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Each nuclear weapon test contributes to a global burden of released radioactivity. Between 1945 and 1996, more than 2,000 nuclear tests were conducted, three-quarters of which were underground. Underground nuclear tests involved placing the nuclear device in a cavity drilled or excavated beneath the surface. The goal was to contain the explosion and its effects to the immediate vicinity of the detonation point, ultimately minimizing the release of radioactive materials into the atmosphere. While these tests successfully curtailed the atmospheric release and radioactive fallout, they created dynamic responses within crustal formations caused by local shock waves from the explosion. This paper discusses the legacy of underground nuclear testing, addressing issues from containment failure to the phenomenological effects after underground detonations and the pathways of subsequent dispersal of radionuclides to the environment. [ABSTRACT FROM AUTHOR]

This study investigates the levels of natural and artificial radioactivity in rice samples collected from various local markets in Islamabad, Pakistan. The 226Ra, 232Th, and 40K activity concentrations were measured through gamma-ray spectrometry with a NaI(Tl) detector. The average activity concentrations were 1.67 ± 1.19 Bq kg−1 for 226Ra, 3.31 ± 1.83 Bq kg−1 for 232Th, and 88.51 ± 11.65 Bq kg−1 for 40K. Calculated radium equivalent (Raeq) values ranged from 7.35 to 18.08 Bq kg−1, with a mean value of 11.11 Bq kg−1, all below the permissible maximum of 370 Bq kg−1. The absorbed dose rates ranged from 6.85 to 16.39 nGy h−1, with an average of 10.64 nGy h−1, falling below the acceptable limit of 51 nGy h−1. The outdoor and indoor radiation hazard indices (Hex and Hin) had mean values of 0.03, both below the threshold value of one. The external and internal hazard indices (Iγ and Iα) were both 0.088, also below the critical value of one. The excess lifetime cancer risk (ELCR) ranged from 0.28 to 0.11, with a mean value of 0.18, which is less than the critical value of one. Overall, the radioactivity levels in the analyzed rice samples are within the acceptable limits set by the International Commission on Radiological Protection and are below global averages. These results offer important insights into the radiological safety of rice consumption in the study area. [ABSTRACT FROM AUTHOR]

Abstract The metabolism and disposition of zamicastat, a reversible dopamine β-hydroxylase (DβH) inhibitor, developed for treatment of Pulmonary Arterial Hypertension (PAH), were investigated in rats after oral and intravenous administration of [14C]-zamicastat.Zamicastat was rapidly absorbed and widely distributed to peripheral tissues, with total radioactivity almost completely recovered 168 h post-dose. Its main route of excretion was via faeces, whilst urine and expired air had minor roles.Maximum plasma concentration of zamicastat-related radioactivity occurred in the first hours, remaining quantifiable up to 144 h. The unchanged zamicastat plasma peak was 2 h post-dose and declined to low levels over 24 h.Zamicastat metabolism occurs largely during the first 8 h with only one metabolite identified in the latest time-point (96 h), the isothiocyanic acid/thiocyanic acid (tautomeric forms). Zamicastat metabolic pathway involved multiple reactions comprising desulphurisation, oxidative desulphurisation, N-debenzylation followed by further oxidation or N-acetylation, and the unexpected multistep metabolic pathway leading to isothiocyanic acid/thiocyanic acid.The metabolism and disposition of zamicastat, a reversible dopamine β-hydroxylase (DβH) inhibitor, developed for treatment of Pulmonary Arterial Hypertension (PAH), were investigated in rats after oral and intravenous administration of [14C]-zamicastat.Zamicastat was rapidly absorbed and widely distributed to peripheral tissues, with total radioactivity almost completely recovered 168 h post-dose. Its main route of excretion was via faeces, whilst urine and expired air had minor roles.Maximum plasma concentration of zamicastat-related radioactivity occurred in the first hours, remaining quantifiable up to 144 h. The unchanged zamicastat plasma peak was 2 h post-dose and declined to low levels over 24 h.Zamicastat metabolism occurs largely during the first 8 h with only one metabolite identified in the latest time-point (96 h), the isothiocyanic acid/thiocyanic acid (tautomeric forms). Zamicastat metabolic pathway involved multiple reactions comprising desulphurisation, oxidative desulphurisation, N-debenzylation followed by further oxidation or N-acetylation, and the unexpected multistep metabolic pathway leading to isothiocyanic acid/thiocyanic acid. [ABSTRACT FROM AUTHOR]

The pharmacokinetics, metabolism, excretion, mass balance, and tissue distribution of [14C]aficamten were evaluated following oral administration of an 8 mg/kg dose in Sprague Dawley rats and in a quantitative whole-body autoradiography study in Long Evans rats. [14C]Aficamten accounted for ∼80% and a hydroxylated metabolite (M1) accounted for ∼12% of total radioactivity in plasma over 48-h (AUC0–48). Plasma tmax was 4-h and the t1/2 of total plasma radioactivity was 5.8-h. Tissues showing highest Cmax exposures were myocardium and semitendinosus muscle. Most [14C]aficamten-derived radioactivity was excreted within 48-h post-administration. Mean cumulative recovery in urine and faeces over 168-h was 8.3% and 90.7%, respectively. In urine and bile, unchanged aficamten was detected at <0.1 and <0.2% of dose, respectively; however, based on total radioactivity excreted in urine (8.0%) and bile (51.7%), approximately 60% of dose was absorbed. [14C]Aficamten was metabolised by hydroxylation with subsequent glucuronidation where the most abundant metabolite recovered in bile was M5 (35.2%), the oxygen-linked glucuronide of hydroxylated aficamten (M1a). The major metabolite detected in faeces was a 1,2,4-oxadiazole moiety ring-cleaved metabolite (M18, 35.3%), shown to be formed from the metabolism of M5 in incubations with rat intestinal contents solution. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Microplastics have become a ubiquitous contaminant, but their fate in food animals is largely unknown. In this study, [14C]-polystyrene microplastic (PS-MP) particles were orally dosed to lactating sheep to evaluate their absorption and disposition. Elimination of the [14C]-PS-MP was predominately through faeces with faecal radioactivity peaking at 24 h post-dosing but continuing to be present throughout the entire 72 h study period. Only a small fraction (≤ 1%) of the dosed [14C]-PS-MP was present in blood, milk, and urine. Pharmacokinetic analysis of blood plasma radioactivity, using non-compartment modeling, indicated rapid absorption (T1/2 0.4 to 3 h) with slow elimination (T1/2 37 to 48 h). Radioactivity in milk and urine had similar elimination patterns with radiocarbon activities peaking 24 h post-dosing with detectable elimination throughout the 72 h study period. No radioactivity was quantifiable in tissues at the 72 h withdrawal period. [ABSTRACT FROM AUTHOR]

As a result of firing pulverized coal in thermal power plants, enormous amounts of fly ash (FA) are produced as industrial waste. The release into the atmosphere and storage of this industrial waste remains one of the major environmental problems that threaten human health by contributing to air, water, and soil pollution. The recovery and reuse of FA in the construction industry is the only economic solution to the existing problem. In this study, the potential radiological risk caused by the usage of FA in concrete and cement production as a main component and its storage in landfill sites was evaluated for people and works by estimating radiological parameters (activity concentration and alpha index, annual effective doses, and the corresponding excess lifetime cancer risks) based on activity concentrations of terrestrial radionuclides in FA. Also, the radiological risk to the workers working in the FA landfill site was evaluated using the Residual Radioactivity Onsite 7.2 code. The average activity concentrations of terrestrial radionuclides in FA samples from the Tunçbilek lignite coal-fired thermal power plant at Kütahya province of Turkey were measured as 417, 156 and 454 Bq kg−1 for 226Ra, 232Th and 40K, respectively. When using up to 35% by mass of FA in cement and concrete, the average values of the radiological parameters revealed that they were within the recommended safety limits. However, code estimations showed that a regular worker in FA storage would be exposed to a total effective dose rate greater than 3 mSv y−1. [ABSTRACT FROM AUTHOR]

