Radioactivity In Soil Research Articles

Insights into the Genome of a New Strain Serratia rubidaea XU1 Isolated from Radioactive Soil and its Prodigiosin Production and Antimicrobial Properties.

The genus Serratia is a typical red bacterium involved in prodigiosin synthesis. Here, we report the genome sequence of Serratia rubidaea XU1, which was isolated from radiation-contaminated soil in Xinjiang, China. The genome of XU1 is composed of 4,972,898 base pairs with a GC content of 59.25%. The genome sequence contains 4707 genes and encodes 4573 proteins, 79 tRNAs, and 17 rRNAs. The prodigiosin biosynthesis gene cluster was identified and analyzed, showing a sequence similarity of 85.55-96.02% with Serratia rubidaea. After optimizing the biosynthesis process, XU1 was able to achieve a maximum titer of 574 units/cell of prodigiosin at a pH of 7.5 and a temperature of 25°C for 36h. Glycerol at 20g/L and beef extract at 5g/L were used as the carbon and nitrogen sources, respectively. Prodigiosin extracted from XU1 demonstrated inhibition of Escherichia coli, Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa. The availability of the sequenced genome of XU1 will be greatly beneficial and contribute to complementary studies on the biosynthetic mechanisms of prodigiosin.

Natural radioactivity in rocks and soil along Manali-Leh highway: comparative analysis

Natural radioactivity in rocks and soil along Manali-Leh highway: comparative analysis

Assessment of Soil Radioactivity Associated with Risk and Correlation with Soil Properties near Maanshan Nuclear Power Plant, Taiwan

This study analyzes the concentration of radioactive material in the soil near the Maanshan nuclear power plant (NPP). Out of the thirty samples, only one sample was found to have 137Cs radioactivity measuring 2.58 Bq/kg. The activity concentrations were 77.2–517.7 Bq/kg, 3.9–31.6 Bq/Kg, and 5.3–39.1 Bq/kg, respectively, with mean values of 344.4 Bq/kg, 18.6 Bq/kg, and 26.5 Bq/kg for 40K, 226Ra, and 232Th, respectively. These levels are lower than the global average of soil activity concentrations. The activity concentrations varied, with the highest levels being 7–8 times greater than the lowest levels. Clay content had a positive correlation and sand content had a negative correlation with 40K, 226Ra, and 232Th activity concentrations. The activity concentrations followed a normal distribution for 40K, 226Ra, and 232Th. The activity ratios for 232Th/226Ra, 40K/232Th, and 40K/226Ra were 1.43 ± 0.22, 13.1 ± 1.9, and 18.8 ± 4.1, respectively, and ratios show light minerals in the soils. The average values for external hazard indices (Hex) and radium equivalent activity (Raeq) were 0.22 Bq/kg and 83.0 Bq/kg, respectively, both of which are below the recommended limit values of 1.0 Bq/kg and 370 Bq/kg, respectively. The outdoor absorbed dose rate (DRex) and annual effective dose equivalent (AEDex) were 39.0 nGy/h and 47.8 μSv/y, respectively, both of which are lower than the global soil average of 59 nGy/h and 70 μSv/y, respectively. These results indicate that local residents and tourists are not at significant risk of radiological hazards from the soil. The soil activity concentrations can serve as a baseline for continuous monitoring, even after the Maanshan NPP is decommissioned in 2025.

Assessment of Natural Radioactivity and Radiation Hazard in Soil and Rock Samples from Mining Sites within North-Eastern Nigeria

Assessment of Natural Radioactivity and Radiation Hazard in Soil and Rock Samples from Mining Sites within North-Eastern Nigeria

Pioneering study of radioactivity in soil near the Payra 1320 MW Thermal Power Plant, the largest coal-fired thermal power plant in Bangladesh

