Isotopes in Environmental and Health Studies最新文献

Radon (²²²Rn), a naturally occurring radioactive gas, is the byproduct of the uranium decay series. As a naturally radioactive gas, radon is frequently used as a geophysical tracer to find underground faults and geological formations, in uranium surveys, and to forecast seismic events. Abnormalities in radon time-series (RTS) data have been studied before seismic events, indicating that it may act as an earthquake precursor. This paper examined complex RTS with various climatological factors, viz. temperature, pressure and humidity, to extract relevant meaningful physical information by employing various simulation techniques. By employing wavelet-based regression (WBR) on RTS data, radon exhibits linear behaviour with temperature, but non-linear behaviour is observed with pressure and humidity. The anomalies in RTS were found before the seismic events. Multiple linear regression (MLR) also shows the positive relationship of radon with pressure and humidity. The autoregressive integrated moving average (ARIMA) model is utilized to analyse patterns, trends and stationarity in RTS data and predict it over a specified period. The method focuses on selecting the optimal model for predicting radon concentration over an uncertain period. This is done by identifying the one model with the lowest Akaike information criterion (AIC) and the Bayesian information criterion (BIC) values. The experimental results indicate that the ARIMA model outperforms others in predicting radon concentrations over an extended period. This research work not only contributes to the domain of earthquake precursors but also aligns with United Nations SDG 3 by understanding environmental health factors. Moreover, SDG 9 applies advanced technologies for infrastructure safety, and SDG 13 enhances disaster risk reduction and seismic resilience.

This pioneering study assesses the radiological risk of naturally occurring radionuclides in soil around the Bheramara 410 MW Combined Cycle Power Plant (natural gas and high-speed diesel) in Kushtia, Bangladesh. Thirty soil samples were collected at radial distances of 50 m, 500 m, 1000 m, and 3000 m from the plant, these distances were strategically selected to represent immediate proximity (50 m), near-field (500 m), mid-range (1000 m), and far-field (3000 m) zones, enabling a gradient analysis of potential radiological impact. Using high-purity germanium (HPGe) gamma-ray spectrometry, the activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K were found to range from 20 ± 2 to 28 ± 3 Bq/kg, 25 ± 2 to 41 ± 4 Bq/kg, and 310 ± 21 to 440 ± 34 Bq/kg, respectively. While ²²⁶Ra concentrations were below the global average (30 Bq/kg), some measured values of ²³²Th exceeded the global average of 35 Bq/kg, and ⁴⁰K concentrations in certain samples were higher than the global average of 400 Bq/kg. No detectable ¹³⁷Cs was observed, confirming no artificial contamination. Radiological hazard indices such as radium equivalent activity (mean: 100.60 Bq/kg), outdoor absorbed dose rate (mean: 48.56 nGy/h), outdoor annual effective dose (mean: 0.06 mSv/year), external hazard index (mean: 0.27), gamma representative level index (mean: 0.74), and excess lifetime cancer risk (mean: 0.22 × 10^-3) were all within recommended safety limits. Various statistical analyses, including descriptive statistics, Pearson correlation, principal component analysis (PCA), and hierarchical cluster analysis (HCA), were performed and these revealed that ²²⁶Ra and ²³²Th were the main contributors to radiological risk, while ⁴⁰K showed weaker associations. The findings suggest that the soil is safe for agricultural and construction use, but routine monitoring is recommended to ensure environmental protection. This study provides essential baseline data and analytical insight into radiological risk management in power generation industrial regions of Bangladesh.

In recent years, climate change-induced drought has increasingly led to water shortages for domestic and industrial use in Dong Nai Province, Vietnam. Within this province, the Tri An hydropower reservoir plays a crucial role in the sustainability of regional water resources. This study aims to assess groundwater recharge mechanisms in the lower Tri An hydropower reservoir (LTAHR) region using isotopic technique based on the water stable isotope ratios (δD and δ¹⁸O) in groundwater, surface water and local precipitation. The results obtained indicate that the stable isotope values of precipitation in the region exhibit significant seasonal variations, whereas that values of surface water in the reservoir maintains more stability. On the other hand, stable isotopic compositions in groundwater are significantly influenced by monsoonal activity and temperature fluctuations. Applying the end-member mixing analysis (EMMA) method, the study revealed that surface water is the primary contributor to groundwater recharge, accounting for 60-85 %, while precipitation contributes 15-40 %, depending upon the season. Thus, the change of water storage level in the Tri An hydropower reservoir, along with the impacts of El Niño and climate variability, may disrupt seasonal water balance and significantly reduce annual groundwater recharge.