Purpose: It has been known for many decades that radiation exposure of the developing embryo or fetus may cause two fundamentally different types of severe health effects: on the one hand, radiation may interfere with the normal intrauterine development, on the other hand, radiation may induce leukemia and cancer which become manifest in childhood. A large amount of epidemiological and experimental data has recently been presented which might be used to improve our understanding of underlying mechanisms and setting radiation protection standards. Yet, ecological studies in the populations exposed to increased levels of radiation in regions contaminated by radioactivity released from reactor accidents (Chernobyl, Fukushima) do not provide solid evidence which would contribute to this aim. On the other hand, well designed experimental studies demonstrated the multifactorial mechanisms which lead to different health effects after radiation exposure in utero. Conclusion: There is no convincing evidence, neither from epidemiological nor experimental data of the existence of a dose threshold for developmental defects after radiation exposure in utero. This must be taken into account in the revision of rules and regulations of radiation protection in medicine. [ABSTRACT FROM AUTHOR]

The present work deals with identifying and determining the activity levels of naturally occurring radionuclides 226Ra and 232Th series, their decay products and 40K in chemical and organic fertilisers used in the Chattogram area, Bangladesh. A total of 39 samples collected from retail markets were investigated, out of which 28 are chemical fertilisers and the others are organic fertilisers. The average activity concentration of 226Ra and 232Th found in TSP fertiliser are 304.57 ± 36.0 and 19.1 ± 6.8 Bq kg−1 respectively and the average activity concentration of 40K in MOP fertiliser is found as 10,311.11 ± 1168 Bq kg−1. In the organic fertiliser samples, the mean concentration of 226Ra, 232Th and 40K are 17.35 ± 3.11, 7.20 ± 1.74 and 437.14 ± 42.58 Bq kg−1, respectively. The mean absorbed dose rates were measured after the end of our experiment, and the value was found to be 91.39 nGy h−1. The combined (indoor + outdoor) annual effective dose equivalent was also estimated as 0.322 mSv year−1. The mean radium equivalent activity found to be 190.15 ± 26.74 Bq kg−1 is well below the recommended level of 370 Bq kg1. The internal hazard index, external hazard index, and radioactivity level index of the investigated fertiliser samples were found as 0.56 ± 0.034, 0.54 ± 0.08 and 0.69 ± 0.10, respectively. From the calculated hazard parameters, the excess lifetime cancer risk (ELCR) was found to be higher than the world average in most of the chemical fertilisers except in DAP and BOR, while the organic fertilisers show lower than the world average. The obtained results reveal that there are no significant radiation hazards due to natural radionuclides of the fertiliser samples in the studied area, but the higher concentration of 40K in MOP suggests strengthening the regulatory work. Overall, this study highly recommends the use of organic fertilisers, as these kinds have hazard parameters lower than the recommended levels. [ABSTRACT FROM AUTHOR]

Natural radionuclide activity concentrations were measured in ceramic, gypsum, and brick samples from manufacturers, dealers, and construction sites in and around Addis Ababa, Ethiopia, using an HPGe detector. The study's main aim is to assess the activity concentration of building materials and their health impacts. Average activity concentrations (Bq kg−1) for 226Ra in ceramic, gypsum, and brick samples were obtained as 81 ± 1, 1.34 ± 0.17, and 39 ± 1, respectively. In ceramic, gypsum, and brick, concentrations of 232Th were obtained as 166 ± 4, 0.68 ± 0.18, and 103 ± 3, respectively, while concentrations of 40K were found to be 755 ± 16,15 ± 1, and 921 ± 24, respectively. Some of the materials that were tested, especially the ceramic samples, had slightly higher concentrations of radionuclides in comparison to other analysed samples. In all samples except ceramic, Raeq was < 370 Bq kg−1, which is the recommended limiting dose for bulk medium. Furthermore, the corresponding radiological parameters, such as absorbed dose, annual effective dose equivalent, excess lifetime cancer risk (ELCR), internal (Hin) and external (Hex) hazard indexes, gamma index (Iγ), and alpha index (Iα) were determined. The ELCR average values in this study are slightly higher than the global average, and the indoor and outdoor absorbed dose rates are greater than the limiting criteria of 84 and 59 n Gy h−1, respectively. Therefore, it is important to assess the potential radiation risk of ceramic samples, which should be used in a controlled manner to reduce gamma exposure to residents. Finally, the computed data could be used as a baseline to assess any future radiation exposure from construction materials. [ABSTRACT FROM AUTHOR]

This work presents a study of radioactivity in soil samples from oil well sites of Baba Gurgur dome of Kirkuk oil field using a high-purity germanium (HPGe) detector and spectroscopy system. The activity concentration (Bq kg−1) of 226Ra, 232Th, 40K and 137Cs varied between 26.4–98, 10.8–55.2, 239–729, and 2.40–7.20, respectively. The results have been compared with the average worldwide values. The hazard indices have also been calculated. The radium equivalent activity (Raeq) was 131.04 Bq kg−1, the absorbed gamma dose rate (D) was 62.04 nGy h−1, the annual effective dose rate (AEDE) outdoor and indoor were 0.08 mSv y−1 and 0.30 mSv y−1, respectively, the external hazard (Hex) was 0.35, the internal hazard (Hin) was 0.51, the Gamma radiation representative level Index (Iγ) was 0.96, and excess lifetime cancer risk was 0.30 × 10−3. Our results of some sites were found to be higher than the allowable worldwide values. Statistical data including: Mean, Median, Std. Deviation, kurtosis, skewness, box plot, frequency distribution, Quantile-quantile (Q-Q) plots, Pearson's correlation coefficient analysis, principal component analysis (PCA), and cluster analysis were calculated and carried out to explain our results. [ABSTRACT FROM AUTHOR]

The Unumherin community in Nigeria's Niger Delta is home to coastal marine polluted zones, and this research examines the radioactivity distributions and biohazard in the coastal environment. The activity concentrations of 40K, 238U, 232Th, as well as the outdoor dose rate of contaminated coastlines were measured using a calibrated RS-125 Gamma-Spec and a NaI(Tl) gamma-detector. The laboratory examination of sediments, water, and fish from the same coastal region -- Clarias gariepinus Pseudotropheus elongated Oreochromis niloticus and Stromateus fiatola -- was combined with the in-situ observations of gamma dose rates. With a value of 100nGy=h, the hotspot at site 4 is shown by the geographic distribution of gamma dose rates. The findings showed that the activities of the primordial radionuclides varied, with average values for the sediments and water exceeding suggested limits. Similarly, the corresponding mean hazard indices mostly exceeds the allowable limits. The species specificity of the fish species accounts for the variation in the mean concentrations of 40K, 238U and 232Th. C. gariepinus, having accumulated higher concentrations of 40K and 238U, may be the first to elicit health hazards in the future if pollution continues unmonitored. Hence, continuous monitoring of the aquatic environment alongside is highly recommended. [ABSTRACT FROM AUTHOR]

