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1.
Microsc Res Tech ; 87(7): 1507-1520, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38419356

RESUMO

In this article, we present a new method called point spread function (PSF)-Radon transform algorithm. This algorithm consists on recovering the instrument PSF from the Radon transform (in the line direction axis) of the line spread function (i.e., the image of a line). We present the method and tested with synthetic images, and real images from macro lens camera and microscopy. A stand-alone program along with a tutorial is available, for any interested user, in Martinez (PSF-Radon transform algorithm, standalone program). RESEARCH HIGHLIGHTS: Determining the instrument PSF is a key issue. Precise PSF determinations are mandatory if image improvement is performed numerically by deconvolution. Much less exposure time to achieve the same performance than a measurement of the PSF from a very small bead. Does not require having to adjust the PSF by an analytical function to overcome the noise uncertainties.

2.
Clin Transl Oncol ; 26(2): 352-362, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37490262

RESUMO

The incidence and mortality of lung cancer in women are rising, with both increasing by 124% between 2003 and 2019. The main risk factor for lung cancer is tobacco use, but indoor radon gas exposure is one of the leading causes in nonsmokers. The most recent evidence demonstrates that multiple factors can make women more susceptible to harm from these risk factors or carcinogens. For this consensus statement, the Association for Lung Cancer Research in Women (ICAPEM) invited a group of lung cancer experts to perform a detailed gender-based analysis of lung cancer. Clinically, female patients have different lung cancer profiles, and most actionable driver alterations are more prevalent in women, particularly in never-smokers. Additionally, the impact of certain therapies seems to be different. In the future, it will be necessary to carry out specific studies to improve the understanding of the role of certain biomarkers and gender in the prognosis and evolution of lung cancer.


Assuntos
Poluição do Ar em Ambientes Fechados , Neoplasias Pulmonares , Radônio , Masculino , Humanos , Feminino , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/terapia , Radônio/efeitos adversos , Poluição do Ar em Ambientes Fechados/efeitos adversos , Fatores de Risco , Incidência
3.
Appl Radiat Isot ; 205: 111158, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38159450

RESUMO

The risk of lung cancer or pneumoconiosis mortality, increases with radioactive radon gas exposures. This article report health risk for underground workers exposed to radioactive gas and radon daughters carried by airborne dust at the coal mining in the Central Mountainous Region of Colombia. A set of 33 measurement points located in that mine galleries were selected to monitor radon gas concentration activity, by passive LR-115 detectors, during two months. Resulting values provided radon concentrations, absorbed dose, environmental equivalent dose and the effective dose; miners increased risk of contracting lung cancer is included. It is concluded that the mine ventilation system satisfies the conditions required by the current radiological protection of the miners. Our study point out that Colombia can effectively address the potential risks associated with radon exposure and ensure a safer living environment for its citizens.


Assuntos
Neoplasias Pulmonares , Exposição Ocupacional , Radônio , Humanos , Radônio/efeitos adversos , Radônio/análise , Neoplasias Pulmonares/etiologia , Colômbia , Produtos de Decaimento de Radônio/análise , Carvão Mineral/efeitos adversos , Exposição Ocupacional/efeitos adversos
4.
Appl Radiat Isot ; 201: 111020, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37729724

RESUMO

The term "commercial ornamental stones" comprises different natural stones with different mineralogical components and the distribution and amount of natural radionuclides depended on the mineralogy. Few studies on natural radioactivity in ornamental stones carried out in Rio de Janeiro (Brazil) and the present work were carried out in order to analyze the distribution of activity concentration in these materials. The activity concentration of 238U, 235U, 226Ra, 232Th and 40K in Ornamental Stones measured using γ-ray spectrometry to estimate the radiation hazard as well as establishing a database for radioactivity levels. Samples were collected in stores in Rio de Janeiro, carefully transported, weighed, packed with PVC film and left to rest for at least 45 days to reach secular equilibrium. Samples analyzed by gamma spectrometry using a hyper pure germanium detector (HPGE). Detection efficiency for each sample was obtained using LabSOCS software. The activity concentrations for samples were within the ranges (0.83 ± 0.15 to 39.96 ± 1.19, 8.04 ± 2.54 to 111.36 ± 13.33, 0.43 ± 0.03 to 264.58 ± 0.98, BDL to 8.17± 0.65 and 1.30 ± 0.57 to 1567.01 ± 65.08) Bq⋅kg-1 for 238U, 226Ra, 232Th, 235U and 40K, respectively. The world average for building materials is 50 Bq⋅kg-1 for 238U, 50 Bq.kg-1 for 232Th and 500 Bq⋅kg-1 for 40K. In the present work, the average for granite was 19.43 ± 0.39 Bq⋅kg-1 for 238U, 56.70 ± 1.13 Bq⋅kg-1 for 232Th and 1113.28 ± 20.27 Bq⋅kg-1 for 40K, thus the values for 232Th and 238U are above the world average. Analyzing for the granite that showed the highest concentrations of activity the average values of Transport Rate was 3.12 ± 0.04 Bq⋅m-2⋅s-1, Emanation Rate was 0.16 ± 0.00 Bq⋅kg-1⋅s-1, Exhalation Flow was 530.26 ± 6.05 Bq⋅m-3, Effective Equivalent Dose Due to Radon Exposure was 0.78 ± 0.01 WLM⋅year-1 and Annual Effective Dose Due to Radon and Thoron was 7.02 ± 0.10 mSv⋅year-1. Annual Effective Dose Due to Radon and Thoron it is above the annual limit for public individuals which is 1 mSv⋅year-1 and below the occupationally exposed individual, which is 20 mSv⋅year-1 in an average of 5 years, it does not exceed the maximum level recommended by ICRP-60.

