annual consumption of 27 kg.y−1 for each organ. Therefore, this study emphasizes that people should be advised not to consume the digestive organs of Dotted gizzard shad to avoid radiological risk.

Optimised solid-phase extraction of 211At: Activity balance of 211At, 210At and 210Po after wet chemistry target dissolution

Several studies have illustrated the significant increase in the production yield of cyclotron produced 211At by irradiating targets at higher beam energies, highlighting that this approach warrants consideration. Recently published data also confirms the importance of the 209Bi(α,x)210Po reaction in addition to the increasing 210At production at higher energies, stressing the importance of determining the total 210Po activity on irradiated targets and the validation of radiochemical separation of 210Po from astatine as an impurity.In this work, two experiments were performed: (i) the dissolution of irradiated Bi-targets to validate the calculated 211At, 210At and 210Po activities on target and (ii) the radiochemical separation of astatine by extraction chromatography to determine the activity balance of 211At, 210At and 210Po after target processing.The calculated 211At, 210At and 210Po activities were validated on targets irradiated at the Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark. 211At and 210At activities were determined by gamma spectrometry, whereas the 210Po activity was measured by liquid scintillation counting (LSC) after target dissolution with concentrated nitric acid. The activity balance during target processing and extraction chromatography was established using targets irradiated at Arronax, Nantes, France. Targets were characterised after the dissolution with an in-house developed dissolution unit. Dissolution yield, extraction yield and separation capability were assessed by determining 211At, 210At and 210Po activities at every step.The results show that more than 88% of the total 210Po activity in targets irradiated at ≈ 28.8 MeV is attributable to the direct production of 210Po. This amounts to about 53% at energies of 29.8 MeV. A maximal discrepancy of 21% was found when comparing the total measured activity to the total calculated 210Po. Activity balance calculations show a mean decay-corrected dissolution yield of 88.9% ± 9.5% and an extraction yield of 87.56% ± 11.4% (n = 5) of 211At/210At resulting in an overall yield of 77.8% ± 10.5% (n = 5). In addition, the radiochemical separability was confirmed by removing >95% of the previously formed 210Po before extraction.This work confirms the important underestimation of the total 210Po component on irradiated targets at 28.8 and 29.8 MeV when calculating solely from 210At measurements. In addition, the validation measurements indicate that calculations can be used to estimate the total 210Po activity.The experimental setup of target dissolution and extraction chromatography presented a very good yield. It allowed the safe isolation and management of 210Po, leaving 210At as the only source for future ingrowth of 210Po. This finding is an important step in moving beyond the conventional approach of irradiating Bi-targets at limited incident energies.

Characteristics and radiological hazard assessment of 210Po in tilapia (Oreochromis niloticus) in Vietnam.

210Po is one of the most toxic natural radionuclides. This isotope's characteristics and radiological hazard assessment have been concerned in different objects. In this study, the 210Po activities were determined in different tilapia organs/parts of 20 sample groups by alpha spectrometry. The 210Po activities in muscle, bone, intestine organs, and stomach contents unevenly distributed with a wide range from 0.5 ± 0.2 to 2.8 ± 0.4 and 1.4 ± 0.2Bq·kg-1 wet.wt on average, from 0.6 ± 0.3 to 6.3 ± 0.7 and 3.5 ± 0.4Bq·kg-1 wet.wt on average, from 46.3 ± 2.9 to 263 ± 9.7 and 115 ± 6Bq·kg-1 wet.wt on average, and 20.9 ± 1.2 to 800 ± 29 and 197 ± 9Bq·kg-1 wet.wt on average, respectively. The average 210Po activities in different parts of tilapia trend in order of CMuscle < CBone < CIntestine < CStomach contents. Insignificant correlations were observed between 210Po activities in tilapia organs with their total fish mass. The result could depend on feeding types, diet, different nutrient levels, metabolism, and excretion of 210Po in different ages. The concentration ratios (CRs) of tilapia muscle and bone organs were recorded with low values, while it was far greater than the CRs for the intestine organ. Annual committed effective doses contributing from 210Po concentration due to tilapia fish consumption were within the allowable limits for muscle and bone organs, while those values for intestine organs were far higher than the allowable limit value (assuming similar amount consumption of 30kg·year-1 for each organ). The Erica tool was used to estimate the dose and risk to tilapia from 210Po exposure. Based on the calculated results, it can be seen that there was insignificant concern for tilapia due to ionizing radiation in the study area.

