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1.
Int J Occup Med Environ Health ; 33(6): 757-769, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33051631

RESUMO

Mineral wool is widely used for thermal and sound insulation. The subject of the study is to identify hazards for employees resulting from exposure to mineral wool, when it is used to insulate buildings, and to assess the risk arising from this exposure. When installing mineral wool insulation, respirable mineral fibers, dust, and volatile organic compounds may pose a hazard at workplaces. Based on the results of concentration measurements, it was assessed that the probability of adverse health effects related to the work of insulation installers, resulting from exposure to mineral wool fibers, is low, but for dust associated with exposure, an average health risk was estimated. An additional threat may be the sensitizing effect of substances used as binders and additives improving the utility properties of mineral wool, for example, phenol formaldehyde resins. The paper also contains some information on the labeling of mineral wool; this is very important because the label allows downstream users to recognize mineral wools, the composition and properties of which cause that they are not classified as carcinogens. Int J Occup Med Environ Health. 2020;33(6):757-69.


Assuntos
Compostos de Cálcio/efeitos adversos , Materiais de Construção/efeitos adversos , Exposição Ocupacional/efeitos adversos , Silicatos/efeitos adversos , Compostos de Cálcio/análise , Compostos de Cálcio/normas , Materiais de Construção/análise , Materiais de Construção/normas , Poeira/análise , Humanos , Fibras Minerais/efeitos adversos , Fibras Minerais/análise , Fibras Minerais/normas , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/normas , Rotulagem de Produtos , Medição de Risco , Silicatos/análise , Silicatos/normas , Compostos Orgânicos Voláteis/efeitos adversos , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/normas , Local de Trabalho
2.
Int J Hyg Environ Health ; 229: 113588, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32784067

RESUMO

In Europe, the Construction Products Regulation sets harmonized conditions for the marketing of construction products with the objective of protecting the building users' health. Until now only three European countries have implemented requirements for the assessment of VOC emissions from construction products. Therefore, the European Commission is planning the issue of a delegated act on the communication of VOC emissions from construction products in the form of VOC classes. A key prerequisite for defining the VOC classes is the completion of the EU-LCI list currently being carried out by a group of experts from ten European countries. This paper reports on the development of the VOC class concept, the progress of the EU-LCI harmonization framework and Germany's current efforts to ensure a high level of health protection for building users and avoid dangers from construction product emissions.


Assuntos
Poluentes Atmosféricos/normas , Poluição do Ar em Ambientes Fechados/prevenção & controle , Materiais de Construção/normas , Compostos Orgânicos Voláteis/normas , União Europeia , Risco
3.
Food Chem ; 322: 126743, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283368

RESUMO

Sensory properties are critical characteristics that determine quality and can be evaluated by trained tasting panels. The panels function as multi-sensor measuring instrument and need the use of reference materials (RMs) for training. The homogeneity between units packaged from a batch of RM can be evaluated by gas chromatography coupled to flame ionization detection (GC-FID), using this instrumental technique as an alternative to sensory analysis. For this purpose, the fingerprint methodology is applied, taking into account that the homogeneity assessment will be based on evaluating the similarity between the fingerprints of the fraction of volatile organic compounds acquired from samples representative of the batch. The proposed methodology is applied with good results to evaluate the homogeneity of several RMs for sensory analysis of virgin olive oil samples, using similarity indices, control charts and exploratory analysis of multivariate data to observe the grouping RM and fingerprint regions representative of each defect.


Assuntos
Cromatografia Gasosa/métodos , Azeite de Oliva/normas , Cromatografia Gasosa/normas , Análise por Conglomerados , Azeite de Oliva/química , Óleos de Plantas/química , Análise de Componente Principal , Padrões de Referência , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/normas
4.
Anal Bioanal Chem ; 411(29): 7841-7855, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31748896

