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1.
J Hazard Mater ; 465: 133314, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38147747

RESUMO

This study investigated the influence of beverage packaging materials on the presence of endocrine disrupting chemicals (EDCs) in plastic, glass, carton, aluminium, and tin canned non-alcoholic beverages. Results showed that 63 EDCs including perfluoroalkyl and polyfluoroalkyl substances (PFAS), bisphenols, parabens, benzophenone-type UV-filters, biocides, nitrophenols, and alkylphenols, were detected in 144/162 screened products. Detected ∑63EDC concentrations ranged from 1.3 to 19,600 ng/L. EDC concentrations were higher in beverages packaged in metal cans while lower or no levels were detected in glass, plastic, and carton packaged drinks. Bisphenol levels were higher on average in canned beverages compared to glass (p < 0.01) and plastic products (p < 0.05) produced by the same brand and manufacturer. Two structural isomers of bisphenol A (BPA) were identified in 19 beverages, constituting the first detection in foodstuffs. The calculated daily intake of detected EDCs showed that exposure to BPA from per capita beverage consumption of 364 mL/day are up to 2000-fold higher than the newly revised safety guideline for BPA recommended by the EFSA (European Food Safety Authority). Overall, these findings suggest that BPA exposure poses a potential health hazard for individuals who regularly consume non-alcoholic beverages packaged in aluminium or tin cans, particularly young children.


Assuntos
Disruptores Endócrinos , Criança , Humanos , Pré-Escolar , Alumínio , Estanho , Bebidas/análise , Medição de Risco , Compostos Benzidrílicos/análise
2.
Environ Sci Pollut Res Int ; 30(38): 89280-89292, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37452241

RESUMO

With a history of more than 200 years of tin mining, Bangka Island has brought along a byproduct of heavy minerals containing radionuclide elements. There are some concerns about this byproduct material contributing to natural radiation in the environment. In this study, a car-borne survey was conducted to accurately assess natural background radiation in Bangka Island. Indoor and outdoor ambient dose rates in 146 houses were also measured to assess the radiation dose from external exposure received by the public. Soil samples were collected and measured using a gamma spectroscopy system to evaluate the contributions of specific radionuclides to external terrestrial exposure. From 3790 measurement points during the car-borne survey, the highest ambient dose equivalent rate was 596 nSv h-1 measured in Muntok area, with a mean value of 101 nSv h-1 and a median value of 95 nSv h-1. The ambient dose equivalent rate distribution map showed a relatively higher value in the northern coastal area of the island, where the Pemali tin deposit is located. The annual effective dose received from external radiation in the 146 houses in Bangka Island ranged from 0.44 to 1.30 mSv year-1, with a median value of 0.66 mSv year-1. The soil contained a relatively high amount of thorium (232Th), which contributed 69% to external radiation exposure in Bangka Island.


Assuntos
Exposição à Radiação , Monitoramento de Radiação , Poluentes Radioativos do Solo , Doses de Radiação , Estanho , Automóveis , Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/análise , Tório/análise , Radioisótopos , Raios gama , Radiação de Fundo , Solo/química , Radioisótopos de Potássio/análise
3.
Angew Chem Int Ed Engl ; 62(25): e202302507, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37067196

RESUMO

Perovskite solar cells (PSCs) based on SnO2 electron transport layers have attracted extensive research due to their compelling photovoltaic performance. Herein, we presented an in situ passivation of SnO2 with low-cost hydroxyacid potassium synergist during deposition to optimize the interface carrier extraction and transport for high power conversion efficiency (PCE) and stabilities of PSCs. The orbital overlap of the carboxyl oxygen with the Sn atom alongwith the homogenous nano-particle deposition effectively suppresses the interfacial defects and releases the internal residual strains in the perovskite. Accordingly, a PCE of 24.91 % with a fill factor (FF) up to 0.852 is obtained for in situ passivated devices, which is one of the highest values for SnO2 -based PSCs. Moreover, the unencapsulated device maintained 80 % of its initial PCE at 80 °C over 600 h, 100 % PCE at ambient conditions for 1300 h, and 98 % after one week maximum power point tracking (MPPT) under continuous AM1.5G illumination.


