Radium Activity Concentration Research Articles

Radiation protection for Gabes phosphate area residents: Assessing natural radioactivity in soil and potable water samples

Phosphate mining activities are recognized to be one of various industrial processes generating enhanced Naturally Occurring Radioactive Materials (NORM) by introducing natural radionuclides into the surrounding soils and water bodies, posing a risk to human health.This study was carried out to assess the level of natural radionuclides in soils and potable waters collected from the phosphate area of Gabes city, located in southeastern Tunisia, and to evaluate radiation protection measures by estimating radiological health hazard parameters. Gamma spectrometry system employing an HPGe detector was used in this study to assess 40K, 232Th and 226Ra activity concentration in soils. The average values were found to be 163.7, 14.5, and 7.7 Bq kg−1, respectively, which were lower than worldwide average values. The radiological hazard parameters assessed in this study were radium equivalent activity (Ra-eq), external hazard index (Hex), external gamma absorbed rate (GDR), external annual effective dose (Deff) and excess lifetime cancer risk (ELCR). The calculated average values of the above-mentioned parameters were of 41 Bq kg−1, 0.1, 20.2 nGy h−1, 24.8 μSv y−1 and 8.7 × 10−5 all of which were found to be below their permissible standards.For potable water samples, the activity concentrations of radium were analyzed using an HPGe detector and those of uranium were determined by alpha spectrometry. The average activity concentrations of uranium and radium isotopes in underground water samples were found to be higher than those obtained in tap water samples. For both types of water, the average values for all radionuclides were found to be below their respective reference limits.The annual ingestion effective doses were also estimated in this study. The estimated average values for infant and children for underground water samples were higher than the permissible limit of 100 μSv y−1 set by WHO. The 226Ra was the main contributor to the effective doses for different age categories, followed by 228Ra.

Assessment of environmental radiological impact in former metallic mines in Extremadura (Spain): A case study

Metal mining in the Extremadura region was very important in the 19th and 20th centuries. However, due to different reasons the great majority of mines ceased operations, leading to plenty of abandoned mining sites, most of them with on-site waste dumps. Although metal extraction is not radioactive per se, it is considered a NORM activity. In this study, three former mining sites, in which Pb-V-Zn-Ag, Pb-Ag, and Pb-Zn were extracted, were selected to assess the radiological impact on the population and the environment. The external γ exposure was estimated by determining the effective dose and elaborating isodose maps of the sites. The presence of the mining sites increased up to 0.41 mSv/y the effective dose over the surrounding background, which is below the reference value of 1 mSv/y. In only one mining site, the uranium and radium activity concentration of waste dumps were higher than the surrounding soil. The soil to plant (wild grass) transfer factors were similar to other reported values without the influence of NORM activities. So, no enhanced transfer of radionuclides was observed. The radiological impact on the environment was assessed by the risk to non-human biota using the tiered approach developed in ERICA Tool. The sum of the risk quotients of all considered radionuclides in the most conservative Tier 1 was below 1. Total dose rates for several terrestrial Reference Animal and Plants (RAPs) were estimated using Tier 3, obtaining values below 40 µGy/h. Therefore, the impact on non-human biota can be considered as negligible.

Comprehensive Study of Natural Radioactivity in Building Materials: A Case Study in Ica, Peru

This study evaluates radon exhalation rates and assesses the potential radiological risks of external exposure to primordial radionuclides in building materials employed in the Ica region of Peru, particularly those with high uranium content. The radon exhalation rates are currently measured using a combination of a closed chamber and an active monitor. We proposed a novel method that effectively ensured a hermetic seal for the closed chamber and guaranteed that the efficient maintenance of secular equilibrium. The obtained results ranged from below the detection limit (BDL) to a maximum of 52.3 mBq · kg−1h−1. Gamma spectrometry was employed to measure the concentrations of radionuclides by utilizing a 3′ × 3′ NaI detector. The analysis of cement samples revealed a strong positive correlation between the activity concentration of radium and the radon exhalation rate. The activity concentrations for radionuclides varied, with values ranging from BDL to 60.6 mBq · kg−1h−1 for 226Ra, BDL to 22.3 mBq · kg−1h−1 for 232Th, and BDL to 1074 mBq · kg−1h−1 for 40K. These findings contribute valuable insight to decision-making processes in the Peruvian construction industry, particularly regarding material safety and radiological risk management.

