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1.
Wei Sheng Yan Jiu ; 53(2): 294-299, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38604967

RESUMO

OBJECTIVE: To establish an analytical method for determining the migration of 24 elements in Yixing clay pottery in 4% acetic acid simulated solution by inductively coupled plasma mass spectrometry. METHODS: Four types of Yixing clay pottery, including Yixing clay teapot, Yixing clay kettle, Yixing clay pot, and Yixing clay electric stew pot, were immersed in 4% acetic acid as a food simulant for testing. The migration amount of 24 elements in the migration solution was determined using inductively coupled plasma mass spectrometry. RESULTS: Lithium, magnesium, aluminum, iron, and barium elements with a mass concentration of 1000 µg/L; Lead, cadmium, total arsenic, chromium, nickel, copper, vanadium, manganese, antimony, tin, zinc, cobalt, molybdenum, silver, beryllium, thallium, titanium, and strontium elements within 100 µg/L there was a linear relationship within, the r value was between 0.998 739 and 0.999 989. Total mercury at 5.0 µg/L, there was a linear relationship within, the r value of 0.995 056. The detection limit of the elements measured by this method was between 0.5 and 45.0 µg/L, the recovery rate was 80.6%-108.9%, and the relative standard deviation was 1.0%-4.8%(n=6). A total of 32 samples of four types of Yixing clay pottery sold on the market, including teapots, boiling kettles, casseroles, and electric stewing pots, were tested. It was found that the migration of 16 elements, including beryllium, titanium, chromium, nickel, cobalt, zinc, silver, cadmium, antimony, total mercury, thallium, tin, copper, total arsenic, molybdenum, and lead, were lower than the quantitative limit. The element with the highest migration volume teapot was aluminum, magnesium, and barium; The kettle was aluminum and magnesium; Casserole was aluminum, magnesium, and lithium; The electric stew pot was aluminum. CONCLUSION: This method is easy to operate and has high accuracy, providing an effective and feasible detection method for the determination and evaluation of element migration in Yixing clay pottery.


Assuntos
Arsênio , Mercúrio , Oligoelementos , Cobre , Molibdênio/análise , Níquel , Argila , Magnésio , Alumínio/análise , Cádmio/análise , Bário/análise , Titânio/análise , Prata/análise , Berílio/análise , Estanho/análise , Arsênio/análise , Lítio/análise , Antimônio/análise , Tálio/análise , Zinco , Cromo , Cobalto/análise , Mercúrio/análise , Espectrometria de Massas , Acetatos , Oligoelementos/análise
2.
Lasers Surg Med ; 56(3): 263-269, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38282099

RESUMO

OBJECTIVES: Pulsed laser treatment of melasma has shown some promising results. To compare the effectiveness and safety of 755-nm picosecond alexandrite laser (PSAL) fitted with diffractive lens array (DLA) versus 1064-nm Q-switched neodynimum:yttrium aluminum garnet laser (QSNYL) for the treatment of melasma. METHODS: We conducted a randomized, split face controlled, 2-year follow-up study. Each face was divided into two parts, each side receiving three treatments with either PSAL or QSNYL at 1 month intervals. Modified Melasma Area Severity Index scores (mMASI), pain scores, patient satisfaction and adverse events were recorded. In vivo reflectance confocal microscopy (RCM) images were acquired. RESULTS: Twenty subjects were enrolled and three dropped out. At 6 months, mMASI scores were significantly lower than baseline for QSNYL sides (p = 0.022), with no statistically significant difference between PSAL sides before and after treatment, PSAL sides versus QSNYL sides, or patient satisfaction scores. QSNYL treatment was associated with less pain (p = 0.014). No serious adverse events were reported. In the PSAL sides RCM showed a large number of dendritic melanocytes infiltrated in the dermis at 2 weeks and 4 weeks after treatment. Ten patients (58.82%) reported recurrence or exacerbation at 2-year follow-up with no statistically significant difference between the two lasers. CONCLUSIONS: QSNYL demonstrated short term clinical efficacy for melasma, but did not provide any additional benefit compared to PSAL with DLA. QSNYL was associated with less pain. There was a high recurrence rate at 2-year follow-up. RCM allowed the detection of cellular changes in melasma lesions.