Assuntos
Hidroxiácidos , Estanho , Óxidos , Potássio
4.
Artigo em Inglês | MEDLINE | ID: mdl-36231870

RESUMO

This article examines the impact of artisanal and small-scale mining (ASM) on livelihood in mining communities in Rwanda (Rutsiro) where wolframite and coltan are mined. The paper discusses the development of ASM and other entrepreneur activities, in particular agriculture. With ASM activities, there is environmental degradation on the one hand but also an improvement in the well-being of the local population on the other. The 3T (tin, tungsten, tantalum) minerals extracted by ASM are used in the electronics industry for products such as smartphones, tablets, and laptops, which are mainly consumed in the developed world. Based on questionnaires and structured research with miners, it was determined how ASM affects their lives, or whether there is a deterioration or improvement in their well-being. The research builds on previous field research in Rwanda. Because of mining, communities in the mining areas have access to health care, they can pay tuition fees, insurance, etc. On the other hand, the lives of miners are endangered by respiratory diseases, accidents in mines, landslides in mining areas, and other negative environmental impacts. The extraction of these minerals, however, may lead to a worse quality of life for the miners responsible for the extraction in developing countries. This different view is also illustrated by the fact that miners themselves often do not know what 3T minerals are used for. ASM benefits miners from an economic perspective but may worsen their quality of life due to unsuitable working conditions. This study covers a broader understanding of socioeconomic impacts of ASM and tries to point out the lack of awareness about the mining of minerals important for the daily use of modern technologies. This article would like to contribute to the larger debate about the lack of awareness of the origin of 3T minerals.


Assuntos
Mercúrio , Mineradores , Exposição Ocupacional , Ouro , Minerais , Qualidade de Vida , Ruanda , Tantálio , Estanho , Tungstênio
5.
Sci Rep ; 12(1): 17582, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266322

RESUMO

Knowledge of element concentrations in botanical extracts is relevant to assure consumer protection given the increased interest in plant-based ingredients. This study demonstrates successful multi-element investigations in order to address the lack of comprehensive profiling data for botanical extracts, while reporting for the first time the metallomic profile(s) of arnica, bush vetch, sweet cicely, yellow rattle, bogbean, rock-tea and tufted catchfly. Key element compositions were quantified using a validated HR-ICP-SFMS method (µg kg-1) and were found highly variable between the different plants: Lithium (18-3964); Beryllium (3-121); Molybdenum (75-4505); Cadmium (5-325); Tin (6-165); Barium (747-4646); Platinum (2-33); Mercury (5-30); Thallium (3-91); Lead (12-4248); Bismuth (2-30); Titanium (131-5827); Vanadium (15-1758); Chromium (100-4534); Cobalt (21-652); Nickel (230-6060) and Copper (1910-6340). Compendial permissible limits were not exceeded. Overall, no evidence of a health risk to consumers could be determined from consumption of the investigated plants at reasonable intake rates. Mathematical risk modelling (EDI, CDI, HQ, HI) estimated levels above safe oral thresholds only for Cd (16%) and Pb (8%) from higher intakes of the respective plant-derived material. Following high consumption of certain plants, 42% of the samples were categorised as potentially unsafe due to cumulative exposure to Cu, Cd, Hg and Pb. PCA suggested a potential influence of post-harvest processing on Cr, Ti and V levels in commercially-acquired plant material compared to wild-collected and farm-grown plants. Moreover, a strong correlation was observed between Pb-Bi, Be-V, Bi-Sn, and Tl-Mo occurrence. This study may support future research by providing both robust methodology and accompanying reference profile(s) suitable for the quality evaluation of essential elements and/or metal contaminants in botanical ingredients.


Assuntos
Cádmio , Chumbo , Mercúrio , Bário , Berílio/análise , Bismuto , Cádmio/análise , Cromo/análise , Cobalto , Cobre , Lítio , Mercúrio/análise , Molibdênio , Níquel/análise , Platina , Medição de Risco , Chá , Tálio , Estanho , Titânio , Vanádio/análise
6.
Artigo em Inglês | MEDLINE | ID: mdl-36141516

RESUMO

The treatment of arsenic (As) in tin tailings (TT) has been an urgent environmental problem, and stabilization/solidification (S/S) treatment is considered an effective technology to eliminate contamination of As. In this study, we developed a low-carbon and low-alkalinity material to S/S of As, and the results showed that the leaching concentration of As after treatment was lower than the Chinese soil environmental quality standard (0.1 mg/L). Based on a series of characterization tests, we found that OH- promoted the dissolution of As(III)-S, Fe-As(V), and amorphous As(III)-O species and formed Ca-As(III) and Ca-(V) species with Ca2+. Simultaneously, hydration produces calcium silicate hydrate (C-S-H) gel and ettringite by the form of adsorption and ion exchange to achieve S/S of As. We also assessed the durability of this material to acidity and temperature, and showed that the leaching concentration of As was below 0.1 mg/L at pH = 1-5 and temperature 20-60 °C. The method proposed in this study, S/S of As, has excellent effect and environmental durability, providing a new solution for harmless treatment of TT and its practical application.