RESUMO

Human beings are inevitably exposed to volatile organic compounds (VOCs) of anthropogenic emissions as they are ubiquitous atmospheric pollutants. Smoking is an important exposure route of VOCs for the general population. Health effects induced by VOC exposure raise more concerns as they are identified with carcinogenicity, genotoxicity, neurotoxicity, and reproductive toxicity. trans-3'-Hydroxycotinine (OH-Cot) is a urinary biomarker of smoking, and 8-hydroxy-2'-deoxyguanosine (8-OHDG) is a urinary biomarker of DNA oxidative damage. To develop a method for quantifying VOC exposure levels of the general population and assessing the health risks induced by VOCs from second-hand smoking, an effective, rapid, and high-throughput method for the simultaneous determination of 31 metabolites of VOCs, 8-OHDG, and OH-Cot using solid-phase extraction coupled with UPLC-MS/MS was developed and validated. Method precision and accuracy, extraction recoveries, matrix effects, and storage stabilities of most analytes met the criterion (80-120%). Extraction recoveries increased from 85.1 to 100% after adjustment by isotoped internal standards (ISs). Furthermore, 13C- and 15N-labeled ISs were more effective to reduce the influence of matrix effects on recoveries and precisions than the deuterated analogs (73.0-116% vs. 53.6-140%). This developed method was successfully applied to determine urine samples collected from children. Results showed that N-acetyl-S-(3,4-dihydrobutyl)-L-cysteine, 2,2'-thiodiacetic acid (TGA), and N-acetyl-S-(3-hydroxypropyl-1-methyl)-L-cysteine (HPMMA) were well correlated with 8-OHDG with coefficients higher than 0.82, indicating those VOCs might easily lead to DNA damage. In conclusion, our co-monitoring of metabolites of VOCs with 8-OHDG and OH-Cot in one method provides a robust analytical method, which not only suggests the potential adverse health effects induced by VOCs but also discriminates and evaluates the contribution of passive smoking in human VOC exposure. Graphical abstract.


Assuntos
8-Hidroxi-2'-Desoxiguanosina/urina , Cromatografia Líquida/métodos , Cotinina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Compostos Orgânicos Voláteis/urina , 8-Hidroxi-2'-Desoxiguanosina/normas , Estudos de Casos e Controles , Cotinina/normas , Cotinina/urina , Humanos , Isótopos de Nitrogênio , Padrões de Referência , Fumar/urina , Compostos Orgânicos Voláteis/normas
5.
Sensors (Basel) ; 19(15)2019 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-31382683

RESUMO

Soil organic matter (SOM) is a major indicator of soil fertility and nutrients. In this study, a soil organic matter measuring method based on an artificial olfactory system (AOS) was designed. An array composed of 10 identical gas sensors controlled at different temperatures was used to collect soil gases. From the response curve of each sensor, four features were extracted (maximum value, mean differential coefficient value, response area value, and the transient value at the 20th second). Then, soil organic matter regression prediction models were built based on back-propagation neural network (BPNN), support vector regression (SVR), and partial least squares regression (PLSR). The prediction performance of each model was evaluated using the coefficient of determination (R2), root-mean-square error (RMSE), and the ratio of performance to deviation (RPD). It was found that the R2 values between prediction (from BPNN, SVR, and PLSR) and observation were 0.880, 0.895, and 0.808. RMSEs were 14.916, 14.094, and 18.890, and RPDs were 2.837, 3.003, and 2.240, respectively. SVR had higher prediction ability than BPNN and PLSR and can be used to accurately predict organic matter contents. Thus, our findings offer brand new methods for predicting SOM.


Assuntos
Nariz Eletrônico , Solo/química , Calibragem , Gases/química , Análise dos Mínimos Quadrados , Redes Neurais de Computação , Máquina de Vetores de Suporte/normas , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/normas
6.
J Complement Integr Med ; 16(3)2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30870142