Assuntos
Berílio , Lasers de Estado Sólido , Melanose , Humanos , Seguimentos , Lasers de Estado Sólido/uso terapêutico , Melanose/radioterapia , Resultado do Tratamento , Dor
3.
J Occup Environ Med ; 66(3): 247-251, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38151991

RESUMO

OBJECTIVE: The aim of the study is to investigate the cause of death among individuals diagnosed with chronic beryllium disease (CBD) or beryllium sensitization (BeS). METHODS: Vital status, cause of death, and standardized mortality ratios for the underlying cause of death were determined for a cohort of 354 individuals with CBD and 290 individuals with BeS. RESULTS: Among 216 deceased individuals, 153 had CBD and 63 had BeS. Nonmalignant respiratory deaths and other causes of death were significantly increased among those with CBD. No cause of death was significantly increased for BeS. Mortality from lung cancer was not increased. CONCLUSIONS: Individuals with CBD had an overall increased mortality risk due to increased respiratory mortality regardless of their duration of exposure to beryllium. Individuals with BeS did not have increased respiratory mortality. No increased risk of lung cancer was seen among this cohort.


Assuntos
Ácidos Alcanossulfônicos , Beriliose , Exposição Ocupacional , Humanos , Berílio/efeitos adversos , Beriliose/etiologia , Doença Crônica , Exposição Ocupacional/efeitos adversos
4.
PLoS One ; 18(12): e0294080, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38060542

RESUMO

The X-ray energy spectrum is crucial for image quality and dosage assessment in mammography, radiography, fluoroscopy, and CT which are frequently used for the diagnosis of many diseases including but not limited to patients with cardiovascular and cerebrovascular diseases. X-ray tubes have an electron filament (cathode), a tungsten/rubidium target (anode) oriented at an angle, and a metal filter (aluminum, beryllium, etc.) that may be placed in front of an exit window. When cathode electrons meet the anode, they generate X-rays with varied energies, creating a spectrum from zero to the electrons' greatest energy. In general, the energy spectrum of X-rays depends on the electron beam's energy (tube voltage), target angle, material, filter thickness, etc. Thus, each imaging system's X-ray energy spectrum is unique to its tubes. The primary goal of the current study is to develop a clever method for quickly estimating the X-ray energy spectrum for a variety of tube voltages, filter materials, and filter thickness using a small number of unique spectra. In this investigation, two distinct filters made of beryllium and aluminum with thicknesses of 0.4, 0.8, 1.2, 1.6, and 2 mm were employed to obtain certain limited X-ray spectra for tube voltages of 20, 30, 40, 50, 60, 80, 100, 130, and 150 kV. The three inputs of 150 Multilayer Perceptron (MLP) neural networks were tube voltage, filter type, and filter thickness to forecast the X-ray spectra point by point. After training, the MLP neural networks could predict the X-ray spectra for tubes with voltages between 20 and 150 kV and two distinct filters made of aluminum and beryllium with thicknesses between 0 and 2 mm. The presented methodology can be used as a suitable, fast, accurate and reliable alternative method for predicting X-ray spectrum in medical applications. Although a technique was put out in this work for a particular system that was the subject of Monte Carlo simulations, it may be applied to any genuine system.


