Gamma Radiation Dose Rate Research Articles

Comprehensive radiation and ecological study of the city of Tyumen

The article presents the results of comprehensive radiation ecological studies of the territory of Tyumen which consisted of the study of the content of natural (40K, 226Ra, 232Th) and man-made (137Cs, 90Sr) radionuclides in the surface layer of soils, the measurement of radon flux density from the ground and the equivalent dose rate of gamma radiation. The content of natural and man-made radionuclides, radon flux density from the soil surface, equivalent dose rate of gamma-radiation do not exceed the current standards of radiation safety. The data obtained can be used for scientific as well as production purposes in the field of radiation and environmental monitoring of urbanized areas

The seasonal variation of ambient gamma radiation dose rate and health risk assessment in North Coast, Mediterranean Sea

The seasonal variation of ambient gamma radiation dose rate and health risk assessment in North Coast, Mediterranean Sea

Gamma radiation dose rate in high-altitude areas in the Bageshwar, Champawat and Pithoragarh districts of Uttarakhand, India.

Radiation has a deteriorating effect on humans as well as on the environment depending on its level, although we have all been exposed to natural gamma radiation from birth. The presence of radionuclides in rocks, soil, plants, and water is a major factor behind the natural gamma radiation. The present study deals with the study of natural gamma radiation at Bageshwar, Champawat and Pithoragarh districts of Uttarakhand. It also consists of seasonal variations in gamma radiation and its relationship with altitude and geology. The purpose of this study was to investigate the influence of altitude and geology on natural gamma radiation dose rate data in high-altitude areas of India. The highest gamma radiation value was 444nSv/h in the summer and 342nSv/h in the winter. The investigation recorded the gamma radiation up to 2542.20maltitude, indicating that the geology of the areas is more relevant than the altitude. Few sites in such a high-altitude zone were found to exceed the value of 200nSv/h, as reported by UNSCEAR. This research is necessary in order to consider the human health and climate changes, both of which are part of the action plan for the United Nation's Sustainable Development Goals (SDG 3, SDG 13).

The role of pharmaceutical analysis in ensuring the safety of drug radiation sterilization

Radiation sterilization is a widely used method for ensuring the sterility of medical and pharmaceutical products. The process involves exposing the products to ionizing radiation, which destroys microorganisms such as bacteria, viruses, and fungi, rendering the products sterile. The most commonly used ionizing radiation sterilization methods are highly penetrating with low dose rate gamma-irradiation from isotopic sources and less penetrating but with high dose rate e-beam from accelerators. This review provides an overview of the principles and applications of radiation sterilization, including the types of radiation sources used, the differences between them that may affect the efficacy of the process, and the regulatory requirements for radiation sterilization of active pharmaceutical ingredients and drug dosage forms. This review focuses on the analytical methods used to evaluate the effect of irradiation on drug substances. Finally, it discusses studies on radiation sterilization of various groups of drugs, including anthracyclines, β-lactam antibiotics, chloramphenicol and its derivatives, sulphonamides, antifungal drugs, β-blockers, nonsteroidal anti-inflammatory drugs, steroids, and others, and drug dosage forms.

Uranium tailings in the Istiqlol city: history, problems, solutions

The article provides an overview of the problems associated with the uranium tailings in Istiqlol city. Many uranium heritage sites in Central Asia, including the uranium tailings in Istiqlol, hadn’t been mothballed before the collapse of the USSR. The burial complex consists of a quarry, dumps of the “Poor Ores Factory”, an unpreserved open mine, destroyed industrial buildings and four tailings which contain 12 million tons of the uranium production waste. In the area of the tailings, the ambient dose rate of gamma radiation is 0.5–0.6 μSv/h, and at some points it reaches 3.0–4.0 μSv/h. The average annual radon emission from the surface is estimated at 3.9×1011 Bq/year. The contaminated areas also include the Sarym-Sakhly Sai stream, mine, industrial and quarry waters, which are characterized by an increased content of 234U, 238U and 226Ra. The facilities aren’t physically fenced, allowing free access for the public and livestock. Natural disasters such as mudflows, landslides, and earthquakes can lead to an ecological disaster. Attention is paid to the ways of solving problems such as monitoring radionuclides in water, soil, and air; working with the local population to inform and involve them in rehabilitation work; donors search. The Program for the Implementation of the National Concept for the Rehabilitation of Tailings of Uranium Ore Processing Wastes for 2016–2024 was developed and approved by the Government of the Republic of Tajikistan to minimize the radiation impact on the population and the environment. Implementation of the Program requires significant financial investments and trained personals in the field of radiation safety. Only through the joint efforts of the state, population and international organizations is it possible to fully carry out rehabilitation works. Only by joint the state, public, and international organizations efforts, it is possible to solve these problems. Also, one of the main reasons why the population had received unnecessary overexposure was its ignorance of the danger of using water, soil and building materials contaminated with radionuclides. Therefore, the culture of radiation safety should be studied starting from middle school, where students will be taught about ionizing radiation and possible ways of exposure. Then, both cases of intake of radionuclides into the body, which could have been avoided, and radiophobia among the population living near the extraction and processing of uranium ore, will be much lower. Some social and economic aspects are also touched upon.