Assuntos
Arsênio , Adsorção , Arsênio/química , Carbono/química , Solo , Estanho
7.
Biomater Adv ; 137: 212819, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35929256

RESUMO

Nanotechnology has immensely advanced the field of cancer diagnostics and treatment by introducing potential delivery vehicles as carriers for drugs or therapeutic agents. In due course, mesoporous silica nanoparticles (MSNs) have emerged as excellent vehicles for delivering drugs, biomolecules, and biomaterials, attributed to their solid framework and porosity providing a higher surface area for decorating with various functional ligands. Recently, the metal tin (Sn) has gained huge importance in cancer research owing to its excellent cytotoxicity and ability to kill cancer cells. In the present work, we synthesized MSNs, conjugated them with organotin compounds, and characterized them using various physicochemical techniques. Subsequently, the biological evaluation of MSN (S1), MSN-MP (S2) and tin-conjugated MSNs (S3: MSN-MP-SnPh3) (MP = 3-mercaptopropyltriethoxysilane) revealed that these nanoconjugates induced cytotoxicity, necrosis, and apoptosis in MCF-7 cells. Moreover, these nanoconjugates exhibited anti-angiogenic properties as demonstrated in the chick embryo model. The increase of reactive oxygen species (ROS) was found as a one of the plausible mechanisms underlying cancer cell cytotoxicity induced by these nanoconjugates, encouraging their application for the treatment of cancer. The tin-conjugated MSNs demonstrated less toxicity to normal cells compared to cancer cells. Furthermore, the genotoxicity studies revealed the clastogenic and aneugenic effects of these nanoconjugates in CHO cells mostly at high concentrations. These interesting observations are behind the idea of developing tin-conjugated MSNs as prospective candidates for anticancer therapy.


Assuntos
Antineoplásicos , Dióxido de Silício , Estanho , Animais , Embrião de Galinha , Cricetinae , Humanos , Antineoplásicos/farmacologia , Sobrevivência Celular , Cricetulus , Portadores de Fármacos/química , Nanoconjugados , Dióxido de Silício/química , Estanho/farmacologia
8.
Environ Sci Pollut Res Int ; 29(59): 89002-89013, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35841505

RESUMO

This study aims to assess breast cancer (BC) association with metals and whether polymorphisms in CYP1A1, CYP1B1, GSTM1 and GSTT1 act as confounders or as modifiers of those relationships. We performed a secondary analysis of 499 histologically confirmed BC cases and the same number of age-matched population controls. We measured urinary concentrations of 18 metals with mass spectrometry. We determined the genetic variants of interest by allelic discrimination and multiplex PCR. After adjusting for covariates, we found BC negatively associated with arsenic, barium, cobalt, copper, magnesium, molybdenum and vanadium concentrations and positively with those of caesium, manganese, tin and thallium. Most associations remained after stratifying by the genetic variants. We identified that polymorphisms in CYP1B1, CYP1A1 and GSTM1 genes interacted with some metals on BC: interaction p-values CYP1B1 G119T × antimony= 0.036, CYP1B1 G119T × cobalt <0.001, CYP1B1 G119T × tin= 0.032, CYP1A1 A4889G × aluminium= 0.018, CYP1A1 A4889G × arsenic= 0.031, CYP1A1 A4889G × nickel= 0.036, CYP1A1 A4889G × vanadium= 0.031 and GSTM1 deletion × barium= 0.035. Exposure to various individual metals, along with genetic characteristics may contribute to BC development. Further studies are warranted to confirm our results.