Assuntos
Alumínio , Berílio , Humanos , Raios X , Radiografia , Redes Neurais de Computação , Método de Monte Carlo
5.
Physiol Plant ; 175(5): e14036, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37882304

RESUMO

Elevated CO2 (eCO2 ) is one of the climate changes that may benefit plant growth under emerging soil contaminants such as heavy metals. In this regard, the morpho-physiological mechanisms underlying the mitigating impact of eCO2 on beryllium (Be) phytotoxicity are poorly known. Hence, we investigated eCO2 and Be interactive effects on the growth and metabolism of two species from different groups: cereal (oat) and legume (alfalfa). Be stress significantly reduced the growth and photosynthetic attributes in both species, but alfalfa was more susceptible to Be toxicity. Be stress induced reactive oxygen species (ROS) accumulation by increasing photorespiration, subsequently resulting in increased lipid and protein oxidation. However, the growth inhibition and oxidative stress induced by Be stress were mitigated by eCO2 . This could be explained, at least partially, by the increase in organic acids (e.g., citric acid) released into the soil, which subsequently reduced Be uptake. Additionally, eCO2 reduced cellular oxidative damage by reducing photorespiration, which was more significant in alfalfa plants. Furthermore, eCO2 improved the redox status and detoxification processes, including phytochelatins, total glutathione and metallothioneins levels, and glutathione-S-transferase activity in both species, but to a greater extend in alfalfa. In this context, eCO2 also stimulated anthocyanin biosynthesis by accumulating its precursors (phenylalanine, coumaric acid, cinnamic acid, and naringenin) and key biosynthetic enzymes (phenylalanine ammonia-lyase, cinnamate hydroxylase, and coumarate:CoA ligase) mainly in alfalfa plants. Overall, this study explored the mechanistic approach by which eCO2 alleviates the harmful effects of Be. Alfalfa was more sensitive to Be stress than oats; however, the alleviating impact of eCO2 on Be stress was more pronounced in alfalfa.


Assuntos
Dióxido de Carbono , Medicago sativa , Dióxido de Carbono/farmacologia , Dióxido de Carbono/metabolismo , Medicago sativa/metabolismo , Avena/metabolismo , Berílio , Estresse Oxidativo , Plantas/metabolismo , Glutationa/metabolismo , Solo
6.
Photobiomodul Photomed Laser Surg ; 41(9): 509-511, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37668739

RESUMO

Background: Alexandrite 755 nm laser has been currently recognized one of the gold standards for the permanent hair removal business because of its sufficient tissue penetration and higher affinity for melanin compared with Nd:YAG, making the treatment more incisive and effective. Objective: In this study, we evaluated an Alexandrite 755 nm laser with a 30-mm spot for a new and fast hair removal treatment. Methods: Patients of both genders, with skin Fitzpatrick's types, ranging from II to III, were asked to avoid any epilation techniques 4 weeks before the laser hair removal session. Participants underwent a minimum of three to a maximum of eight sessions of treatment, every 6 weeks. Six months after the last treatment, the final evaluation was completed. The treated body areas included arms, legs, axillae, and trunk. The subjects used a numeric scale with a range of 0 to 10 (0: no pain, 10: unbearable), to indicate the associated pain level experienced. By comparing the percentage of terminal hairs before and after laser treatment, hair reduction was determined. Results: The patients reported only slight post-treatment erythema that disappeared after a few hours and only two patients showed persistent erythema lasting a few weeks. The pain was found to be 4.9 ± 0.9 after single pass emission. Conclusions: The 755 nm laser with the new handpiece has proven to be an ideal wavelength for hair removal, allowing efficient, safe, and faster treatments to be performed for the patient.


Assuntos
Lasers de Estado Sólido , Humanos , Feminino , Masculino , Lasers de Estado Sólido/uso terapêutico , Berílio , Cabelo , Perna (Membro)
8.
Mar Pollut Bull ; 194(Pt B): 115353, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37572432

RESUMO

The atmospheric bulk depositional fluxes of 210Pb were measured at a station on the Adriatic coast, Croatia over 4 years period from March 2017 to December 2020. The monthly depositional fluxes followed oceanic deposition patterns with a lower flux between 0.0735 and 16.9 Bq m-2 month-1. The volume-weighted activities were 0.000514 and 1.35 Bq L-1 and decreased with increasing precipitation. A clear seasonal trend was observed with higher depositional flux in autumn and minimum value in the winter season. The average annual bulk depositional flux and volume-weighted activities of 210Pb were 73.8 Bq m-2 y-1 and 0.119 Bq L-1 respectively. The precipitation normalized enrichment factor (α) indicates higher depositional fluxes of 210Pb during summer and spring than desired value according to the amount of precipitation. We found that the 210Pb depositional fluxes in the coastal stations are lower due to 210Pb-depleted oceanic air masses and increase with the amount of precipitation.


