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1.
Biomed Environ Sci ; 37(4): 406-417, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38727163

RESUMO

Objective: This study aimed to efficiently reduce the release of radon from water bodies to protect the environment. Methods: Based on the sizes of the experimental setup and modular float, computational fluid dynamics (CFD) was used to assess the impact of the area coverage rate, immersion depth, diffusion coefficient, and radon transfer velocity at the gas-liquid interface on radon migration and exhalation of radon-containing water. Based on the numerical simulation results, an estimation model for the radon retardation rate was constructed. The effectiveness of the CFD simulation was evaluated by comparing the experimental and simulated variation values of the radon retardation rate with the coverage area rates. Results: The effect of radon transfer velocity on radon retardation in water bodies was minor and insignificant according to the appropriate value; therefore, an estimation model of the radon retardation rate of the coverage of a radon-containing water body was constructed using the synergistic impacts of three factors: area coverage rate, immersion depth, and diffusion coefficient. The deviation between the experimental and simulated results was < 4.3%. Conclusion: Based on the numerical simulation conditions, an estimation model of the radon retardation rate of covering floats in water bodies under the synergistic effect of multiple factors was obtained, which provides a reference for designing covering floats for radon retardation in radon-containing water.


Assuntos
Hidrodinâmica , Radônio , Radônio/análise , Simulação por Computador , Poluentes Radioativos da Água/análise
2.
J Environ Radioact ; 276: 107446, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38733660

RESUMO

Radon presents significant health risks due to its short-lived progeny. The evaluation of the equivalent lung dose coefficient is crucial for assessing the potential health effects of radon exposure. This review focuses on the uncertainty analysis of the parameters associated with the calculation of the equivalent lung dose coefficient attributed to radon inhalation in mines. This analysis is complex due to various factors, such as geological conditions, ventilation rates, and occupational practices. The literature review systematically examines the sources of radon and its health effects among underground miners. It also discusses the human respiratory tract model used to calculate the equivalent lung dose coefficient and the associated parameters leading to uncertainties in the calculated lung dose. Additionally, the review covers the different methodologies employed for uncertainty quantification and their implications on dose assessment. The text discusses challenges and limitations in current research practices and provides recommendations for future studies. Accurate risk assessment and effective safety measures in mining environments require understanding and mitigating parameter uncertainties.


Assuntos
Poluentes Radioativos do Ar , Pulmão , Mineração , Exposição Ocupacional , Radônio , Radônio/análise , Humanos , Exposição Ocupacional/análise , Exposição Ocupacional/estatística & dados numéricos , Pulmão/efeitos da radiação , Incerteza , Poluentes Radioativos do Ar/análise , Medição de Risco/métodos , Doses de Radiação , Monitoramento de Radiação/métodos
3.
J Radiol Prot ; 44(2)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38749401