Assuntos
Neoplasias da Mama , Exposição Ambiental , Metais , Feminino , Humanos , Arsênio , Bário , Neoplasias da Mama/genética , Neoplasias da Mama/epidemiologia , Estudos de Casos e Controles , Cobalto , Citocromo P-450 CYP1A1/genética , Exposição Ambiental/efeitos adversos , Predisposição Genética para Doença , Genótipo , Glutationa Transferase/genética , Metais/efeitos adversos , México , Estanho , Vanádio
9.
Radiologia (Engl Ed) ; 64(3): 206-213, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35676052

RESUMO

OBJECTIVES: To assess image quality and radiation dose in computed tomography (CT) studies of the petrous bone done with a scanner using a tin filter, high-resolution detectors, and iterative reconstruction, and to compare versus in studies done with another scanner without a tin filter using filtered back projection reconstruction. MATERIAL AND METHODS: Thirty two patients (group 1) were acquired with an ultra-low dose CT (32-MDCT, 130kV, tin filter and iterative reconstruction). Images and radiation doses were compared to 36 patients (group 2) acquired in a 16-MDCT (120kV and filtered back-projection). Muscle density, bone density, and background noise were measured. Signal-to-noise ratio (SNR) was calculated. To assess image quality, two independent radiologists subjectively evaluated the visualization of the different structures of the middle and inner ear (0=not visualized, 3=perfectly identified and delimited). Interobserver agreement was calculated. Effective dose at different anatomical levels with the dose-length product was recorded. RESULTS: In the quantitative analysis, there were no significant differences in image noise between the two groups. In the qualitative analysis, a similar or slightly lower subjective score was obtained in the delimitation of different structures of the ossicular chain and cochlea in the 32-MDCT, compared to 16-MDCT, with statistically significant differences. Mean effective dose (±standard deviation) was 0.16±0.04mSv for the 32-MDCT and 1.25±0.30mSv for the 16-MDCT. CONCLUSIONS: The use of scanners with tin filters, high-resolution detectors, and iterative reconstruction allows to obtain images with adequate quality for the evaluation of the petrous bone structures with ultralow doses of radiation (0.16±0.04mSv).


Assuntos
Interpretação de Imagem Radiográfica Assistida por Computador , Estanho , Humanos , Osso Petroso/diagnóstico por imagem , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos
10.
Environ Sci Pollut Res Int ; 29(54): 81804-81829, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35739445

RESUMO

The groundwater resources of mining areas have been in a challenging condition in terms of metal pollution and human health. Therefore, this study investigated the concentration of cobalt (Co), molybdenum (Mo), selenium (Se), tin (Sn), and antimony (Sb) in groundwater samples (wells, qanats, and springs) in a heavily contaminated mining district, South Khorasan, Eastern Iran. Human health risk of the studied metals to target groups was assessed, and water quality of the studied groundwater was investigated in the study area. A total of 367 sampling sites (279 wells, 74 qanats, and 14 springs) in South Khorasan Province were selected to collect the groundwater samples from June to July 2020. Sampling was performed thrice for each sampling point, and hydrochemical parameters were evaluated using a portable multiparameter. Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect the metal concentrations. Results showed an order of Se > Mo > Sn > Co > Sb, and hazard index (HI) demonstrated a warning condition for south of South Khorasan (drinking application), southwest of South Khorasan (Irrigation application), and east and center of South Khorasan (drinking-irrigation application). Hydrochemical parameters showed a classification of "Na + K type" and "Mixed Ca-Mg-Cl type" with an overall group of "Na-Cl-HCO3" for sampled waters. Ficklin-Caboi diagram depicted a classification of "near-neutral low metal," and Schoeller diagram classified studied groundwater as "good" for drinking and irrigation consumptions and "Na-Cl" type based on ion balance diagram. Based on the correlation analysis, positive relationships were recorded among EC, TDS, Cl-, Na+, sulfate, Ca2+, salt, total hardness, Mg2+, ammonia, and K+ measured in the water samples. In essence, arid regions of the world greatly rely upon groundwater resources for drinking and irrigation consumptions, and mining districts with a heavy load of active mines can be a serious threat to the groundwater quality and human health.


