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1.
J Trace Elem Med Biol ; 83: 127396, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38242005

RESUMO

BACKGROUND: Despite the recognized importance, the determination of halogens in Antarctic seaweeds remains understudied. Limited research exists due to challenges associated with sample preparation, and reliable analytical techniques for this type of analysis. Therefore, further investigations are necessary to bridge this knowledge gap and gain a comprehensive understanding of halogen metabolism in Antarctic seaweeds. METHODS: In this study, seaweeds from the coast of the Antarctic continent were characterized concerning the total content of halogens and their species. For this purpose, different sample preparation methods, based on extraction and combustion, combining highly selective and sensitive chromatographic and spectrometric multi-technique approaches were used. RESULTS: By using optimized methods, it was possible to determine total halogens content, the distribution of bromine and iodine in different classes of species (lipids, water-soluble, proteins, carbohydrates, and residue), as well as the identification of iodinated amino acids (MIT and DIT) in ten brown and red seaweeds. Bromate and iodate were not detected in the samples, which presented only bromide and iodide species in their composition. Additionally, unknown bromine and iodine species were observed in different extracts evaluated. Furthermore, 25 halogenated polyphenols were identified in seaweeds, of which only four were already reported in the literature. CONCLUSION: The results obtained in this study comprise unprecedented data in the literature on species of halogens present in seaweeds from the Antarctic environment.


Assuntos
Iodo , Alga Marinha , Halogênios , Bromo/análise , Regiões Antárticas , Iodo/análise , Alga Marinha/química
2.
Food Chem Toxicol ; 183: 114306, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38052406

RESUMO

This study aims to analyse the risk to consumers given the presence of heavy metals and bromine in honey from different countries. A probabilistic approach was applied to assess carcinogenic risk. Concerning exposure, Al in Spain (3.3E-04 mg/kgBw/day), B in Dominican Republic and Mexico (2E-04 mg/kgBw/day in both cases) and Fe in Mexico and Mozambique had the highest values (5E-05 and 4.8E-05 mg/kgBw/day). In risk characterisation, the values were less than 1 for hazard index (HI), meaning that the consumption of honey represents a low level of concern for non-genotoxic effects. A combination of margin of exposure and probability of exceedance results that exposure to Pb pose no threat. The probability of suffering cancer for Br, Cd, Ni and Pb was lower than 1.0E-06 and, therefore, considered safe. However, the risk at the 95th percentile of Br in Dominican Republic was 1.18E-04 in adults and 2.45E-04 in children, exceeding 1.0E-04, and therefore, considered intolerable. Finally, the sensitivity analysis indicated that the most influential factor in the HI was the consumption in adults and the concentration of Ni in children, whereas for cancer risk, were the concentrations of Ni, Cd, Br and Pb, in both cases.


Assuntos
Mel , Metais Pesados , Neoplasias , Poluentes do Solo , Criança , Adulto , Humanos , Bromo/análise , Mel/análise , República Dominicana , México , Moçambique , Espanha , Cádmio/análise , Chumbo/análise , Medição de Risco , Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Metais Pesados/análise , Poluentes do Solo/análise , China
3.
Se Pu ; 40(6): 584-589, 2022 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-35616204