5.
Clin Transl Oncol ; 25(12): 3357-3368, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37610496

RESUMO

We aim to provide an overview of the research available on indoor radon and lung cancer, with a special focus on Spanish investigations. Early studies on underground miners established the link between radon and lung cancer, which was later confirmed for the general population by residential case-control studies. Spain contributed with extensive evidence, including 5 multicentric, hospital-based, case-control studies in the last 30 years, exploring diverse aspects, such as radon's effect on never-smokers, molecular pathways linking radon exposure to lung cancer risk, survival rates, mortality burden, and occupational exposure. There is a well-established causal association between radon with lung cancer. Despite pioneering research performed in our country by the Galician Radon Laboratory, particularly on driver genes, the evidence on the potential molecular pathways which makes radon a carcinogen is sparse. Also, relevant questions on the potential association of radon exposure with the induction of other diseases are still pending.


Assuntos
Poluição do Ar em Ambientes Fechados , Neoplasias Pulmonares , Neoplasias Induzidas por Radiação , Radônio , Humanos , Radônio/efeitos adversos , Radônio/análise , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Poluição do Ar em Ambientes Fechados/efeitos adversos , Neoplasias Induzidas por Radiação/etiologia , Risco
6.
Environ Sci Pollut Res Int ; 30(38): 89140-89152, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37442937

RESUMO

The state of Rio Grande do Norte, located in the Northeast region of Brazil, has areas of granites and pegmatites with minerals that have varying concentrations of uranium. Consequently, high concentrations of radon gas, a carcinogenic substance for humans, can occur. The present study aimed to assess the occurrence of cancer and its association with exposure to sources of natural radioactivity using geological and geophysical information in the aforementioned state. The spatial dependence of pulmonary, breast, stomach, leukemia, and skin cancer cases with the location of radioisotope sources were analyzed using geoprocessing tools. The geoprocessing analysis showed a differential pattern of uranium emission throughout the state, with the highest emission from areas with pegmatites outcrops. A spatial dependency of cancer cases was shown (Moran index: 0.43; p < 0.01). Moreover, a higher rate of natural radioactivity-cancer cases was associated with the high-intensity natural radioactivity areas: odds ratio:1.21 (95% CI 1.20; 1.23), following the same pattern when separately compared the different related types of cancer. These results highlight the importance of natural radioactivity as a public health problem in the Brazilian environmental scenario, confirming the need for further studies as the first toward understanding and implementing health management strategies mitigating the exposures, especially in areas of environmental risk.


Assuntos
Neoplasias , Radioatividade , Radônio , Urânio , Humanos , Brasil/epidemiologia
7.
J. bras. pneumol ; 49(6): e20230210, 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1528912

RESUMO

ABSTRACT Exposure to radon can impact human health. This is a nonsystematic review of articles written in English, Spanish, French, or Portuguese published in the last decade (2013-2023), using databases such as PubMed, Google Scholar, EMBASE, and SciELO. Search terms selected were radon, human health, respiratory diseases, children, and adults. After analyzing the titles and abstracts, the researchers initially identified 47 studies, which were subsequently reduced to 40 after excluding reviews, dissertations, theses, and case-control studies. The studies have shown that enclosed environments such as residences and workplaces have higher levels of radon than those outdoors. Moreover, radon is one of the leading causes of lung cancer, especially in nonsmokers. An association between exposure to radon and development of other lung diseases, such as asthma and COPD, was also observed. It is crucial to increase public awareness and implement governmental control measures to reduce radon exposure. It is essential to quantify radon levels in all types of buildings and train professionals to conduct such measurements according to proven efficacy standards. Health care professionals should also be informed about this threat and receive adequate training to deal with the effects of radon on human health.