RESUMO

Kansas State University (KSU) Engineering Extension conducted an abridged evaluation of eight consumer grade digital radon monitors. Using the KSU secondary radon chamber, these devices were exposed to three different radon concentrations for 7 d in average household temperature and relative humidity conditions. The three different radon concentration ranges used were: 12.8 pCi L-1to 15.5 pCi L-1(473.6 Bq m-3-573.5 Bq m-3), 27.7 pCi L-1to 29.4 pCi L-1(1024.9-10 857.8 Bq m-3), and ambient room level average radon concentration of 0.6 pCi L-1(22.2 Bq m-3). The American National Standards Institute/American Academy of Radon Scientists and Technologists Performance Specifications for Instrumentation Systems Designed to Measure Radon Gas in Air (ANSI/AARST MS-PC) (ANSI/AARST MS-PC 2022Performance Specifications for Instrumentation Systems Designed to Measure Radon Gas in Air(AARST Radon Standards)) minimum performance metrics were used to evaluate the accuracy and precision of each model type for each radon concentration tested. The eight different device models performed within the 0 ± 25% requirement for the individual percent error (IPE) for radon concentrations between 27.7 pCi L-1and 29.4 pCi L-1(1024.9-10 857.8 Bq m-3). For radon concentrations between 12.8 pCi L-1and 15.5 pCi L-1(444-592 Bq m-3) seven of the eight monitors fell within the IPE requirement and for ambient room radon concentrations six of the eight monitors fell within the IPE requirement for the ANSI/AARST MS-PC minimum performance requirement (ANSI/AARST MS-PC 2022Performance Specifications for Instrumentation Systems Designed to Measure Radon Gas in Air(AARST Radon Standards)) ranges. All eight device models fell within the ± 15% ANSI/AARST MS-PC minimum performance requirement (ANSI/AARST MS-PC 2022Performance Specifications for Instrumentation Systems Designed to Measure Radon Gas in Air(AARST Radon Standards)) coefficient of variation (CV) range for radon concentrations between 12.8 pCi L-1and 15.5 pCi L-1(444-592 Bq m-3) and for radon concentrations between 27.7 pCi L-1and 29.4 pCi L-1(1024.9-10 857.8 Bq m-3). In the future, evaluating the performance of these models over time to observe their long term accuracy and precision is anticipated.


Assuntos
Poluentes Radioativos do Ar , Poluição do Ar em Ambientes Fechados , Monitoramento de Radiação , Radônio , Radônio/análise , Monitoramento de Radiação/instrumentação , Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Desenho de Equipamento
4.
Neuroimage ; 292: 120606, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38604538

RESUMO

Radon is a naturally occurring gas that contributes significantly to radiation in the environment and is the second leading cause of lung cancer globally. Previous studies have shown that other environmental toxins have deleterious effects on brain development, though radon has not been studied as thoroughly in this context. This study examined the impact of home radon exposure on the neural oscillatory activity serving attention reorientation in youths. Fifty-six participants (ages 6-14 years) completed a classic Posner cuing task during magnetoencephalography (MEG), and home radon levels were measured for each participant. Time-frequency spectrograms indicated stronger theta (3-7 Hz, 300-800 ms), alpha (9-13 Hz, 400-900 ms), and beta responses (14-24 Hz, 400-900 ms) during the task relative to baseline. Source reconstruction of each significant oscillatory response was performed, and validity maps were computed by subtracting the task conditions (invalidly cued - validly cued). These validity maps were examined for associations with radon exposure, age, and their interaction in a linear regression design. Children with greater radon exposure showed aberrant oscillatory activity across distributed regions critical for attentional processing and attention reorientation (e.g., dorsolateral prefrontal cortex, and anterior cingulate cortex). Generally, youths with greater radon exposure exhibited a reverse neural validity effect in almost all regions and showed greater overall power relative to peers with lesser radon exposure. We also detected an interactive effect between radon exposure and age where youths with greater radon exposure exhibited divergent developmental trajectories in neural substrates implicated in attentional processing (e.g., bilateral prefrontal cortices, superior temporal gyri, and inferior parietal lobules). These data suggest aberrant, but potentially compensatory neural processing as a function of increasing home radon exposure in areas critical for attention and higher order cognition.


Assuntos
Atenção , Magnetoencefalografia , Radônio , Humanos , Adolescente , Criança , Masculino , Feminino , Radônio/toxicidade , Radônio/efeitos adversos , Atenção/efeitos da radiação , Atenção/fisiologia , Exposição Ambiental/efeitos adversos , Encéfalo/efeitos da radiação , Ondas Encefálicas/efeitos da radiação , Ondas Encefálicas/fisiologia , Ondas Encefálicas/efeitos dos fármacos , Orientação/fisiologia
5.
J Radiol Prot ; 44(2)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38632901