RESUMO

Ship ballast water can control the roll, trim, and draft of the ship, and thus ensuring the balance and stability of the ship in the course of sailing, and playing a vital role in the safe navigation of ships. The annual discharge of ship ballast water is very large in China. About three to five billion cubic meters of ship ballast water is discharged into offshore or inland waters every year. This water contains plankton, pathogens, and their larvae or spores. If not be handled appropriately, this will have a serious impact on the ecological environment of the discharge waters. Ballast water is usually treated by electrolysis before being discharged. Sodium hypochlorite can be generated, which can kill microorganisms; however, the by-products trihalomethanes (THMs) are cytotoxic and biotoxic. Studies have shown that THMs may cause fetal growth retardation, spontaneous abortion, or death. The concentration of THMs in drinking water is closely related to the risk of bladder cancer death. Hence, it is important to establish a method for the determination of THMs in ship ballast water. The four kinds of THMs are chloroform, dichlorobromomethane, chlorodibromomethane, and tribromomethane. At present, ship ballast water is mostly analyzed by gas chromatography (GC) using an electron capture detector (ECD) or by gas chromatography-mass spectrometry (GC-MS). Given the low boiling point of THMs, headspace injection and purge-and-trap can be used. Gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI-MS), was adopted. NCI is a soft ionization technique that shows special response to compounds bearing electronegative elements or groups. THMs contain electronegative chlorine atoms and bromine atoms. Therefore, NCI is a good choice for their analysis. The samples were processed by the headspace injection technique. The NaCl content in 10 mL sample was optimized in headspace injection. The results showed that 3.0 g NaCl was the most suitable dosage. The analytes were separated on a DB-5MS UI capillary-column (30 m×0.25 mm×1.0 µm). The target compounds were quantified by using the external standard method in selected ion monitoring (SIM) mode. The four THMs were not only well separated but also showed a high response at 0.2 µg/L. The four THMs showed good linear relationships in the range of 0.2-50 µg/L, with correlation coefficients≥0.995. The limits of quantification (LOQs, S/N=10) were 0.1-0.2 µg/L, and the average recoveries of the four THMs were 90.3%-106.8% at the three spike levels of 0.2, 0.5, and 2.0 µg/L. The relative standard deviations were 1.4%-6.2%. The LOQs of the THMs in the GB/T 5750.8-2006 Standard Test Method of Drinking Water Organic Matter Index are 0.3-6.0 µg/L. It can be seen that the LOQs of the THMs are greatly reduced in this study. The proposed method is accurate, stable, and reliable, and it can be used for monitoring the four THMs in ship ballast water. The method was applied for the detection of 36 ship ballast water samples. In all cases, the detection rates of tribromomethane, chlorodibromomethane, dichlorobromomethane, and chloroform were 83.3%, 69.4%, 22.2%, and 19.4%, respectively. The detection values of tribromomethane, chlorodibromomethane, dichlorobromomethane, and chloroform were 34.25-221.5 µg/L, 3.52-41.87 µg/L, 1.52-8.56 µg/L, and 0.02-5.46 µg/L, respectively. Based on the analysis of several ship ballast water samples (electrolytic water), it was concluded that the greater the number of bromine atoms in the THMs, the higher are the detection rate and detection value in ship ballast water. Compared to chloroform, tribromomethane is more harmful to living beings. China has acceded to the International Convention on Ship Ballast Water and Sediment Control and Management. There is an urgent need to establish analysis methods with high sensitivity, good stability, and high accuracy in addition to determining standards and regulations for ship ballast water.


Assuntos
Água Potável , Navios , Bromo/análise , Clorofórmio/análise , Água Potável/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cloreto de Sódio/análise , Trialometanos/análise , Trialometanos/toxicidade
4.
J Chromatogr A ; 1634: 461715, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33221653

RESUMO

A compound-specific chlorine/bromine isotope analysis (Cl-/Br-CSIA) method was developed using gas chromatography-quadrupole mass spectrometry for polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), which are toxic to human health and are frequently detected in various abiotic and biotic media. For PCB congeners, the molecular ion method for a concentration of 0.5-10.0 ppm, a dwell time of 20-100 ms, a relative EM voltage of 200 V, an electric current of 34 µA, and an ionization energy of 70 eV was determined as the most suitable scheme, which obtained standard deviations (SDs) of chlorine isotope ratios ranging from 0.00008 to 0.00068. As for the PBDE congeners, the lowest SDs, ranging from 0.00050 to 0.00172, were determined using the top four ion method with a concentration of 5-10 ppm and a dwell time of 20-50 ms. Both the chlorine and bromine isotope ratios showed strong concentration dependencies. Therefore, external standardization or detecting chlorine and bromine isotope ratios at a uniform concentration level is necessary to eliminate the concentration effect. In addition, 13C-correction is critical to remove interference from carbon isotopes. This newly developed Cl-/Br-CSIA method successfully determined the chlorine/bromine isotope ratios of PCBs/PBDEs in technical mixtures and traced the chlorine/bromine isotope ratio variations of PCBs/PBDEs in photodegradation experiments, thereby suggesting that it is a promising tool for assessing the sources and transformation processes of PCBs and PDBEs in the environment.


Assuntos
Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas , Éteres Difenil Halogenados/análise , Bifenilos Policlorados/análise , Bromo/análise , Bromo/química , Cloro/análise , Cloro/química , Poluentes Ambientais/química , Éteres Difenil Halogenados/química , Humanos , Isótopos/análise , Isótopos/química , Bifenil Polibromatos/análise , Bifenilos Policlorados/química
5.
Environ Monit Assess ; 192(1): 36, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31828539

RESUMO

The bromide concentration in water source (WS) of Yancheng City in China increased unexpectedly due to industrial discharge and saltwater intrusion, which leads to the formation of trihalomethane (THMs) in finished water of water treatment plants (WTP), especially brominated THMs. In Yancheng City, drinking water is supplied by WTP1 and WTP2, primarily sourced by WS1 and WS2, respectively. In this paper, the seasonal variations of bromide in WS1 and WS2 and THMs species in WTP1 and WTP2 were analyzed and compared. The effects of bromide in WS on THMs formation in finished water of WTP in terms of bromine substitution factor (BSF) were simulated by statistical linear model. Although the THMs concentrations in WTP1 were approximate to that in WTP2, the brominated THMs concentrations in WTP1 were higher than that in WTP2 due to higher bromide concentration in WS1 than WS2. The cancer risk analysis indicated that THMs' species of DBCM is the dominant THMs for WTP1 as well as WTP2, which can provide more information for WTPs with higher bromide concentration in water source.