Assuntos
Água Subterrânea , Selênio , Oligoelementos , Poluentes Químicos da Água , Humanos , Oligoelementos/análise , Selênio/análise , Antimônio/análise , Molibdênio/análise , Amônia/análise , Irã (Geográfico) , Estanho/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Água Subterrânea/química , Qualidade da Água , Medição de Risco , Sulfatos/análise , Cobalto/análise
11.
Acta Biomater ; 147: 414-426, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35598877

RESUMO

The Essure® permanent contraceptive implant, comprised of four alloys (nickel-titanium, 316L stainless steel, platinum-iridium, and tin-silver solder) and Dacron (PET) fibers, has been approved for use in the US for about two decades. However, little has been published on this implant's biomaterials performance, and as this implant gains interest in terms of in vivo performance, methods of implant post-retrieval storage also need to be assessed. This study investigated the electrochemical properties and ion release profile of Essure® during storage in phosphate buffered saline (PBS), 10 mM H2O2/PBS, a simulated inflammatory solution, and 10% neutral buffered formalin (NBF) to investigate the corrosion behavior and metal ion release. First, a galvanic test method was used to measure the galvanic interactions between alloys within the device. Second, an ion-release study over 107 days was performed. Ions were measured using inductively-coupled plasma mass spectrometry and the implants were assessed using digital optical microscopy, scanning electron microscopy, and energy dispersive x-ray spectrometry. The tin-silver (SnAg) solder continuously corroded in PBS and H2O2/PBS. In the presence of H2O2, nickel and titanium ions were released from the nickel-titanium (NiTi) coil, whereas release of these ions was minimal in PBS alone. Overall, corrosion of the SnAg solder, which holds the NiTi and 316L SS together, was significant in both PBS and H2O2/PBS and may result in loss of connection of the NiTi and 316L stainless steel portions of the implant. Storage in NBF exhibited very low corrosion rates for all alloys and low levels of ion release were observed indicating that formalin storage minimally affects the implant's corrosion status. STATEMENT OF SIGNIFICANCE: The Essure® device is an FDA premarket-approved female permanent sterilization device containing four different metal alloys and poly(ethylene terephthalate) polymer fibers. Significant concerns related to this device have been raised by the FDA since its introduction in 2002. This study is the first published in vitro work to specifically assess the corrosion mechanisms in this multi-alloy device and the role of different solution environments, including formalin storage, inorganic physiological saline and a simulated inflammatory condition. Significant evidence of corrosion of the tin-silver solder is documented, the release of Ni and Ti under simulated inflammatory conditions, and the relative inertness of storage of these implants in neutral buffered saline is presented. The tin-silver corrosion corroborates recent clinical evidence of tin corrosion products in tissues adjacent to these devices in vivo.


Assuntos
Dispositivos Anticoncepcionais Femininos , Corrosão , Falha de Equipamento , Ligas , Feminino , Formaldeído , Humanos , Peróxido de Hidrogênio , Teste de Materiais , Níquel/química , Polietilenotereftalatos , Solução Salina , Prata , Aço Inoxidável/química , Propriedades de Superfície , Estanho , Titânio/química
12.
Rocz Panstw Zakl Hig ; 72(4): 353-360, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34928111

RESUMO

BACKGROUND: Fruit and fruit products are important part of our daily diet. In addition to the ingredients necessary for the proper functioning of the body, these products can also be a source of intake elements harmful to human health. OBJECTIVE: Analysis of the results of monitoring studies conducted in Poland in 2015 concerning contamination of lead (Pb), cadmium (Cd), arsenic (As), mercury (Hg) and tin (Sn) in fruit and fruit products and exposure assessment. MATERIAL AND METHODS: Approximately 600 samples of fresh, frozen, dried fruits, fruit preserves and canned fruits were tested. The laboratories of State Sanitary Inspection were involved in testing. Accredited and validated analytical methods were used. The test samples were prepared in accordance with the standard PN-EN 13804:2013. The contents of lead, cadmium and tin were determined by using flame atomic absorption spectrometry (FAAS) or flameless with electrothermal atomization spectrometry (GFAAS); arsenic by using hydride generation atomic absorption spectrometry method (HGAAS) and mercury the "cold vapor" atomic absorption spectrometry (CVAAS) method. RESULTS: Contamination of investigated samples with elements harmful to human health (Pb, Ca, As, Hg and Sn does not rise concern to human health and was in most cases comparable with contamination reported in other European Union countries. The estimated average exposure of adults and children to lead intake with fruit and fruit products ranged from 0.5% to 14.6% of the respective Benchmark Dose Lower Confidence Limit (BMDL) established by the European Food Safety Authority (EFSA). The mean intake of cadmium with these groups of foodstuffs was in the range 0.3 - 8.5% of the TWI value (Tolerable Weekly Intake) established by EFSA for adults and children (0.1 - 3.6% of the PTMI (Provisional Tolerable Monthly Intake) established by JECFA. In case of arsenic mean intake was in the range 0.5 - 1.6% BMDL whilst for mercury (inorganic form) intake represented 0.5 - 1.4% of TWI value established by JECFA and then confirmed by EFSA. CONCLUSIONS: Based on the obtained results, it was found that content of Pb, Cd, As, Hg and Sn in the tested samples of fruit and their products does not pose a risk to consumer health. Estimated exposure of consumers does not exceed tolerable doses established by EFSA and JECFA for these elements.