RESUMO

The high radon concentrations measured in the indoor air of groundwater facilities and the prevalence of the problem have been known for several years. Unlike in other workplaces, in groundwater plants, radon is released into the air from the water treatment processes. During the measurements of this study, the average radon concentrations varied from 500 to 8800 Bq m-3. In addition, the indoor air of the treatment plants is filtered and there are no significant internal aerosol sources. However, only a few published studies on groundwater plants have investigated the properties of the radon progeny aerosol, such as the equilibrium factor (F) or the size distribution of the aerosol, which are important for assessing the dose received by workers. Moreover, the International Commission on Radiological Protection has not provided generic aerosol parameter values for dose assessment in groundwater treatment facilities. In this study, radon and radon progeny measurements were carried out at three groundwater plants. The results indicate surprisingly high unattached fractions (fp= 0.27-0.58), suggesting a low aerosol concentration in indoor air. The correspondingFvalues were 0.09-0.42, well below those measured in previous studies. Based on a comparison of the effective dose rate calculations, either the determination of thefpor, with certain limitations, the measurement of radon is recommended. Dose rate calculation based on the potential alpha energy concentration alone proved unreliable.


Assuntos
Poluentes Radioativos do Ar , Poluição do Ar em Ambientes Fechados , Água Subterrânea , Monitoramento de Radiação , Radônio , Humanos , Produtos de Decaimento de Radônio/análise , Poluentes Radioativos do Ar/análise , Radônio/análise , Aerossóis , Monitoramento de Radiação/métodos , Poluição do Ar em Ambientes Fechados/análise
6.
J Contam Hydrol ; 263: 104342, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38643702

RESUMO

A recent diesel spill (dated January 2019 ± 1 month) in a refilling station is investigated by the Radon deficit technique. The primary focus was on quantifying the LNAPL pore saturation as a function of duration of ageing, and on proposing a predictive model for on-site natural attenuation. A biennial monitoring of the local fluctuating shallow aquifer has involved the saturated zone nine times, and the vadose zone only once. Rn background generally measured in external and upstream wells is elaborated further due to the site characteristics, using drilling logs and phreatic oscillations. Notably, this study marks the first application of the Rn deficit method to produce a detailed Rn background mapping throughout the soil depth. Simultaneously, tests are performed on LNAPL surnatant samples to study diesel ageing. In particular, they are focused on temporal variations of LNAPL viscosity (from an initial 3.90 cP to 8.99 cP, measured at 25 °C, after 34 months), and Rn partition coefficient between the pollutant and water (from 47.7 to 80.2, measured at 25 °C, after 14 months). Rn diffusion is also measured in different fluids (0.092 cm2 s-1, 1.14 × 10-5 cm2 s-1, and 2.53 × 10-6 cm2 s-1 at 25 °C for air, water and LNAPL, respectively) directly. All parameters and equations utilized during this study are introduced, discussing their influence on Radon deficit technique from a theoretical point of view. Experimental findings are used to mitigate the effect of LNAPL ageing and of phreatic oscillations on determination of LNAPL saturation index (S.I.LNAPL). Finally, S.I.LNAPL dataset is discussed and elaborated to show the pollutant attenuation across subsurface over time, induced by natural processes primarily. The proposed predictive model for on-site natural attenuation suggests a half-removal time of one year and six months. The significance of such models lies in their capability to assess site-specific reactions to pollutants, thereby enhancing the effectiveness of remediation efforts over time. These experimental findings may offer a novel approach to application of Rn deficit technique and to environmental remediation of persistent organic compounds.


Assuntos
Água Subterrânea , Radônio , Água Subterrânea/química , Radônio/análise , Poluentes Radioativos da Água/análise , Vazamento de Resíduos Químicos , Gasolina , Monitoramento Ambiental/métodos
7.
J Environ Radioact ; 276: 107440, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38669858

RESUMO

The radiation dose of workers in underground uranium mines mainly comes from radon and radon progeny. To ensure a healthy and safe work environment, it is necessary and urgent to optimize the design of ventilation systems. As such, based on the simplified radon diffusion-advection migration model of the rocks, this paper proposes 1) two methods for determining the radon exhalation rate modified by pressure drop, 2) three methods for calculating radon activity concentration of single-branch, and 3) the novel adjustment algorithm and solving procedures for calculating and adjusting the radon activity concentration in ventilation networks by modifying the radon exhalation rate, demonstrated on a specific ventilation network in a simulated underground uranium mine with calculation and analysis via MATLAB. The results show that 1) the radon exhalation rate of different branches can be modified by their pressure drop, and 2) the proposed method can be used to reveal the influences of different ventilation methods and fan pressures on the radon activity concentration in the ventilation network and the radon release rate to the atmosphere.