Assuntos
Poluentes Radioativos do Ar , Radioisótopos de Chumbo , Radioisótopos de Chumbo/análise , Chumbo , Croácia , Berílio/análise , Poluentes Radioativos do Ar/análise , Estações do Ano , Monitoramento Ambiental
9.
Appl Radiat Isot ; 200: 110961, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37531730

RESUMO

In digital subtraction angiography (digital subtraction total cerebral angiography), cardiac and macrovascular cardiography, anorectal radiology, fluoroscopy, and computed tomography (CT), a prior knowledge to X-ray energy spectrum is crucial for assessing the image quality and also calculating patient X-ray dosage. The present investigation's main objective is to propose an intelligent technique for faster calculating X-ray energy spectrum of medical imaging systems with different exposure settings of tube voltage, filter material, and thickness based on limited specific spectra. In this study, Monte Carlo N Particle (MCNP) simulation code was initially used to generate some limited X-ray spectra for tube voltages of 20, 30, 40, 50, 80, 100, 130, and 150 kV for two different filters of beryllium and aluminum with thicknesses of 0. 4, 0.8, 1.2, 1.6 and 2 mm. Tube voltage, type, and thickness of filter were used as the 3 inputs of 150 Radial Basis Function Neural Network (RBFNN) to forecast point by point of the X-ray spectrum. After training, the RBFNNs could forecast most of the X-ray spectra for tube voltages in the range of 20-150 kV and two various filters of aluminum and beryllium with thicknesses in the range of 0-2 mm.


Assuntos
Alumínio , Berílio , Humanos , Raios X , Radiografia , Redes Neurais de Computação , Imagens de Fantasmas , Doses de Radiação , Método de Monte Carlo
11.
Med. segur. trab ; 69(271): 108-123, 30 jun 2023. tab
Artigo em Espanhol | IBECS | ID: ibc-228167

RESUMO

Introducción: El berilio es un metal que por sus propiedades físico-químicas es utilizado en la industria para la fabricación de diferentes productos comerciales y de alta tecnología. La exposición laboral al berilio se relaciona con la aparición de neoplasia de pulmón, siendo esta enfermedad la primera causa de muerte por cáncer a nivel mundial.Objetivos: Revisar la literatura científica existente en relación con la exposición laboral al berilio y/o sus compues-tos y la neoplasia de pulmón.Método: Revisión sistemática de la literatura científica recogida en las bases de datos bibliográficas MEDLINE (vía PubMed), EMBASE, Web Of Science, Scopus, Cochrane Library, Índice Bibliográfico Español en Ciencias de la Salud (IBECS), Literatura Latinoamericana y del Caribe en Ciencias de la Salud (LILACS) y Medicina en Español (MEDES). Los términos utilizados como descriptores fueron: “Occupational Exposure”, “Occupational Diseases”, “Beryllium” y “Lung Neoplasms”. La búsqueda se completó con otros términos en texto libre y no se emplearon filtros (límites). La determinación de la calidad de los artículos seleccionados se llevó a cabo empleando la guía STROBE.Resultados: Se recuperaron 180 referencias, de las que se seleccionaron a texto completo 11 artículos tras aplicar los criterios de inclusión y exclusión. En estos estudios se describe la asociación entre exposición laboral al berilio y el desarrollo de neoplasia de pulmón.Conclusiones: Existe una asociación entre la exposición laboral al berilio y/o sus compuestos y la neoplasia de pulmón. Considerando el bajo número de estudios publicados y sus limitaciones, sería necesario realizar nuevos estudios que se adapten a las condiciones de la industria actual del berilio, teniendo en cuenta la solubilidad de sus compuestos, así como la identificación de sectores industriales y colectivos de trabajadores expuestos al mismo que aún no hayan sido estudiados (AU)