A radiological assessment of inland freshwater fishes of wetland haor zones, near a uranium mine and Rooppur Nuclear Power Plant (RNPP) areas, was performed. Gamma spectrometric analysis showed the accumulation of 226Ra, 228Ra, and 40K in all studied fishes, with varying degree levels of concentrations. The average radioactivity levels of 226Ra, 228Ra and 40K in haor fish samples ranged from 2.76 ± 1.51 to 22.02 ± 3.81 Bq kg−1, 1.78 ± 0.69 to 21.53 ± 1.40 Bq kg−1 and 405.51 ± 22.04 to 749.80 ± 42.65 Bq kg−1, respectively. Conversely, the respective values for Bata fish samples of Rooppur Nuclear power plant sites varied from 2.66 ± 0.80 to 6.62 ± 0.81 Bq kg−1, 2.31 ± 0.62 to 5.18 ± 49.81 Bq kg−1 and 342.00 ± 4.98 to 461.45 ± 18.00 Bq kg−1, respectively. Activity levels of Taki fish (Channa punctatus) from haors zones were almost 3–4 times higher than the Meni fish (Nundus nundus) of the same locations and Bata fish (Labeo bata) of the RNPP site. The general public may attain doses of 244.54 µSv from the consumption of haor fish and 84.02 µSv from the fish of the RNPP sites yearly. The chance of an increase in cancer risk from intake of haor fish was higher than the ICRP values of 2.9 × 10−4. Univariate statistics showed that 226Ra and 228Ra radionuclides do not normally distribute, whereas 40K is normally distributed in the studied fish species. Multivariate statistical analysis demonstrated that the radioactivity and estimated radiological parameters are strongly positively correlated with 226Ra and 228Ra, and also positively correlated with 40K. Hence, it indicated that the contents in the freshwater fish species are usually controlled and influenced by similar geogenic sources and occur together. It is presumed that the radiological risk is mostly associated with and dominated by the uranium and thorium series and non-series 40K radionuclides in the freshwater fish species. [ABSTRACT FROM AUTHOR]

Radioactivity in coastal sediments in northern Vietnam was examined using data from five sediment cores to assess radioactivity concentrations and radiation risk indices. Radiation risk indices included radium equivalent activity (Raeq), the absorbed dose rate (ADR), the annual effective dose equivalent (AEDE), the activity utilization index (AUI), the external hazard index (Hex), the representative level gamma index (Iγr), and the annual gonadal effective dose rate (AGDE). The radioactivity concentrations of 40K, 232Th, 226Ra, 238U, and 137Cs were 567, 56.1, 35.1, 37.9, and 1.18 Bq/kg, respectively. The average concentrations of 40K, 232Th, 226Ra, and 238U were above the global average at five sites, except for 137Cs, which was low. The Raeq, Hex, and AUI indices were below the recommended values, while the AEDE, ADR, AGDE, and Iγr indices were above the recommended values. Moreover, 40K, 232Th, 226Ra, and 238U had significant impacts on the radiation hazard indices Raeq, ADR, AEDE, Iγr, AUI, Hex, and AGDE. There are three coastal sediment groups on the northern coast of Vietnam: Group 1 has a higher radioactivity and radiation risk index than Group 2 but a lower value than Group 3. Group 3 had the highest radioactivity and radiation risk index. The values of 40K, 232Th, 226Ra, and 238U and the ADR, AUI, Iγr, and AGDE indices in the sediment threaten the living environment. [ABSTRACT FROM AUTHOR]

All living creatures in nature are constantly exposed to ionising radiation, which is emitted from natural and artificial radiation sources. For this reason, it is important to monitor the levels of radioactivity in living spaces and visited areas. In this study, natural (238U, 232Th, 40K) and artificial (137Cs) radioactivity concentrations in sediment samples taken from Borçka Black Lake located on the Nature Park in Artvin province were determined using a high purity germanium detector (HPGe). It was determined that 238U, 232Th, 40K and 137Cs radioisotope concentrations in the sediment samples varied between 8.73 and 26.45, 7.01 and 22.98, 289.92 and 578.98, and 6.26 and 70.96 Bq kg−1, respectively. Mean radioactivity concentrations were found to be 14.99 ± 0.89 Bq kg−1 for 238U, 13.85 ± 1.10 Bq kg−1 for 232Th, 473.67 ± 14.21 Bq kg−1 for 40K and 35.06 ± 0.96 Bq kg−1 for 137Cs. In order to evaluate the radiological hazards, radium equivalent activity, external hazard index, absorbed dose rate in the air, the annual effective dose rate and excess life time cancer risk were calculated and compared with the values recommended by international organisations. As a result, it has been shown with this study that the radioactivity caused by the examined radioisotopes will not pose any health risk for the visitors of Borçka Black Lake. [ABSTRACT FROM AUTHOR]

Sediment quality can be assessed by analyzing radionuclides and heavy metals from pollution sources. These substances also provide insight into sediment structure and marine pollution. The aim of this study was to evaluate the risk of radiation and heavy metal accumulation in İzmir Bay by taking into account both lithologic and anthropogenic factors. Sediment samples were collected from İzmir Bay on a seasonal basis. Gamma-ray spectrometry techniques were used to determine radionuclides in the sediment using a NaI (Tl) scintillation gamma spectrometer. X-ray fluorescence spectrometry (XRF) was employed to measure heavy metal concentrations in the samples. Mean concentrations of 232Th (43.6 Bq/kg), 226Ra (35.3 Bq/kg), 40K (699.2 Bq/kg), and heavy metals Fe (13408.3 ppm), Al (16891.6 ppm), Mn (517.3 ppm), Zn (59.8 ppm), Cr (96 ppm), Ni (31.6 ppm), and Pb (31.8 ppm) were determined in the surface sediment. The elevated levels of both radionuclides and heavy metals were attributed to industrial accumulation and sedimentation patterns in the bay. The study highlights the importance of considering both geological structures and environmental risks in assessing sediment quality. [ABSTRACT FROM AUTHOR]

This study measured the naturally occurring radionuclides (238U, 232Th, and 40K) in sixteen selected soils samples of Irele local government area in Ondo state, southwestern Nigeria using a thallium-doped sodium iodide gamma-ray spectrometry detector. The values of concentration of natural radionuclides in the soils ranged from 16.18–32.16 with a mean value of 27.58 Bq.kg−1, 10.38–24.15 with a mean value of 16.92 Bq.kg−1, and 321.13–528.18 with a mean value of 423.05 Bq.kg−1 for 238U, 232Th, and 40K, respectively. The values of the assessed radiological parameters (absorbed gamma dose rate in air, annual effective dose rate, radium equivalent activity, and the external hazard index) are found to range from 30.81–47.11 with a mean value of 40.60 nGy.h−1, 0.19–0.29 with a mean value of 0.25 mSv.y−1, 62.53–98.25 with a mean value of 84.35 Bq.kg−1 and 0.17–0.27 with a mean value of 0.23, respectively. The obtained values are lower than the recommended world average of 33, 45, and 450 Bq.kg−1 for 238U, 232Th, and 40K published by the United Nations Scientific Committee on the Effects of Atomic Radiation and the National Council on Radiation Protection and Measurement. [ABSTRACT FROM AUTHOR]

The radiation level, radionuclide distribution, and dependence of radioactivity on physico-chemical parameters of soils have been studied in Belagavi region of Karnataka, India. The gamma dose rates in air were measured using a portable survey metre, and the activity in soils was measured using NaI (Tl)-based gamma ray spectrometer. The measured absorbed dose rate in air ranges from 54 to 77 nGy h−1 with a mean value of 58 nGy h−1. The 40K activity in soil was found to vary from 97.9 to 378.5 Bq kg−1 with an average of 214.2 Bq kg−1. The 226Ra activity varied from 15.3 to 68.8 Bq kg−1 with an average value of 30.5 Bq kg−1 and the activity of 232Th varied from 12.3 to 65.4 Bq kg−1 with an average value of 27.96 Bq kg−1. The activity of 226Ra and 232Th were found to be higher than the world average value in some locations of the study area. A good positive correlation was observed between the activity concentration of radionuclides and physico-chemical parameters of soil. A good positive correlation was observed between the activity of 226Ra and 232Th with clay with a correlation coefficient of r = 0.609 and 0.591, respectively. The frequency distribution curve of 226Ra, 232Th, and 40K are lognormal in nature. The application of cluster analysis and principal component analysis were carried out using IBM SPSS software for better understanding of dynamics of soil matrix and the dependence of soil radioactivity on the physico-chemical parameters of the soil. [ABSTRACT FROM AUTHOR]