Assuntos
Arsênio , Mercúrio , Cádmio , Criança , Frutas , Humanos , Chumbo , Estanho
13.
Bull Environ Contam Toxicol ; 107(6): 1032-1042, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34230989

RESUMO

A multi-medium system, involving tailing area (tailings, surrounding soils and water) and downstream agricultural area (river water, sediments and farmland soils), was conceived to evaluate the pollution status of potential toxic elements (PTEs, including Fe, Mn, Ni, Cu, Zn, As, Sn, Pb, Cr and Cd) and environmental risks in a tin-polymetallic mine area southwest China. The results indicated that tailings exhibited representative enrichment and combination characteristics of Sn, Cu, Ni, Fe, As, Pb and Cr compared to surrounding soils. Acid mine drainage (AMD) from tailings and other mining-related sources greatly affected river water and farmland soils, resulting in soil acidification and accumulation of Sn, As, Cu and Pb in paddy soils. Overall, potential ecological risks posed by tailings and river sediments, and pollution risks from Cu, As and Pb in farmland should be concerned. Therefore, effective measures should be urgently taken to prevent PTEs and AMD into surrounding environmental media.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Poluição Ambiental/análise , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise , Estanho
14.
J Photochem Photobiol B ; 210: 111965, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32739665

RESUMO

In the present study, chemical reaction method is used to synthesis zinc oxide (ZnO) nanostructures concurrently doped with tin and fluorine and investigated for the enhanced bacterial inhibition and photocatalytic degradation. The optical, structural, compositional morphological, photocatalytic and antibacterial activities of ZnO nanostructures by the influence of doping were also studied. The exciton absorption of ZnO spectrum observed at 370 nm is being blue shifted to 364 nm in doped ZnO confirms the increase in incorporation of Sn and F. As the doping levels of F and Sn are increased, the size of the nanoparticles decreases. This can be observed in the transmission electron microscopic images and XRD results. ZnO is showing the presence of spherical nanoparticles whereas doped samples showing nanosheets structures. The surface morphology of the prepared samples was once again confirmed with SEM pictures. The time-dependent photo-catalytic activities of pure and doped samples of ZnO were studied separately under irradiation of UV-visible and visible light by degradation of methylene blue. The antimicrobial and photocatalytic activities of the prepared samples increased with the increasing doping level of Sn and F. Especially, the nanomaterial was noted with better antimicrobial activity against Staphylococus aureaus and Escherichia coli respectively. This study showed the tuning capabilities by doping level of tin and flourine in ZnO nanostructures.


Assuntos
Nanoestruturas/química , Óxido de Zinco/química , Antibacterianos/química , Antibacterianos/farmacologia , Catálise , Escherichia coli/efeitos dos fármacos , Ferro/química , Luz , Azul de Metileno/química , Nanoestruturas/toxicidade , Fotólise , Staphylococcus aureus/efeitos dos fármacos , Estanho/química , Raios Ultravioleta
15.
Chemosphere ; 258: 127307, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32554007

RESUMO

This study presents a new approach for the investigation of tributyltin (TBT) behaviour and fate in the marine environment. The approach is based on a simultaneous analysis of butyltins (BuTs) and total Sn in sediments, thus enabling an assessment of long-term persistence and historical input of TBT. The study also presents first evaluation of the extent to which the TBT-antifouling paints contribute to the contamination of coastal environments with inorganic Sn; it was demonstrated that the inorganic Sn in the investigated areas primarily originates from TBT degradation. The study was conducted by analyzing BuTs and total Sn in sediments from 34 locations along the Croatian Adriatic coast. The results revealed that 85% of the locations were contaminated with both BuTs and inorganic Sn. The share of Æ©BuTs/total Sn was low (<10%) even in sediments with low TBT degradation efficiency (TBT/Æ©BuTs >40%), demonstrating that only small portion of TBT introduced into the water column reached the sediment before being degraded. This means that recent TBT input into the marine environment may be at least 10 times higher than the amount estimated if only BuTs levels in sediments are considered. It was also demonstrated that TBT concentration in sediments with TOC <1% is not a good indicator of the overall pollution level, even if TBT/TOC approach is used in pollution assessment. Finally, in situ investigation showed that resuspension of contaminated sediments leads to significant release of MBT and DBT into the water column, whereas TBT mainly remains in sediment.