Assessment of secondary radioactive contamination of a decontaminated land plot located on the territory of a recreation base in a wooded area

The article presents results of a long-term (1998–2021) radiological monitoring survey of a recreation base located in a wooded area in the zone of radioactive contamination after the accident at the Chernobyl nuclear power plant. Local mechanical decontamination of the soil had been made on the territory of the base in 1997. The evaluation of the secondary radioactive contamination of the decontaminated territory was performed by comparing dynamics of the radiological situation at the treated plot and the control, nondecontaminated, part of the base according to four main criteria: 1) dose rate of gamma radiation in the air from cesium radionuclides; 2) inventory of 137Cs in soil; 3) vertical distribution of 137Cs in soil; 4) activity concentration of 137Cs in plants and fungi. In 1998, the value of the 137Cs inventory in the upper 20 cm of soil in the control part of the territory of the base and in the decontaminated plot was 930 kBq/m2 and 143 kBq/ m2, respectively. By 2015, the value of the 137Cs inventory in the control area and the decontaminated plot had significantly decreased: by 35% and 36%, respectively. A decrease in the dose rate of gamma radiation in the air at the decontaminated plot and control area proceeded at the same rate, which is currently mainly determined by the decay of 137Cs. There was a gradual self-restoration of the forest ecosystem at the plot subjected to decontamination. Activity concentration of 137Cs in biota (pine, edible mushrooms) in the treated plot was many times lower than that in the control part of the recreation base. In general, there was no significant secondary radioactive contamination of the decontaminated plot in the 24 years after the intervention.

Chornobyl radiation spikes are not due to military vehicles disturbing soil

On 25th February 2022, increased gamma radiation dose rates were reported within the Chornobyl Exclusion Zone (CEZ). This coincided with Russian military vehicles entering the Ukrainian part of the CEZ from neighbouring Belarus. It was speculated that contaminated soil resuspension by vehicle movements or a leak from the Chornobyl Nuclear Power Plant complex may explain these spikes in radiation dose rates. The gamma dose rate monitoring network in the CEZ provides a crucial early warning system for releases of radioactivity to the environment and is part of the international safeguards for nuclear facilities. With the potential for further military action in the CEZ and concerns over nuclear safety, it is essential that such anomalous readings are investigated. We evaluate the hypotheses suggested to explain the apparent gamma dose rate increases, demonstrating that neither military vehicle-induced soil resuspension nor a leak from the Chornobyl Nuclear Power Plant are plausible. However, disruption of the Chornobyl base-station's reception of wireless signals from the gamma dose rate monitoring network in the CEZ may potentially explain the dose rate increases recorded.

Assessment of Outdoor Terrestrial Gamma Radiation Dose Rates of Serule Village, Botswana

Assessment of Outdoor Terrestrial Gamma Radiation Dose Rates of Serule Village, Botswana

Ionizing Radiation in PET Center and Level of Their Exposure on Personnel and Patients

CONTENTS
 Introduction
 1. Dose rate of gamma and neutron radiation in the cyclotron facility
 2. Ionizing radiation in radiochemical laboratory and personnel doses
 3. Radiation sources in PET department and their contribution in personnel radiation exposure
 4. Doses of patients under performance of PET/CT study
 Summary

Dose rate dependent reduction in chromatin accessibility at transcriptional start sites long time after exposure to gamma radiation