To address potential health risks associated with radioactivity in tea consumption, a study was conducted utilizing high purity germanium (HPGe) γ-ray spectrometry to measure the concentrations of 226Ra, 232Th, 40K, and 137Cs radionuclides in soil and tea leaves collected from several major tea gardens (including the Malnicherra tea garden which is the largest and first established tea garden in the Indian subcontinent) situated in Sylhet, Bangladesh. Although nearly all soil samples showed the presence of 137Cs (with a maximum activity of 6.5 ± 1.31 Bq/kg), none of the analyzed tea leaf samples exhibited its presence, which can be attributed to its restricted transferability from soil to plants. The range of transfer factors for 226Ra, 232Th and 40K from soil to tea leaves was calculated to be (0.39–0.54), (0.25–0.46) and (1.39–3.03), respectively. The heightened concentrations of 40K identified in the tea leaf samples can be mainly ascribed to specific metabolic processes associated with potassium, along with the heightened utilization of potassium chloride-based fertilizers aimed at enhancing tea production. The examination of hazard parameters, including the estimated committed effective dose and the excess lifetime cancer risk associated with tea consumption, reveals values that are comparatively lower than the recommended limits. Consequently, the radiation exposure from tea consumption does not present a significant radiological health concern for the general population. [ABSTRACT FROM AUTHOR]

Terrestrial gamma radiation is one of the major outdoor radiation exposures to the general public that varies substantially based on the type and geological properties of the soil. The objective of this study is to evaluate the naturally occurring radioactive materials (NORMs) distribution and assess the hazard parameters in the riverbank soil within various industrial zones in the densely populated Dhaka and Chattogram cities of Bangladesh. The mean activities of 226Ra (37 ± 3), 232Th (58 ± 4), and 40K (1129 ± 18) Bqkg−1 in the assessed soil samples were found to be slightly higher than the world average values 32, 35, and 420 Bqkg−1, respectively. The mean radium equivalent activity (207.49 Bqkg−1) and the external and internal hazard indices were within the recommended limits of 370 Bqkg−1 and <1, respectively. The mean absorbed dose rate (99.47 nGyhr−1), annual effective dose (0.12 mSva−1), ELCR (4.27 × 10−4), and gamma level index (1.58) exceeded the world average values 59 nGyhr−1, 0.07 mSva−1, 2.9 × 10−4, and 1 respectively. However, the studied areas are safe from a radiological viewpoint with no radiation health hazard to the people. The results of this study can be utilized to produce factual baseline data for future studies. [ABSTRACT FROM AUTHOR]

The distribution of natural series radionuclides 226Ra, 232Th and non-series 40K in the heavy mineral-rich beach sands of highly touristic areas of Cox's Bazar sea beach has been studied. The study is made to evaluate the gamma radiation exposure to individuals with an aim to establish reference data for the presence of naturally occurring radionuclides. The present study reports the probable first attempt of detail and systematic work in the study areas for estimation of activity concentration in the recent beach sand samples. Radiometric analysis was performed using gamma ray spectroscopy system based on HPGe detector. The mean activity levels of 226Ra, 232Th and 40K in Laboni beach sands were ranged from 255.69±64.57, 336.83±93.96 and 1785.91±89.60 Bq kg-1, respectively. While in Kolatoli beach sands, the respective values were 166.42±35.99, 157.35±35.90 and 1894.42±74.07Bq kg-1, respectively. The mean values of 226Ra and 232Th concentrations in the investigated beach sands were estimated to be very much higher than the corresponding world average values and comparable to those found in high background radiation areas in the world. The heavy minerals seem to control the activity concentrations of 226Ra and 232Th in sand samples, showing some variances based on uranium and thorium bearing minerals. Various radiation health hazard indicators were found to be extremely higher when compared to the recommended values. Hence, heavy mineral-rich sands may pose a significant radiological health risk to the people. The descriptive statistics indicating the radionuclides of 226Ra, 232Th and 40K are uniformly and symmetrically distributed in the Cox's bazar beach sand. Multivariate statistical analysis showing the radioactivity and estimated radiological parameters are strongly positively correlated with 226Ra and 232Th, while weakly correlated with 40K, signifying that radiological risk is mainly associated and controlled by the radioactivity levels of uranium and thorium series radionuclides. [ABSTRACT FROM AUTHOR]

In this review, the online searchable research articles were scrutinized for the data presented in line with radioactivity and dose estimates from both terrestrial environments and foodstuffs from Bahi district and other parts of Tanzania. The data on natural gamma ray dose rates from Bahi localities were observed with variations among researchers. The observed ranges of radioactivity concentrations (Bq kg−1) in soil were 226Ra (28.5–57.4), 232Th (38.1–521.3), and 40K (562.9–665.0). Deep closed water wells with installed pumps from Ilindi and Bahi Mission reported radioactivity concentration of 238U 3.08 Bq L−1 and Ilindi swamps reported radioactivity concentrations of 226Ra 15.35 Bq L−1, whereas radioactivity concentrations of 238U in cereals were within the annual tolerable limits of 0.001–0.02 Bq kg−1. The quantity and accessibility of published studies, as well as the diversity of the data, point to the necessity for additional studies to be carried out in order to obtain comprehensive baseline data. [ABSTRACT FROM AUTHOR]

The outdoor gamma dose rate was measured in 540 locations in southern regions (Ramanathapuram, Virudhunagar, Tirunelveli, and Thoothukudi) of Tamil Nadu, India. The measured dose rates vary from 35 to 335 nSv/h (mean 89 nSv/h). The observed mean dose rate (89 nSv/h) is 2.3 times higher than the national (India) average of 39 nSv/h (56 nGy/h) and 2.1 times higher than the world average of 41 nSv/h (59 nGy/h). Annual Effective Dose (AED) calculated varies from 0.04 to 0.41 mSv/y (mean 0.11 mSv/y). The mean AED (0.11 mSv/y) is 1.6 times higher than the world average annual effective dose of 0.07 mSv/y. 30% of the locations have higher AED values due to the higher radiation in that locations. The present study reveals that the Tirunelveli district of the southern Tamilnadu region has higher gamma radiation than the other four districts of this region and is due to the topography of coastal and mountainous areas in Tirunelveli. The higher gamma radiation dose in the study area is due to the radionuclides present in the mountainous region's rocks and the coastal regions' soils. The radiological maps were used for spatial interpretation of the outdoor gamma dose rate in the study area. The radiological cancer risk assessment reveals that the Tirunelveli district has a higher risk due to the higher background gamma radiation. [ABSTRACT FROM AUTHOR]

The contamination density of 137Cs deposited in the gap between the top and middle covers of the shield plug in the Fukushima Daiichi Nuclear Power Station Unit 2 was estimated using three types of measurement results. Owing to the extremely high dose rate on the entire operation floor, including the top of the shield plug, only remotely measured dose rates, such as ambient dose equivalent rates, were obtained using robots. Based on three types of measurements, significantly higher concentrations of 137Cs were observed than previously estimated. An estimation based on the measurements of the ambient dose equivalent rate inside the hole also demonstrated that the contamination density in the gap between the top and middle covers varied significantly at different positions of the cover. The results obtained will significantly aid in future decommissioning scenarios, and will be important for examining the progress of an accident. [ABSTRACT FROM AUTHOR]