Assuntos
Brometos/análise , Exposição Dietética/estatística & dados numéricos , Água Potável/química , Poluentes Químicos da Água/análise , Poluição da Água/estatística & dados numéricos , Bromo/análise , China , Desinfecção , Água Potável/análise , Monitoramento Ambiental , Halogenação , Estações do Ano , Trialometanos/análise , Purificação da Água , Abastecimento de Água
6.
Ecotoxicol Environ Saf ; 153: 142-150, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29425845

RESUMO

Heavy metals and bromine (Br) derived from organic and industrialized fertilizers can be absorbed, transported and accumulated into parts of plants ingested by humans. This study aimed to evaluate in an experiment conducted under no-tillage for 10 years, totaling 14 applications of pig slurry manure (PS), pig deep-litter (PL), dairy slurry (DS) and mineral fertilizer (MF), the heavy metal and Br contents in soil and in whether the grains produced by corn (Zea mays L.) and wheat (Triticum aestivum L.) under these conditions could result in risk to human health. The total contents of As, Cd, Pb, Cr, Ni, Cu, Zn and Br were analyzed in samples of fertilizers, waste, soil, shoots and grains of corn and wheat. Afterwards, enrichment factor (EF), accumulation factor (AF), health risk index (HRI), target hazard quotient (THQ) and target cancer risk (TCR) were determined. Mineral fertilizer exhibited the highest As and Cr content, while the highest levels of Cu and Zn were found in animal waste. The contents of As, Cd, Cr, Cu, Ni, Pb and Zn in soil were below the limits established by environmental regulatory agencies. However, a significant enrichment factor was found for Cu in soil with a history of PL application. Furthermore, high Zn contents were found in shoots and grains of corn and wheat, especially when the plants were grown in soil with organic waste application. Applications of organic waste and mineral fertilizer provided high HRI and THQ for Br and Zn, posing risks to human health. The intake of corn and wheat fertilized with pig slurry manure, swine deep bed, liquid cattle manure and industrialized mineral fertilizer did not present TCR.


Assuntos
Bromo/análise , Produtos Agrícolas/química , Monitoramento Ambiental/métodos , Fertilizantes/análise , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Animais , Brasil , Bovinos , Humanos , Esterco/análise , Minerais/análise , Medição de Risco , Suínos
7.
Environ Pollut ; 227: 139-145, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28458244

RESUMO

Samples of microplastic (n = 924) from two beaches in south west England have been analysed by field-portable-x-ray fluorescence (FP-XRF) spectrometry, configured in a low-density mode and with a small-spot facility, for the heavy metals, Cd and Pb, and the halogen, Br. Primary plastics in the form of pre-production pellets were the principal type of microplastic (>70%) on both beaches, with secondary, irregularly-shaped fragments representing the remainder of samples. Cadmium and Pb were detected in 6.9% and 7.5% of all microplastics, respectively, with concentrations of either metal that exceeded 103 µg g-1 usually encountered in red and yellow pellets or fragments. Respective correlations of Cd and Pb with Se and Cr were attributed to the presence of the coloured, inorganic pigments, cadmium sulphoselenide and lead chromate. Bromine, detected in 10.4% of microplastics and up to concentrations of about 13,000 µg g-1, was mainly encountered in neutrally-coloured pellets. Its strong correlation with Sb, whose oxides are effective fire suppressant synergists, suggests the presence of a variety of brominated flame retardants arising from the recycling of plastics originally used in casings for heat-generating electrical equipment. The maximum bioaccessible concentrations of Cd and Pb, evaluated using a physiological extraction based on the chemical characteristics of the proventriculus-gizzard of the northern fulmar, were about 50 µg g-1 and 8 µg g-1, respectively. These concentrations exceed those estimated for the diet of local seabirds by factors of about 50 and 4, respectively.


Assuntos
Bromo/análise , Cádmio/análise , Monitoramento Ambiental , Chumbo/análise , Plásticos/análise , Inglaterra , Retardadores de Chama/análise , Metais Pesados/análise , Reciclagem
8.
Talanta ; 152: 341-52, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26992530