Introduction: Beryllium is an element that, due to its physical and chemical characteristics, is used in the manufac-turing of different commercial products and the high-tech industry. Laboral exposure to beryllium is associated with higher incidence of lung cancer, being this disease the leading cause of cancer death worldwide.Objectives: To review the existing scientific literature on the occurrence of occupational exposure to beryllium and/or its compounds and lung cancer.Method: Systematic review of the scientific literature collected in the bibliographic databases MEDLINE (via PubMed), EMBASE, Web Of Science, Scopus, Cochrane Library, Spanish Bibliographic Index in Health Sciences (IBECS), Latin American and Caribbean Literature in Health Sciences (LILACS) and Medicine in Spanish (MEDES). The terms used as descriptors were: “Occupational Exposure”, “Occupational Diseases”, “Beryllium” and “Lung Neo-plasms”. The search was completed with other terms in free text and no filters (limits) were used. The determination of the quality of the selected articles was carried out using the STROBE guide.Results: 180 references were retrieved, of which 11 articles could be obtained in full text after applying the inclusion and exclusion criteria. These studies describe the association between occupational exposure to beryllium and the development of lung cancer.Conclusions: There is an association between exposure to beryllium and/or its compounds and the development of lung cancer. However, considering the low number of published studies and their limitations, further studies should be carried out, which may be adapted to the current circumstances of the beryllium industry, taking into account the solubility of the beryllium compounds and the identification of industries and populations of workers exposed to beryllium that have not yet been studied (AU)


Assuntos
Humanos , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Neoplasias Pulmonares/induzido quimicamente , Berílio/efeitos adversos
12.
Environ Sci Pollut Res Int ; 30(60): 125241-125253, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37140871

RESUMO

The treatment of beryllium wastewater has become a major problem in industry. In this paper, CaCO3 is creatively proposed to treat beryllium-containing wastewater. Calcite was modified by an omnidirectional planetary ball mill by a mechanical-chemical method. The results show that the maximum adsorption capacity of CaCO3 for beryllium is up to 45 mg/g. The optimum treatment conditions were pH = 7 and the amount of adsorbent was 1 g/L, and the best removal rate was 99%. The concentration of beryllium in the CaCO3-treated solution is less than 5 µg/L, which meets the international emission standard. The results show that the surface co-precipitation reaction between CaCO3 and Be (II) mainly occurs. Two different precipitates are generated on the used-CaCO3 surface; one is the tightly connected Be (OH)2 precipitation, and the other is the loose Be2(OH)2CO3 precipitation. When the pH of the solution exceeds 5.5, Be2+ in the solution is first precipitated by Be (OH)2. After CaCO3 is added, CO32- will further react with Be3(OH)33+ to form Be2(OH)2CO3 precipitation. CaCO3 can be considered as an adsorbent with great potential to remove beryllium from industrial wastewater.


Assuntos
Carbonato de Cálcio , Águas Residuárias , Berílio , Adsorção , Concentração de Íons de Hidrogênio , Cinética
13.
Chemosphere ; 326: 138439, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36935057

RESUMO

The release of highly toxic beryllium in sludge (BCS) produced by physico-chemical treatment of beryllium-containing wastewater from Be smelting production has become a growing concern with the widespread use of Be in the defense industry. This work investigated the potential mobility of Be in BCS. The toxicity characteristic leaching procedure (TCLP) of BCS showed that the amount of leached Be was up to 202 mg L-1, which exceeded the regulated limit by nearly 10,000 times. The chemical fractionation analysis further revealed that the excessive amount of Be leached from BCS was contributed to the high content of acid-soluble fraction and reducible fraction of Be, which accounted for over 70% of the Be content. The results obtained from mineralogical automatic analyzer (MLA) showed that gypsum (23.23%) and epidote (19.55%) were the two major mineralogical phases of BCS. Both were small and loosely structured agglomerated particles with a D50 of 6.61 µm and 3.31 µm. ToF-SIMS results revealed that the Be distribution on the surface of BCS particles was relatively dispersed, with no aggregation or encapsulation. Be co-precipitated with gypsum and chlorite in the form of unstable Be(OH)2, which attached to the surface of these small particles. The unstable state of Be and the small size, loose structure and high liberation of the host material phases are the main reasons for the high leaching mobility of Be. The results of the risk assessment indicated that BCS posed an extremely high potential ecological risk, with Be being the most significant contributor.