Assuntos
Poluentes Radioativos do Ar , Mineração , Modelos Teóricos , Monitoramento de Radiação , Radônio , Urânio , Ventilação , Radônio/análise , Urânio/análise , Poluentes Radioativos do Ar/análise , Monitoramento de Radiação/métodos , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Exposição Ocupacional/análise
8.
Radiat Environ Biophys ; 63(2): 271-281, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38668871

RESUMO

The most significant source of human exposure to ionizing radiation is the radioactive gas radon (basically 222Rn) and its daughter decay products, creating more than half of the effective dose from all natural sources. Radon enters buildings mainly from dense rocks, which are below building foundations at depths of 1 m and more. In this paper long-term measurements of radon flux density are analyzed, with radon exhalation from the surface of the most common rocks-loams, sandy loams, clays, clay shales, several types of sandy-gravel-pebble deposits, clay and rocky limestone. The influence of geophysical properties of rocks on radon flux density due to exhalation from surfaces of those rocks was studied. Based on the results obtained, a method of local assessment of the hazard from radon and its progeny in buildings is proposed, which is based on the geophysical properties of rocks below the foundations of those buildings.


Assuntos
Radônio , Radônio/análise , Monitoramento de Radiação/métodos , Fenômenos Geológicos
9.
Neurology ; 102(4): e209143, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38546022

RESUMO

BACKGROUND AND OBJECTIVES: Little is known about the role of radon in the epidemiology of stroke among women. We therefore examined the association between home radon exposure and risk of stroke among middle-aged and older women in the United States. METHODS: We conducted a prospective cohort study of postmenopausal women aged 50-79 years at baseline (1993-1998) in the Women's Health Initiative. We measured exposures as 2-day, indoor, lowest living-level average radon concentrations in picocuries per liter (pCi/L) as estimated in 1993 by the US Geological Survey and reviewed by the Association of American State Geologists under the Indoor Radon Abatement Act. We used Cox proportional hazards models to estimate risk of incident, neurologist-adjudicated stroke during follow-up through 2020 as a hazard ratio and 95% CI, adjusting for study design and participant demographic, social, behavioral, and clinical characteristics. RESULTS: Among 158,910 women without stroke at baseline (mean age 63.2 years; 83% white), 6,979 incident strokes were identified over follow-up (mean 13.4 years). Incidence rates were 333, 343, and 349 strokes per 100,000 woman-years at radon concentrations of <2, 2-4, and >4 pCi/L, respectively. Compared with women living at concentrations <2 pCi/L, those at 2-4 and >4 pCi/L had higher covariate-adjusted risks of incident stroke: hazard ratio (95% CI) 1.06 (0.99-1.13) and 1.14 (1.05-1.22). Using nonlinear spline functions to model radon, stroke risk was significantly elevated at concentrations ranging from 2 to 4 pCi/L (p = 0.0004), that is, below the United States Environmental Protection Agency Radon Action Level for mitigation (4 pCi/L). Associations were slightly stronger for ischemic (especially cardioembolic, small vessel occlusive, and large artery atherosclerotic) than hemorrhagic stroke, but otherwise robust in sensitivity analyses. DISCUSSION: Radon exposure is associated with moderately increased stroke risk among middle-aged and older women in the United States, suggesting that promulgation of a lower Radon Action Level may help reduce the domestic impact of cerebrovascular disease on public health.