RESUMO

Tea is one of the most common and popular beverages spanning vast array of cultures all over the world. The main nutritional benefits of drinking tea are its anti-oxidant properties, presumed protection against certain cancers, inhibition of inflammation and possible protective effects against diabetes. Laser induced breakdown spectrometer (LIBS) was assembled as a powerful tool for qualitative and quantitative analysis of various brands of tea samples using 266 nm pulsed UV laser. LIBS spectra for six brands of tea samples in the wavelength range of 200-900 nm was recorded and all elements present in our tea samples were identified. The major toxic elements detected in several brands of tea samples were bromine, chromium and minerals like iron, calcium, potassium and silicon. The spectral assignment was conducted prior to the determination of concentration of each element. For quantitative analysis, calibration curves were drawn for each element using standard samples prepared in known concentration in the tea matrix. The plasma parameters (electron temperature and electron density) were also determined prior to the tea samples spectroscopic analysis. The concentration of iron, chromium, potassium, bromine, copper, silicon and calcium detected in all tea samples was between 378-656, 96-124, 1421-6785, 99-1476, 17-36, 2-11 and 92-130 mg L(-1) respectively. The limits of detection estimated for Fe, Cr, K, Br, Cu, Si, Ca in tea samples were 22, 12, 14, 11, 6, 1 and 12 mg L(-1) respectively. To further confirm the accuracy of our LIBS results, we determined the concentration of each element present in tea samples by using standard analytical technique like ICP-MS. The concentrations detected with our LIBS system are in excellent agreement with ICP-MS results. The system assembled for spectral analysis in this work could be highly applicable for testing the quality and purity of food and also pharmaceuticals products.


Assuntos
Lasers , Espectrometria de Massas/métodos , Chá/química , Raios Ultravioleta , Métodos Analíticos de Preparação de Amostras , Bromo/análise , Bromo/isolamento & purificação , Cromo/análise , Cromo/isolamento & purificação , Ferro/análise , Ferro/química , Potássio/análise , Potássio/isolamento & purificação
9.
J Environ Sci Health B ; 51(6): 358-65, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26950676

RESUMO

Laser induced breakdown spectroscopy (LIBS) was applied for the detection of carcinogenic elements like bromine in four representative brands of loaf bread samples and the measured bromine concentrations were 352, 157, 451, and 311 ppm, using Br I (827.2 nm) atomic transition line as the finger print atomic transition. Our LIBS system is equipped with a pulsed laser of wavelength 266 nm with energy 25 mJ pulse(-1), 8 ns pulse duration, 20 Hz repetition rate, and a gated ICCD camera. The LIBS system was calibrated with the standards of known concentrations in the sample (bread) matrix and such plot is linear in 20-500 ppm range. The capability of our system in terms of limit of detection and relative accuracy with respect to the standard inductively coupled plasma mass spectrometry (ICPMS) technique was evaluated and these values were 5.09 ppm and 0.01-0.05, respectively, which ensures the applicability of our system for Br trace level detection, and LIBS results are in excellent agreement with that of ICPMS results.


Assuntos
Pão/análise , Bromo/análise , Carcinógenos/análise , Análise de Alimentos/métodos , Análise Espectral/métodos , Calibragem , Lasers , Luz , Espectrometria de Massas/métodos , Análise Espectral/instrumentação , Raios Ultravioleta
10.
Artigo em Russo | MEDLINE | ID: mdl-28091491

RESUMO

Irritable bowel syndrome (IBS) is a pathological condition characterized by heterogeneous etiology, pathogenesis, and clinical symptoms. These characteristics dictate the necessity of prescribing multiple medications for the treatment of IBS. Such compulsory polypharmacy inadvertently enhances the risk of adverse reactions to the treatment, increases its cost, and impairs compliance on the part of the patients. The objective of the present study was to evaluate the effectiveness of the administration of the clorine-bromine brine with the use of sinusoidal modulated current electrophoresis (SMC-phoresis) for the treatment of different forms of IBS. THE PATIENTS AND METHODS: We examined and treated 80 patients with different forms of IBS. The patients were divided into two equal groups comprised of 40 patients each. The patients of the study group were treated with the use of SMС-phoresis of the bromine-chlorine brine based at the «Varzi-yatchi¼ spa and health resort (the Udmurt Republic) making use of the sparing or stimulating techniques depending on the type of IBS. Each therapeutic course consisted of 10-12 sessions. The patients in the group of comparison received the standard pharmaceutical treatment for IBS (myotropic anti-spasmodics and lactulose). The emphasis was laid on the evaluation of dynamics of the intestinal motor function in different variants of IBS with the use of the EGS-4M apparatus based on the GSRS questionnaire (Gastrointestinal Symptom Rating Scale). Special attention was given to the interpretation of the main gastrointestinal syndromes and the evaluation of the quality of life of the patients in the course of the treatment and after its completion. RESULTS: Тhe main symptoms of IBS after a course of SMC-phoresis with the natural brine were significantly less pronounced compared to those in the patients managed by means of standard pharmacotherapy. Positive dynamics in the clinical picture of the disease had beneficial influence on the quality of life of the patients which approached that of the healthy subjects in the group of comparison. The results of colonography suggested the presence of various types of disturbances of motor function of the intestines. SMC-phoresis of the natural chlorine-bromine brine had a positive influence on dyskinesia associated with diarrhea and constipation associated with IBS, while the effect of the standard pharmaceutical treatment was unidirectional and significantly inferior to it in terms of efficiency. CONCLUSION: The use of complementary therapy can provide a better clinical outcome of IBS and to a greater extent improve the quality of life of the patients presenting with various forms of this pathology.