This study provides a radiological evaluation of commonly used pediatric medications obtained from pharmacies in Erbil, focusing on the measurement of naturally occurring radionuclides-²²²Rn, ²²⁶Ra, and ²³⁸U-and the associated internal exposure concerns. The investigation quantified radionuclide concentrations and assessed dose-related parameters, including dose rate, annual effective dose (AED), average annual internal effective dose (AAIED), and health hazard indices such as excess lifetime cancer risk (ELCR) and risk of an excess cancer fatality per million persons (RECFPMP). All measured radioactive quantities were within safety thresholds established by UNSCEAR, ICRP, WHO, and EPA. In all pediatric medication samples, ²²²Rn concentrations were below legal limits, while ²²⁶Ra and ²³⁸U levels also met international reference standards. The calculated AED and AAIED values remained within permissible exposure limits, indicating negligible radiological danger. However, ELCR values (2.50-6.57 × 10^-³) exceeded minimal international risk thresholds, with the highest value observed in sample S21, suggesting a non-negligible long-term concern. These findings highlight the need for continuous monitoring and stricter quality control, particularly for imported medicines, to ensure long-term safety in this vulnerable population. From a regulatory perspective, the results support incorporating radiological screening into pharmaceutical quality assurance programs by the Iraqi Ministry of Health and drug importation agencies. Overall, while pediatric medications in Erbil appear radiologically safe, ongoing surveillance is warranted to mitigate potential risks from elevated activity concentrations in selected samples.

Radon (²²²Rn) and thoron (²²⁰Rn) with their progeny (RnP and TnP) are naturally occurring gases posing health risks when accumulated indoors. This study presents the first geostatistical mapping of indoor exposure to these radionuclides in the diamond mining regions of Yokadouma and Mobilong, eastern Cameroon. Over 101 days, activity concentrations were measured in 50 dwellings using radon - thoron discriminative detectors (RADUET) and progeny sensors (DRPS/DTPS). Data were log-linearly normalised and spatially interpolated by ordinary kriging in ArcGIS to assess long-term human and environmental impacts in radiologically enriched mining areas. Radon concentrations ranged from 12.3 to 198.7 Bq m^-³, thoron from 9.8 to 389 Bq m^-³, with progeny levels of 0.3-2.7 Bq m^-³ (RnP) and 0.2-2.1 Bq m^-³ (TnP). Estimated annual effective doses varied from 0.3 to 9.7 mSv y^-¹. Active mining sites accounted for over 50 % of RnP and TnP levels due to granite and thorium-rich bedrock. Inhalation doses averaged 5.4 ± 0.8 mSv y^-¹ in active mines, 4.8 ± 0.7 mSv y^-¹ in nearby villages, and 3.6 ± 0.5 mSv y^-¹ in Yokadouma. About 26 % of homes exceeded the ICRP's 6 mSv y^-¹ limit, mainly in poorly ventilated mining zones. Kriging and variogram modelling identified high-risk zones requiring intervention. Spatial variability correlated with building materials and ventilation. The inactive Mobilong site showed minimal influence (< 5 %). Findings emphasise mining's role in enhancing indoor radiological hazards and support targeted monitoring and mitigation policies.