At high-energy accelerator facilities like the ones that are part of the accelerator complex at the European Organization for Nuclear Research (CERN), Monte Carlo radiation transport codes are widely employed to face the challenges of estimating radionuclide production yields and activities with the aim of performing the radiological characterization of activated components. Indeed, it is of paramount importance to ensure adequate radiation protection during scheduled maintenance, transport, and handling of these components and to establish their proper disposal pathway once they ultimately reach the end of their useful life. This paper summarizes the principles of the fluence conversion coefficients method that was developed as a complementary approach for radiological characterization studies. Then, the Monte Carlo simulations in preparation to the pilot beam run at the Large Hadron Collider at CERN in 2021 are presented as a practical example of possible applications. Finally, the flexibility of the method and the most relevant operational radiation protection implications are discussed in relation to the provided example. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The specific activities of natural radionuclides, 232Th, 226Ra, and 40K, in a Chinese iron beneficiation plant and surrounding soil were analyzed with the high purity germanium gamma (HPGe) spectrometer in this study. Average specific activities of 238U, 232Th, 226Ra and 40K lower than the Chinese averages. To assess radiation impact, various indicators, radium equivalent index (Raeq), absorbed dose rate (DR), annual effective dose (AED), excess lifetime cancer risk (ELCR), external hazard index (Hex), internal hazard index (Hin) and activity utilization index (AUI), were calculated. Mean values were below international limits, indicating no significant health hazards for the local population. Statistical analyses, including skewness and kurtosis calculations, along with techniques like frequency distribution, Pearson's correlation analysis, box plots and cluster analysis, were applied to comprehensively assess distribution patterns and interrelationships among radiological parameters. In summary, there are no potential health hazards associated with the soil in the study region for people. [ABSTRACT FROM AUTHOR]

The new coronavirus pandemic (2019-nCoV) arrived in Brazil in February 2020, where the worsening led to social isolation. The population started to remain entirely in their homes, mainly the elderly, children, and adolescents. The study aimed to determine the impact of radioecological dosimetry within the residences located in the municipality from Espinharas, Paraíba, Brazil, where one of the main uranium deposits in Brazil occurs. A scintillator-type gamma spectrometer with a combined NaI (Tl) and BGO probe, at 1.0 m from the soil surface, was used. A total occupation factor for the pandemic period was considered. The dose-response for the three months ranged from 0.55 to 1.70 mSv, with an average of 0.68 mSv, which characterises an increase of 25% when compared to the same period of the retrospective study in 2014. In the period of one year, the dosimetric response can vary between 2.22 and 6.80 mSv/y, with an average of 2.73 mSv/y. The work portrays the importance of a database for future affirmative actions and the determination of different radiometric conditions in an environment already considered to have a high level of natural radioactivity. The study also provides definitions of extreme exposure conditions and correlations with public health parameters. [ABSTRACT FROM AUTHOR]

This study examined the radioactivity levels of soil samples within selected solid mining sites in Nigeria using high-purity germanium (HpGe) detector. Sixty soil samples in all were collected from the 10 solid mineral mining sites investigated and six samples were collected as control samples from non-mining environment for analyses. The results of the activity concentration values obtained for 40K, 226Ra and 232Th are 100.22 Bq kg−1, 33.15 Bq kg−1 and 77.31 Bq kg−1, respectively. The 226Ra and 40K activities were found to be within the United Nation Scientific Committee on the Effects of Atomic Radiation acceptable permissible limit, but the 232Th mean value was above the permissible limit of 30 Bq kg−1 for the public. In comparison, 40K, 226Ra and 232Th soil samples mean activity concentrations were higher than the control soil samples values by 48.6%, 43.7% and 62.3%, respectively. The results of estimated radiation hazard indices indicate average values of 150.72 Bq kg−1, 68.40 nGyh−1 n G y h − 1 , 83.65 µSvy−1 and 454.70 µSvy−1 for the Radium Equivalent (Raeq R a e q ), Absorbed Dose Rate (D), Dose Equivalent (AEDE) and Annual Gonadal Equivalent Dose (AGED), respectively. The mean values for External Hazard Indices (Hex, Hin), Representative Gamma index ( I γ ) and Excess Life Cancer Risk (ELCR) were 0.41, 0.50, 1.06 and 0.29 × 10−3, respectively. The statistical analysis shows positive skewness. [ABSTRACT FROM AUTHOR]

The Karnaphuli and Halda rivers play a significant role in the ecological and commercial arena of Bangladesh, but no detailed study on radioactivity in these two rivers sediments is reported elsewhere. The present study measures the concentrations of terrestrial radionuclides in the sediment samples collected from these two rivers by using high-purity germanium (HPGe) γ-ray spectrometry. The concentrations (Bqkg−1) of 226Ra, 232Th and 40K show in the range of 17.63 ± 1.47–38.90 ± 2.50, 27.86 ± 1.76–48.80 ± 2.70 and 324.28 ± 26.83–640.70 ± 42.70, respectively, which is similar to the literature data and world mean value except for four sampling locations (Kalamiabazar, Natun bridge, Rajakhali and Chaktai khal) that shows higher concentrations of primordial radionuclides. These four sampling points are located adjacent to the industrial wastes discharge channels into the Karnaphuli river. In fact, among the thousands of industries located on the bank of the Karnaphuli river, about 200 units were identified as the sources of environmental pollution. To assess human health hazards due to natural radiation, several indicators such as radium equivalent activity (Raeq), external hazard index (Hex) and outdoor annual effective dose equivalent were calculated and compared with the recommended limits. The present results serve as an input to prepare the baseline radioactivity in commercially important river sediments prior to the operation of the first nuclear power plant in the country. [ABSTRACT FROM AUTHOR]

Bentonite is a soft, porous, easily shaped, and absorbent material rich in aluminum, sodium, and potassium. Bentonite is a mineral widely utilized as drilling mud, ore pelletizing, absorbent/adsorbent, bleaching agent, water impedance, coating, and raw material in various industries. In this study, radiometric measurements of 90 bentonite samples collected from 21 quarries in Turkey were performed using gamma-ray spectrometry. The radiological hazards caused by indoor exposure to adults due to the utilization of bentonites as raw materials in the construction industry and outdoor external exposures to quarry workers were evaluated by estimating the activity concentration index, annual effective doses, and lifetime cancer risk. The average activity concentrations of 226Ra, 232Th and 40K measured in bentonite samples were found as (50 ± 5) Bq/kg, (76 ± 4) Bq/kg and (373 ± 19) Bq/kg, respectively. The evaluation results reveal that the bentonites examined could be safely utilized as raw materials. [ABSTRACT FROM AUTHOR]

Radionuclides 226Ra, 232Th, and 40K can be found in various concentrations in the surface soil. High concentrations of radionuclides in the surface soil may cause radiological risks. This study investigated natural radioactivity levels and artificial radionuclide (137Cs) levels in the Istanbul University-Cerrahpasa, Avcilar region, Istanbul, Turkey. Radioactivity concentrations were analyzed using the gamma-ray spectrometer. The mean activity concentration of 226Ra, 232Th, 40K, and 137Cs is 28.55, 29.57, 385.72, and 3.09 Bq kg−1, respectively. Radiological parameters radium equivalent activity, absorbed dose rate, annual effective dose equivalent, external hazard index, and excess lifetime cancer risk were calculated using activity concentrations. The radiological parameters values were lower than UNSCEAR values, except for the annual gonadal dose equivalent (approximately 10% higher). There is a strong correlation between radiological parameters and radionuclides. Generally, the activities of radionuclides in the region fall within the recommended limits, thus Istanbul-Avcilar region can be considered safe for settlement. [ABSTRACT FROM AUTHOR]