ABSTRACT Coal combustion increases atmospheric radioactivity, harming those live in the periphery of coal-fired thermal power plants (CFTPPs). A pioneering study has been performed using a high-purity germanium detector by analysing 30 soil samples collected from distances of 50, 600, 1200, and 3000 metres in the periphery of the largest 1320 MW CFTPP, Payra, Bangladesh. The activity concentrations of 226Ra, 232Th and 40K ranged from 19–32, 31–90, and 420–870 Bq/kg, respectively, with most of the samples show 232Th and 40K levels above global averages. Elevated levels of 232Th and 40K in soil around Payra thermal power plant stem from natural minerals, granitic rocks, ash disposal, coal combustion residues, and environmental factors. Radiological hazard indices, including dose rates and cancer risk, exceed global averages, indicating unsafe radiation exposure for coal miners and locals. These findings are crucial for planning coal-fired power plants and stress the need for municipal regulation of fly ash and health monitoring to mitigate risks for workers and residents.

Assessing Radioactivity in Agricultural Soils: Spatial Distribution Patterns, Area-Specific Influences, and Radiological Hazard

Assessing Radioactivity in Agricultural Soils: Spatial Distribution Patterns, Area-Specific Influences, and Radiological Hazard

Assessment of soil moisture on radon levels, radon exhalation, natural radioactivity, and radiological risks in offices and laboratories in GAEC

This study investigates the influence of moisture on soil radon exhalation, natural radioactivity in soil, and indoor radon concentrations in offices and laboratories at the Ghana Atomic Energy Commission (GAEC) and their associated radiological risks to workers. Radon exhalation rates were determined using the Sealed Can method. CR-39 SSNTD detectors were used to measure indoor radon concentrations. Gamma spectroscopy using HpGe detector was used to determine the activity concentrations of U-238, Ra-226, Th-232, and K-40 in the soil samples. The results showed mean concentrations of 14.3 ± 2.0 Bq/kg (CI 95%: 10.0–18.0) for U-238, 145.0 ± 10.0 Bq/kg (CI 95%:123.0–167.0) for K-40, 31.5 ± 6.0 Bq/kg (CI 95%: 24.0–39.0) for Th-232, and 15.6 ± 2.0 Bq/kg (CI 95%:14.0–29.0) for Ra-226. The results showed mean surface and mass exhalation rates of 6.9 ± 2.3 × 10−4 Bq/m2/h1 (CI 95%: 5.7 × 10−4 –12.6 × 10−4) and 2.4 ± 0.4 (CI 95%: 1.9–4.2) nBq/kg1/h1 respectively. The findings revealed mean indoor radon concentrations of 93.0 ± 10.0 Bq/m3 (CI 95%: 88.0–98.0), 111.0 ± 12.0 Bq/m3 (CI 95%: 102.0–119.0) and 145.0 ± 13.0 Bq/m3 (CI 95%: 135.0–155.0) in the offices, laboratories, and basements respectively, with laboratories and basements exceeding the WHO reference level of 100 Bq/m3. A strong inverse relationship between moisture levels and exhalation rates (r = −0.8) was observed, leading to a negative correlation (r = −0.3). Between the moisture levels and indoor radon levels. The research findings indicated a mean annual effective dose of 0.6 mSv/yr. (CI 95%: 0.5–0.6) to the workers, which is well below occupational and public dose limits. The lung cancer cases of workers were computed which ranged from 0.9 × 10−8 to 1.2 × 10−8 cases per million people per year, which is less than the limit range of 170–230 per million people per year recommended by ICRP but remaining with safe radiological limits for workers. This study identified moderate radon exposure risks at the GAEC, exceeding the WHO recommendation. The correlation and trend analysis demonstrate strong relationships between moisture, exhalation rates, radium, and indoor radon.