Assuntos
Monitoramento Ambiental , Compostos Orgânicos de Estanho/análise , Poluentes Químicos da Água/análise , Sedimentos Geológicos/análise , Pintura , Água do Mar/análise , Estanho/análise , Compostos de Trialquitina
16.
Acad Radiol ; 27(5): 644-650, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31471205

RESUMO

RATIONALE AND OBJECTIVES: To determine the value of chest CT with tin filtration applying a dose equivalent to chest x-ray for the assessment of the Haller index for evaluation of pectus excavatum. MATERIALS AND METHODS: Two hundred seventy-two patients from a prospective single center study were included and underwent a clinical standard dose chest CT (effective dose 1.8 ± 0.7 mSv) followed by a low-dose CT (0.13 ± 0.01 mSv) in the same session. Two blinded readers independently evaluated all data sets. Image quality for bony chest wall assessment was noted. Radiologists further assessed (a) transverse thoracic diameter, (b) anteroposterior thoracic diameter, and calculated (c) Haller index by dividing transverse diameter by anteroposterior diameter. The agreement of both readers in standard dose and low-dose CT was assessed using Lin's concordance correlation coefficient (pc). RESULTS: Subjective image quality was lower for low dose compared to standard dose CT images by both readers (p < 0.001). In total, 99% (n = 540) of low-dose CT scans were rated as diagnostic for bony chest wall assessment by both readers. There was a high agreement for assessment of transverse diameter, anteroposterior diameter and Haller index comparing both readers in standard dose and low-dose CT with pc values indicating substantial agreement (i.e., 0.95> and ≤0.99) in 12/18 (67%) and almost perfect agreement (i.e., >0.99) in 6/18 (33%). CONCLUSION: Our study suggests that low-dose CT with tin filtration applying a radiation dose equivalent to a plain chest X-ray is excellent for assessing the Haller index.


Assuntos
Tórax em Funil , Estanho , Tórax em Funil/diagnóstico por imagem , Humanos , Estudos Prospectivos , Doses de Radiação , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X , Raios X
17.
Chemosphere ; 243: 125284, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31759210

RESUMO

In order to recognize organic contaminants responsible for ecological stresses from intensive shipping traffic and dockyard works, this study aimed at characterizing the sediment contamination of a large industrialized port located in Hainan Island, China. Surface sediment samples were collected from 17 stations including the main docks, the dockyards and the major industrial wastewater outlets. Organotin compounds, the pesticide DDT (bis(chlorophenyl)trichloroethane) and its metabolites and polycyclic aromatic compounds were identified as main pollutant groups by GC/MS applying a non-target screening approach. The pesticide DDT and its metabolites were found in the same samples as the organotin derivatives pointing to similar emission sources. The concurrent presence of these compounds in the dockyard samples suggests a combined usage of organotin compounds and DDT as active ingredients in antifouling paints in Yangpu. As highly specific molecular indicators for dockyard activities, butyltin and phenyltin compounds were identified. Noteworthy, also tributylmethyltin and triphenylmethyltin were detected, likely resulting from microbial assisted biomethylation of synthetic organotin compounds in the sediments. The concentrations of PAHs, DDX and TBT in sediments from dockyards exceeded global sediment quality guidelines and the toxicity thresholds, and potentially have adverse biological effects on marine organisms.