Assessment of the mobility of potentially toxic trace elements (PTEs) and radionuclides released in soils stabilized with mixtures of bentonite-lime-phosphogypsum.

Phosphogypsum (PG) is a solid by-product of the phosphate industry, rich in contaminants and produced in large quantities. Raw materials and stabilized specimens, consisting of bentonite-lime-PG mixtures, were characterized by mineralogical, microstructural, chemical, alpha-particle, and gamma-ray spectrometry analysis before hydration and after hardening. Compressive strength and leaching tests were performed on hardened specimens. The physicochemical parameters and chemical composition of leachates from raw materials and hardened specimens were determined. PG contains high concentrations of natural radionuclides, specially from U series. Uranium-238 activities are double in PG than the worldwide average for soil values. The mobility of PTEs from PG is Cd (2.43%), Zn (2.36%), Ni (2.07%), Cu (1.04%), Pb (0.25%), and As (0.21%). Cadmium is the cation most easily released by PG in water with a concentration 0.0316mgkg-1. When PG is added to bentonite-lime mixture, cadmium is no longer released. The radionuclide 238,234U and 210Po predominates in the leachates of PG. However, the activity of 210Po becomes negligible in the leachates of bentonite-lime-PG mixtures. The addition of PG to bentonite-lime mixtures facilitates the trapping of trace elements (PTEs) and radionuclides, providing potential applications for PG as road embankments and fill coatings.

Assessment of radiation dose due to 210Po in water and food samples of Chamarajanagar district, Karnataka, India.

Groundwater is in direct contact with the soil and rocks that dissolve many compounds and minerals including uranium and its daughter products. 210Po is one of the decay products of 238U series that cause internal radiation dose in humans when consumed in the form of water and food, including sea food. Therefore, activities of 210Po have been studied in ground and surface water, and in food samples that are commonly used in Chamarajanagar region of Karnataka, India. The average 210Po concentration in bore well water samples and surface water samples are 3.21 and 1.85 mBq L-1, respectively. In raw rice and wheat, the average values of 210Po are 96 and 41 mBq kg-1, respectively. In millets and pulses, the average activity of 210Po is 157 and 79 mBq kg-1, respectively. Among food items, the highest activity of 1.3kBqkg-1 is observed in marine crabs and the lowest activity of 2.6 mBq kg-1 is found in milk samples. The average ingestion dose due to 210Po in ground and surface water are 2.8 and 1.62μSv y-1, respectively. The ingestion dose due to various food samples to the population is also calculated. Total ingestion dose due to 210Po to pure vegetarian population and general population are 38.09 and 590.80μSv y-1, respectively. The concentration of 210Po in water samples and food samples of this region are in a comparable range with the world and Indian average values and lies well below the recommended guideline level.

Distribution of 210Po activity and soil texture in agricultural soil.

The assessment of 210Po in agricultural soil matrices in different regions of Kerala and Karnataka was studied. The wet ash method was used to find the activity concentration of 210Po. The alpha activity was counted using a silver-activated zinc sulfide counter of 30% efficiency, and the activity was calculated. The average concentration of 210Po activity in soil samples ranged from 0.09 to 20.52Bqkg-1, with an average value of 4.47Bqkg-1. The soil texture was measured using the International Pipette method. Using the IBM Statistical Package of Social Science Software, the frequency distribution curve of 210Po is plotted and found to be lognormal. The data of 210Po are highly skewed, and the Kurtosis has a significant positive value. The 210Po activity concentrations are substantially within the World Health Organization's recommended limits.