Estimation of natural radioactivity in the soil samples around the uranium site, royal village, Khandela, Sikar district, Rajasthan.

The measurements of activity concentration of radium ( 226Ra ), thorium ( 232Th) and potassium ( 40K ) natural radionuclides using high purity germanium ( HPGe ) detector to assess harmful effects on people residing around Royal Uranium Site, Sikar, Rajasthan, India. The activity concentrations range from 29.03±3.72 to 69.95±4.07Bq/kg for 226Ra with a mean value of 47.01Bq/kg, 57.99±6.13 to 113.94±6.54Bq/kg with a mean value of 86.56Bq/kg for 232Th,678.19±76.36 to 1426.55±81.32Bq/kg for 40K with a mean value of 1195Bq/kg. Average Radium Equivalent Activity was measured 261.59±35.48Bq/kg. The total outdoor absorbed gamma dose rate ranged from 78.42 to 157.91 nGy/h with a mean value of 122.12 nGy/h.The average annual effective dose equivalent outdoors and indoors was found 0.75mSv.Mean external (Hex) and internal (Hin) hazard indices are measured 0.70 and 0.82, respectively, for the study area.

Soil and air radon/thoron exhalation rates and radon activity concentrations in the vicinity of Lake Monoun, West region of Cameroon

ABSTRACTOne crucial element to determine the radon amount in the environment is the rate at which radon is exhaled from the subsurface. To assess the radon and thoron potential exhalation in the vicinity of Monoun Lake in the West Region of Cameroon, 28 soil samples were collected around the lake. Radon activity concentration in soil gas and air and the related risk to radon inhalation were evaluated. Radon and thoron exhalation rates, mass exhalation rates, and radon soil gas activity concentrations were derived from a mathematical model as a function of radium content and soil parameters. Radium activity concentrations were estimated using a gamma-ray spectrometry technique with a High Purity Germanium detector (HPGe). The average radon exhalation rate, thoron exhalation rate, radon mass exhalation rate, and thoron mass exhalation rate were found to be 22.7 mBq.m−2.s−1, 5348 mBq.m−2.s−1, 0.018 mBq.kg−1.s−1, and 321 mBq.kg−1.s−1, respectively. The registered radon and thoron exhalation rates were above the world average values of 16 Bq.m−2.s−1 and 1000 Bq.m−2.s−1 published by UNSCEAR, respectively. The calculated thoron exhalation in the study area was about 75.3 times higher than that of radon, which suggests probably more exposure to thoron gas than the radon in the area, despite its shorter half-life. A good positive correlation was found between radon and thoron exhalation rates. The obtained average values of radon activity concentrations in air and annual effective dose were above the world average values of 10 Bq.m−3 and 0.095 mSv published by UNSCEAR, but still below the threshold values of 148 Bq.m−3 and 1.4 mSv set as action levels by USEPA, respectively.

Characterization relationship between multinuclide nonequilibrium gamma radiation dose rate and 226Ra activity concentration in contaminated soil around uranium mines

According to the characteristics of contaminated soil around uranium mines, combined with the pollution path of soil, the response relationship between the gamma radiation dose rate and radium activity concentration in contaminated soil was proposed by using a numerical model and subequilibrium theory. The results showed that the topsoil (depth 20 cm) made the mainly contribution of gamma dose rate (above 88%), and the main nuclide of concern was radium. Additionally, the uranium-radium equilibrium coefficient between 0 and 0.3 had a great influence on the gamma dose rate. The method proposed in this study could quickly identify the radium activity concentration in topsoil by using on-site gamma dose rate monitoring data. Compared with the actual monitoring results within ±10% error control, which had strong operability. This method could quickly identify the location and scope of contaminated soil and guide the on-site monitoring points around uranium mines.