The concentration of natural and anthropogenic radionuclides, emanation fraction (EF), and mass (χM) and area (χA) exhalation rate of 222Rn in urban soil samples collected from dwelling areas in Nevşehir city located in a region known as the central Anatolian volcanic province of Turkey were determined using gamma-ray spectroscopy. The average activity concentrations of 226Ra, 228Ra, 40K and 137Cs were measured as 60.2 ± 3.8, 50.1 ± 2.8, 631.0 ± 29.7 and 5.5 ± 0.4 Bq/kg, respectively. The average concentration of 222Rn in soil and air was estimated as 27 kBq/m3 and 84 Bq/m3, respectively. The average values of EF, χM and χA were found as 20%, 25.4 μBq/kg⋅s and 20.2 mBq/m2⋅s, respectively. The average values of outdoor absorbed gamma dose rate, external and internal annual effective dose and lifetime cancer risk estimated for radiological assessment were found as 85 nGy/h, 104 µSv/y, 797 µSv/y and 4.1 × 10−4, respectively. [ABSTRACT FROM AUTHOR]

Accurate knowledge of the terrestrial radionuclides concentrations in building components is crucial for radiation exposure assessment to the dwellers. The present investigation determines the natural radioactivity levels in common building materials (the structural and decorative) used in Bangladeshi dwellings via HPGe gamma-ray spectrometry. The measured activity levels of 226Ra, 232Th and 40K in the studied materials ranged between 7.33 ± 3.49 and 157.13 ± 13.03 Bq kg−1, 4.08 ± 1.84 and 131.65 ± 6.87 Bq kg−1 and 128.38 ± 10.27 and 1234.5 ± 39.77 Bq kg−1, respectively. Majority of the studied materials, especially the cement and paint, show the elevated concentrations of terrestrial radionuclides. However, for most of the samples, the total activity in terms of hazardous radium, show lower values compared to the OECD reported limiting index of 370 Bq kg−1, except in paint samples. The potential radiological hazards owing to the investigated samples were assessed by calculating a number established screening parameters, and compared with the agreed limits set by international regulatory bodies. The calculated indoor and outdoor absorbed dose rates for most of the materials (apart from sand) overdo the agreeing limiting standards of 84 and 59 nGy h−1, as suggested by UNSCEAR (2000). Therefore, continuous radiation level monitoring, especially for paint and cement samples, need to be continued to avoid undesirable exposure from radiation to occupants. Overall, the calculated data may help to set up recommendations for using building materials for dwelling resolutions. [ABSTRACT FROM AUTHOR]

In this study, the activity concentrations of natural and artificial radionuclides in 18 sediment samples were investigated from Iraq's Upper and Lower Dukan Dam using the high-purity germanium (HPGe) detector as a gamma-ray spectrometry technique. The results revealed that the values of the activity concentration of 226Ra, 232Th, 40K, and 137Cs sediment ranged from (2.85–24.60 Bq kg−1), (1.27–7.56 Bq kg−1), (42.14–346.60 Bq kg−1), and (0.14–3.62 Bq kg−1), respectively. The radiological risk parameters such as radium equivalent activity, absorbed dose rate, annual effective dose equivalent, and external hazard index were determined and found to be 30.98 Bq kg−1, 14.97 nGy h−1, 29.62 nGy h−1, 0.019 mSv y−1, 0.153 mSv y−1, 0.08, and 0.11, respectively. The observed mean values were comparable to internationally recommended values. The field dose rates were measured using the RIIDEye Handheld Radiation Isotope Identifier, and the range was 23.5 nsv h−1–80.6 nsv h−1. The data obtained in this study can be used as a baseline for future investigations of radioactivity background in the investigated area. [ABSTRACT FROM AUTHOR]

The present article aims to assess environmental impact coming from terrestrial natural radionuclides, external gamma exposure dose radiation and the average effective annual dose value. The obtained data can be used to provide technical support for the social communication of nuclear energy bodies to understand the natural radiation background of the study area. To achieve the aim, 11271 measurements of 238U, 232Th and 40K were carried out using airborne gamma ray spectrometry for the study area. These measurements were used and converted in to specific activity for calculating the absorbed dose rate (D) and the annual effective dose (E) to infer the average annual effective dose value for the population of Abu Zenima area. The calculated specific activity of U238, Th232 and K40, absorbed dose rate, annual effective dose rate, collective dose and annual effective dose value for the population were mapped through Geographic Information System (GIS) using Arc map software version 10.5. The specific activity concentration of U238 ranged from 1 to 400 Bq/kg, Th232 ranged from 1 to 650 Bq/kg and K40 ranges from 1 to 4000 Bq/kg. The absorbed dose rate values ranged from 3.25nGy/h to 261 nGy/h. Annual effective dose rate values, varying from 21 to 9867 µSv y−1 with an average value of 172µSv y−1which is higher than the worldwide average value of 70µSv y−1 (for outdoor exposures from terrestrial radiation sources).The collective effective average dose (S), varied from 1.16 to 424.31 with an average value of 20.77 man mSv. Finally, average total population effective dose of Abu Zenima area ranged from 0.0013 to 0.0375 with an average value of 0.0129mSv. From all these results, it was concluded that Al Sahu, Al Nasb, Serabit El Khadim and Al Lehianlocalities have high background radiation. [ABSTRACT FROM AUTHOR]

Radium-226 detection in sediment samples is generally executed by means of gamma-ray spectrometry. Data evaluation relies (besides the 186.2 keV 226Ra gamma peak) on the combined analysis of major gamma peaks that are produced by the short-lived radon (222Rn) daughters 214Pb and 214Bi. Precondition for this detection approach is equilibrium decay of all members of the decay chain between 226Ra and 214Bi. In closed systems, this equilibrium is reached after about five half-lives of 222Rn (19 days). However, a closed system can only be guaranteed if the capsule which contains the sample prevents diffusive escape of radon. Such radon-tightness cannot be guaranteed for a wide range of plastic materials. Due to its polymer structure, plastic material generally tends to allow radon diffusion and hence radon loss from the sample resulting in a disturbance of the required decay equilibrium. The paper introduces an approach that allows quantifying radon loss from sample capsules by direct radon measurements using mobile radon detection equipment. The experimental findings are supported by theoretical considerations. An examined alternative approach based on the offset of the 186.2 keV data point from an efficiency function that is calculated exclusively from short-lived radon progeny peaks in the gamma-ray spectrum did not prove to be applicable due to a lack of supporting peaks in the low-energy section of the spectrum. [ABSTRACT FROM AUTHOR]