A fast method of liquid-liquid extraction for simultaneous 210Pb, 210Bi, 210Po isotopes determination in water samples

Currently, rapid, and efficient methods are pivotal in environmental monitoring within nuclear nations and in the effective management of radiation emergencies. For this reason, a comprehensive comparative analysis was conducted to select a sensitive, rapid, and robust method for determining the natural isotopes of 210Pb, 210Bi, and 210Po in water samples using a single analytical technique. The method is demonstrated using an ultra-low background liquid scintillation spectrometer Wallac 1220 Quantulus. In total, 9 laboratory procedures based on TOPO, TIOA, HDEHP, and scintillation cocktails were compared to determine the optimal method for mutual analysis of three isotopes within the same sequence action. The evaluation was carried out using samples spiked with a prepared SRM 4337 210Pb solution, and it included an assessment of several validation criteria. The recoveries (%) of 210Pb, 210Bi, and 210Po were 57.1%, 99.1% and 78.6% respectively, with the solvent extractor based on 0.20 M TIOA in toluene and using UG AB scintillation cocktail. The minimum detectable activities (MDA) of 210Pb, 210Bi, and 210Po were found to be 17.8, 6.80, and 0.90 [mBq/L] for the measurements using LSC, respectively. However, the least effective was the extraction with HDEHP in toluene/UG XR. The developed procedure is applicable in most laboratory conditions and could be applied to any aqueous samples. This approach gives a new opportunity with fast screening of environmental samples for a radiation risk assessment.

Metals and Natural Radioactivity Investigation of Danube River Water in the Lower Sector

In this paper high-resolution continuum source atomic absorption spectrometry (HRCS AAS) was used for the determination of metal concentrations in Danube water collected in the river lower sector in SE Romania (Braila-Galati-Tulcea). The evaluation of the water natural radioactivity was only performed in Galati sector based on selected radiological parameters: gross alpha/beta activity and radionuclides (210Po, 210Pb, natU, natTh and 226Ra) activity concentrations. The results indicate a temporal and spatial variability of contaminant levels due to anthropogenic inputs and seasonal conditions. For several heavy metals, the registered concentrations exceed the legislated values, imposing a regular monitoring of water quality especially in the case of using the water resource for human consumption, irrigation or aquaculture.

Assessment of cancer risk and radiological effects from 210Po and 210Pb with consumption of wild medicinal herbal plants

BackgroundPlants' raw materials can accumulate chemical elements, including radioisotopes, to some extent and reflect the region they grow in. Due to their high environmental content and toxicity, natural radionuclides – polonium 210Po and lead 210Pb are the most dangerous radioisotopes for human health. Methods70 raw medicinal herbal materials from 54 popular wild-growing medicinal plant species, most of them included in the European Pharmacopoeia, were collected across three regions. In 210 samples, the activity concentrations of 210Po and 210Pb were determined, and their radiotoxicity and cancer risk were calculated. ResultsThe results of 210Po and 210Pb activities measured in herbal raw material were from 0.12 mBq g−1 dry weight in the fruits of the common chestnut (Aesculus hippocastanum) to 19.7 mBq g−1 dw in herb of ground elder (Aegopodium podagraria) for 210Po, while for 210Pb ranged from 0.16 mBq g−1 dw to 34.3 mBq g−1 dw in the same plants. There were statistically significant differences between 210Po and 210Pb content in leaves, herbs, flowers, and fruit. The studies indicated that the estimated annual effective radiation dose from Polish medicinal herbs consumption was low, ranging 0.03–105 µSv from 210Po and 0.02–98.2 µSv from 210Pb, while the risk of cancer morbidity and mortality ranged from 10−5 to 10−9. ConclusionsConsumption of the tested medicinal herbs is safe from the radiological point of view and, based on the predictions related to the calculated risk of cancer, should not increase the probability of its occurrence.

The presence of radiotoxic 210Po and 210Pb in Ukrainian wild medicinal plants and the assessment of related dose and cancer risk.