RESUMO

Background Herbal medicines have been used in the treatment of liver diseases for a long time. In recent years, the use of herbal medicines for protection from other strong antibiotics as well as drugs that can damage the liver during their metabolism in liver and for treatment of liver diseases has increased all over the world. It is important to mention that a number of organic solvents are used at different stages of extraction/formulation development for these traditional preparations in industries/pharmacies. In addition, some of these solvents possess established carcinogenic properties and may enter the formulation as residual solvents. Hence as per ICH guidelines it is mandatory to keep the level of these solvents up to permissible limits. There has been a lot of hue and cry that ayurvedic formulations available in the market are not properly standardized for their quality due to lack of stringent regulations and standards from regulatory authorities. Therefore the aim of present work was to assess the compliance of ICH guidelines for level of organic volatile impurities in common marketed ayurvedic hepatic formulations. Methods In this study, 25 ayurvedic herbal formulations available as OTC product have been assessed for presence of residual solvents using gas chromatography with flame ionization detector. Results This study on 25 fast moving hepatic formulations in the market reflects that no residual solvents were detected in any of the formulations however if present were within prescribed permissible limits of ICH guidelines. The data was also subjected to statistical analysis (F-test and t-test at 95% confidence level). Conclusions Results indicate the safety of these hepatic formulations with respect to residual solvents. In addition presents a simple, linear, specific, accurate, precise and rugged gas chromatographic method for estimation of residual solvents.


Assuntos
Composição de Medicamentos/normas , Ayurveda/normas , Extratos Vegetais/análise , Extratos Vegetais/normas , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa , Contaminação de Medicamentos , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Compostos Orgânicos Voláteis/normas
7.
Ecotoxicol Environ Saf ; 176: 132-136, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30925329

RESUMO

In this study, occupational exposure to volatile organic compounds (VOCs) in the rendering plant of poultry slaughterhouse was determined and subsequently, carcinogen and non-carcinogenic risks were assessed using the US Environmental Protection Agency (USEPA). National Institute for Occupational Safety and Health (NIOSH) methods of 1501 and 1600 were used to measure VOCs in the breathing zone of the workers. Samples were analyzed by GC/MS. Carcinogenic and non-carcinogenic risks and sensitivity analysis were carried out using Monte Carlo simulations technique. The concentration of benzene and CS2 was higher than the occupational exposure limits (OEL). The hazard quotient (HQ) values for all measured compounds was more than 1, which indicating the high potential for non-carcinogenic risks. Furthermore, the calculated Lifetime Cancer Risks (LCR) for carcinogenic compounds revealed that cancer risk due to benzene is higher than the maximum acceptable level provided by USEPA (10-6). Based on the sensitivity analysis, the concentration and exposure frequency are the most important variable influencing both carcinogen and non-carcinogenic risks. Therefore, the concentration levels of the VOCs and exposure frequency should be controlled using engineering control measures.


Assuntos
Matadouros , Poluentes Ocupacionais do Ar/análise , Exposição Ocupacional/análise , Aves Domésticas , Compostos Orgânicos Voláteis/análise , Poluentes Ocupacionais do Ar/normas , Animais , Carcinógenos/análise , Carcinógenos/normas , Monitoramento Ambiental , Humanos , Exposição Ocupacional/normas , Medição de Risco , Compostos Orgânicos Voláteis/normas
8.
Indoor Air ; 28(1): 181-187, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28833742

RESUMO

Emission testing of products is currently a rapidly increasing field of measurement activity. Labeling procedures for construction products are based on such emission test chamber measurements, and hence, measurement performance should be verified. One possible route is to conduct testing of one material in different laboratories within a round robin test (RRT), ideally using homogeneous reference materials, which can be used within interlaboratory studies or as part of the quality management system to ensure comparable results. The applicability of a lacquer system with nine added VOCs (hexanal, styrene, n-decane, limonene, 2-ethyl-1-hexanol, N-methyl-α-pyrrolidone, 2-ethylhexyl acrylate, dimethyl phthalate, and n-hexadecane) was evaluated in an international RRT with 55 participating laboratories. An intralaboratory quality check confirmed the homogeneity and reproducibility of the lacquer material for most of the compounds (RSD 5%-6%), which was confirmed in the RRT. However, emissions varied for the polar compound N-methyl-α-pyrrolidone and the higher boiling compounds 1,2-dimethyl phthalate, and n-hexadecane which could be traced back to analytical issues. In the RRT, the interlaboratory relative standard deviations (RSDs) ranged from 30% to 65% for all participants but for reference laboratories the range was between 20% and 45%.