Assuntos
Acidente Vascular Cerebral Hemorrágico , Radônio , Acidente Vascular Cerebral , Pessoa de Meia-Idade , Humanos , Feminino , Estados Unidos/epidemiologia , Idoso , Estudos Prospectivos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Radônio/efeitos adversos , Radônio/análise , Saúde da Mulher , Fatores de Risco , Incidência
10.
Health Phys ; 126(5): 315-321, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38526250

RESUMO

ABSTRACT: In Canada, leukemia is diagnosed at a rate of 15 cases per 100,000 persons and accounts for about 3% of all new primary cancers. In this study, geographical correlation between residential radon exposure and leukemia incidence was investigated at a provincial level with more accurate long-term radon measurement data in 21,330 homes and 10-y (2000-2009) age standardized incidence rates per 100,000 population for various subtypes of leukemia. The analyses showed that the incidence rate of non-Hodgkin lymphoma is statistically significantly correlated with average indoor radon (222Rn) concentration for Canadian females (p = 0.01210) but not for males. At a provincial level, the association between average indoor radon level and chronic lymphocytic leukemia incidence rate is statistically significant (p = 0.0167), and the correlation is somewhat stronger for females (p = 0.0043). No correlation was found between indoor radon exposure and any other subtypes of leukemia evaluated in this study.


Assuntos
Leucemia , Radônio , Feminino , Masculino , Humanos , Incidência , Radônio/efeitos adversos , Canadá/epidemiologia
11.
J Radiol Prot ; 44(2)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38537265

RESUMO

Radon, a naturally occurring radioactive gas, poses a significant public health risk. This study aimed to assess indoor radon exposure in Saudi Arabia using the health belief model (HBM) as a framework for understanding and influencing public behaviour regarding the prevention on indoor radon exposure.A cross-sectional analytical study was conducted involving 803 participants from diverse backgrounds recruited through convenience sampling. The online questionnaire assessed sociodemographics, risk factors, and HBM constructs (perceived susceptibility, barriers, benefits, seriousness, and self-efficacy). Statistical analysis was conducted using SPSS.Most participants showed neutral perceptions towards susceptibility, severity (82.7% each), benefits (85.2%), and barriers (59.7%) to preventive practices. Only 31.6% had high self-efficacy, with 16.4% practicing good prevention and 44.3% fair. Preventive practices correlated positively with perceived severity, benefits, and self-efficacy, but negatively with risk score and perceived barriers.The study highlights the need for improved radon prevention practices in Saudi Arabia, focusing on educational campaigns, self-efficacy enhancement, policy support for renters, and better risk communication. These measures are crucial for mitigating radon exposure risks across the population.


Assuntos
Radônio , Humanos , Estudos Transversais , Arábia Saudita , Radônio/análise , Inquéritos e Questionários , Fatores de Risco
12.
Sci Rep ; 14(1): 6042, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38472226

RESUMO

Geospatial methods, such as GIS and remote sensing, map radon levels, pinpoint high-risk areas and connect geological traits to radon presence. These findings direct health planning, focusing tests, mitigation, and policies where radon levels are high. Overall, geospatial analyses offer vital insights, shaping interventions and policies to reduce health risks from radon exposure. There is a formidable threat to human well-being posed by the naturally occurring carcinogenic radon (222Rn) gas due to high solubility in water. Under the current scenario, it is crucial to assess the extent of 222Rn pollution in our drinking water sources across various regions and thoroughly investigate the potential health hazards it poses. In this regard, the present study was conducted to investigate the concentration of 222Rn in groundwater samples collected from handpumps and wells and to estimate health risks associated with the consumption of 222Rn-contaminated water. For this purpose, groundwater samples (n = 30) were collected from handpumps, and wells located in the Mulazai area, District Peshawar. The RAD7 radon detector was used as per international standards to assess the concentration of 222Rn in the collected water samples. The results unveiled that the levels of 222Rn in the collected samples exceeded the acceptable thresholds set by the US Environmental Protection Agency (US-EPA) of 11.1 Bq L-1. Nevertheless, it was determined that the average annual dose was below the recommended limit of 0.1 mSv per year, as advised by both the European Union Council and the World Health Organization. In order to avoid the harmful effects of such excessive 222Rn concentrations on human health, proper ventilation and storage of water in storage reservoirs for a long time before use is recommended to lower the 222Rn concentration.