RESUMO A exposição ao radônio pode ter impacto na saúde humana. Esta é uma revisão não sistemática de artigos escritos em inglês, espanhol, francês ou português publicados na última década (2013-2023), utilizando bancos de dados como PubMed, Google Acadêmico, EMBASE e SciELO. Os termos de busca selecionados foram radônio, saúde humana, doenças respiratórias, crianças e adultos. Após a análise dos títulos e resumos, os pesquisadores inicialmente identificaram 47 estudos, que foram posteriormente reduzidos para 40 após a exclusão de revisões, dissertações, teses e estudos de caso-controle. Os estudos mostraram que ambientes fechados como residências e locais de trabalho apresentam maiores níveis de radônio do que ambientes externos. Além disso, o radônio é uma das principais causas de câncer de pulmão, especialmente em não fumates. Também foi observada associação entre exposição ao radônio e desenvolvimento de outras doenças pulmonares, como asma e DPOC. É crucial aumentar a conscientização do público e implementar medidas governamentais de controle para reduzir a exposição ao radônio. É fundamental quantificar os níveis de radônio em todos os tipos de edifícios e treinar profissionais para realizar essas medições segundo padrões de eficácia comprovada. Os profissionais de saúde também devem ser informados sobre essa ameaça e receber formação adequada para lidar com os efeitos do radônio na saúde humana.

8.
Environ Monit Assess ; 195(1): 149, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36434308

RESUMO

Rural and isolated communities traditionally lack adequate water treatment and distribution systems, and water quality assessment often does not include radioactivity measurement. Here we present, for the first time, the results of Rn measurements and the evaluation of the associated dose in groundwaters of rural communities in a semiarid area in Paraiba State, Brazil. Water samples were analysed using a low-level liquid scintillation spectrometer (LSS). Radon concentrations were higher than EPA and WHO recommended levels in water for most of the wells (range of 5.5-1107.0 Bq/L, average 252.8 Bq/L). Higher Rn concentration was measured in deeper wells and located in area rich in granite and diorite rocks. The annual effective doses varied between 0.021 and 4.317 mSv/y for infants, 0.016-3.182 mSv/y for children, and 0.015-3.022 mSv/y for adults, exceeding, in some cases, the 1 mSv/y reference level recommended by the WHO and UNSCEAR for the public. Thus, water consumption from half of the wells should be avoided unless adequate treatment is provided. Results highlight the need to perform actions to supply water with appropriate quality to the local population.


Assuntos
Água Subterrânea , Poluentes Radioativos da Água , Adulto , Criança , Lactente , Humanos , Poluentes Radioativos da Água/análise , População Rural , Brasil , Monitoramento Ambiental/métodos , Água Subterrânea/análise
9.
Appl Radiat Isot ; 187: 110319, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35752113

RESUMO

Radon and progeny are potentially relevant in radioecological studies, as they contribute more than half of the exposure to environmental radiation. The investigation of 222Rn in internal environments of municipalities of Paraíba and Rio Grande do Norte in Brazil was carried out using passive dosimetry with α Espec-222, installed in environments selected by the history of natural radiative occurrences. The monitoring time was eight months to consider seasonal influence. Concentrations from 26.91 to 316.35 Bq m-3 were obtained, with a maximum effective dose of almost 8 mSv y-1. The influence on households exceeds, by almost 31%, the average obtained for occupational environments. The municipalities of Paraíba presented higher results for Rn, with an average of almost 176 Bq m-3 and an effective dose greater than 4 mSv y-1. The application of individual occupancy factors for home and work environments made it possible to combine the dosimetric models, making the scenario closer to the real exposure of individuals who work and reside in the same municipality, with a dosimetric response of 21.45% lower than the model used worldwide. The different scenarios applied allowed expanding the radiometry of the environments, generating a database that precedes studies of environmental and radioecological impacts, strengthening security and enabling new works to interpret public health problems in search of joint and shared solutions.


Assuntos
Poluentes Radioativos do Ar , Poluição do Ar em Ambientes Fechados , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Radiação de Fundo , Brasil , Humanos , Monitoramento de Radiação/métodos , Radônio/análise
10.
J Environ Radioact ; 249: 106891, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35537371

RESUMO

Radon gas concentrations in ferruginous, quartzitic/conglomeratic and carbonatic caves were measured and the results obtained in each lithology were compared. Three representatives of each formation (nine caves in total) were studied. The caves are located in three environmental preserved areas in the Ferriferous-Aquifer Quadrangle and in its regional surrounding, in the center-south portion of Minas Gerais State, Brazil. It was found that the average concentration in quartzitic/conglomeratic caves (4,759 Bq/m3) was much higher than those obtained in carbonatic (844 Bq/m3) and ferruginous (945 Bq/m3) caves. This result most likely reflects differences in the uranium content of the rock types. Also, for a better understanding of the radon distribution inside the caves, concentration maps with their interpolated values were generated using geospatial analysis tools.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Radônio , Radônio/análise , Poluentes Radioativos do Ar/análise , Monitoramento de Radiação/métodos , Brasil
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