ABSTRACT Ionizing radiation (IR) impact cellular and molecular processes that require chromatin remodelling relevant for cellular integrity. However, the cellular implications of ionizing radiation (IR) delivered per time unit (dose rate) are still debated. This study investigates whether the dose rate is relevant for inflicting changes to the epigenome, represented by chromatin accessibility, or whether it is the total dose that is decisive. CBA/CaOlaHsd mice were whole-body exposed to either chronic low dose rate (2.5 mGy/h for 54 d) or the higher dose rates (10 mGy/h for 14 d and 100 mGy/h for 30 h) of gamma radiation (60Co, total dose: 3 Gy). Chromatin accessibility was analysed in liver tissue samples using Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-Seq), both one day after and over three months post-radiation (>100 d). The results show that the dose rate contributes to radiation-induced epigenomic changes in the liver at both sampling timepoints. Interestingly, chronic low dose rate exposure to a high total dose (3 Gy) did not inflict long-term changes to the epigenome. In contrast to the acute high dose rate given to the same total dose, reduced accessibility at transcriptional start sites (TSS) was identified in genes relevant for the DNA damage response and transcriptional activity. Our findings link dose rate to essential biological mechanisms that could be relevant for understanding long-term changes after ionizing radiation exposure. However, future studies are needed to comprehend the biological consequence of these findings.

Terrestrial gamma radiation dose (TGRD) levels in northern zone of Bauchi, Nigeria: mapping and statistical relationship between gamma dose rates and geological formations

This present study aims to obtain baseline data of environmental terrestrial radiation and to assess the corresponding health risk in the ambient environment in Bauchi north. The Terrestrial gamma radiation dose rates (TGRD) of study area were measured on-site using a portable Radiation alert milli roentgen (mR) survey meter, with a total of 280 measured points which covered all geological formations of the study area. The TGRD ranged from 60.90 nGyh-1 to 313.20 nGyh-1 with a mean value of 165.48 nGyh-1, which is about two times higher than the world average value of 59 nGyh-1 . Geological formation (Granites) was found to have the highest mean TGRD value of 194.88 nGyh-1. Likewise, Geological formation (Quartenary sedimentary) appeared to have the lowest mean TGRD value of 151.82 nGyh-1. The map for the distribution and exposure rate due to TGRD for the study area was also plotted using Golden surfer 12 software. One-way ANOVA was used to investigate the variation of the significant difference between the geological formations with TGRD, which shows the influence of geological formation on the measured TGRD values of the study area. Measured data could further be used to evaluate the public radiation exposure and in formulating safety standards and radiological guidelines.

Micro-mapping of terrestrial gamma radiation dose rate in typical urban homes in Miri City (Sarawak, Malaysia)

Micro-mapping of terrestrial gamma radiation dose (TGRD) at meter grid spacing in and around four urban homes in Miri City shows rates ranging from 70 to 150 nGy/h. Tiled surfaces (floors and walls) vary between properties and have a clear and significant influence on TGRD which is highest in kitchens, washrooms and toilets. Application of a single indoor value for annual effective dose (AED) may lead to underestimations of up to 30%. The AED is unlikely to exceed 0.8 mSv in homes of this type in Miri, which is within recommended guidelines.

A Monte Carlo simulation study of L-band emission upon gamma radiolysis of water

Several studies have confirmed visible light and ultraviolet emission during water molecule radiolysis; however, radiofrequency emission has been scarcely investigated. This simulation study has revealed that the gamma radiolysis of water creates excited hydrogen atoms which emit radio recombination L-band (1 GHz–2 GHz) radio waves of sufficient strength that a radio-imaging device can detect. The physical and physicochemical stages of radiolysis of water have been modeled via application of Monte Carlo simulation techniques (utilizing Geant4) up to 1 ps from the onset of gamma photon interaction with water molecules. Subsequently an L-band emission analysis up to a few ms duration was accomplished to obtain and understand RF power emission characteristics as a function of gamma radiation dose rate. The generated L-band 1.4 GHz RF power is 19 dBm per one Gy/h of absorbed dose rate. The generated RF power varies linearly with absorbed dose rate up to 3.38 Gy/h, beyond which non-linearity manifests due to line broadening. Unlike conventional gamma radiation detectors, the proposed RF-based gamma radiation detection model indicates that the detection sensitivity of the RF detector does not deteriorate rapidly with an increase in altitude above radiation source at ground. Consequently, source-detector standoff distances are increased significantly at least up to two orders of magnitude higher than the current gamma radiation detection scenario. Preliminary experiments were conducted using an experimentally simulated signal, an RF transmitter and an RF receiver along with suitable data acquisition unit. This was performed to determine the sensitivity of the RF receiver, which would enable laboratory scale testing with safe gamma sources of dose rate less than 0.1 mGy/h.

Gamma radiation dose rate distribution in the Anand, Bharuch, Vadodara, and Narmada districts of Gujarat, India.