Assuntos
Água Potável , Água Subterrânea , Monitoramento de Radiação , Radônio , Poluentes Radioativos da Água , Humanos , Água Potável/análise , Monitoramento de Radiação/métodos , Radônio/análise , Paquistão , Poluentes Radioativos da Água/análise , Água Subterrânea/análise , Poluição da Água/análise
13.
Appl Radiat Isot ; 207: 111265, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38432033

RESUMO

This study involved the assessment of 222Rn concentrations in liquid samples (namely serum and urine) obtained from individuals who were smokers and non-smokers across five distinct age groups in the Najaf Governorate of Iraq. The measurements were conducted using a portable digital Air Things device commonly employed for detecting radon gas in residential environments. This device was placed in a container that is placed in liquid samples, which makes it work to capture the existing radon. The mean value of radon concentrations in serum and urine samples for smokers was 5.64 ± 2.80 Bq/m3 and 3.56 ± 2.31 Bq/m3, respectively. While, the mean value of radon concentrations in serum and urine samples for non-smokers was 2.32 ± 0.67 Bq/m3 and 1.61 ± 1.00 Bq/m3, respectively. By comparing the radon concentrations for serum and urine samples with age and smoking groups, the value of P-Value (p < 0.01) was increased significantly statistically. Also, it is found that a positive and good correlation for radon concentrations between serum and urine. Although the levels of radon were found to be under the globally accepted thresholds, the results of 222Rn in all samples of serum and urine in smokers were higher than in non-smokers. Thus, it may be concluded that cigarette smoking is used as a biomarker of the presence of radon gas.


Assuntos
Poluentes Radioativos do Ar , Poluição do Ar em Ambientes Fechados , Monitoramento de Radiação , Radônio , Humanos , Radônio/análise , Poluição do Ar em Ambientes Fechados/análise , Habitação , Poluentes Radioativos do Ar/análise , Meio Ambiente , Monitoramento de Radiação/métodos
14.
J Environ Radioact ; 274: 107409, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428363

RESUMO

The study presented the relationship between sudden Natural Gamma Radiation (NGR) increases related to enhanced atmospheric electric fields. We pinpoint Thunderstorm Ground Enhancements (TGEs) as the primary source of abrupt and significant NGR spikes. These TGEs, which are transient, several-minute-long increases in elementary particle fluxes, originate from natural electron accelerators within thunderclouds. The more prolonged, yet less pronounced, increases in NGR, persisting for several hours, are attributed to the gamma radiation from radon progeny and enhanced positron fluxes. This radon, emanating from terrestrial materials, is carried aloft by the Near-Surface Electric Field (NSEF). To measure NGR at Aragats Mountain, we use an ORTEC detector and custom-built large NaI (Tl) spectrometers, employing lead filters to discriminate between cosmic ray fluxes and radon progeny radiation. Our analysis differentiates between radiation enhancements during positive and negative NSEF episodes. The resultant data provide a comprehensive measurement of the intensities of principal isotopes and positron flux during thunderstorms compared to fair weather conditions.


Assuntos
Monitoramento de Radiação , Radônio , Produtos de Decaimento de Radônio/análise , Raios gama , Radônio/análise , Atmosfera
15.
Environ Sci Pollut Res Int ; 31(17): 24951-24960, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460038

RESUMO

Solid process fine waste or tailings of a uranium mill is a potential source of release of radiologically significant gaseous radon (222Rn). A number of variables such as radium (226Ra) content, porosity, moisture content, and tailings density can affect the extent of emanation from the tailings. Further, if a cover material is used for remediation purposes, additional challenges due to changes in the matrix characteristics in predicting the radon flux can be anticipated. The uranium mill tailings impoundment systems at Jaduguda have been in use for the long-term storage of fine process waste (tailings). A pilot-scale remediation exercise of one of the tailings ponds has been undertaken with 30 cm soil as a cover material. For the prediction of the radon flux, a numerical model has been developed to account for the radon exhalation process at the remediated site. The model can effectively be used to accommodate both the continuous and discrete variable inputs. Depth profiling and physicochemical characterization for the remediated site have been done for the required input variables of the proposed numerical model. The predicted flux worked out is well below the reference level of 0.74 Bq m-2 s-1 IAEA (2004).


