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1.
Molecules ; 26(2)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467697

RESUMO

Lacquer sap has been used by humans from antiquitywhen it was treated as a luxury item because of its desirable physical properties. In modern times, although access barriers are lower, lacquer is still considered to be rare and valuable. Thus, low quality, inexpensive Vietnamese and Myanmarese lacquers and cashew nutshell liquid are frequently added to the costly Toxicodendron vernicifluum lacquer sap from Korea, China, and Japan. However, these blended lacquers can diminish the quality of artisan works. The Toxicodendron vernicifluum lacquer saps mixed with other natural lacquers were characterized using time-of-flight secondary-ion mass spectrometry (ToF-SIMS) and high-performance liquid chromatography (HPLC). ToF-SIMS provided the chemical structure of the lacquer monomer, copolymerized dimers, trimers, etc. HPLC provided quantitative analysis of the components of a randomly mixed lacquer. These techniques can be used to control the quality of commercial lacquer sap for the Asian lacquer industry and the traditional conservation of ancient objects.


Assuntos
Produtos Biológicos/análise , Laca/análise , Toxicodendron/química , Árvores/química , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Espectrometria de Massa de Íon Secundário/métodos
2.
Anal Bioanal Chem ; 410(22): 5391-5403, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29516137

RESUMO

An untargeted strategy aiming at identifying non-intentionally added substances (NIAS) migrating from coatings was developed. This innovative approach was applied to two polyester-polyurethane lacquers, for which suppliers previously provided the identity of the monomers involved. Lacquers were extracted with acetonitrile and analyzed by liquid chromatography-high resolution mass spectrometry (LC-HRMS). Data, acquired in the full scan mode, were processed using an open-source R-environment (xcms and CAMERA packages) to list the detected features and deconvolute them in groups related to individual compounds. The most intense groups, accounting for more than 85% of cumulated feature intensities, were then investigated. A homemade database, populated with predicted polyester oligomer combinations from a relevant selection of diols and diacids, enabled highlighting the presence of 14 and 17 cyclic predicted polyester oligomers in the two lacquers, including three mutual combinations explained by common known monomers. Combination hypotheses were strengthened by chromatographic considerations and by the investigation of fragmentation patterns. Regarding unpredicted migrating substances, four monomers were hypothesised to explain several polyester or caprolactam oligomer series. Finally, considering both predicted and tentatively elucidated unpredicted oligomers, it was possible to assign hypotheses to features representing up to 82% and 90% of the cumulated intensities in the two lacquers, plus 9% and 3% (respectively) originating from the procedural blank. Graphical abstract Elucidation of non-intentionally added substances.


Assuntos
Contaminação de Alimentos/análise , Embalagem de Alimentos , Análise de Perigos e Pontos Críticos de Controle/métodos , Laca/análise , Poliésteres/análise , Poliuretanos/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Embalagem de Alimentos/métodos
3.
Mycoses ; 60(12): 800-807, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28925059

RESUMO

Patient adherence is a key consideration in the choice of a topical regimen for the treatment of onychomycosis. The objective of this study was to investigate patient-reported outcomes (treatment utilisation, adherence and satisfaction) in onychomycosis treated with once-weekly amorolfine 5% nail lacquer versus once-daily ciclopirox 8% nail lacquer (Study A) or once-daily urea 40% ointment/bifonazole 1% cream combination regimen (Study B). Study A: Subjects received amorolfine and ciclopirox on opposite feet for 12 weeks. Study B: Subjects received amorolfine and urea/bifonazole on opposite feet for 6-7 weeks. Assessments included subject adherence as per label, treatment preference and questionnaire. Study A: More subjects adhered to amorolfine (85%) than to ciclopirox (60%) (P = .025). Overall, subjects were satisfied (95% vs 100%, respectively) and the treatments were balanced in terms of preference (50% vs 45%) at week 12. Study B: More subjects adhered to amorolfine dosage (81.8%) than to the dosage of the urea/bifonazole combination regimen (59.1%) (P = .096). At the end of study, 85.7% of subjects preferred amorolfine versus 14.3% for urea/bifonazole. Fewer subjects experienced local side effects with amorolfine (4.5%) compared to urea (27.3%) and bifonazole (15%). Amorolfine 5% nail lacquer offers a simple and convenient treatment option, which may result in improved patient adherence and consequently lead to improved efficacy and patient satisfaction.