Herbal plants are considered natural pharmaceuticals but also accumulate chemical elements and compounds at high levels. 210Po and 210Pb are highly radiotoxic and may cause carcinogenesis due to ionizing radiation. Thirteen of the most popular wild-growing herbaceous plant species, mostly included in the European Pharmacopoeia, were collected across Ukraine. 210Po and 210Pb were determined in the medicinal plants, and their radiotoxicity and cancer risk were calculated. The results of 210Po activities measured in herbal raw material ranged from 2.28Bq kg-1 dw (where dw is dry weight) in herb of common horsetail (Equisetum arvense L.) collected near Lviv to 37.7Bq kg-1 dw in leaves of common birch (Betula pendula Roth.) from Rava Ruska. The activity concentrations of 210Pb varied from 0.44Bq kg-1 dw in leaves of common birch from Starokostyantyniv to 28.4Bq kg-1 dw in leaves of common birch from Mizhhirya. There were statistically significant differences between 210Po and 210Pb content in flowers, leaves, and aerial portions. The studies indicated that the estimated annual effective radiation dose from Ukrainian herbs consumption was low, ranging 5.00-82.6 µSv from 210Po and 0.56-35.8 µSv from 210Pb, while the cancer morbidity and mortality risk ranged from 10-4 to 10-6. The presented data indicated no radiological risk related to using herbal plant materials.

РАДИОЭКОЛОГИЧЕСКАЯ ОБСТАНОВКА В РАЙОНЕ ПЛОЩАДКИ УРАНОВОГО НАСЛЕДИЯ – ШАХТА «СТЕПНАЯ» (КАЛМЫКИЯ)

Purpose: To study the radio-ecological situation on the “uranium legacy” site of the former Stepnaya mine in the Republic of Kalmykia. Material and methods: To measure the ambient dose equivalent rate (ADER), the pedestrian gamma survey method was used using a portable spectrometric complex MKC-01A Multirad-M and dosimeter-radiometer MKC-AT6101c. The activity of gamma-emitting radionuclides in soil samples was measured using a stationary gamma spectrometer from CANBERRA. The activities of 210Po and 210Pb were measured using a radiometric installation UMF-2000 following their radiochemical separation from samples. Short-term measurements of activity concentration (AC) and equivalent equilibrium activity concentration (EEAC) of radon were carried out with an aerosol alpha radiometer for radon and thoron RAA-20P2 Poisk. Doses of radiation exposure to biological objects were estimated using dose coefficients provided by ICRP Publication 136 taking into account recommendations R52.18.820-2015. Results: Gamma ADER values at the mine site vary over the range from 0.1 to 0.36 µSv/h, and on 80 % of the area these values do not exceed the background value of 0.14 µSv/h. Along the road from the mine to Narta village the ADER values do not exceed background values with exception of the area around the dam, where in a local part of this area of about 300 m2 these values reach 0.49 µSv/h. The specific activities of natural radionuclides in the soil are below the criteria for classification as solid radioactive waste (SRW). Under the certain weather conditions, radon EEAC inside the buildings on the site reaches 13 kBq/m3, and on the territory 1-1.5 kBq/m3. Ecological risk for the terrestrial biological objects under consideration (grass, soil worm, snake and mouse-like rodents) does not exceed 0.025. Conclusions: The radiation situation at the Stepnaya mine site meets the requirements of SP LKP-91, which were in force until 2020. However, in order to transfer the facility to a local government body, reclamation work should be carried out in accordance with the Federal Law “On the Transfer of Lands or Land Plots from One Category to Another” dated December 21, 2004 No. 172-FZ and GOST R 59057— 2020 «Environmental Protection. Lands. General Requirements for Reclamation of Affected Lands». Doses of exposure to biological objects do not impact significantly on morbidity, reproduction and life expectancy of terrestrial biological objects.

Radiological hazard assessment of 210Po in freshwater mussels (Sinanodonta jourdyi) and golden apple snail (Pomacea canaliculata) in Vietnam.

210Po is a significant source of ionizing radiation that people are exposed to through food globally. This paper presents the wide range of accumulation level of 210Po in the organs of two species of shellfish including freshwater mussel (Sinanodonta jourdyi) and golden apple snail (Pomacea canaliculata), common freshwater species in Vietnam. There was a significant correlation between 210Po activity in muscle to their mass and size of freshwater mussels. In contrast, there was no relation between other organs of both species with their mass and size. The annual effective dose due to consumption of freshwater mussels ranged from 68.7 to 291 μSv year-1 with a mean value of 138 μSv year-1 for muscle and from 321 to 4560 μSv year-1 with a mean value of 1422 μSv year-1 for the hepatopancreas. Meanwhile, the AED for golden apple snail was recorded to be higher with values ranging from 105 to 2189 μSv year-1 with mean value of 673 μSv year-1 for muscle and from 468 to 4155 μSv year-1 with a mean value of 2332 μSv year-1 for hepatopancreas. Thus, the consumption of these two types of shellfish is considered relatively safe, but the hepatopancreas gland must be removed before processing.