Radiological hazard assessment of soil from Kasik oil refinery, Nineveh, Iraq

This study explored soil samples in a depth about 10–15 cm, 20 Soil samples were collected systematically from various locations to ensure a comprehensive assessment of the site within Kasik oil refinery, Nineveh Governorate, Iraq, whereby the determination of three natural radionuclides' specific activities was carried out via A p-type coaxial HPGe γ-ray spectrometer, manufactured by CANBERRA, USA. Natural radioactivity in soil is a significant factor for assessing environmental radiation exposure and potential health risks. The 226Ra, 232Th, and 40K radionuclides' mean specific activities in the soil samples were in the 13.10–33.43 Bq/kg, 10.58–22.76 Bq/kg, and 104.90–442.16 Bq/kg ranges, respectively, with overall means of 21.44 Bq/kg, 15.96 Bq/kg, and 255.50 Bq/kg, which are within the worldwide mean levels. The mean radium-equivalent activity (Raeq) was 63.94 Bq/kg, and thus below the 370 Bq/kg international limit. All of the samples' representative level index (Iɣ) and internal and external hazard indices (Hin and Hex) were below the limit of unity, indicating low radiation hazards. The absorbed dose rate resulting from the three primordial radionuclides was in the 19.92–41.46 nGy/h range (mean: 30.20 nGy/h), with an annual effective dose of 0.04 mSv/y. The mean excess lifetime risk of cancer was found to be 0.15 × 10⁻³, and thus under the 0.29 × 10⁻³ world average. The study's results indicate that the natural radionuclides' measured specific activities in the soil samples are below the world recommended values, suggesting that the investigated area is safe in terms of radiological health risks.

An Overview of the Measurements of Primordial Radionuclide Concentrations in Soil and Radon Concentrations in Water Samples

Radiation physics has significantly improved health science, revealing the impact of radioactive materials on humans. These contaminants damage soil and water, leading to health issues like stomach, lung, and leukemia. Radon, a byproduct, poses a significant threat to human health, particularly lung and stomach cancer. Identifying radioactive soil sites is crucial for assessing health concerns among agriculture and construction workers, as natural radionuclides can cause radiological damage. Monitoring these materials can help to assess exposure-related health risks. The goal of this review is to overview and consolidate the works executed between 2007 and 2024 in several countries, including Romania, Turkey, Jamaica, Nigeria, Jordan, Serbia, Spain, Saudi Arabia, Armenia, China, Brazil, Sudan, India, Syria, Iraq, Tunisia, Pakistan, Qatar, and Yemen. Articles commonly employ (HPGe), RAD-7, and CR-39 techniques to measure primordial radionuclides and radon levels. The latest analysis revealed that Nigeria has a significantly higher average radon measurement of 36.1 Bq/L in its drinking water, above the global benchmark threshold of 11.1 Bq/L. The article also, reviews primordial radionuclides in soil research articles in 10 nations. Serbia has the highest 226Ra and 40K soil Bq/kg, which exceeded standards of 32, and 420 Bq/kg of 226Ra and 40K, respectively, while Turkey and Jordan have the lowest values. India has the highest 232Th, and health and safety concerns are addressed. This review work shows that naturally occurring background radiation from radionuclides in soil and radon concentrations in water samples typically has a substantial health impact, posing a major radiation risk to the residents of certain areas. Consequently, our analysis showed that residents should avoid some areas due to radiological hazards. Finally, this review evaluates and elucidates the several factors that influence the elevated and reduced levels of radon in consumption water and the primordial radionuclides activity in soil samples in each country.

Radioactivity of Technosols on thermal power station ash disposal sites: Assessment of potential radiological human‐health risk