Assuntos
Metais Pesados , Esgotos , Esgotos/química , Águas Residuárias , Metais Pesados/análise , Berílio , Sulfato de Cálcio
14.
Radiat Prot Dosimetry ; 199(6): 540-551, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-36908190

RESUMO

The manganese salt bath is considered a primary standard for determining the absolute emission rate of radionuclide neutron sources. The National Research Council of Canada has recently revived its manganese salt bath and a full description of the system is given here. The physical characteristics of the bath, as well as the methods for determining the efficiency of the bath system and the induced activity in the bath, are described. An in-depth analysis of the fraction of neutrons captured in the manganese and the correction factor for neutron losses is also provided. Finally, the results of emission rate measurements of four different sources, complete with an uncertainty budget, are given. The emission rates of three americium-beryllium neutron sources and one californium-252 neutron source were found to agree with the known values, within a standard uncertainty of 1.7%.


Assuntos
Califórnio , Manganês , Doses de Radiação , Calibragem , Califórnio/análise , Nêutrons , Amerício/análise , Berílio/análise , Canadá , Radiometria/métodos
15.
PLoS One ; 18(3): e0281835, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36893140

RESUMO

Topography is commonly viewed as a passive backdrop on which vegetation grows. Yet, in certain circumstances, a bidirectional feedback may develop between the control of topography and the spatial distribution of vegetation and landform development, because vegetation modulates the erosion of the land surface. Therefore, if reinforcing feedbacks are established between erosion and land cover distribution over timescales relevant to landform development, then the interactions between vegetation and topography may create distinctive landforms, shaped by vegetation. We expose here a strong correlation between the spatial distribution of vegetation, erosion rates, and topography at a characteristic length scale of 102-103m (mesoscale topography) in the Luquillo Experimental forest (LEF) of Puerto Rico. We use high-resolution LiDAR topography to characterize landforms, satellite images to classify the vegetation into forest types, and in-situ produced cosmogenic 10Be in the quartz extracted from soils and stream sediments to document spatial variations in soil erosion. The data document a strong correlation between forest type and topographic position (hilltop vs. valleys), and a correlation between topographic position and 10Be-derived erosion rates over 103-104 years. Erosion is faster in valleys, which are mostly covered by monocot Palm Forest, and slower on surrounding hills mostly covered by the dicot Palo Colorado Forest. Transition from one forest type to the next occurs across a break-in-slope that separates shallowly convex hilltops from deeply concave valleys (coves). The break-in-slope is the consequence of a longer-lasting erosional imbalance whereby coves erode faster than hills over landscape-shaping timescales. Such a deepening of the coves is usually spurred by external drivers, but such drivers are here absent. This implies that cove erosion is driven by a process originating within the coves themselves. We propose that vegetation is the primary driver of this imbalance, soil erosion being faster under Palm forest than under Palo Colorado forest. Concentration of the Palm forest in the deepening coves is reinforced by the better adaptation of Palm trees to the erosive processes that take place in the coves, once these develop steep slopes. At the current rate of landscape development, we find that the imbalance started within the past 0.1-1.5 My. The initiation of the process could correspond to time of settlement of these mountain slopes by the Palm and Palo Colorado forests.