Assuntos
Antifúngicos/administração & dosagem , Dermatoses do Pé/tratamento farmacológico , Morfolinas/administração & dosagem , Onicomicose/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Ciclopirox , Esquema de Medicação , Feminino , Dermatoses do Pé/psicologia , Humanos , Imidazóis/administração & dosagem , Laca/análise , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Morfolinas/análise , Onicomicose/psicologia , Medidas de Resultados Relatados pelo Paciente , Piridonas/administração & dosagem
4.
Biosci Biotechnol Biochem ; 81(6): 1165-1175, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28485213

RESUMO

Lacquer tree sap, a raw material of traditional paints in East Asia, is hardened through laccase-catalyzed oxidation and the following polymerization of phenolic compound urushiol. In the sap's water-insoluble fraction, we found two plantacyanins and a ferritin 2 domain-containing protein (TvFe2D, a homolog of Arabidopsis AT1G47980 and AT3G62730). The recombinant TvFe2D protein suppressed the accumulation of laccase-catalyzed oxidation products of a model substrate syringaldazine without decreasing oxygen consumption, the second substrate of laccase. The suppression was also observed when another substrate guaiacol or another oxidizing enzyme peroxidase was used. The functional domain of the suppression was the C-terminal half, downstream of the ferritin 2 domain. The results suggest that this protein may be involved in regulating the sap polymerization/hardening. We also discuss the possibility that homologous proteins of TvFe2D in other plants might be involved in the laccase- or peroxidase-mediated polymerization of phenolic compounds, such as lignin and flavonoids.


Assuntos
Regulação da Expressão Gênica de Plantas , Lacase/metabolismo , Laca/análise , Metaloproteínas/metabolismo , Peroxidases/metabolismo , Proteínas de Plantas/metabolismo , Toxicodendron/metabolismo , Sequência de Aminoácidos , Biocatálise , Catecóis/metabolismo , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Ferritinas/química , Guaiacol/metabolismo , Hidrazonas/metabolismo , Cinética , Lacase/genética , Lignina/metabolismo , Metaloproteínas/genética , Oxirredução , Consumo de Oxigênio , Peroxidases/genética , Proteínas de Plantas/genética , Polimerização , Domínios Proteicos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Toxicodendron/química , Árvores
5.
J Pharm Sci ; 106(6): 1570-1577, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28263845

RESUMO

Onychomycosis is a fungal nail infection. The development of new topical antifungal agents for the treatment of onychomycosis has focused on formulation enhancements that optimize the pharmacological characteristics required for its effective treatment. Polyurethanes (PUs) have never been used in therapeutic nail lacquers. The aim of this work has been the development of new PU-based nail lacquers with antifungal activity containing 1.0% (wt/wt) of terbinafine hydrochloride. The biocompatibility, wettability, and the prediction of the free volume in the polymeric matrix were assessed using a human keratinocytes cell line, contact angle, and Positron Annihilation Lifetime Spectroscopy determinations, respectively. The morphology of the films obtained was confirmed by scanning electron microscopy, while the nail lacquers' bioadhesion to nails was determined by mechanical tests. Viscosity, in vitro release profiles, and antifungal activity were also assessed. This study demonstrated that PU-terbinafine-based nail lacquers have good keratinocyte compatibility, good wettability properties, and adequate free volume. They formed a homogenous film after application, with suitable adhesion to the nail plate. Furthermore, the antifungal test results demonstrated that the terbinafine released from the nail lacquer Formulation A PU 19 showed activity against dermatophytes, namely Trichophyton rubrum.


Assuntos
Antifúngicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Laca/análise , Unhas/microbiologia , Naftalenos/administração & dosagem , Poliuretanos/análise , Adesivos/química , Antifúngicos/farmacologia , Linhagem Celular , Fungos/efeitos dos fármacos , Humanos , Naftalenos/farmacologia , Onicomicose/tratamento farmacológico , Terbinafina , Molhabilidade
6.
Food Chem Toxicol ; 81: 46-53, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25865937

RESUMO

Toluene and dibutyl phthalate (DBP) are found in many consumer products, including cosmetics, synthetic fragrances, and nail polish. In 2012, the California Environmental Protection Agency evaluated 25 nail products and found that 83% of the products that claimed to be toluene-free contained toluene at concentrations ranging up to 190,000 ppm, and 14% of the products that claimed to be DBP-free contained DBP at concentrations ranging up to 88,000 ppm. We conducted a preliminary, screening-level analysis of the potential toluene and DBP-related health risks to consumers and professionals based on the medium and maximum concentrations of toluene and DBP presented in the 2012 report and evaluated dermal and inhalation exposure to a salon patron, nail technician, and home user. We concluded that the maximum toluene concentration for the technician and home user scenarios exceeded the California MADL, but the estimated air concentrations did not exceed the Federal or Cal OSHA PEL. The MADL for DBP was exceeded for all user scenarios at both the median and maximum concentrations. Using these highly conservative assumptions, exposures above regulatory limits could possibly occur during routine use of nail products; further research is needed in order to evaluate potential human health risks.