AbstractSoil radioactivity is a poorly recognized form of land degradation; however, there are regions all around the world where it can be dangerous to the environment and human health. The aim of the study was to analyze the radioactivity of Technosols developed on thermal power station (TPS) ash disposal sites. Total concentration of uranium (U), thorium (Th), and cesium (Cs), as well as the radioactivity of select radionuclides in Technosols were determined to recognize the level of radioactivity and to assess the potential radiological health risk. Total U, Th and Cs concentrations in Technosols were in ranges 1.5 to 11.3, 4 to 22.9, and 0.2 to 21.3 mg·kg−1, respectively. The radioisotope activities in Technosols (in Bq·kg−1) were in the 1.6–25.5 (137Cs); 29.2–1265 (40K); 26.2–99.9 (228Th); 27.9–100 (228Ra); 20.5–134. (226Ra); 32.8–177 (210Pb); 23.9–144 (238U); 1.2–7.0 (235U) ranges. The activity concentrations were slightly higher than the activities of non‐contaminated soils. Technosols developed from bituminous coal ash had higher 40K, 228Th, and 228Ra activity concentrations than soils developed from lignite ash. Artificial 137Cs occurred in surface horizons of Technosols due to fall of atmospheric dust enriched in 137Cs. Annual effective dose (AED) in Technosols amounted 0.07–0.16 mSv·a−1 and was somewhat higher than the global and Polish average (0.06 and 0.07 mSv·a−1, respectively) for outdoor external terrestrial radiation. The radioactivity of the investigated Technosols is slightly above the average radioactivity of native soils. The radiological human‐health risk related to the analyzed soils is low.

Natural radioactivity in food crops and soil and estimation of the concomitant dose from tin mining areas in Nigeria

Mining of mineral ore is considered one of the anthropogenic sources of elevating the activity concentrations of the natural radionuclides in the environment, which in turn causes an increased risk of human exposure via the food chain. In an attempt to evaluate the radiological burdens resulting from tin mining activities in Nigeria, farm soil and sixty-two samples of different food crops grown around tin mining areas were evaluated for the activity concentrations of 226Ra, 232Th, and 40K using a high-purity germanium detector. The mean activity concentrations of 226Ra, 232Th and 40K in soil were 64.6 ± 29.5, 72.03 ± 28.73 and 680.6 ± 324.3 Bq/kg, respectively. These values were found to be higher than their corresponding world average values. However, the mean activity concentrations of the measured radionuclides in plants were below their respective world average values, as reported by UNSCEAR. The overall average annual ingestion dose due to the consumption of the analysed plants was 151 µSv/y, which is below the reported world average value of 290 µSv/y. The results obtained show that the hazard indices were low enough to cause any immediate radiological health complications due to the ingestion of the crops grown in the studied areas.

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 Natural Radioactivity and Associated Radiological Indicators in Water and Surface Soils Around Beta Glass Plc and Its Environs, Ughelli, Delta State, Nigeria

A radiometric assessment was conducted around Beta Glass plc using sodium iodide detector (3×3-inch NaI (TI)). The study collected 14 soil and 13 water samples from June to July 2022, analyzing radioactivity concentrations of 40K, 238U, and 232Th. The mean specific activity concentrations of 40K, 238U, and 232Th were 184.00±29.73 Bqkg-1, 14.55±2.50 Bqkg-1, and 8.60±1.04 Bqkg-1, respectively, in soil samples, but these elements' concentrations in water were 27.429±5.633 BqL-1, 6.661±1.421 BqL-1, and 2.518±0.361 BqL-1, respectively. The average activity concentrations of 40K, 238U, and 232Th were lower than the safe limit, and the corresponding radiation hazard indices for soil samples were all below the UNSCEAR-recommended acceptable limits. The mean activity concentrations of radionuclides in water samples were higher than the UNSCEAR's recommended international limits for 40K, 238U, and 232Th. Nonetheless, elevated radiological health hazards imply that cumulative dosages may cause cancer, even though these values might not pose an immediate health concern to the local community's people or the workforce.