Assuntos
Materiais de Construção/análise , Teste de Materiais , Compostos Orgânicos Voláteis/normas , Ar/análise , Padrões de Referência , Compostos Orgânicos Voláteis/análise , Volatilização
9.
Anal Chem ; 89(19): 10461-10467, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28930436

RESUMO

A new tobacco filler Standard Reference Material (SRM) has been issued by the National Institute of Standards and Technology (NIST) in September 2016 with certified and reference mass fraction values for nicotine, N-nitrosonornicotine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, and volatiles. The constituents have been determined by multiple analytical methods with measurements at NIST and at the Centers for Disease Control and Prevention, and with confirmatory measurements by commercial laboratories. This effort highlights the development of the first SRM for reduced nicotine and reduced tobacco-specific nitrosamines with certified values for composition.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos , Produtos do Tabaco/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/normas , Congelamento , Cromatografia Gasosa-Espectrometria de Massas/normas , Nicotina/análise , Nicotina/normas , Nitrosaminas/análise , Nitrosaminas/normas , Transição de Fase , Padrões de Referência , Espectrometria de Massas em Tandem/normas , Produtos do Tabaco/normas , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/normas
10.
J Chromatogr A ; 1514: 16-28, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28765001

RESUMO

Volatile organic compounds (VOCs) are commonly collected from gaseous samples by adsorption to materials such as the porous polymer Tenax TA. Adsorbed compounds are subsequently released from these materials by thermal desorption (TD) and separated then by gas chromatography (GC) with flame ionization (FID) or mass spectrometry (MS) detection. Tenax TA is known to be particularly suitable for non-polar to semipolar volatiles, however, many volatiles from environmental and biological samples possess a rather polar character. Therefore, we tested if the polymer XAD-2, which so far is widely used to adsorb organic compounds from aqueous and organic solvents, could provide a broader coverage for (semi)polar VOCs during gas-phase sampling. Mixtures of volatile compounds covering a wide range of volatility (bp. 20-256°C) and different chemical classes were introduced by liquid spiking into sorbent tubes with one of the two porous polymers, Tenax TA or XAD-2, and analyzed by TD/GC-MS. At first, an internal standard mixture composed of 17 authentic standards was used to optimize desorption temperature with respect to sorbent degradation and loading time for calibration. Secondly, we tested the detectability of a complex standard mixture composed of 57 volatiles, most of them common constituents of the body odor of mammals. Moreover, the performance of XAD-2 compared with Tenax TA was assessed as limit of quantitation and linearity for the internal standard mixture and 33 compounds from the complex standard mixture. Volatiles were analyzed in a range between 0.01-∼250ng/tube depending on the compound and material. Lower limits of quantitation were between 0.01 and 3 ng±<25% RSD (R2>0.9). Interestingly, we found different kinetics for compound adsorption with XAD-2, and a partially better sensitivity in comparison with Tenax TA. For these analytes, XAD-2 might be recommended as an alternative of Tenax TA for TD/GC-MS analysis.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise , Adsorção , Animais , Cromatografia Gasosa-Espectrometria de Massas/normas , Gases/química , Odorantes/análise , Polímeros/análise , Polímeros/química , Padrões de Referência , Solventes/química , Temperatura , Compostos Orgânicos Voláteis/normas
11.
Yakugaku Zasshi ; 136(6): 791-3, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-27252055

RESUMO

People spend more than two thirds of their daily time indoors. Hence, maintaining a healthy indoor environment is indispensable for the prevention of building related illness. In Japan, guidelines for indoor air quality have been established for 13 volatile/semi-volatile organic compounds (VOCs/SVOCs). These guidelines are now under revision by the Committee on Sick House Syndrome: Indoor Air Pollution. In order to gain information on the current indoor air pollutants and their levels, we carried out a nation-wide survey of VOCs and aldehydes in indoor residential air during 2012-2013. In this review, I concisely summarized the current indoor air quality of Japan.