Assuntos
Rádio (Elemento) , Radônio , Poluentes Radioativos do Solo , Urânio , Radônio/análise , Poluentes Radioativos do Solo/análise , Índia , Resíduos Sólidos
16.
Radiat Prot Dosimetry ; 200(6): 617-622, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516732

RESUMO

Passive diffusion radon monitoring devices were exposed to a range of radon concentrations and their variations. The experimental results, backed up by the statistical analysis, showed that the radon concentration had virtually no effect on the final integrated exposure results, with the exception for the very low concentration. Therefore, it was proven that such devices are truly integrated exposure devices.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Radônio , Radônio/análise , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/métodos , Poluentes Radioativos do Ar/análise , Humanos , Desenho de Equipamento , Poluição do Ar em Ambientes Fechados/análise
17.
Radiat Prot Dosimetry ; 200(6): 544-553, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38446413

RESUMO

Our work investigated the radioprotection implications associated with the possession of a collection of uraniferous minerals. Considering different scenarios, we developed (and applied to an actual collection) specific formulas for radiation doses evaluation. We discussed the shielding necessary to reduce the gamma irradiation down to the required values. A mathematical model was developed to estimate the minimum air flow rate to reduce the radon air concentration below the reference values. The radiation risks associated to the handling of single specimens was also addressed, including hand skin irradiation and shielding capabilities of surgical lead gloves. Finally, we discussed the radiation risks associated to the exhibition of a single specimen. The results, compared to the safety standards of the EU Directive 13/59, show that the exhibition of uraniferous samples with activity of a few MBq do not need specific radioprotection requirements nor for the involved personnel nor for visitors.


Assuntos
Exposição Ocupacional , Monitoramento de Radiação , Proteção Radiológica , Proteção Radiológica/normas , Proteção Radiológica/métodos , Humanos , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Monitoramento de Radiação/métodos , Doses de Radiação , Minerais/análise , Raios gama , Radônio/análise , Poluentes Radioativos do Ar/análise , Urânio/análise , Modelos Teóricos
18.
J Environ Manage ; 356: 120675, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38493642

RESUMO

Radon (222Rn) is a radioactive gas that occurs naturally in the soil and is harmful to the environment and health. However, the measuring the amount of radon flowing is challenging. This study reveals the mechanism responsible for radon transportation and concentration variation, the main driving forces acting, and the key factors operating in the vadose zone. In this study, two separate holes were used to monitor the amount of earth-air and radon flowing in and out of the soil in the extremely arid region in China where the Mogao Grottoes are located. Using a closed-system model, the quantity, characteristics, and regularity of the flow of earth-air and radon were thus determined on daily and yearly timescales. The same patterns of variation in earth-air flow and radon concentration were found at the two sites, both depending on the variation in the atmospheric pressure (AP). When the AP decreases, earth-air flows out from the soil with a high radon concentration. Conversely, when the AP increases, earth-air enters into the soil with a low radon concentration. Thus, radon is continuously emitted from the soil. The concentration of radon in the earth-air is proportional to the rate of flow of earth-air and therefore increases as the AP decreases. The radon emission also varies with the seasonal variation in temperature and AP, which is high in summer and low in winter. On a daily timescale, the radon varies in a bimodal manner. Therefore, the net amount of radon emitted from the soil is positively correlated with the amplitude of the AP fluctuation, temperature, soil porosity, and thickness of the vadose zone. The atmospheric pumping is the main driving force responsible for the radon emission. However, the surface closure, landform, cracks, faults, grain size, pore structure, soil adsorption, basal uranium/radium, salts, wind, lunar cycle, latitude and altitude have important effects on the number of radon emission. As such, it provides a scientific basis for the effective utilization of radon and prevention of its emission from soil.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Solo , Radônio/análise , Estações do Ano , Temperatura , Vento , Solo , Poluentes Radioativos do Solo/análise , Poluentes Radioativos do Ar/análise
19.
J Vet Intern Med ; 38(3): 1659-1665, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38437620