On the detailed mapping of peat (raised bogs) using airborne radiometric data

This study concerns the applied use of the natural radioactivity in soils. The relevance of airborne radiometric (gamma ray) survey data to peat mapping is now well established and such data have been used in a stand-alone sense and as covariates in machine learning algorithms. Here we present a method to use these data to accurately map the boundaries of peat (raised bogs). This has the potential to assist with the estimation of carbon stocks using a property-based assessment of soil. The significance of such regionally-uniform survey data lies in the subsurface information carried by the measurement which contrasts with the surficial nature of many other covariates. Soils attenuate radiometric flux by virtue of their bulk density (and associated carbon content) and water saturation level. The high attenuation levels in low density, wet peat materials give rise to a distinctive soil response. Here an entirely physics-based assessment of flux attenuation is carried out both theoretically and empirically. Radiometric data from the ongoing Tellus airborne survey of Ireland are used. The study area is characterised by an extensive assemblage of discrete raised peat bogs in a framework of largely mineral soils. Peat is detected by a property contrast with adjacent soils and so we consider all soils within the study area. The relatively low lateral resolution of the airborne data is demonstrated by modelling and we examine the behaviour of a combined spatial derivative of the data. The procedure allows the identification of the edges of the 128 peat polygons considered and indicates other additional potential areas of subsurface peat. The data appear to resolve the differences that exist across three available soil/peat databases that are used for the validation of the results obtained.

Effectiveness of PhosAgro NPK and Gumiton under cultivating potatoes in radioactive soil contamination conditions

Based on the results of three-year production tests, the effectiveness of the use of PhosAgro NPK complex fertilizer and a new organ-mineral complex based on Gumiton peat in potato cultivation technologies on radioactively contaminated sod-podzolic soils in the Novozybkovsky district of the Bryansk region was assessed. Soils differed in the level of fertility and in the density of137Cs pollution. It was shown that leaf treatment of 1 l/ha Gumiton plantings in the potato budding phase without fertilizer contributed to a 19 – 58% increase in tuber yield relative to control, depending on the year. The introduction of PhosAgro NPK fertilizer at a dose of 0.5 t/ha ensured an increase in potato yield by 22 – 42% relative to the control. The joint use of fertilizer and the drug increased the tuber harvest by 12 – 19%, compared to the PhosAgro NPK variant and by 37 – 68% relative to control. The multiplicity of the decrease in137Cs intake into tubers during the treatment of potato plantings with Gumiton was up to 6.4 times in relation to the control, with the combined use of the drug and fertilizer – up to 3.4 times in comparison with the PhosAgro NPK variant. The use of Gumiton and PhosAgro NPK guaranteed the production of potato tubers with137Cs content in accordance with SanPiN 2.3.2 standards. 2650-10. The use of the Gumiton organic-mineral complex and PhosAgro NPK complex fertilizer for production of regulatory clean potato products should be recommended on radioactively contaminated sod-podzolic soils of the Bryansk region.

Evaluation of Radiological Risks Due to Natural Radioactivity in Soils from Swampy Agricultural Farmlands in Kokona, Nigeria

Evaluation of Radiological Risks Due to Natural Radioactivity in Soils from Swampy Agricultural Farmlands in Kokona, Nigeria

Assessment of Radiation Dose Associated with Background Radionuclides in Quarry Soil at Dawakin-Kudu LGA Kano, Nigeria

Naturally occurring radioactive materials (NORMs) are present in different concentrations in the environment as well as quarry depending on the geological formation of the soil. The assessment of any release of radioactivity into the environment is crucial for safeguarding public health, particularly when this radioactivity has the potential to enter the food chain. The quarry located in Dawakin-Kudu Kano has the potential to exhibit elevated levels of natural radioactivity due to intense mining operations. This study presents the assessment of activity concentration in quarry soil at Dawakin-Kudu with a focus on the transfer mechanism from soil to plant. Soil samples were gathered from a quarry site and farmlands situated around the quarry at Dawakin-kudu, plant samples were also collected from the same farmlands and were all analyzed for natural radioactivity, specifically for 226Ra,232Th, and 40K. The gamma-ray spectrometry method, coupled with the Sodium thallium Iodide NaI (Tl) detector was used to measure the activity concentrations of 226Ra,232Th, and 40K. Activity concentrations of natural radioactivity in soil were generally higher than those recorded in plants. The mean activity concentration of the radionuclides in soil ranges from Highest-to-Lowest values as follows 226Ra: 65.24±1.92 Bqkg-1 – 42.41±1.73 Bqkg-1, 232Th: 182.71±1.44 Bqkg-1 – 114.61±1.25 Bqkg-1, 40K: 597.51±3.81 Bqkg-1 – 321.93±3.55 Bqkg-1. The radiological hazard indices were all determined to assess the radiation hazard of the quarry soil. The radionuclides transfer factor showed a higher value for 40K in the order 40K>232Th >226Ra, this implies high bioconcentration of 40K in plants. The findings suggest that consuming plants grown around the quarry location over an extended period could pose substantial health threats to the public. Consequently, the study area may not be safe for residents in the long run, emphasizing the necessity for continuous monitoring of radioactivity concentrations to mitigate the environmental health implications of accumulated...