Assuntos
Síndrome do Intestino Irritável/terapia , Modalidades de Fisioterapia , Sais/uso terapêutico , Administração Cutânea , Adulto , Bromo/administração & dosagem , Bromo/análise , Bromo/uso terapêutico , Cloro/administração & dosagem , Cloro/análise , Cloro/uso terapêutico , Eletroforese , Feminino , Estâncias para Tratamento de Saúde , Humanos , Síndrome do Intestino Irritável/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Sais/administração & dosagem , Sais/química
11.
Rapid Commun Mass Spectrom ; 29(13): 1196-204, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26395784

RESUMO

RATIONALE: We describe the analytical characterization of the designer drug bk-2C-B, a cathinone derivative, contained in a seized tablet, in the absence of an analytical standard. METHODS: The analytical techniques employed include gas chromatography/mass spectrometry (GC/MS), without and with derivatization with 2,2,2-trichloroethyl chloroformate, liquid chromatography/high-resolution-MS (LC/HRMS) with an Orbitrap® analyzer, and nuclear magnetic resonance (NMR). LC/HRMS measurements consisted of accurate mass measurements of MH(+) ionic species under full scan conditions; comparison of experimental and calculated MH(+) isotopic patterns; examination of the isotopic fine structure (IFS) of the M+1, M+2, M+3 isotopic peaks relative to the monoisotopic M+0 peak; study of MH(+) collision-induced dissociation (CID) product ions obtained in fragmentation experiments. RESULTS: GC/MS analysis gave highly informative EI mass spectra, particularly after the derivatization of bk-2C-B with 2,2,2-trichloroethyl chloroformate. The application of LC/HRMS, allowing for accurate mass measurements at 100,000 resolving power, greatly enhanced analytical capabilities in structural characterization of this new designer drug. HRMS allowed us to obtain the accurate mass measurements of bk-2C-B MH(+) ionic species, with a mass accuracy of 2.19 ppm; fully superimposable experimental and calculated MH(+) isotopic patterns, with RIA1 and RIA2 values <4%; the IFS of the M+1, M+2, M+3 isotopic peaks relative to the monoisotopic M+0 peak completely in accordance with theoretical values. These findings enabled us to obtain the elemental composition formula of the seized drug. Furthermore, characteristic MH(+) CID product ions enabled the characterization of the bk-2C-B molecular structure. The presence of (79)Br and (81)Br isotopes in the substance molecule produced a characteristic isotopic pattern in most MS spectra. Lastly, NMR spectra allowed us to obtain useful information about the position of substituents in the designer drug. CONCLUSIONS: The combination of all the analytical techniques employed allowed the characterization of the seized psychoactive substance, in spite of the lack of a reference standard.


Assuntos
Acetofenonas/análise , Drogas Desenhadas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Bromo/análise , Cromatografia Líquida/métodos , Isótopos/análise , Fosgênio/análogos & derivados , Fosgênio/química , Comprimidos/análise
12.
Environ Sci Technol ; 49(10): 5921-9, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25894116

RESUMO

Wildfire occurrence and intensity are increasing worldwide causing severe disturbances to forest watersheds used for potable water supply. The effects of wildfire on drinking water quality are not well understood, especially in terms of terrestrial dissolved organic matter (DOM) and DOM-associated formation of disinfection byproducts (DBP). As the forest floor layer is a major source of terrestrial DOM, we investigated characteristics and DBP formation of water extractable organic matter (WEOM) from the 0-5 cm depth of nonburned detritus (control) and burned detritus with black ash (moderate severity) and white ash (high severity) associated with the 2013 Rim Fire in California. Spectroscopic results suggested that the aromaticity of WEOM followed white ash > control > black ash and fluorescence region II (excitation 220-250 nm; emission 330-380 nm) of the emission-excitation-matrix was identified as a potential burn severity indicator. Compared to the control, WEOM from white and black ashes had lower reactivity in forming trihalomethanes (55%-of-control) and haloacetic acids (67%-of-control), but higher reactivity in forming the more carcinogenic haloacetonitrile after chlorination (244%-of-control) and N-nitrosodimethylamine after chloramination (229%-of-control). There was no change in reactivity for chloral hydrate formation, while WEOM from black ash showed a higher reactivity for haloketone formation (150%-of-control). Because wildfire consumed a large portion of organic matter from the detritus layer, there was lower water extractable organic carbon (27%-of-control) and organic nitrogen (19%-of-control) yields in ashes. Consequently, the wildfire caused an overall reduction in water extractable terrestrial DBP precursor yield from detritus materials.