Assuntos
Berílio , Radioisótopos , Floresta Úmida , Florestas , Solo
16.
Environ Pollut ; 323: 121277, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36796668

RESUMO

The fragile ecosystems of plateau lakes are in face of ecological risks from emerging toxic elements. Beryllium (Be) and thallium (Tl) have been considered priority control metals in recent years owing to their persistence, toxicity, and bioaccumulation. However, the toxic factors of Be and Tl are scarce and ecological risks of them in the aquatic environment were seldom investigated. Hence, this study developed a framework for calculating the potential ecological risk index (PERI) of Be and Tl in aquatic systems and used it to assess the ecological risks of Be and Tl in Lake Fuxian, a plateau lake in China. The toxicity factors of Be and Tl were calculated to be 40 and 5, respectively. In sediments of Lake Fuxian, the concentrations of Be and Tl were between 2.18 and 4.04 mg/kg and 0.72-0.94 mg/kg, respectively. The spatial distribution indicated that Be was more abundant in the eastern and southern regions, and Tl had higher concentrations near the northern and southern banks, consistent with the distribution of anthropogenic activities. The background values were calculated as 3.38 mg/kg and 0.89 mg/kg for Be and Tl, respectively. In comparison with Be, Tl was more enriched in Lake Fuxian. The increasing Tl enrichment has been attributed to anthropogenic activities (e.g., coal burning and non-ferrous metal production), especially since the 1980s. Generally, Be and Tl contamination has decreased over the past several decades, from moderate to low, since the 1980s. The ecological risk of Tl was low, whereas Be might have caused low to moderate ecological risks. In the future, the obtained toxic factors of Be and Tl in this study can be adopted in assessing the ecological risks of them in sediments. Moreover, the framework can be employed for the ecological risk assessment of other newly emerging toxic elements in the aquatic environment.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Metais Pesados/análise , Lagos , Ecossistema , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Tálio/análise , China , Berílio , Medição de Risco
17.
J Environ Radioact ; 259-260: 107122, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36696867

RESUMO

An analysis of the concentration of 7Be in aerosol samples collected in one of the most polluted areas in Europe (Katowice and Krakow in southern Poland) indicated seasonal variability, with a maximum in the summer months. The average concentrations of 7Be were 4616.1 µBq m-3 in Katowice and 3259.4 µBq m-3 in Krakow, respectively, and they are among the highest values recorded in Poland in the studied period (1998-2016). These cities are also characterised by Poland's highest concentrations of 210Pb (547.8 µBq m-3 and 513.2 µBq m-3). The highest radioactive concentrations of 210Pb were observed in the winter and autumn, since in the case of these industrial areas, the combustion processes related to heating in the cold season of the year are an additional source of this isotope, next to its natural origin. The airborne particulate matter concentrations at both locations correlate with the concentrations of 210Pb. The average values of PM10 concentrations (71.1 µg m-3 in Krakow to 45.0 µg m-3 in Katowice), were 2-3 times higher than the average ones recorded in northern Poland. It has been proven that air temperature is the key parameter affecting the transport of isotopes, especially in the warm season of the year, when its increase causes increased thermal convection, leading to intense vertical mixing and exchange in the troposphere. Analyses using the machine learning method allowed for an indication of the correlation between relative humidity and atmospheric precipitation, as well as higher wind speed and concentrations of 7Be which is inversely proportional. Geographical factors (the latitude of the station and the land elevation) have no impact on near-surface concentrations of 7Be in Poland.


Assuntos
Poluentes Radioativos do Ar , Berílio , Radioisótopos de Chumbo , Material Particulado , Monitoramento de Radiação , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Chumbo/análise , Material Particulado/análise , Polônia , Estações do Ano
18.
J Trace Elem Med Biol ; 76: 127125, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36623420