Assuntos
Cosméticos/análise , Dibutilftalato/análise , Laca/análise , Medição de Risco , Tolueno/análise , California , Cosméticos/toxicidade , Dibutilftalato/toxicidade , Relação Dose-Resposta a Droga , Humanos , Exposição por Inalação , Laca/toxicidade , Unhas , Tolueno/toxicidade
7.
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
8.
Chemosphere ; 107: 224-229, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24418066

RESUMO

Volatile organic compounds (VOCs) found indoors have the potential to affect human health. Typical sources include building materials, furnishings, cleaning agents, etc. To address this risk, chemical emission testing is used to assess the potential of different materials to pollute indoor air. One objective of the European Joint Research Project "MACPoll" (Metrology for Chemical Pollutants in Air) aims at developing and testing a reference material for the quality control of the emission testing procedure. Furthermore, it would enable comparison of measurement results between test laboratories. The heterogeneity of the majority of materials makes it difficult to find a suitable reference sample. In the present study, styrene, 2-ethyl-1-hexanol, N-methyl-α-pyrrolidone, lindane, n-hexadecane, 1,2-dimethyl- and 1,2-di-n-butyl-phthalate were added to 12 commercially available lacquers (6 alkyd and 6 acrylic polymer based lacquers) serving as carrier substrate. After homogenization, the mixtures were loaded into a Markes Micro-Chamber/Thermal Extractor (µ-CTE™) for curing and investigation of the emission behavior for each compound. For almost all of the investigated chemicals, the preferred glossy acrylic lacquer showed emissions that were reproducible with a variation of less than 20% RSD. Such lacquer systems have therefore been shown to be good candidates for use as reference materials in inter-laboratory studies.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Compostos Orgânicos Voláteis/química , Laca/análise , Reprodutibilidade dos Testes
9.
Environ Sci Technol ; 47(20): 11734-8, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24070094

RESUMO

So far, conventional processes that have been employed to delacquer the paints decorated on used beverage cans (UBCs) are less than satisfactory in economic and environmental effect. Therefore, a new method combining vacuum pyrolysis with dilute sulfuric acid leaching to delacquer the paints was investigated. The results of vacuum pyrolysis showed that the decoating rate increased with the increase of temperature and the paints were almost 100% removed from UBCs under the following conditions: temperature of 650 °C, holding time of 20 min, and residual gas pressure lower than 0.1 kPa. The pyrolysis oil was mainly composed of phenol and 2-methy-phenol analyzed by GC-MS. The delacquered UBCs were subsequently leached with 5% H2SO4 for 60 s and TiO2 was recovered by calcining the residuals in muffle furnace at 450 °C for 15 min. This innovative technology offers an effective method to delacquer paints from UBCs, which obtains excellent stripping effect and avoids the production of toxic substances generated in direct combustion process. Furthermore, the pyrolysis oil can be reused as chemical feedstock in other fields.


Assuntos
Bebidas , Laca/análise , Reciclagem/métodos , Temperatura , Vácuo , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Sulfúricos/química , Fatores de Tempo , Difração de Raios X
10.
Analyst ; 138(19): 5685-96, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-23897515

RESUMO

Oriental lacquer has been used in Asian countries for thousands of years as a durable and aesthetic coating material for its adhesive, consolidating, protective and decorative properties. Although these objects are made from an unusual material in Occident, Western museum collections host many lacquerwares. Curators, restorers and scientists are daily confronted with questions of their conservation and their alteration. The characterization of their conservation state is usually assessed through visual observations. However deterioration often starts at the microscopic level and cannot be detected by a simple visual inspection. Often, ageing and deterioration of artworks are connected to physical, mechanical and chemical transformations. Thus new insight into alteration of lacquer involves the monitoring of macro-, microscopic and molecular modifications, and this can be assessed from physico-chemical measurements. Non-invasive (microtopography and Scanning Electron Microscopy - SEM) and micro-invasive (infrared micro-spectroscopy using a synchrotron source - SR-µFTIR) investigations were performed to study the degradation processes of lacquers and evaluate their level of alteration. In particular, spectral decomposition and fitting procedure were performed in the 1820-1520 cm(-1) region to follow the shift of the C=O and C=C band positions during lacquer ageing. The present work proves the potential of this physico-chemical approach in conservation studies of lacquers and in the quantification of the state of alteration. It evidences chemical phenomena of alteration such as oxidation and decomposition of a lacquer polymeric network. It also demonstrates for the first time the degradation front of artificially aged lacquer and the chemical imaging of a more than 2000 years old archaeological lacquer by using SR-µFTIR.