Assuntos
Desinfecção , Incêndios , Florestas , Bromo/análise , California , Carbono/análise , Dimetilnitrosamina/análise , Fluorescência , Halogenação , Nitrogênio/análise , Trialometanos/análise , Qualidade da Água
13.
Talanta ; 139: 117-22, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25882416

RESUMO

The polybrominated flame retardants and organotin compounds were screened in terms of bromine and tin content using laser ablation inductively coupled plasma mass spectrometry in plastics. The calibration standards were prepared using the fused-disk technique, and all samples were investigated under optimal conditions. Using a central composite experimental design, laser parameters, laser energy, pulse rate, scan rate and spot size were identified. The detection limits of the method were 1000 mgkg(-1) and 1600 mgkg(-1) for bromide and tin, whereas the relative standard deviation (%) values of the analysis were 9% and 6% (n=3) for ERM EC681k with 770 ± 70 mgkg(-1) Br and 86 ± 6 mgkg(-1) Sn respectively, and 106-115% of Br and 102-104% of Sn were observed for the tetrabromobisphenol A and butyltin trichloride spike plastics, respectively.


Assuntos
Bromo/análise , Retardadores de Chama/análise , Terapia a Laser , Espectrometria de Massas/métodos , Plásticos/química , Compostos de Estanho/análise , Calibragem
14.
Biol Trace Elem Res ; 164(1): 25-35, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25519178

RESUMO

In order to clarify the differences between Ag, Br, Ca, Co, Cr, Fe, Hg, K, Mg, Mn, Na, Rb, Sb, Sc, Se, and Zn contents in hyperplastic (patients with benign prostate hyperplasia (BPH), n = 32) and nonhyperplastic (control group of healthy male inhabitants, n = 32) prostates, an instrumental neutron activation analysis was performed. Mean values (M ± SΕΜ) for mass fraction (mg/kg, dry mass basis) of chemical elements in glands of patients with BPH were the following: Ag, 0.0346 ± 0.0060; Br, 30.4 ± 3.6; Ca, 2030 ± 165; Co, 0.0716 ± 0.0097; Cr, 1.073 ± 0.119; Fe, 130.0 ± 7.9; Hg, 0.232 ± 0.030; K, 14,470 ± 740; Mg, 1200 ± 80; Mn, 1.19 ± 0.09; Na, 11,610 ± 870; Rb, 14.7 ± 0.8; Sb, 0.163 ± 0.025; Sc, 0.0257 ± 0.0040; Se, 1.243 ± 0.079; and Zn, 1235 ± 92. It was observed that in BPH tissue, the mass fraction of Co (p < 0.015), Cr (p < 0.0002), Hg (p < 0.000007), K (p < 0.001), Rb (p < 0.048), Sb (p < 0.0001), and Se (p < 0.000001) were significantly higher than in controls. In the sixth to eighth decades, the mass fractions of almost all chemical elements in hyperplastic prostates did not depend from age. Our finding of correlation between pairs of prostatic chemical element mass fractions indicates that there is a great disturbance of prostatic chemical element relationships with a benign hyperplastic transformation. The results apparently confirm the disturbed homeostasis of Zn and Se and some other chemical elements in the etiology of BPH.


Assuntos
Análise de Ativação de Nêutrons/métodos , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Bromo/análise , Cálcio/análise , Cromo/análise , Cobalto/análise , Humanos , Ferro/análise , Magnésio/análise , Masculino , Mercúrio/análise , Metais Pesados/análise , Pessoa de Meia-Idade , Potássio/análise , Selênio/análise , Prata/análise , Sódio/análise , Zinco/análise
15.
Biol Trace Elem Res ; 157(3): 195-204, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24435825

RESUMO

The variation with age of the Br, Fe, Rb, Sr, and Zn mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0-30 years was investigated by an energy-dispersive X-ray fluorescence and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet-mass basis) of these trace elements in pre-puberty were: Br-10.5 ± 1.3, Fe-28.6 ± 4.1, Rb-3.05 ± 0.27, Sr-0.42 ± 0.08, and Zn-32.9 ± 3.2. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Br-5.60 ± 0.57, Fe-19.3 ± 1.6, Rb-3.50 ± 0.28, Sr-0.24 ± 0.03, and Zn-113 ± 10. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium, and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. A significant positive correlation between the prostatic Zn and percent volume of both glandular epithelium (r = 0.573, p ≤ 0.001) and glandular lumen (r = 0.725, p ≤ 0.001) was found. For the first time, it has been demonstrated that the glandular lumen is a main pool of Zn accumulation, and that the stroma is a main pool of Br and Fe accumulation in the normal human prostate, for the age range 14 to 30 years. It was concluded that the Zn binds tightly within the prostatic fluid because the volume of glandular lumen reflects the volume of prostatic fluid.