Understanding movements of animals and people in modern or historic contexts is hindered by limited animal tissue proxies to indicate regional origins. On North America's east coast, stable oxygen and hydrogen isoscapes provide broad latitudinal proxies, but more nuanced geographical proxies are lacking. This study examines oxygen, strontium, and sulfur isotopes in deer bone bioapatite and collagen from Virginia, USA, which reflects grazing location, to create the first robust δ³⁴S_collagen distribution in this region, contribute new ⁸⁷Sr/⁸⁶Sr_bone data to a currently small regional dataset, consider δ¹⁸O_bioapatite values on a more nuanced scale, determine which isotope systems best indicate particular regions, and especially consider the efficacy of δ³⁴S_collagen for geographic location. Random forest models show longitudinal trends in δ¹⁸O_bioapatite and ⁸⁷Sr/⁸⁶Sr_bone data; δ³⁴S_collagen values were more variable across Virginia with unique values in specific areas. Model results suggest δ¹⁸O_bioapatite values are most affected by geomorphic and meteorological controls, specifically altitude effects of the Appalachian Mountains, aridity, and mean annual temperature. The ⁸⁷Sr/⁸⁶Sr_bone ratios are controlled largely by underlying bedrock geology, allochthonous dust and sea spray deposition, and surface source mixing. The western coal-bearing formations of the Appalachian Plateau showed relatively low δ³⁴S_collagen values; the eastern Coastal Plains showed relatively high δ³⁴S_collagen resulting from dust and sea spray deposition. Modeled proxies for modern anthropogenic inputs of these elements (e.g. fossil fuels) notably were not strong controlling factors for these isotope systems; therefore, the models produced here are suitable for identification of geographic location using bone isotope values from modern, historic, or paleontological samples. Linear discriminant analysis suggests A multi-isotope approach using δ¹⁸O_bioapatite, ⁸⁷Sr/⁸⁶Sr_bone, and δ³⁴S_collagen data provides a more nuanced geographic prediction than one isotope system alone in this region. The δ³⁴S_collagen values in particular are emerging as a potential new proxy to indicate broad east-west movements of animals and people.

Nuclear medicine has witnessed revolutionary progress, spurred by advances in radiopharmaceuticals, computational modeling, and artificial intelligence. These advances have not only improved cancer diagnosis and treatment but also broadened nuclear medicine's application in the treatment of cardiovascular, neurological, and infectious diseases. The current research presents an in-depth review of radiotracers, encompassing production processes, market trends, and India's strategic initiatives towards improving nuclear medicine infrastructure. Emphasis on four key isotopes, ¹³¹I, ^99mTc, ¹⁸F, and ¹¹C, featuring their changing clinical use, ranging from high-resolution imaging to targeted radiopharmaceuticals treatments. The inclusion of radiopharmaceuticals with organic-based molecules has also improved drug delivery effectiveness by providing better specificity and lower toxicity. In addition, a comprehensive review of the central role of Geant4 in simulating radiation interactions and dose distribution, highlighting its complementarity with computational human phantoms to achieve higher accuracy in radiation dosimetry, has been discussed. Moreover, the emergence of artificial intelligence-based methods in medical imaging and treatment planning has brought new avenues for automation, diagnostic accuracy, and individualized therapy, notwithstanding issues related to interpretability, data bias, and regulatory issues. The review also discusses fundamental limitations of computational modeling and artificial intelligence implementation, suggesting areas of future research. As new technologies evolve continuously to influence nuclear medicine, interdisciplinary advances are set to redefine diagnostics, enhance therapeutic success, and propel the field towards more individualized, streamlined, and accessible healthcare solutions.

After the Gulf Wars in 1991 and 2003, as well as ISIS, Iraq's environment has experienced significant pollution and degradation, earning it a dubious classification as one of the world's most polluted areas, according to the World Pollution Review. This poses serious health risks to the local population, including a significant increase in female infertility. In this study, uranium concentrations were measured in blood samples collected from three groups: a healthy group (n =  20), primary infertile females (n =  29) and secondary infertile females (n =  11). Uranium concentration was determined by irradiating blood samples with a thermal neutron source (Am-Be) (3.024 × 10⁹ n cm^-2). Hormone concentrations in serum blood were measured using a Snibe Maglumi 800 (CLIA); the concentration of uranium in healthy females was at the rate of 0.712 ppb less than 0.810 ppb limit recommended by ICRP/WHO, while they were high for females suffering from primary and secondary infertility, at a rate of 1.149 and 1.148 ppb, respectively. The effect of uranium on female fertility hormones is of biological significance, especially when exposed to toxic or radioactive levels of uranium, this is a negative indicator of the toxic effect of uranium on female hormones, as there is a clear hormonal imbalance in the concentration of FSH, LH, β-hCG, E2 and progesterone, resulting the inability to get pregnant. One of the most common causes in recent years is the problem of polycystic ovary syndrome (PCOS), which is a high ratio in infertile females (primary infertility 16 % and secondary infertility 21 %) as a result of abnormalities in hormonal levels due to the radiological toxicity effect of uranium.