Determination of Activity Levels 226ra, 232th and 40k in some Soil Samples of Federal Polytechnic Kaltungo Main Campus Using Gamma Ray Spectrometry

This paper presents an investigation on radioactivity level of radioactive elements within Federal Polytechnic Kaltungo Main Campus. A total of forty (40) soil samples were analyzed using Gamma-Ray Spectrometry of 76×76mmNaI (TI) detector crystal with radioactivity activity concentration of potassium (40K), Radium (226Ra) and Thorium (232Th) were determined within the study area. Results obtained showed the highest activity concentration of 40K, 226Ra, and 232Th from locations AB3 (898.7365 Bq/kg), AB3 (107.7457 Bq/kg) and AB2 (243.1510 Bq/kg) respectively. The mean activity of 206.7681 Bq/kg obtained for 40K was seen to be lower than the world average of 420 Bq/kg while the mean activity concentrations of 232Th (95.393 Bq/kg) was above the world average of 50 Bq/kg. These upshots could be attributed to the presence of mountains which surround the polytechnic and the quarry activity taking place close to the polytechnic. Equally, Thorium. 226 Ra also had a lowest mean activity concentration of 43.8600 Bq/kg, which is also lower than the world average of 370 Bq/kg. In-situ dose rate measurement of the study area was also carried out using a Radiation Alert Inspector meter and the background radiation reading obtained was seen to fall within a range of 0.11µsv/hr - 0.21µsv/hr, which did not exceed the 1mSv/yr as recommended by National Council on Radiation Protection (NCRP).

Natural radioactivity and radiation risk assessment in fly ash Soil and Water Samples Collected from and around of the AL-Zubaydiyah Thermal Power Plant, wasit, Iraq

In this study, the activity concentrations of radium -226 (236Ra),actinium-228 (238Ac) and potassium -40 (40K) of fly ash , in the Zubaidiyah thermal power station in Wasit province in Iraq were determined using gamma-rays spectroscopy with a hyper -pure germanium (HPGe) and sodium iodide (NaI(TI)) detectors. Reagent system used sodium iodide gamma spectrum and is surrounded by a shield of lead to reduce background radiation and measuring models and calculate the concentrations of natural radioactive isotopes of uranium -238 series, and a series of thorium-232, as well as potassium isotope -40 natural . In general, the results of uranium were higher than the results of thorium with a limit of 3 to 4 times. These are normal results that confirm that there are no previous or old pollutants in the study areas. The risk factors have been calculated in the present study, which include radium equivalent activities ( ), gamma dose rate (D), external hazard index ( ), internal hazard index ( ), annual effective dose which comprise indoor and outdoor effective dose rate (E) It is measured by unit mSv/y and representative level index ( ), respectively.

Time variation of radon in tap water in locations of a Greek area with geological background for elevated radon-in-water concentrations and correlation study between radon, gross alpha, uranium, and radium concentrations

Background: Radon (222Rn), a naturally occurring radioactive gas, dissolves in water, and it can be found in elevated concentrations in public water supplies when water originates from ground sources in areas rich in uranium. An area of great interest for measuring radon-in-water is the Migdonia basin in Northern Greece due to its geological background and because all of its villages are supplied with water from boreholes.
 Objectives: The main aim of this paper was to study the time variation of radon in tap water activity concentration in nine villages of the Migdonia basin supplied with water from boreholes and to determine factors that may affect it. Radon in water correlation between the source (borehole) and the consumption point (tap) was studied for some villages. Also, the correlation among radon, gross alpha, beta, uranium (238U), and radium (226Ra) activity concentration in water was studied.
 Design and methods: Water samples were collected and measured for their radon activity concentration from 66 villages in the Migdonia basin in order to find places with relatively high radon concentrations. The time variation of radon-in-water was studied for villages that showed relatively high radon concentrations for 3–4 years (2018–2022). All samples were measured for their 222Rn activity concentration using gamma-ray spectrometry. Water samples were also analyzed for their gross alpha, beta, and uranium isotopes activity concentration.
 Results and conclusions: Average radon in tap water activity concentrations measured in the area ranged from background concentrations to 185 Bq L-1. The corresponding annual effective doses from waterborne radon inhalation using both UNSCEAR and ICRP dose conversion factors ranged from 0.01 to 0.466 mSv y-1 and from 0.02 to 0.868 mSv y-1, respectively, while radon ingestion annual effective doses varied from 0.007 to 0.324 mSv y-1. Time variation of radon activity concentration in tap water for villages supplied from one borehole or a constant number of boreholes showed relatively low standard deviations (<24%) at a coverage factor of k = 1. Those deviations are probably caused by the time variation of boreholes’ radon concentration and water demand changes. A significant decline in radon concentration from the source (borehole) to the consumption point (tap water) was observed. Therefore, sampling should be performed at the consumption point. However, knowing the supplying borehole concentration is useful as it determines the potential for radon in drinking water. No apparent correlation was found among radon, gross alpha, beta, uranium, and radium concentrations in water. However, in some cases, remedial actions (withdrawal of boreholes) for uranium concentration also decreased radon concentration.