Assuntos
Bromo/análise , Ferro/análise , Próstata/anatomia & histologia , Próstata/química , Rubídio/análise , Estrôncio/análise , Zinco/análise , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Masculino , Adulto Jovem
16.
Artigo em Inglês | MEDLINE | ID: mdl-24040839

RESUMO

In order to screen for the presence of a recycled polymer waste stream from waste electric and electronic equipment (WEEE), a market survey was conducted on black plastic food-contact articles (FCA). An analytical method was applied combining X-ray fluorescence spectrometry (XRF) with thermal desorption gas chromatography coupled with mass spectrometry (thermal desorption GC-MS). Firstly, XRF spectrometry was applied to distinguish bromine-positive samples. Secondly, bromine-positive samples were submitted for identification by thermal desorption GC-MS. Generally, the bromine-positive samples contained mainly technical decabromodiphenyl ether (decaBDE). Newer types of BFRs such as tetrabromobisphenol A (TBBPA), tetrabromobisphenol A bis(2,3-dibromopropyl), ether (TBBPA-BDBPE) and decabromodiphenylethane (DBDPE), replacing the polybrominated diphenyleters (PBDEs) and polybrominated diphenyls (PBBs), were also identified. In none of the tested samples were PBBs or hexabromocyclododecane (HBCD) found. Polymer identification was carried out using Fourier-transformed infrared spectroscopy measurement (FTIR) on all samples. The results indicate that polypropylene-polyethylene copolymers (PP-PE) and mainly styrene-based food-contact materials, such as acrylonitrile-butadiene-styrene (ABS) have the highest risk of containing BFRs.


Assuntos
Compostos de Bromo/análise , Utensílios de Alimentação e Culinária , Retardadores de Chama/análise , Embalagem de Alimentos/instrumentação , Resinas Acrílicas/química , Bromo/análise , Butadienos/química , Europa (Continente) , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas , Bifenil Polibromatos/análise , Polietilenos/química , Polímeros/análise , Polipropilenos/química , Poliestirenos/química , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier
17.
J Trace Elem Med Biol ; 27(1): 76-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22796020

RESUMO

The aim of the study was to investigate possible changes in the elemental content of small biological tissue samples (with low weight) during the short period of fixation in formalin. Therefore, the effect of the fixation time (4 h to 6 days) was studied on the elemental content of the tissue. Synchrotron radiation X-ray fluorescent analysis (SRXRF) technique was used for the determination of the elemental concentrations. The levels of Cl, K, Ca, Br, Rb, and Sr in the samples fixed for 4h (and longer) show significant differences in comparison with levels in fresh samples, because these ions have a high mobility and capacity for moving through the cell membrane. The content of Zn, Se, Fe, and Cu in the samples fixed by formalin solution during 4h do not show significant differences compared with fresh samples. The ions of these elements can form complexes with the large protein molecules in the tissue and can hardly be removed from it.


Assuntos
Formaldeído , Miocárdio/química , Síncrotrons , Fixação de Tecidos , Animais , Bromo/análise , Cálcio/análise , Cloro/análise , Fixadores/química , Formaldeído/química , Potássio/análise , Ratos , Ratos Wistar , Rubídio/análise , Espalhamento de Radiação , Espectrometria de Fluorescência , Estrôncio/análise
18.
J Air Waste Manag Assoc ; 61(5): 535-42, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21608493

RESUMO

The production of waste printed circuit boards (WPCBs) has drawn increasing global concern, especially because the high bromine (Br) content (5-15%) places obstacles in the way of simple disposal techniques. Microwave-induced pyrolysis of WPCBs provides a promising way to dispose of these hazardous and resource-filled wastes. The transference rules for Br during microwave-induced pyrolysis have been investigated experimentally. It was found that the microwave energy could be used more efficiently to accelerate the heating rate and improve the final pyrolysis temperature by adding some activated carbon (AC) as microwave absorbents. The high temperature and rapid pyrolysis process promoted the yields of gaseous products and the decomposition of brominated compounds into hydrogen bromide and then benefited the capture of Br and the debromination of byproducts. The application of a calcium carbonate (CaCO3) layer overhead led to over 95% debromination of the liquid products and over 50% capture of the total Br. It can be concluded that the presented method is suitable for the control of Br transference in the recycling of WPCBs. This method can also be extended to the disposal of the electronic scraps.