In karst ecosystems like the Gaoping River Basin (Zunyi, Guizhou Province, China), widespread evaporite deposits and exogenous acids inputs drive a shift in water chemistry from carbonate-dominated to sulfate-dominated regimes. Characterizing sulfate (${\mathrm{SO}}_4^{2-}$) sources and spatiotemporal dynamics is critical for managing vulnerable karst water resources. This study uses hydrochemistry, sulfur-oxygen $({\delta }^{34}{S}_{S{O}_4},{\delta }^{18}{O}_{S{O}_4})$, and water (δD, ${\delta }^{18}{O}_{H_{2}O}$) isotopes, combined with the SIAR model, to trace ${\mathrm{SO}}_4^{2-}$ sources across river reaches and hydrological seasons. Results show that sulfate in the Gaoping River originates from both natural and anthropogenic sources: In the upstream, water-rock interactions during groundwater (GW)-surface water (SW) recharge drive gypsum dissolution in carbonate formations, contributing 20.9-21.7 % of ${\mathrm{SO}}_4^{2-}$ in SW and 20.7-30.4 % in GW. In midstream, where agricultural land use dominates, soil-derived sulfate becomes the primary source, accounting for 23.3-25.8 % (SW) and 24.6-28.3 % (GW), correlated with land-use intensity. In downstream, intensive human activities (sewage discharge, fertilizer application) elevate anthropogenic inputs, with sewage contributing approximately 20.1 % to ${\mathrm{SO}}_4^{2-}$ loads in both SW and GW, and fertilizer inputs accounting for 24.0 %. The SIAR model confirms a transition from geogenic (gypsum, soil sulfate) to anthropogenic dominance downstream, with overall water chemistry shifting to a HCO₃·SO₄-Ca type, indicative of carbonate-to-sulfate evolution. These findings underscore the interplay between karst geology, land use, and hydrological processes in shaping sulfate budgets. The study provides a data-driven framework for targeted management: protecting upstream gypsum outcrops, optimizing midstream agricultural practices, and improving downstream wastewater treatment, thereby advancing sustainable karst water resource management in vulnerable ecosystems.

The uranium levels were investigated in 350 drinking water samples from different aquifers (alluvium, quartzite, limestone, slate, phyllite and schist, hornstone breciss, and granite) in northeastern Rajasthan, India. The LED Fluorimeter (model: LF-2a) technique was employed to determine the uranium levels in the drinking water samples. The uranium concentrations range from 0.62 to 128.63, 0.58 to 99.35, 0.79 to 54.40, 0.61 to 41.35, 2.63 to 3.30, 0.57 to 46.24, and 1.01 to 11.98 µg/L, with mean values of 15.95, 9.14, 14.90, 9.70, 2.97, 12.72, and 4.96 µg/L, respectively, for the alluvium, quartzite, limestone, slate, phyllite and schist, hornstone breciss, and granite aquifers. Uranium concentrations across the studied area varied between 0.57 and 128.63 µg/L, with an average of 13.68 µg/L. About 11.14 % of the samples surpassed the World Health Organization's recommended limit (30 µg/L). The radiation dose was calculated by considering the water intake of various age groups, and found infants received the highest calculated dose. On the radiological aspect, two groundwater samples from an alluvium aquifer exceeded the prescribed level (1.67 × 10^-4) recommended by the Atomic Energy Regulatory Board of India. The average daily dose of uranium from drinking water ranged from 0.02 to 3.68 µg/kg/day. Approximately 8.3 % of the samples from different aquifers surpassed hazard quotient values of unity and indicated chemical toxicity risks. Uranium levels showed no correlation with physicochemical parameters in all the aquifers.