Evaluation of Radionuclide Levels in Drinking Water from Communities near Active and Abandoned Gold Mines and Tailings in the West Rand Region, Gauteng, South Africa

The history of gold mining in the Witwatersrand Basin has led to exponential growth in the economy, residential development, and the abundance of radionuclides in the environment, including the water system. This study aimed to evaluate the radionuclide levels in drinking water (municipal water and groundwater) and the health risks associated with the ingestion of the water in the communities of the West Rand region of Gauteng Province. The activity concentrations of uranium, radium, and thorium radioisotopes were established through alpha spectrometry and the activities were subsequently used to assess the health impacts. The results indicated that the groundwaters contain elevated activities of most radionuclides owing to prolonged periods of water–rock interactions. Similarly, the highest annual effective doses were recorded in groundwaters with a range of 0.0237–0.3106 mSv/yr, with most samples exceeding the WHO- and EU-prescribed limits of 0.1 mSv/yr. Cancer morbidity and mortality risks were higher in females than in males due to the higher life expectancy of females. Nonetheless, all morbidity and mortality risks were well below the USEPA radiological risk limit of 0.001. Based on the findings of this study, continuous monitoring is paramount to ensure that the activities remain below recommended regulatory limits.

MEASUREMENT OF THE CONCENTRATION OF 226RA, 232TH, 40K IN THE SOIL IN SETTLEMENTS ON THE COASTLINE OF LAKE VAN, TURKEY.

In this study, the natural radioactivity level and its effects on the environment of Lake Van, which is the largest lake in Turkey, were investigated extensively. Initially, 254 soil samples have been collected from the districts (Tusba, Edremit, Gevas, Tatvan, Ahlat, Adilcevaz, Ercis) located around the coastline of Lake Van in eastern Turkey. A Na(TI) detector was used to detect activity concentrations of radium (226Ra), thorium (232Th) and potassium (40K) in each collected soil sample. The obtained average results were compared with available data from Turkey and international data base. The average activity in soil samples was measured as 28.0 ± 3.7-43.6 ± 2.2 Bq/kg for 226Ra, 27.3 ± 4.1-55.4 ± 4.8 Bq/kg for 232Th and 377 ± 42- 706 ± 40 Bq/kg for 40K. It was observed that the average concentrations of 226Ra, 232Th, 40K (43.6 ± 2.2, 55.4 ± 4.8, 706 ± 40 Bq/kg, respectively) for Tatvan district and (37.0 ± 3.5, 51.4 ± 4.2, 479 ± 41 Bq/kg, respectively) for Ahlat district were higher than both national and international average value. In addition, radiological effect parameters originating from terrestrial natural radionuclides for the study area; gamma dose rate (Dout), annual effective dose equivalent (AEDE), and lifetime cancer development probability (LCR) were calculated. The Dout, AEDE, LCR (83.0 ± 3.9 nGy/h, 0.102 ± 0.005 mSv/y, 0.36 ± 0.02 x 10-3, respectively) parameters in Tatvan district were found to be above the international allowable value.