Assuntos
Bromo/isolamento & purificação , Resíduo Eletrônico , Retardadores de Chama/isolamento & purificação , Eliminação de Resíduos/métodos , Eliminação de Resíduos Líquidos/métodos , Aceleração , Bromo/análise , Bromo/toxicidade , Carbonato de Cálcio/química , Carbono/química , Equipamentos Descartáveis , Equipamentos e Provisões Elétricas , Resíduo Eletrônico/efeitos adversos , Resíduo Eletrônico/análise , Monitoramento Ambiental/normas , Retardadores de Chama/análise , Retardadores de Chama/toxicidade , Resíduos Perigosos/análise , Resíduos Perigosos/prevenção & controle , Humanos , Incineração/normas , Micro-Ondas
19.
J Chromatogr A ; 1216(7): 1059-66, 2009 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-19135207

RESUMO

A new approach using single-drop microextraction (SDME) and gas chromatography-mass spectrometry for the determination of six haloacetic acids (HAAs) in water samples was presented. n-Octanol was used as extractant and derivatization reagent. HAAs were derivatized both simultaneously during the extraction in the solvent microdrop, and after extraction, inside a glass microvial (1.1mm I.D.). Trifluoroacetic anhydride (TFAA) was used as the reaction catalyst. The influence of catalyst amount, derivatization time and temperature on the yield of the in-microvial derivatization was investigated. Derivatization reaction was performed using 1.2microL of TFAA at 100 degrees C for 20min. Extraction was performed using 1.8microL of n-octanol containing TFAA (10%, v/v). Experimental parameters, such as, exposure time, sample pH and extraction temperature were controlled and optimized. Analytical parameters such as linearity, precision and limit of detection were also evaluated. The proposed method was proved to be a suitable analytical procedure for HAAs in water with limits of detection 0.1-1.2microg/L. The relative recoveries range from 82.5 to 97.6% for all the target analytes. Precision values were from 5.1 to 8.5% (as intra-day relative standard deviation, RSD) and 8.8-12.3% (as inter-day RSD).


Assuntos
Acetatos/análise , Bromo/análise , Fracionamento Químico/métodos , Cloro/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Poluição Química da Água/análise , 1-Octanol/química , Água Doce/química , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes/química , Sulfatos/química , Temperatura , Ácido Trifluoracético/química
20.
J Microsc ; 232(1): 27-35, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19017198

RESUMO

The subcellular localization of RNA for understanding transcriptional activity by using RNA precursors, like 5-bromouridine (BrU), generally requires chemical fixation and staining of cells with monoclonal antibody for imaging BrU-containing RNA in individual cells. Although effective for RNA localization, the native chemical composition of diffusible ions and molecules is destroyed in this approach and one cannot study their spatial relationship with RNA localization sites in this sample type. This work presents a novel secondary ion mass spectrometry approach in cryogenically prepared cells, which allows the same cell imaging of RNA (and/or replicating DNA) distribution in relation to intracellular chemical composition. The heat shock treatment of HeLa cells was used as a model system because the transcription of heat shock genes is activated during heat shock while other transcriptional activities of the cell are suppressed. The HeLa cells were heat-shocked for 1 h at 42 degrees C in presence of 100 muM BrU and/or 100 microM IdU (5-iododeoxyuridine). Following the heat shock treatments, the cells were cryogenically prepared with our sandwich freeze-fracture method and freeze-dried prior to secondary ion mass spectrometry analysis. A CAMECA IMS 3f secondary ion mass spectrometry ion microscope (CAMECA, Paris, France) capable of producing elemental (isotopic) distributions with a spatial resolution of 500 nm was used in the study. Secondary ion mass spectrometry analysis of fractured freeze-dried HeLa cells revealed well-preserved intracellular (39)K and (23)Na concentrations in heat-shocked cells. Both DNA replication and RNA distribution (total RNA) were imaged directly in the same cell by secondary ion mass spectrometry imaging of masses (127)I (from IdU) and (81)Br (from BrU), respectively. Surprisingly, the nucleus of heat-shocked cells contained spatially resolved regions with elevated levels of bound calcium (approximately 0.75 mM total calcium instead of 0.50 mM total calcium in the nucleoplasm). These regions spatially correlated with depleted levels of BrU-RNA in (81)Br secondary ion mass spectrometry images. The remainder of intranuclear regions displayed the presence of BrU-RNA with heterogeneous distribution. These observations indicate that calcium in its bound form may play a fundamental role in processes such as transcription and/or processing and storage of RNA. The shape of intranuclear regions with elevated levels of bound calcium resembled the heat shock induced nuclear bodies in HeLa cells. The analysis of cryogenically prepared frozen freeze-dried cells provides an ideal sample type for further understanding of the role of bound calcium in transcription of genes under physiological and pathological conditions.


Assuntos
Cálcio/análise , Replicação do DNA , Células Epiteliais/química , Células Epiteliais/fisiologia , Resposta ao Choque Térmico , RNA/análise , Espectrometria de Massa de Íon Secundário/métodos , Bromo/análise , DNA/análise , Liofilização , Células HeLa , Humanos , Isótopos de Iodo/análise , Isótopos de Potássio/análise , Isótopos de Sódio/análise
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