Assuntos
Poluição do Ar em Ambientes Fechados , Saúde Ambiental , Poluição do Ar em Ambientes Fechados/análise , Aldeídos/análise , Guias como Assunto , Humanos , Japão , Medição de Risco , Síndrome do Edifício Doente/etiologia , Síndrome do Edifício Doente/prevenção & controle , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/normas
12.
Bioanalysis ; 8(7): 677-90, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26978667

RESUMO

Analysis of volatile organic compounds (VOCs) from breath or clinical samples for disease diagnosis is an attractive proposition because it is noninvasive and rapid. There are numerous studies showing its potential, yet there are barriers to its development. Sampling and sample handling is difficult, and when coupled with a variety of analytical instrumentation, the same samples can give different results. Background air and the environment a person has been exposed to can greatly affect the VOCs emitted by the body; however, this is not an easy problem to solve. This review investigates the use of VOCs in disease diagnosis, the analytical techniques employed and the problems associated with sample handling and standardization. It then suggests the barriers to future development.


Assuntos
Testes Respiratórios , Cromatografia Gasosa-Espectrometria de Massas , Pneumopatias/diagnóstico , Compostos Orgânicos Voláteis/análise , Líquidos Corporais/química , Cromatografia Gasosa-Espectrometria de Massas/normas , Humanos , Manejo de Espécimes , Compostos Orgânicos Voláteis/normas
13.
Int J Environ Res Public Health ; 12(12): 15040-57, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26633433

RESUMO

At hazardous waste sites, volatile chemicals can migrate through groundwater and soil into buildings, a process known as vapor intrusion. Due to increasing recognition of vapor intrusion as a potential indoor air pollution source, in 2015 the U.S. Environmental Protection Agency (EPA) released a new vapor intrusion guidance document. The guidance specifies two conditions for demonstrating that remediation is needed: (1) proof of a vapor intrusion pathway; and (2) evidence that human health risks exceed established thresholds (for example, one excess cancer among 10,000 exposed people). However, the guidance lacks details on methods for demonstrating these conditions. We review current evidence suggesting that monitoring and modeling approaches commonly employed at vapor intrusion sites do not adequately characterize long-term exposure and in many cases may underestimate risks. On the basis of this evidence, we recommend specific approaches to monitoring and modeling to account for these uncertainties. We propose a value of information approach to integrate the lines of evidence at a site and determine if more information is needed before deciding whether the two conditions specified in the vapor intrusion guidance are satisfied. To facilitate data collection and decision-making, we recommend a multi-directional community engagement strategy and consideration of environment justice concerns.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Atmosféricos/normas , Água Subterrânea/análise , Água Subterrânea/normas , Poluentes do Solo/análise , Poluentes do Solo/normas , Poluentes Químicos da Água/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental/normas , Recuperação e Remediação Ambiental/normas , Guias como Assunto , Locais de Resíduos Perigosos/normas , Humanos , Estados Unidos , United States Environmental Protection Agency , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/normas , Poluentes Químicos da Água/normas
14.
Sci Total Environ ; 538: 712-23, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26327639

RESUMO

A regional survey of eight volatile organic compounds (VOCs), namely BTEX (benzene, toluene, ethylbenzene and p-xylene) and four chlorinated aliphatic hydrocarbons (CAHs: chloroform, 1,2-dichloroethane, trichloroethene and tetrachloroethene), was carried out at 174 sites, in 17 alluvial aquifers of Abruzzo, a Mediterranean region of southern Italy, from 2004 to 2009. Frequency of detection, concentration range, spatial distribution pattern, and temporal trend of contaminant concentration in each aquifer were analyzed as well as the relationships between VOC concentrations and the total amount of precipitation during the 90days preceding each sampling date. A review of published ecotoxicological data, providing an indication of the biological risk associated with the observed levels of VOC contamination, was presented and discussed. BTEX concentrations were under detection limits in all the investigated aquifers, indicating absence of contamination. In contrast, CAH contamination occurred in 14 out of 17 aquifers. The two most frequently detected compounds were chloroform and tetrachloroethene. No significant temporal trend was observed for chloroform and tetrachloroethene concentrations during the six years of observation, indicating the persistence of stable contaminations, except for some slightly decreasing trends observed in three out of 17 aquifers. In four aquifers chloroform and tetrachloroethene concentrations increased with precipitations in the preceding months. Spatial patterns of contamination differed among aquifers, indicating highly complex contaminant distributions at aquifer scale not related to single-plume geometries. Patterns of contamination by chloroform and tetrachloroethene in the most urbanized aquifers were likely associated with multiple sources of VOCs not clearly detectable at the scale used in this study. In five out of 17 aquifers, chloroform and tetrachloroethene co-occurred at concentrations that are lethal to groundwater-dwelling organisms under a short exposure period (four days). Future studies should therefore consider the possibility that in the other aquifers groundwater-dwelling organisms might be physiologically damaged by sublethal VOC concentrations.