Assessment of the Naturally Occurring Radioactive Materials (Norm) In Jos North, Nigeria. A Case Study of the Utan Artisanal Tin Mining Sites

Tin mining and milling can be an avenue for economic and technological development. Mining of this mineral contributes significantly to the distortion of the natural distribution of radioisotopes in the environment. This study assesses the concentration of natural radioactivity due to radioactive elements such as 40K, 238U and 232Th. Soil samples were taken from 20 distinct locations within the Utan mining sites, Jos North, Plateau State, Nigeria. Potassium, radium, and thorium in soil samples from mining sites were determined by measuring their concentration activities using the gamma-ray spectroscopy method. Activity concentrations of potassium, radium and thorium were determined. In soil samples, activity concentrations of 40K, 226Ra and 232Th were established. 40K 196.07±4.91 to 608.07±1.44 with an average of 386.48, 226Ra 0.71±0.02 to 5.11±0.07 with an average of 2.35 and 232Th 14.91±0.74 to 63.71±0.97 with average activity concentrations of 54.78. The average concentration activity of potassium and thorium was slightly above the world recommended average of 370.00 and 40.00 respectively, while radium was below the recommended average. The mines mean absorbed and annual effective dose rates were 14.27-nGy h−1and 18.62 μSvy-1, respectively. This average calculated absorbed dose rate in the air was found to be much less, than the global average of 57-nGy h−1. The absorbed dose is considered low compared to the external natural radiation of about 2000 μSv.y-1, to which no harmful effect is expected directly. However, the mean measured dose rate and calculated dose parameters for the mine were higher than the regulatory limit for public exposure.

222Rn Activity Concentration Measurement and its Radiological Risks in the Environment of Barserin Village, Erbil-Iraq

222Rn Activity Concentration Measurement and its Radiological Risks in the Environment of Barserin Village, Erbil-Iraq

Radiological Risk Assessment for Karstic Springs Used as Drinking Water in Rural Romania

Seasonal variations of the radon and radium activity concentrations in karstic water sources originating in karstic formations were investigated as part of a premiere systematic survey conducted in Romania. A database including a total of 228 drinking water samples collected from 30 distinct water sources adjacent to rural communities was compiled. The radon and radium activity concentrations for all seasons, assessed based on solid scintillation, ranged from 2.1 to 19.7 Bq/L and from 0.6 to 3.0 Bq/L, respectively. Overall, the detected radon and radium contents did not exceed the radioprotection standards recommended by national and European legislation. However, in at least one season, the measured values for 31% of the samples exceeded the 11.1 Bq/L maximum contaminant level for radon in drinking water recommended by the Environmental Protection Agency of the United States. The associated radiological risk, reported in terms of annual effective dose, was calculated to be between 9.8 × 10−6 and 6.0 × 10−5 mSv/y for radon and between 5.9 × 10−5 and 2.7 × 10−4 mSv/y for radium, which are considerably below the WHO (World Health Organization) guidelines at a value of 0.1 mSv/y.

Natural Radioactivity and Radon Exhalation from Building Materials in Underground Parking Lots

The change of natural ionizing radiation and the radon exhalation rates from typical building materials in underground parking lots are presented in the article. The activity concentration of natural radionuclides 232Th, 226Ra, and 40K in six important types of construction materials, which are mostly used in Lithuania, were analyzed using high-resolution gamma spectroscopy. The highest values were found in concrete and ferroconcrete samples: 226Ra 44 and 90 Bq kg−1; 232Th 29 and 34 Bq kg−1; 40K 581 and 603 Bq kg−1. A strong positive correlation (0.88) was observed between radium activity concentration and radon concentration. The activity indexes (Iα and Iγ) and radium equivalent activity (Req) evaluating the suitability of materials for such constructions from the view of radiation safety were determined. The average values of the calculated absorbed dose rate in samples ranged from 18.24 nGy h−1 in the sand to 87.26 nGy h−1 in ferroconcrete. The calculated annual effective dose was below the limit of 1.0 mSv y−1. The values of the external and internal hazards index (Hex and Hin) were all below unity, and the values of Iγ and Iα were below the recommended levels of 0.5 and 1. Dosimetric analysis of underground parking lots was carried out. It was determined that the external equivalent dose rate caused by the 222Rn progeny radiation in the underground car parking lots varies from 17 to 30% of the total equivalent dose rate.