Radiation is present everywhere in the earth, and human beings are continuously exposed to gamma radiation. The health consequences of environmental radiation exposure are a serious societal issue. The purpose of this study was to analyse outdoor radiation in four districts of Gujarat, India: Anand, Bharuch, Narmada, and Vadodara duringsummer and winter seasons. This study illustrated the influence of lithology of areas on gamma radiation dose values. Summer and winter seasons are the primary factors that alter the causes directly or indirectly; therefore, the influence of season fluctuation on radiation dose rate was investigated. The annual dose rate and mean gamma radiation dose rate values from four districts were found to be greater than the global population weight average value. The mean value of gamma radiation dose rate from 439 locations in thesummer and winterseasons was 136.23 nSv/h and 141.58 nSv/h, respectively. According to a paired differences sample study, the significance value between outdoor gamma dose rate insummer and winterseasons was 0.05 indicating that seasons have a significant impact on gamma radiation dose rate. The impact of various types of lithology on gamma radiation dose was studied in all 439 places, and the statistical analysis revealed that there was no significant association between lithology and gamma radiation dose rate in the summer season, but a relationship between lithology and gamma dose rate was observed in the winter season.

Estimation of indoor gamma radiation dose rate from concrete blocks constructed from tin mine tailings

The use of building materials made from geological sources contributes greatly to the indoor radiation exposure of human. As a result, it is critical for public health that building materials be screened for elevated radionuclide concentrations. This research measures the primordial radionuclide content of concrete blocks derived from mine tailings and also estimates the indoor annual effective dose rate (AEDR) and associated parameters. Furthermore, it presents a simple empirical relationship for evaluating dose rate per unit specific activity due to radionuclides from a wall of arbitrary dimensions. Twelve concrete blocks constructed using tin mine tailings as fine aggregates were collected locally and analyzed for 235U, 232Th and 40K content using gamma spectrometry analysis. The concentration of 238U ranged from 86.29 to 197.73 Bq/kg with a mean of 120.93 Bq/kg. Also, the specific activity of 232Th and 40K is within the limits: 99.01–353.67 Bq/kg and 500.71–1021.77 Bq/kg with mean values of 248.31 Bq/kg and 635.10 Bq/kg, respectively. Obtained dose rate per unit specific activity agreed well with data from literature. Using the derived values of dose rate per unit specific activity, the annual effective dose rate (AEDR) obtained from a typical Nigerian room varies significantly from that obtained from equations in referenced documents where a different room configuration was used. The mean AEDR from the realistic Nigerian room (3.6 × 3.6 × 3 m3) was higher than the world average value but less than the recommended safety limit of 1 mSvy−1. Some of the blocks with AEDR more than the safety limits were recommended for use in superficial quantities for building construction. The model derived in this study can be applied to calculate dose rates within any room configuration.

The concentrations of artificial and natural radionuclides in the bottom sediments of south-west Altai territory water bodies

The purpose of the research is to study and analyze the environmental condition of small streams and reservoirs in the southwestern part of the Altai Territory (Russia), which were previously exposed to radiation as a result of nuclear tests at the Semipalatinsk test site. Conducting the research, the authors obtained the results of studying the content of artificial and natural radionuclides in the bottom sediments of the water bodies under investigation. Sampling of bottom sediments and their analytical studies were carried out in 2020–2022. The sampling involved measurements of the dose rate of bottom sediment gamma radiation. Having dried and ground the samples, the authors measured the flux density of alpha and beta particles from the surface. Laboratory studies of the samples were carried out using highly sensitive analytical equipment including an ORTEC GEM25P4-70 gamma spectrometer, an Alpha Analyst A1200-32AM CANBERRA alpha spectrometer, and a TRI-CARB 3110TR PerkinElmer beta spectrometer. The activities of natural radionuclides (potassium-40, thorium-232, radium-226) and artificial radionuclides (americium-241, plutonium-239+240, cesium-137 and strontium-90) were identified in the bottom sediments. It was determined that the radiation parameters of bottom sediments of water bodies in the southwestern part of the Altai Territory do not exceed the standard level, and the remains of traces of nuclear tests that took place at the test site are not found in the studied water bodies today.