Assuntos
Diclorodifenil Dicloroetileno/análise , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , China , Sedimentos Geológicos , Desenvolvimento Industrial , Compostos Orgânicos de Estanho/análise , Navios , Estanho/análise
18.
J Trace Elem Med Biol ; 50: 658-663, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29954652

RESUMO

The objective of the present study was to assess the level of aluminium and toxic metals in hair of workers occupationally exposed to aluminium. 124 employees of the aluminium plant working in the hydrometallurgical (n = 43) and sintering units (n = 41), as well as 40 occupationally nonexposed controls were examined. Hair aluminium (Al), arsenic (As), beryllium (Be), cadmium (Cd), mercury (Hg), nickel (Ni), lead (Pb), and tin (Sn) content was assessed using inductively-coupled plasma mass spectrometry. The obtained data demonstrate that aluminium plant workers had significantly higher levels of hair Al (28.8 (15.4-58.6) vs 7.8 (4.3-14.2) µg/g, p < 0.001), Cd (0.053 (0.032 - 0.095) vs 0.025 (0.014 - 0.043) µg/g, p < 0.001) and Pb (0.672 (0.299-1.310) vs 0.322 (0.170 - 0.609) µg/g, p = 0.012) than the controls, respectively. Further analysis demonstrated that persons involved in different technological processes were characterized by distinct hair metal profiles. Hair Al, Be, Cd, Ni, Pb, and Sn levels in men working in the sintering unit of the aluminium plant exceeded the respective control values. In turn, workers of the hydrometallurgical unit were characterized by more than 2-fold higher levels of Al and Cd in hair as compared to the controls. The results of the present study demonstrate that workers of the aluminium plant are characterized by increased risk of Al as well as As, Cd, Pb, and Sn exposure.


Assuntos
Alumínio/análise , Cabelo/química , Espectrometria de Massas/métodos , Adulto , Arsênio/análise , Berílio/análise , Cádmio/análise , Feminino , Humanos , Chumbo/análise , Masculino , Mercúrio/análise , Pessoa de Meia-Idade , Níquel/análise , Estanho/análise
19.
Anal Chim Acta ; 1024: 65-72, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-29776548

RESUMO

In this study we designed an ultrasensitive electrochemical immunosensor for RACK 1 detection using 11-cyanoundecyltrimethoxysilane (11-CUTMS) as a immobilization matrix to immobilize biorecognition element. The used silane agent (11-CUTMS) provides a favorable platform for efficient loading of anti-RACK 1 antibody. The effective loading of the biorecognition element on the 11-CUTMS matrix was monitored by scanning electron microscopy (SEM), atomic force microscopy (AFM) images and fourier transform infrared spectroscopy (FTIR) spectra. The electrochemical characterization of the immunosensor was performed by using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques. Moreover, biorecognition interaction between anti-RACK1 antibodies and RACK1 antigens was monitored by using single frequency technique (SFI). The operating conditions, calibration curves obtained during optimization of experiments and reproducibility of the proposed impedimetric RACK1 biosensor are also investigated and discussed. The electrochemical immunosensor illustrated a sensitive response to RACK 1 antigen with detection limit of 10.8 fg/mL and in the linear range of 0.036-2.278 pg/mL (R2 = 0.999). Owing to high specificity, good reproducibility, long stability and reusability, the fabricated immunosensor will provide a sensitive, selective approach to RACK 1 detection. Furthermore, the practical applicability in human serum samples were investigated with a satisfactory result.


Assuntos
Biomarcadores Tumorais/sangue , Técnicas Biossensoriais , Técnicas Eletroquímicas , Proteínas de Neoplasias/sangue , Receptores de Quinase C Ativada/sangue , Anticorpos Imobilizados/química , Biomarcadores Tumorais/química , Técnicas Biossensoriais/economia , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/economia , Técnicas Eletroquímicas/métodos , Eletrodos , Humanos , Índio/química , Limite de Detecção , Proteínas de Neoplasias/química , Receptores de Quinase C Ativada/química , Reprodutibilidade dos Testes , Silanos/química , Estanho/química
20.
Electrophoresis ; 39(12): 1460-1465, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29543983

RESUMO

This work presents a simple, low-cost method to fabricate semi-circular channels using solder paste, which can amalgamate the cooper surface to form a half-cylinder mold using the surface tension of Sn-Pd alloy (the main component in solder paste). This technique enables semi-circular channels to be manufactured with different dimensions. These semi-circular channels will then be integrated with a polymethylmethacrylate frame and machine screws to create miniaturized, portable microfluidic valves for sequential liquid delivery and particle synthesis. This approach avoids complicated fabrication processes and expensive facilities and thus has the potential to be a useful tool for lab-on-a-chip applications.


Assuntos
Microfluídica , Ligas/química , Desenho de Equipamento/instrumentação , Dispositivos Lab-On-A-Chip , Paládio/química , Tensão Superficial , Estanho/química
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