Удельная активность радионуклидов и их взаимосвязь с валовым химическим составом почв

The total heavy metal content and activity concentration of natural radionuclides were obtained in native and anthropogenically transformed soil of the Rostov agglomeration (south of the Russia). The specific activity of natural radionuclides in soils of the has been comparable with indicators typical for chernozems of the Rostov region. Increased activity of 40K, 232Th is observed in the upper horizons, which is due to the origin of the radionuclides themselves and fertilization in the agrogenic period of soils, before the specified areas were included in the urban area. The correlation between activity concentration of radionuclide and total content of heavy metals were derived by Spearman's Rank-Order Correlation. The study was revealed that the activity concentration of thorium and radium doesn’t provide significant correlation with the total content of heavy metals. The group of buried horizons have shown a positive correlation with naturally occurring 40K in contrast with humus horizon (AU). The carbonates-accumulating group of horizons (BCA, [BCA]) have random correlation sign by each of metals. The most significant correlation was observed for the B horizons group.

Natural radium isotopes in waters determined with gamma-ray spectrometry using a HPGe detector

This paper describes a methodology developed to measure the activity concentration of the four natural radium isotopes 226Ra, 228Ra, 224Ra and 223Ra in water samples, using γ-ray analysis performed with a hyperpure germanium detector (HPGe). The detector efficiency was properly determined using a set of thorium standards exhibiting concentrations between 10 and 10,000 μg/g. The developed analytical protocol was applied for evaluating the radium activity concentration in groundwater samples providing from different aquifer systems in three Brazilian states. The results were compared with the guideline reference values for 226Ra and 228Ra as proposed by the Brazilian and WHO legislations.

Natural uranium isotopes and 226Ra in surface and groundwater from a basin of a semiarid region in Brazil

This research aimed to get information about the uranium and radium activity concentrations in surface and ground water in a semiarid region in Brazil. Mean (and range) activity of 0.46 (0.01–1.8), 0.015 (0.0004–0.066) and 0.32 (0.09–1.32) Bq L− 1 were found for 234U, 235U and 238U, respectively. Uranium radioisotopes account for the higher radioactivity in surface and groundwater, 226Ra was found only in few groundwater samples (0.09–0.61 Bq L− 1). 226Ra/238U (0.15–0.43) and 234U/238U (1.18–1.86) activity ratios are indicative of radioactive disequilibrium in groundwater. Expected effective doses from few water sources can be considered significant if untreated water is used for drinking.

Long term behaviour of radium rich deposits in a lake ecosystem

Behaviour of radionuclides released into environment is crucial for further evaluation of any kind of possible effects. Possibility of observation how does a radionuclide behave in natural environment is limited to very few post accidental areas. However, valuable observation can be collected at areas where enhanced concentration of natural radionuclides is presented caused by activity of non-nuclear industry. One example is area affected by release of radium rich brines from coal mines (Upper Silesia, south of Poland) that let one observe radium and its decay product behaviour in freshwater ecosystem from long-term perspective.Selected as long-term observatory site former mine water reservoir allowed identification of processes leading to accumulation of radium in bottom sediments and observation of its further behaviour from 17-years-time perspective. New data were collected during two-years monitoring campaign and compared with archive data on radioactivity in water and sediments collected in 1999. Radium-barium co-precipitation process was identified as main source of sediments heavy contamination, however, radium chemical form resulted from this process is insoluble and not easy migrate to other environmental compartments, what was proved by low 226Ra and 210Pb transfer to water measured under laboratory condition and to biota observed on site. As barium is not always present in mine radium rich brines a discussion is launched what would happen when such waters are released into environment based on simple laboratory experiment.In main conclusion is underlined that the current radium activity concentration in sediments is lower than expected only considering radioactive decay. Distribution of 226Ra, 228Ra and 210Pb in sediment profiles suggest that bio- or mechanical turbation (e.g. local flood) is responsible for significant 226Ra deficiency observed.

Variation of radon-radium gas in geothermal region of Omer-Gecek

In this study, radon gas and radium activity concentrations in the geothermal waters in the Omer-Gecek region of Afyonkarahisar province were measured for a period of 9 months. During this period, the measured radon activity concentration value of Omer region source ranged between 8.997 and 0.076 Bq/L with the average radon activity concentration of 2.714 Bq/L. The radium activity concentration ranged from 0.028 to 0.552 Bq/L with the average radium activity concentration found to be 0.239 Bq/L. The Gecek region radon activity concentration ranged from 0.081 to 3.685 Bq/L with the radium activity concentration of 0.026 to 0.443 Bq/L. The measurement results were compared with the relevant international standards and found that no source exceeds the determined limit values.