Assuntos
Monitoramento Ambiental , Água Subterrânea/química , Compostos Orgânicos Voláteis/análise , Poluentes Químicos da Água/análise , Região do Mediterrâneo , Compostos Orgânicos Voláteis/normas , Poluentes Químicos da Água/normas
15.
Am J Ind Med ; 58(2): 193-202, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25603941

RESUMO

OBJECTIVES: The City of San Francisco, California established a recognition program for nail salons that use safer nail products and receive worker safety training. This pilot study examined whether participating salons had reduced levels of toluene, methyl methacrylate (MMA), and total volatile organic compounds (TVOC), and improved knowledge and behavior compared to control salons. METHODS: We conducted personal air monitoring and administered surveys assessing knowledge and behaviors of two workers from each of six intervention salons and five control salons. We conducted assessments before and after the worker training. RESULTS: Although non-significant, there was a reduction in toluene (-46% vs. 0%) and TVOC (-19% vs. +47%), but an increase in MMA (+113% and +72%) among intervention salons compared to control salons. Awareness of dibutyl phthalates in nail products increased (+55%) among intervention salons between surveys. CONCLUSIONS: A government-administered nail salon recognition program may reduce chemical exposures and increase work-related knowledge.


Assuntos
Poluentes Ocupacionais do Ar/normas , Indústria da Beleza/normas , Promoção da Saúde , Exposição Ocupacional/normas , Poluentes Ocupacionais do Ar/análise , Segurança Química/normas , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Metilmetacrilato/análise , Unhas , Exposição Ocupacional/análise , Saúde Ocupacional/normas , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , São Francisco , Solventes/análise , Solventes/normas , Tolueno/análise , Tolueno/normas , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/normas
16.
Anal Bioanal Chem ; 407(11): 3225-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25450051

RESUMO

The Brazilian Metrology Institute (National Institute of Metrology, Quality, and Technology, Inmetro) has been developing a certified reference material (CRM) of the volatile organic compounds benzene; toluene; ethylbenzene; and ortho, meta, and para-xylenes (BTEX) in methanol, to ensure quality control for environmental-analysis measurements. The objective of this paper is to present the results of certification studies: uncertainty estimates related to characterization, a homogeneity study, and a stability study on a single lot of CRM composed of BTEX in methanol. The method used analysis of variance (ANOVA), a statistical tool, to evaluate the homogeneity and stability of the BTEX CRM, which complies with ISO Guide 30 series. The homogeneity and stability of the BTEX CRM was confirmed for all analytes and their respective properties. All the procedures used in this study complied with ISO GUIDE 34, ISO GUIDE 35, and the guide to the expression of uncertainty of measurement (GUM).


Assuntos
Monitoramento Ambiental/normas , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/normas , Análise de Variância , Benzeno/análise , Derivados de Benzeno/análise , Monitoramento Ambiental/métodos , Metanol/análise , Padrões de Referência , Tolueno/análise , Incerteza , Xilenos/análise
17.
Anal Bioanal Chem ; 407(11): 3231-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25543146

RESUMO

Emission test chamber measurement is necessary to proof building materials as sources of volatile organic compounds (VOCs). The results of such measurements are used to evaluate materials and label them according to their potential to emit harmful substances, polluting indoor air. If only labelled materials were installed indoors, this would improve indoor air quality and prevent negative impacts on human health. Because of the complex testing procedure, reference materials for the quality assurance are mandatory. Currently, there is a lack of such materials because most building products show a broad variation of emissions even within one batch. A previous study indicates lacquers, mixed with volatile organic pollutants, as reproducible emission source for a wide range of substances. In the present study, the curing of the lacquer-VOC mixture inside micro-chambers was optimised. Therefore, the humidity and the chamber flow were varied. Typical indoor air pollutants with a wide range of volatilities, for example, styrene, n-hexadecane, dimethyl and dibutyl phthalate were selected. It turned out that, under optimised curing parameters inside the micro-chamber, their emission can be reproduced with variations of less than 10 %. With this, a next important step towards a reference material for emission testing was achieved.