Assuntos
Fenômenos Químicos , Laca/análise , Imagem Multimodal/métodos , Árvores , Ásia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Árvores/química
11.
Eur J Pharm Sci ; 45(1-2): 150-7, 2012 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-22108348

RESUMO

A sealability of aluminium lidding foils against formable polymer materials of blister packages is usually achieved by a coating of aluminium with certain grammages of heat seal lacquers. To investigate influences of their thickness on quality of blister packages, lidding foils with different grammages of two lacquer types were manufactured. Sealing experiments (variation of temperature, pressure and sealing time) were performed. Sealed seam strengths were determined with mechanical tensile tests, tightness of cold form blisters were analysed by means of helium leakage tests. Time-dependent moisture uptake of stored blisters was monitored with micro-gas chromatography. By means of a simple calculation model the permeability coefficients of the heat seal lacquers were determined. Lidding foils with higher lacquer grammages showed significantly greater sealed seam strengths. Helium leakage tests showed only slight effects of heat seal lacquer grammage on tightness of blisters. But cold form blisters with lidding foils of higher lacquer grammages showed a significantly greater moisture uptake. Since the heat seal lacquers and the rigid polyvinyl chloride of the formable aluminium compound foils had similar permeability coefficients, the contribution of the lacquers to the total permeability of the investigated cold form blisters was only slightly.


Assuntos
Embalagem de Medicamentos , Laca/análise , Cloreto de Polivinila/química , Algoritmos , Fenômenos Químicos , Alemanha , Laca/efeitos adversos , Teste de Materiais , Modelos Químicos , Permeabilidade , Pressão , Controle de Qualidade , Propriedades de Superfície , Temperatura , Resistência à Tração , Fatores de Tempo , Água/análise
12.
Molecules ; 15(6): 3920-31, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20657417

RESUMO

The dermatophytes are filamentous fungi that cause cutaneous fungal infections because they use keratin as a nutrient source. For this study the antidermatophyte activity of the extracts and derivates from leaves of Piper regnellii was analyzed. From the dichloromethane extract (EBD) neolignans such as eupomatenoid-3 and eupomatenoid-5 were obtained, and it was submitted to fractionation to remove the green residue, designated as the chloroform fraction (FF). Extracts, chloroform fraction and compounds were tested against Trichophyton rubrum ATCC 28189 to determine the minimum inhibitory concentration (MIC). The chloroform fraction was incorporated to nail lacquer that was analyzed by photoacoustic spectroscopy, in vitro assay and scanning electronic microscopy. For antifungal activity in solid medium the dichloromethane extract and chloroform fraction were used. The compounds eupomatenoid-3 and eupomatenoid-5 were less active than the dichloromethane extract against T. rubrum. EBD and FF showed moderate activity in hyphal growth inhibition in solid medium and EBD did not link to ergosterol. Nail lacquer containing the chloroform fraction showed good penetration through the nail as determined by photoacoustic spectroscopy. From in vitro studies it was observed that nail lacquer concentrations above 20 mg/mL prevented the growth of fungi, but concentrations up to 2.5 inhibited the growth. Scanning electronic microscopy was used to confirm the in vitro nail lacquer activity results. The specie P. regnellii showed great antifungal activity against T. rubrum, and nail lacquer containing its chloroform fraction has great potential to treat onychomycosis caused by these microorganisms.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Laca/análise , Piper/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Clorofórmio/química , Humanos , Cloreto de Metileno/química , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Trichophyton/efeitos dos fármacos
14.
Food Addit Contam ; 22(5): 490-502, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-16019822