Natural environmental radioactivity aroused mainly from primordial radionuclides such as 40K and 238U and 232Th decay series, and have been present in varying concentrations within the earth and in the tissue of every living being. Natural radioactivity can be found everywhere; in the soil, public water supplies, oil, and the atmosphere and it poses a measurable exposure to human beings. The present study developed a statistical model that can be used to predict the Terrestrial Gamma Radiation Dose rates (TGRD) based on soil types and geological formations irrespective of the environment. About 295 TGRD measurements were taken using a micro-Roentgen survey meter (model 19) manufactured by Ludlum, from different locations within the study area. Statistical Package for Social Sciences (SPSS) was utilized in establishing the relationships between TGRD with underlying geological formations and soil types as well as in the development of the model. The developed model was tested by predicting the TGRD value over different combinations of soil types and geological formations, and it was found to fit in well with more than 80% degree of accuracy which is within the acceptable limit. The developed model in this study, may help in establishing the background radioactivity levels in a terrestrial environment that can be used to evaluate any changes that may arise as a result of any release due to both natural and or human activities in a certain area. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine the natural radioactivity levels and evaluate the radiological hazard in vegetable samples collected from Kirkuk city by using gamma-ray spectrometer HPGe. The results show that the highest specific activity of 226Ra and 232Th in vegetables was (9.65, 7.9) Bq.kg–1 in Vg27 (Root/Garlic) while, the highest specific activity of 40K was (221.08 Bq.kg–1 in Vg37 (Leguminous/kidney bean), respectively. The results show that the average specific activities in vegetable samples for 226Ra and 232Th, and 40K was (6.119, 4.763 and 135.595) Bq.kg–1, respectively, these results were found to be below natural radiation exposure reported by UNSCEAR, radium equivalent activity (Raeq) were varied from maximum value (30.345 Bq.kg–1 in Vg15 (Leafy/coriander leaves)) to minimum value 13.002 Bq.kg–1 in Vg37 (Leguminous/kidney bean)) with average value 23.371 Bq.kg–1, the total average annual effective dose in vegetable samples for adults, children (10 years old) and infants are estimated to be (60.487, 128.090 and 170.431 μSvy–1), respectively, than those below the WHO permissible limit of 0.3 m μSvy–1. The calculated values of external and internal hazard index in the samples which were lower than the worldwide average value 1, respectively; therefore, these values are found to be safe. The level of radioactivity concentrations in vegetables was determined to ensure consumer safety and the results provide useful information to assess the dose emitted from this radioactivity due to ingestion of these vegetables. This study is very important to investigate the level of radioactivity of vegetables and the findings of this study will useful to determine a baseline of radioactivity exposure to the human from ingestion of vegetables. [ABSTRACT FROM AUTHOR]

Morpholine (MOR) has a broad spectrum of use and represents high risk of human exposure. Ingested MOR can undergo endogenous N-nitrosation in the presence of nitrosating agents forming N-nitrosomorpholine (NMOR), classified as possible human carcinogen by the International Agency for Research on Cancer. In this study, we evaluated the MOR toxicokinetics in six groups of male Sprague-Dawley rats orally exposed to 14C-radiolabelled MOR and NaNO2. The major urinary metabolite of MOR, N-nitrosohydroxyethylglycine (NHEG), was measured through HPLC as an index of endogenous N-nitrosation. Mass balance and toxicokinetic profile of MOR were determined by measuring radioactivity in blood/plasma and excreta. MOR reached maximum blood concentration 30 minutes after administration. Elimination rate was rapid (70% in 8h). Most of the radioactivity was excreted in the urine (80.9 ± 0.5%) and unchanged 14C-MOR was the main compound excreted in the urine (84% of the dose recovered). 5.8% of MOR is not absorbed and/or was not recovered. Endogenous nitrosation of MOR was demonstrated by the detection of NHEG. The maximum conversion rate found was 13.3 ± 1.2% and seems to be impacted by the MOR/NaNO2 ratio. These results help refining our knowledge of the endogenous production of NMOR, a possible human carcinogen. [ABSTRACT FROM AUTHOR]

In the present work, radioactivity level in 15 collected soil samples from the area around fertiliser factory in Upper Egypt has been measured using gamma ray Spectrometry due to radionuclides occurred naturally namely 226Ra, 232Th and 40K to study the concentrations of these nuclides in this soil and determine the effect of Assuit fertiliser factory exhaust on radiological contents of surrounding Soil Samples in Assuit Province, Egypt. Activity concentrations of 226Ra, 232Th and 40K for soil samples were measured by scintillation detector NaI (Tl), has recorded average values 49.45 ± 5.04, 59.113 ± 2.96 and 137.85 ± 6.89 Bq/kg, respectively. On the other hand the average value of radiological hazards affected on farmers and populations were 150.32 Bq/kg, 64.3 nG/h, 0.257, 0.544, 1.006, 0.246, 0.315 and 0.0788 mSv/y for radium equivalent activity, absorbed gamma dose, external and internal hazard indices, gamma index, indoor and outdoor effective dose, respectively. The absorbed dose, gamma index and the annual gonadal dose equivalent the radiological hazards were found higher than permissible level. [ABSTRACT FROM AUTHOR]

This meta-analysis was designed for examining the relative clinical safety and efficacy of normal stent (NS) and radioactive stent (RS) insertion in malignant hilar obstruction (MHO) patients. Relevant studies published as of March 2022 were identified through searches of the Medline, Embase, Wanfang, and CNKI databases, and the pooled results of these studies were then analyzed. Eight studies including 258 and 247 patients that underwent NS and RS insertion, respectively, were incorporated into this meta-analysis. RS insertion was found to be associated with significant improvements in functional successful rate (p = 0.04), Δaspertate aminotransferase (AST, p = 0.0004), Δalanine aminotransferase (ALT, p = 0.002), stent patency (p < 0.00001), stent re-obstruction rate (p = 0.03), and OS (p < 0.00001) outcomes as compared to those associated with NS insertion. No differences in Δtotal bilirubin (TBIL, p = 0.38), cholangeitis rate (p = 0.45), cholecystitis rate (p = 0.84), or hemorrhage rate (p = 0.87) were observed when comparing patients that underwent RS and NS insertion. Substantial publication bias was observed for endpoints of cholecystitis and hemorrhage. These results suggest that relative to NS insertion, RS insertion can effectively prolong stent patency and OS in MHO cases. [ABSTRACT FROM AUTHOR]

This work attempts to identify the latent factors controlling the hydrogeochemistry and assess the groundwater quality and associated health risks in the intermontane valley of Nalagarh in the sub-Himalayan zone in northern India. Analytical results of 64 groundwater samples, 32 each collected during pre monsoon and post monsoon seasons show contrasting results for their major chemical constituents. During pre monsoon period, only 3% of the samples exceed their permissible limits for pH, EC, TH and Mg2+, while during post monsoon period, different parameters, such as TH, Mg2+ and K+, exceed their limits by 9, 16, and 3%, respectively. Gibbs and Piper diagrams reveal that groundwater chemistry is mainly controlled by water-sediment (alluvial) interaction. Geochemical signatures and saturation index (SI) further indicate that the weathering and dissolution of silicate, calcite and dolomite minerals mainly contributed to dominance of Ca2+, Mg2+ and HCO3- ions in the aquifers. Monte Carlo simulation ascertains non-carcinogenic health risks due to NO3− and F− in different sub-population groups. Deterministic and probabilistic estimates of these parameters via ingestion and dermal routes confirm their percentage hazard toxicity in the order infants (58.38; 39.62%) >children (15.62; 15.85%) >teens (6.25; 2.73%) >adults (6.25; 1.90%) for pre monsoon. The hazard toxicity for deterministic study implies only on infants (9.38%), whereas, the probabilistic simulation extracted the health risk on infants (6.57%), and children (0.58%) during post monsoon. Minor populations with their lower body weights are more vulnerable to groundwater pollution due to greater consumption of liquid diet. Therefore, treated groundwater is strongly recommended to mitigate health morbidities linked with the non-cancerous risks. [ABSTRACT FROM AUTHOR]

Cimetidine at a clinical dosage decreased the renal clearance (CLr) of mirogabalin in humans by inhibition of renal secretion. Mirogabalin is a substrate of human OAT1/3, OCT2, MATE1 and/or MATE2-K. To clarify the mechanism behind the above interaction, it was investigated whether cimetidine inhibits the process of mirogabalin uptake at the basolateral side or the process of its efflux at the apical side in rat kidney in vivo. Cimetidine was administered to rats by a constant infusion to achieve an unbound plasma concentration of 7.0 μM and examine its effect on the renal disposition of [14C]metformin, [3H]p-aminohippuric acid (PAH), and [14C]mirogabalin. Cimetidine significantly induced the intrarenal accumulation of radioactivity (Kp, kidney) and decreased the renal clearance (CLr) of [14C]mirogabalin. These effects resulted in significantly decreased total clearance (CLt). Kp, kidney, and CLr of [14C]metformin, except CLt, were also affected, but no parameters of [3H]PAH were affected by cimetidine. These findings clarified that an unbound plasma concentration of cimetidine of 7.0 μM inhibited the apical efflux not the basolateral uptake of [14C]mirogabalin in rat kidney, suggesting that mirogabalin/cimetidine interaction was caused by inhibiting the apical efflux transporter, human MATE1 and/or MATE2-K, not the basolateral uptake transporter, human OCT2, in the kidney. [ABSTRACT FROM AUTHOR]