Utilization of trace elements and radioactivity in fly ash to assess pollution levels around coal-fired power plants

In this study, the results showed that the soil radioactivity concentrations of 232Th and 40K were higher than the reference values given by UNSCEAR, but still within radiologically safe limits. Heavy metal concentrations were within allowable limit according to Vietnamese standards. Radioactivity and metal concentrations in the topsoil did not increase compared with the 30 cm depth after a period of operation. After one year of operation, the gamma dose rates of the area around the plant showed no difference according to the one-way ANOVA test (p = 0.944). The results indicated that after a period of operation, the coal-fired thermal power plant did not shown any significant impact of radioactivity and metals from the fly ash on the surrounding environment.

Natural radioactivity in soil and water of Saudi Arabia: A mixed-studies review

Keeping track of radiation levels within human-inhabited areas is imperative to prevent public exposure. The human body is subjected to out-of-control radiation doses of approximately 82%, resulting from radiation sources such as earthly, cosmic, and internal radiation exposure. One public health issue is the radionuclide contamination in water and soil. In this paper, an overview of radionuclides contamination for some selected radionuclides in waters and soils has been conducted in all Saudi regions to better understand the sources and status of contamination. This review shows certain radioactive elements, such as 238U, 232Th, 226Ra, 40K, and 137Cs, in soil and water, which may have originated from natural or human-made sources. However, the available literature covers radionuclide levels in soil and water across all regions of Saudi Arabia, including the northern, southern, eastern, western, and central parts.

Radioactivity of inert construction and demolition waste from Hong Kong and environmental assessment for marine trial reclamation in Guanghai Bay

Inert construction and demolition waste from Hong Kong (HK public fills) has been used for marine trial reclamation in the Guanghai Bay (GHWT) of the Chinese Mainland. However, an environmental assessment of HK public fills is necessary due to higher radioactivity in HK soils than typical global levels. Here, radiation dose rate, gamma radionuclides and gross beta of HK public fills were analyzed. The origin information was explored using natural primordial radionuclides as fingerprints. Our data show that radiation dose rate of HK public fills before disposal was 0.14–0.54 (0.33 ± 0.03) μSv/h (n = 16,722 data with 2787 ships) in 2014, which is less than the GHWT background. Monthly detection of 238U, 226Ra, 210Pb, 232Th, 228Th, 40K, and gross beta in HK public fills was conducted on three random ships. Their specific activities were <6.27–155.5, 58.7–98.7, <7.83–238.2,97.9–168.6, 87.1–136.0, 463.1–1,018, and 1047–1658 Bq/kgDW, respectively. These results suggest that the radioactivity levels of HK public fills are essentially the same as the GHWT background. The study assessed potential risks using various indices icluding Raeq (Radium equivalent activity), Hex (External radiation hazard index), Hin (Internal radiation hazard index), Iγ (Gamma index), AUI (Activity utilization index), AUI (Activity utilization index), E (Annual effective dose), AGDE (Annual gonadal dose equivalent), RLI (Representative level index), Din (Indoor air absorbed dose rate), Dout (Outdoor air absorbed dose rate), and ELCR (Excess lifetime cancer risk). The study suggests that HK public fills should be used for the trial reclamation rather than building-house materials. This provides valuable insights for the resource utilization and minimizing environmental pollution of HK public fills. The aim is to offer fundamental technical assistance for future waste resource utilization, ecological protection, and restoration in the Guangdong-Hong Kong-Macao Greater Bay Area.