Assessment of Be-7, Pb-210 and Po-210 Activities in Airborne Particulate Matter Over Istanbul, Türkiye.

Airborne particulate matter is one of the air pollutants which can have detrimental health effects in the human body. Radionuclides adsorb onto air particles and make their way to humans primarily through inhalation. Naturally-occurring radionuclides, 210Pb and 210Po, are of notable health concern due to their relatively elevated ingestion and inhalation doses. In the current study, activity concentrations of 7Be, 210Pb and 210Po were determined in air particulate matter (PM). PM2.5 was collected on the European side, while PM10 was collected on the Anatolian side of Istanbul. Be-7, 210Pb and 210Po activities were found to be 5.17 ± 2.35, 0.96 ± 0.42; 0.25 ± 0.14 mBq m- 3 in Anatolian side, respectively. Be-7, 210Pb and 210Po activities were found to be 3.81 ± 2.27, 0.62 ± 0.29, 0.29 ± 0.26, mBq m- 3 in European side, respectively. The ratio of 210Po/210Pb was found to be higher (0.47 ± 0.31 for PM2.5 and 0.34 ± 0.27 for PM10) than the global average of 0.1. This result can be explained by the fact that Po is more volatile than Pb and enhanced in the air by the combustion process. Inhalation dose rates of 210Pb and 210Po due to PM10 exposure were calculated to be 7.70 ± 3.30 and 4.05 ± 2.31 µSv year- 1, respectively. Pb-210 bioaccessibility was assessed by the extraction of the particles in simulated lung fluids. Approximately 24.8% of inhaled 210Pb was estimated to be bioaccessible. This study suggests that 210Po and 210Pb activities are partially enhanced in the air particles in Istanbul and should be regularly monitored.

Characterizing 226Ra and its daughters in coastal zone groundwater of a typical human-activity affected bay: occurrence, safety, and source evaluation.

Due to their extremely toxic properties, 226Ra and it daughters (222Rn, 210Pb, and 210Po) in drinking groundwater require monitoring. Recent studies have reported exceptionally high levels of natural 210Po (up to 10,000Bq/m3), 226Ra, and 222Rn isotopes in groundwater. This study aims to provide background data on 226Ra and its daughter radionuclides in the typical agricultural-industrial Dongshan Bay (DSB) before the construction of Zhangzhou Nuclear Power Plant (Zhangzhou NPP). The measurement results indicate that no abnormally high activities of 210Po and 210Pb were detected in the investigated wells. Strong positive correlations between 210Pb and 210Po, as well as between 222Rn and 210Pb activities, suggest that the origins of 210Pb and 210Po in groundwater are strongly influenced by the decay of the parent radionuclides 222Rn and 210Pb, respectively. In the DSB coastal zone groundwater, significant deficiencies of 210Po relative to 210Pb and 210Pb relative to 222Rn were observed, providing further evidence that 210Po and 210Pb are also effectively scavenged due to their geochemical properties (specifically particle affinity) within the groundwater-aquifer system. A systematic comparison among all relevant water bodies in the DSB revealed that the activity concentrations of 210Pb and 210Po in groundwater were the highest, except for rainwater. Based on the evaluation of 210Pb sources, the results imply that submarine groundwater discharge (SGD) is an important pathway for transferring radionuclides (such as 210Pb) from land to the nearshore marine environment, even though the study area has a lower 210Pb background groundwater. By considering all the 210Pb's sources in the DSB, we found low 210Pb background groundwater discharge still needs to be taken into account for small-scale bays. This is because SGD was calculated to be one of the most important 210Pb sources in the bay during observation season. Regardless of whether the system is in a normal state or a nuclear accident emergency state, greater attention should be paid to the groundwater discharge of radionuclides into the ocean.