SHR0302, a selective JAK1 inhibitor developed by Jiangsu Hengrui Pharmaceutical Co., was intended for the treatment of rheumatoid arthritis. In this study, we evaluated the pharmacokinetics, mass balance, and metabolism of SHR0302 in six healthy Chinese male subjects after a single 8 mg (80 µCi) oral dose of [14C]SHR0302. SHR0302 was absorbed rapidly (Tmax = 0.505 h), and the average t1/2 of the SHR0302-related components in plasma was approximately 9.18 h. After an oral dose was administered, the average cumulative excretion of the radioactive components was 100.56% ± 1.51%, including 60.95% ± 11.62% in urine and 39.61% ± 10.52% in faeces. A total of 16 metabolites were identified. In plasma, the parent drug SHR0302 accounted for 90.42% of the total plasma radioactivity. In urine, SHR161279 was the main metabolite, accounting for 33.61% of the dose, whereas the parent drug SHR0302 only accounted for 5.1% of the dose. In faeces, the parent drug SHR0302 accounted for 23.73% of the dose, and SHR161279 was the significant metabolite, accounting for 5.67% of the dose. In conclusion, SHR0302-related radioactivity was mainly excreted through urine (60.95%) and secondarily through faeces (39.61%). The metabolic reaction of SHR0302 in the human body is mainly through mono-oxidation and glucuronidation. The main metabolic location of SHR0302 in the human body is the pyrrolopyrimidine ring. [ABSTRACT FROM AUTHOR]

To evaluate the effectiveness of potassium (K) application in mitigating137Cs transfer from soil to plants, several vegetable species were cultivated under field and pot experiments. In the field experiment, squash, sweet potato, turnip, potato, and carrot were examined in 2020 and 2021 in two different areas of Hamadori (coastal region in Fukushima Prefecture). Transfer factor (TF) was calculated by dividing harvest radioactivity (Bq kg−1 dry or fresh) to soil radioactivity (Bq kg−1 dry) and was negatively correlated with the amount of exchangeable K (ExK) at harvest, regardless of the species, year, and location. In the pot experiment, edamame (immature soybean seed), spinach, turnip, and komatsuna were cultivated, and it was confirmed that ExK was the most powerful factor in regulating TF. Based on the relationship between ExK and TF for each vegetable species, the amount of ExK required to keep the 137Cs concentration lower than a certain level (standard limitation value and one-quarter of that value) was calculated. [ABSTRACT FROM AUTHOR]

More than three quarters of the dose from ionizing radiation is caused by natural radiation sources. In most European countries, groundwater is used as a source of drinking water, what can be an additional source of radiation since naturally occurring radionuclides in the bedrock can dissolve into groundwater. Although the Directive 2013/51/EURATOM establishes several parametric and screening values for different radioactivity parameters, there is a lack of harmonized information and publications available that evaluate the overall condition of drinking water in EU. Thereby, it is challenging to uniformly assess the current situation in European countries in regards of effective doses caused by the consumption of drinking water. This paper aims to collect the available information on the main radionuclides of interest in drinking waters of different European countries and create an overview of the existing situation. [ABSTRACT FROM AUTHOR]

The European Approach The development of airborne radioactivity monitoring ran parallel to the nuclear history of the continent and the need to protect citizens against the possible risks of radioactivity. Monitoring of radioactivity in air is an obligation for European Union (EU) member states following the Euratom Treaty. The dispersion of high amounts of radionuclides all over Europe in April 1986 made it painfully evident that environmental radioactivity monitoring in Europe could be vastly improved. Many laboratories and research groups from both universities and national monitoring laboratories are involved in measuring radioactivity in air. [Extracted from the article]

The radioactive contamination has been reported frequently from agricultural lands and ground water. The main reason behind the radioactive pollution is unprotected mining of radioactive elements, unsafe discard of nuclear industrial waste, military applications, dumping of medically used radioisotopes, globally situated (>400) nuclear power plants and use of phosphate fertilizers in farming. Radionuclides are well known potent carcinogens that may cause the various types of cancers to human and animals due to the long exposure to radioactive contaminated sites. To get rid of from the radioactive pollution there is a need of practically successful and cost effective bioremediation technologies that should able to decontaminate the effected lands and water to benefit the mankind. Microbial and phytoremediation are well studied methods for decreasing or gradually eliminating the radioactive contaminants. In this review, we discussed the different strategies of microbial and phytoremediation of radionuclides and recent advancements, that can play the major role in bioremediation of soil and water. Different remediation technologies based on physical (precipitation, extraction and membrane separation technologies) and chemical (chemical extraction and leaching, hydrolysis, etc.) methods to remediate the radioactive compounds from soils and water are being developed and evaluated. Most of these technologies are cost intensive and only applicable to little contaminated sites. On the other hand phytoremediation and microbial bioremediation are scientifically proven for applying at large scale and economical. Phytoremediation is one of the bioengineering treatments in which terrestrial and aquatic plants have been successfully used for cleaning the radioactive pollutants from diverse environments. Present review article is a updating the recent developments came in the different bioremediation methods. Moreover aim of this manuscript is also emerging the research gaps and identified the future research frontiers to unlock the complexity of phyto and microbial remediation advancements. Although several plants and numerous bacteria and fungi have been identified as the potential radioactive accumulator but their complete mechanism of bioremediation is still unknown. Present article will help the researchers to understand the process of bioremediation of radionuclides in more depths and will aware about the requirements of the coming future. Phyto and microbial bioremediation of radioactive elements, possibilities and challenges. Causes of radioactive contamination in soil and water. Nanophytoremediation is an advanced technology of phytoremediation. Drawbacks of phytoremediation. [ABSTRACT FROM AUTHOR]

Mined Trona is a naturally occurring inorganic salt that is consumed by humans for diverse purposes in Nigeria. Due to the increase in consumption rates of these salts following a renewed government interest in solid minerals exploration and exploitation, it is imperative to assay its radiological content. Reconnaissance survey revealed that the most commonly used Trona varieties were: Farar Kanwa, Jan Kanwa, Dan Libya, Ngurnu, Manda, Farar Balma, Jar Balma and Yar Agadez. Samples of the identified Trona varieties were purchased from markets within Zaria, Nigeria. The samples were analysed using NaI (Tl) gamma ray spectrometry system. Radium equivalent activity (Raeq), annual effective dose (AED), Internal and Alpha hazard Indices (Hin and Iα) and total cancer risks (TCR) were used to assess the radiological safety of its consumption. The activity concentration of 238U (226Ra); 232Th and 40K varied widely and had an average ± error values of 42.904 ± 4.54 Bq/kg, 11.96 ± 1.41 Bq/kg and 455.28 ± 10.56 Bq/kg respectively. Raeq, AED, Iα, Hin and TCR were estimated at 95.07 ± 63.10 Bq/kg, 68.52 ± 52.53µSv/y, 0.21 ± 0.23, 0.37 ± 0.27 and (390.57 ± 299.44) × 10 − 06 respectively; which were by far less than the US EPA and UN SCEAR acceptable thresholds. It was established that the threshold consumption rate is 40 Kg/year and any value slightly higher than the threshold values will be associated with a significant radiological health risk. Therefore, at the present consumption rate of Trona in Nigeria, there is no cause for radiological concern. [ABSTRACT FROM AUTHOR]