In situ assessment of terrestrial gamma radiation dose and associated radiological hazards in Katsina State, Nigeria

ABSTRACT Terrestrial gamma radiation dose (TGRD) rates were measured in situ from different locations in Katsina State, Nigeria, using a portable radiation survey metre based on geological formations and soil types. The measured TGRD rates ranged from 45 to 271 nGyh–1 with an average value of 116 ± 1 nGyh–1. Geological formation (silicified sheared rock) and soil type (lithosols and ferruginous crusts and ferruginous tropical soils) appeared to have the highest mean TGRD values of 163 and 134 nGyh–1 with sandstone geological formation and alluvial and hydromorphic soils having the lowest TGRD with values of 80 and 61 nGyh–1, respectively. One way ANOVA results shows that the tested null hypothesis was rejected. Thus, indicating that there exists a strong relationship between the various geological formations, soil types with the measured TGRD values based on the alternate hypothesis. Human health hazard indices like annual effective dose equivalent (AEDE), lifetime outdoor annual equivalent dose, and relative excess lifetime outdoor cancer risk associated with the mean TGRD of the study area were also calculated and found to be 0.711, 9.955 mSv, and 5.79 × 10–4, respectively. These values were higher than the world average values but favourable compared with the safety limits recommended by ICRP.

ACTIVITY CONCENTRATION OF RADIONUCLIDE AND EXTERNAL DOSE RATE IN BOTTOM DEPOSITS OF BRIT LAKE IN THE CHОRNOBYL EXCLUSION ZONE

The profiles of the vertical distribution of the gamma dose rate and activity concentrations of 90Sr, 137Cs, 154Eu, and 241Am in the bottom sediments of Brit Lake were obtained. The lake is located within the dammed section of the Krasnenska floodplain of the Pripyat River in the Chоrnobyl Exclusion Zone (51.44844°; 30.06020°). The values of the dose rate and activity concentration of 137Cs in the sediments reached 23 μGy h−1 and 43 Bq∙cm−3. In the lake Brit radioactive contamination of bottom sediments did not depend on the depth of the lake due to the washing of radionuclides from the water intake. A weak correlation was observed between values of in-situ measured and calculated gamma dose rates in bottom sediments. The average calculated and measured dose rates of gamma radiation in bottom sediments of the lake varied within the range of 1.3-19 μGy h−1 and was compatible with the internal radiation dose to fish (5-15 μGy h−1). Contribution of radionuclide content in water to the gamma dose rate does not exceed 2 nGy h−1. In October 2021, appropriate equipment for acoustic 3-D telemetry and individual dosimetry of various fish species was installed in the lake to reduce uncertainty in estimates of doses of external exposure to aboriginal fish in the lakes

Верификация двухмерной модели эксперимента ослабления нейтронного и фотонного излучения ядерного реактора радиационно-защитным металлогидридным композитом

The paper presents experimental studies of the attenuation of neutron and photon radiation of a nuclear reactor by a radiation-protective metal hydride composite, as well as the distribution of dose and spatial-energy characteristics of primary and secondary gamma radiation in the material. It is shown that the formation of the gamma radiation dose rate behind the protection is due to the capture gamma quanta formed in the initial layer of the material. Based on the results of the reactor protective properties of the material, the verification of the computational model of the experiment in two-dimensional geometry by the method of discrete ordinates according to the DORT program was carried out. The deviations between the calculated and experimental values of the relaxation lengths for fast neutrons were no more than 5 %, for gamma radiation no more than 7 %, which confirms the validity of the calculation methods used and the possibility of using the data obtained with a high degree of reliability when designing the geometry of the radiation protection of a reactor made of metal hydride composite

Оценка мощности дозы гамма-излучения от контейнера с РАО

Assessment of personnel exposure from various operations performed inside radioactive waste (RW) storage facilities is seen as an essential task under the safety assessment of such storage facilities. However, radiation scattered from the structures inside the premises of RW storage facilities is often not taken into account in the assessment of personnel exposure doses. Characteristics of the radiation field from RW containers have been calculated under a few studies. For example, the radiation fields were calculated based on some engineering approaches and the Monte Carlo method using specialized software. This paper focuses on the Monte Carlo calculations of the gamma radiation dose rate from a volumetric cylindrical source located in a RW storage facility. The study evaluates the contributions of scattered radiation from the walls, floor and ceiling of a storage premise to the absorbed dose also considering the case of a flooded floor. The paper compares the calculated radiation dose rates with those evaluated by integrating the source volume for axisymmetric geometries with no account taken of scattered radiation. The calculations show that depending on the distance from the source if no scattered radiation from all the wall, floor and ceiling structures of a storage facility is accounted for, the dose rate may be underestimated by up to two times.