RESUMO

PURPOSE: Beryllium is known to have adverse health effects and is classified as carcinogenic to humans. However, data on systemic beryllium exposure in humans are rare and especially human toxicokinetics are largely uncharted. As such, the first reported multi-annual course of blood and urine concentrations after a high exposure scenario provides important new insights. METHODS: For a medical follow-up biomonitoring samples were collected for 56 months from a male subject after an accidental and multi-faceted high exposure. Sampling started on day 2 post-exposure for urine and day 147 for blood. The samples were analyzed by inductively coupled mass spectrometry (ICP-MS) and plotted longitudinally as a function of time. Terminal half-lives were calculated assuming a first-order elimination process. MAIN FINDINGS: Both matrices showed highly increased initial concentrations (about 100-fold), despite the 147-day delay in blood sampling, and a marked decline over time. In urine, a two-phase excretion process was suspected based on the longitudinal data. Calculations gave terminal half-lives of 117.5 days and 666.5 days for phases 1 and 2, respectively. Blood kinetics called for a terminal half-life of 103.5 days. Elimination kinetics in blood and urine were comparable, simultaneously gathered samples showed an excellent correlation (R² = 0.985). PRINCIPAL CONCLUSIONS: The long-term follow-up after a high initial exposure to beryllium provides the first detailed insights into the elimination course of systemically available beryllium in humans. Conform kinetics of beryllium in urine and blood and the strong correlation between both parameters indicate high data validity and support the good representation of the current systemically available beryllium by urine and blood concentration in humans. The relatively long terminal half-lives in both matrices suggest a possible accumulation in humans in case of repeated exposures.


Assuntos
Berílio , Monitoramento Biológico , Humanos , Masculino , Berílio/toxicidade , Berílio/urina , Toxicocinética , Espectrometria de Massas/métodos
19.
Environ Pollut ; 320: 121077, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36646409

RESUMO

Beryllium (Be) is a relatively rare element and occurs naturally in the Earth's crust, in coal, and in various minerals. Beryllium is used as an alloy with other metals in aerospace, electronics and mechanical industries. The major emission sources to the atmosphere are the combustion of coal and fossil fuels and the incineration of municipal solid waste. In soils and natural waters, the majority of Be is sorbed to soil particles and sediments. The majority of contamination occurs through atmospheric deposition of Be on aboveground plant parts. Beryllium and its compounds are toxic to humans and are grouped as carcinogens. The general public is exposed to Be through inhalation of air and the consumption of Be-contaminated food and drinking water. Immobilization of Be in soil and groundwater using organic and inorganic amendments reduces the bioavailability and mobility of Be, thereby limiting the transfer into the food chain. Mobilization of Be in soil using chelating agents facilitates their removal through soil washing and plant uptake. This review provides an overview of the current understanding of the sources, geochemistry, health hazards, remediation practices, and current regulatory mandates of Be contamination in complex environmental settings, including soil and aquatic ecosystems.


Assuntos
Berílio , Poluentes do Solo , Humanos , Ecossistema , Solo , Poluentes do Solo/análise , Gestão de Riscos , Carvão Mineral
20.
Environ Sci Pollut Res Int ; 30(7): 18340-18353, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36208374

RESUMO

Lotus leaf was used as raw material to prepare HNO3-activated carbon with 1.5:1 (HNO3:lotus leaf) (wt:wt) impregnation. Then, the activated carbon was modified by Fe(NO3)3 to obtain Fe-activated carbon (Fe-AC). The adsorption test results show that Fe-AC maximum saturated adsorption capacity (Qm) is 45.68 mg/g when the Fe(NO3)3 loading is 5% of the total activated carbon, pH = 6, and the temperature is 35 ℃. The adsorption effect of Fe-AC under neutral conditions is better than that under alkaline and acidic conditions. The modified activated carbon has better adsorption selectivity. The obtained material (Fe-AC) was characterized by N2 adsorption-desorption isotherm, SEM, FT-IR, BET, XRD, XPS, and pHpzc. The total pore volume, specific surface area, and zero charges of modified activated carbon were increased. The types of modified functional groups were reduced, and the iron reacted with the functional groups, providing ion exchange sites for the adsorption of beryllium. The adsorption thermodynamics showed that the adsorption process was spontaneous and endothermic. The adsorption mechanism of Fe-AC to beryllium is mainly chemical adsorption.


Assuntos
Lotus , Poluentes Químicos da Água , Adsorção , Carvão Vegetal/química , Berílio , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Poluentes Químicos da Água/análise , Cinética , Concentração de Íons de Hidrogênio
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