RESUMO

The main objective was to develop a technique to expose spots of invisible set-off of inks and lacquers on the food-contact surface of food-packaging materials. Set-off is the unintentional transfer of components of printing inks from the outer printed surface onto the food-contact surfaces. The target sensitivity was 20 microg cm(-2) and the technique should be capable of examining large areas of printed substrate for no more than 4% coverage by set-off. These requirements equate to an ability to detect a worst-case migration potential of less than 50 microg kg(-1). Other objectives were the industrial requirements that the equipment should be inexpensive, should be easy to use by existing personnel and should preferably be non-destructive with a clear criterion for pass or fail. The approaches investigated included chemical analysis of solvent extracts, Fourier-transform infrared spectroscopy and microbeam analytical techniques, but these were found to be cumbersome and had only limited success. The objectives were achieved using an optical approach to excite and observe luminescence from invisible set-off. In model experiments, resins were applied to different substrates (plastic, paper and cartonboard). For a given resin on a given material, the key to success was to maximize the discrimination between the luminescence from the resin and that from the substrate by selecting the optimal combination of exciting wavelength and viewing goggles with selective wavelength filters. The required level of detection (20 microg cm(-2)) was achieved or exceeded for all ten resins tested on three different plastics. It was also achieved for two different papers and in all but four cases of the resins on three different cartonboards. Quantitation was achieved by the use of a calibration palette prepared using different quantities of resin spotted onto the relevant blank packaging material.


Assuntos
Embalagem de Alimentos , Tinta , Laca/análise , Microanálise por Sonda Eletrônica/métodos , Medições Luminescentes/métodos , Papel , Pigmentos Biológicos/química , Plásticos/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Propriedades de Superfície
15.
Se Pu ; 23(6): 663-8, 2005 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-16499002

RESUMO

The comparison method of fingerprints of the lacquer coat of cars (LCC) was established by using thermal desorption instrument with gas chromatography. The actual LCC samples were also analyzed. The samples were cut out to proper size and placed in the desorption furnace of the thermal desorption instrument. The volatile organic compounds in LCC were desorbed from the lacquer coat samples in the furnace under the chosen temperature, then separated in the capillary column and detected on a flame ionization detector of gas chromatography. The incipient judgment whether the two fingerprints of LCC were the same can be made from the contour and figure of the chromatograms. To make farther study of the two similar fingerprints, the overlap ratio of the peaks and relative retention values were given in the article. The two LCC samples can be regarded as the same if the overlap ratio of peaks was more than 90%, and the similarity of the ratio of relative retention times r(t2) and r(t1) and relative peak areas r(A2) and r(A1) in the two fingerprints were more than 99% and 70%, respectively. The method is good in repeatability and is easily carried out. The peaks in the fingerprint can be readily recognized. The fingerprint was characterized quantitatively. The method can be used in the department of traffic police and the comparison result can be used as material evidence in the court.


Assuntos
Automóveis , Cromatografia Gasosa/métodos , Laca/análise
16.
Ann Occup Hyg ; 44(8): 645-51, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11108786

RESUMO

Current methods for measuring dermal exposure to skin irritants and allergens, such as acrylates, have significant drawbacks for exposure assessment. A noninvasive sampling method has been developed and tested for measuring dermal exposure to a multifunctional acrylate employing a tape stripping of the nonviable epidermis (stratum corneum). Samples were subsequently extracted and a gas chromatographic method was employed for quantitative analysis of tripropylene glycol diacrylate (TPGDA). This method was tested in 10 human volunteers exposed to an a priori determined amount of TPGDA or a UV-radiation curable acrylate coating containing TPGDA (UV-resin) at different sites on hands and arms. On the average, the first tape stripping removed 94% (coefficient of variation 16%) of the theoretical quantity of deposited TPGDA and 89% (coefficient of variation 15%) of the theoretical quantity of deposited TPGDA in UV-resin 30min after exposure. Quantities of TPGDA recovered from two consecutive tape strippings accounted for all of the test agent, demonstrating both the efficiency of the method to measure dermal exposure and the potential to determine the rate of absorption with successive samples over time. In general, the amount removed by the first stripping was greater for TPGDA than for UV-resin while the second stripping removed approximately 6 and 21% of TPGDA and UV-resin, respectively. However, when the amounts removed with the first tape stripping for TPGDA or UV-resin from the five different individual sites were compared, no significant differences were observed (P=0.111 and 0.893, respectively). No significant difference was observed in recovery between TPGDA and UV-resin for the first tape stripping when calculated as a percentage of the theoretical amount (P=0.262). The results indicate that this tape-stripping technique can be used to quantify dermal exposure to multifunctional acrylates.