RESUMO

BACKGROUND: Multicentric lymphoma (ML) in dogs resembles non-Hodgkin lymphoma (NHL) in humans. Human NHL is associated with multiple environmental exposures, including to radon and volatile organic compounds (VOCs). HYPOTHESIS/OBJECTIVES: The objective of this study was to determine whether ML in dogs was associated with environmental radon or proximity to horizontal oil and drilling (fracking), a source of VOC pollution. METHODS: We identified dogs from the Golden Retriever Lifetime Study that developed ML (n = 52) along with matched controls (n = 104). Dog home addresses were categorized by Environmental Protection Agency radon zone and average residential radon by county, as well as by distance from fracking and associated wastewater wells. RESULTS: We found no significant differences in county level radon measurements. Individual household radon measurements were not available. There was no difference in residential proximity to active fracking wells between dogs with ML and unaffected dogs. While dogs with ML lived closer to wastewater wells (123 vs 206 km; P = .01), there was no difference in the percentage of cases vs controls that lived in close proximity (20 km) to a fracking well (11.5% for cases, 6.7% for controls; OR 1.81, 95% CI 0.55 to 5.22; P = .36), or a wastewater well (6.7% for cases, 4.4% for controls; P > .99). CONCLUSIONS AND CLINICAL IMPORTANCE: These data suggest that more proximate sources of chemical exposures need to be assessed in dogs with ML, including measurements of individual household radon and household VOC concentrations.


Assuntos
Doenças do Cão , Exposição Ambiental , Radônio , Animais , Cães , Radônio/análise , Doenças do Cão/etiologia , Masculino , Feminino , Exposição Ambiental/efeitos adversos , Estudos de Casos e Controles , Linfoma/veterinária , Compostos Orgânicos Voláteis/análise , Fraturamento Hidráulico
20.
Front Public Health ; 12: 1328955, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525346

RESUMO

Gold mine tailings, a legacy of the mining industry, harbors significant amount of radon gas, a classified human carcinogen. Radon exposure, especially near tailings, is a significant public health threat, potentially leading to increased risk of lung cancer, leukemia, and chronic obstructive pulmonary disease (COPD). These health problems are often associated with lower survival rates and significant financial burdens. This ongoing research aim to evaluating the relationship between indoor radon exposure and lung cancer, leukemia, and COPD risks among residents proximal to gold mine tailings in Gauteng Province, South Africa. This cross-sectional preliminary study focus on two distinct groups: Riverlea (exposed group, <2 km to Gold mine tailings) and Orlando East (unexposed group, >2 km to Gold mine tailings). Indoor radon levels is measured using AlphaE monitors, while health risks (lung cancer, leukemia, and COPD) linked to exposure are evaluated through interview-administered questionnaire and secondary data from Gauteng Health Department. Of the 476 residents randomly selected for this study, 300 have already participated, with balanced representation from both the exposed and unexposed groups. The study will compare indoor radon levels and health outcomes between the two groups. This study's results could aid in creating targeted interventions and policies to mitigate indoor radon exposure risks and safeguard vulnerable communities from this significant public health hazard.


Assuntos
Leucemia , Neoplasias Pulmonares , Doença Pulmonar Obstrutiva Crônica , Radônio , Humanos , Ouro , África do Sul/epidemiologia , Estudos Transversais , Radônio/efeitos adversos , Radônio/análise , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia
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