Assuntos
Laca/análise , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/normas , Poluição do Ar em Ambientes Fechados/análise , Alcanos/análise , Alcanos/normas , Dibutilftalato/análise , Dibutilftalato/normas , Umidade , Teste de Materiais , Ácidos Ftálicos/análise , Ácidos Ftálicos/normas , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Estireno/análise , Estireno/normas
19.
Talanta ; 111: 111-8, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23622533

RESUMO

An UV-Ion Mobility Spectrometer is a simple, rapid, inexpensive instrument widely used in environmental analysis among other fields. The advantageous features of its underlying technology can be of great help towards developing reliable, economical methods for determining gaseous compounds from gaseous, liquid and solid samples. Developing an effective method using UV-Ion Mobility Spectrometry (UV-IMS) to determine volatile analytes entails using appropriate gaseous standards for calibrating the spectrometer. In this work, two home-made sample introduction systems (SISs) and a commercial gas generator were used to obtain such gaseous standards. The first home-made SIS used was a static head-space to measure compounds present in liquid samples and the other home-made system was an exponential dilution set-up to measure compounds present in gaseous samples. Gaseous compounds generated by each method were determined on-line by UV-IMS. Target analytes chosen for this comparative study were ethanol, acetone, benzene, toluene, ethylbenzene and xylene isomers. The different alternatives were acceptable in terms of sensitivity, precision and selectivity.


Assuntos
Gases/análise , Análise Espectral/métodos , Raios Ultravioleta , Compostos Orgânicos Voláteis/análise , Acetona/análise , Acetona/química , Benzeno/análise , Benzeno/química , Derivados de Benzeno/análise , Derivados de Benzeno/química , Calibragem , Etanol/análise , Etanol/química , Gases/química , Gases/normas , Íons/química , Padrões de Referência , Reprodutibilidade dos Testes , Análise Espectral/instrumentação , Tolueno/análise , Tolueno/química , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/normas , Xilenos/análise , Xilenos/química
20.
Lab Chip ; 13(5): 851-9, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23295709

RESUMO

This study reports on dual on-column Fabry-Pérot (FP) cavity sensor-based gas chromatography (GC) of mixtures of volatile organic compounds (VOCs) utilizing an on-chip device, the so called "microfabricated passive preconcentrator/injector (µPPI)". Comprehensive analysis of the sampling, desorption/injection, and compound separation performance of the µPPI-based optofluidic GC system is described. Here, the combined use of the µPPI and on-column FP cavity sensors in a common GC platform enabled diffusion-based passive sampling, rapid (<7 min) chromatographic separation, and optical detection for the quaternary VOC mixtures of benzene, TCE, toluene, and m-xylene at sub-ppm concentrations with a simpler fluidic setup than conventional GC systems. The FP cavity sensor arrangement provided the means to study the dynamics of the thermal desorption/injection of VOCs by the µPPI and its effect on the GC separation resolution. Our analysis of obtained chromatograms revealed a presence of the competitive adsorptions of VOC mixtures onto the adsorption sites of trapping materials in the µPPI, which decreased the effective sampling rate by ~50% for compounds with high volatility. The validated performance of the optofluidic GC system promises future development of a field deployable GC microsystem incorporating the µPPI and the FP cavity sensors.


Assuntos
Cromatografia Gasosa/métodos , Técnicas Analíticas Microfluídicas/métodos , Compostos Orgânicos Voláteis/análise , Calibragem , Cromatografia Gasosa/instrumentação , Cromatografia Gasosa/normas , Gases/química , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/normas , Fenômenos Ópticos , Temperatura , Compostos Orgânicos Voláteis/isolamento & purificação , Compostos Orgânicos Voláteis/normas
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