Assuntos
Acrilatos/análise , Monitoramento Ambiental/métodos , Laca/análise , Exposição Ocupacional/análise , Propilenoglicóis/análise , Absorção Cutânea , Adesivos , Análise de Variância , Braço , Mãos , Humanos , Manejo de Espécimes/métodos
17.
Ann Occup Hyg ; 44(8): 635-44, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11108785

RESUMO

The use of ultraviolet radiation-curable coatings (UV-coatings) has increased rapidly in the parquet and furniture industry. Work with UV-coatings involves risk from skin exposure to chemically reactive, concentrated acrylates that are known skin contact irritants and sensitizers. Yet, the methods and tools for measuring and quantifying dermal exposure from hazardous chemicals directly on the skin are limited and methods to measure skin exposure to UV-coatings in occupational or environmental settings have been lacking. Skin exposure to UV-coatings was measured employing a quantitative tape stripping method that we have developed for this purpose. A pilot study was performed at three workplaces. In the main study, workers' skin exposure to uncured UV-coatings was measured at seven workplaces and on two separate workdays (rounds 1 and 2) within a six-month period to determine exposure variation. Skin exposure was measured at four standardized sites on the hand, 3-4 times per work shift. The forehead was sampled once. A questionnaire was carried out with the workers in both rounds to find out factors that can affect skin exposure to UV-coatings. The pilot study indicated that both skin and surface contamination to TPGDA-containing UV-coatings were common and varied up to 2110 microgram on the sampling area of 10cm(2). In the main study skin contamination due to TPGDA was found on 16 of 23 workers, at 6 out of the 7 workplaces, and from 36 (5. 4%) of the 664 samples. In round one 8.6% (n=383) of the samples contained TPGDA and in round two 1.1 % (n=281). The average TPGDA mass on all the positive samples (n=36) was 30.4+/-77.0 microgram for the first and second rounds alone this mass was 30.6+/-80 (n=33) and 28.3+/-16.5 microgram (n=3), respectively. Despite the limited sampling area and sampling sites, we could find residues of TPGDA at all sampling times, even at the beginning of the work shift. This may be due to transfer of UV-coatings through contaminated equipment, shoes and surfaces. Our study indicates that there is a risk of harmful skin exposure to UV-coatings in the furniture and parquet industry.


Assuntos
Acrilatos/análise , Laca/análise , Exposição Ocupacional/análise , Propilenoglicóis/análise , Absorção Cutânea , Análise de Variância , Estudos de Casos e Controles , Pisos e Cobertura de Pisos , Mãos , Humanos , Exposição por Inalação/análise , Decoração de Interiores e Mobiliário , Exposição Ocupacional/prevenção & controle , Ocupações , Pintura/análise , Fatores de Tempo
19.
Se Pu ; 16(2): 173-5, 1998 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-11326989

RESUMO

This paper reports the separation and determination of monosaccharide composition in lacquer polysaccharide (LPS) by HPLC. The five monosaccharides were analyzed on microBondapak NH2 column (300 mm x 7.8 mm i.d. 10 microns) and refractive index detection. The mobile phase was CH3CN-H2O-CH3OH (70:25:5, V/V) flowing at a rate of 1.6 mL/min. These monosaccharides were identified by their retention times and quantitatively determined by their peak areas. LPS samples were hydrolysed with 2.0 mol/L CF3COOH. The linear correlation coefficients were all over 0.9953. The average recoveries of monosaccharides ranged 98.8%-103.6% and relative standard deviations were below 5%. The method is simple, rapid, precise, and has been used satisfactorilly for analysis of the monosaccharides hydrolyzed from LPS, which were isolated from sap of three kinds of Lac tree (Maoba Damu, Maoba Xiaomu and Jianshi) in Hubei province.


Assuntos
Laca/análise , Monossacarídeos/análise , Polissacarídeos/análise , Cromatografia Líquida de Alta Pressão , Árvores/química
20.
Int J Occup Med Environ Health ; 10(1): 79-88, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9187049

RESUMO

Evaluation of occupational exposure to solvent vapours in the production of paints and lacquers is presented. The measurements were carried out in 5 paint and lacquer producing plants of the varied level of technical and technological advancement. Evaluation of exposure was based on determination of all substances identified in the work environment. Analysis was performed by gas chromatography with MSD and FID. Standard mixtures composed of 40 substances were used for calibration. The determined levels of exposure were directly dependent on technical conditions and modernisation status in factories investigated. Measurements were carried out in the uniform analytical system, which assures comparability of the data from all the factories under study.


Assuntos
Poluentes Ocupacionais do Ar/análise , Indústria Química , Exposição Ocupacional , Solventes/análise , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Laca/análise , Pintura/análise , Polônia
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