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1.
J Occup Environ Hyg ; 21(7): 494-503, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38838303

RESUMEN

The objective was to study the interaction of the components of a complex liquid mixture on the permeation parameters of its constituents. A firearm cleaning solvent, Hoppes No. 9 Gun Bore Cleaner, was selected to challenge two varieties of disposable nitrile gloves, the thinnest (Kimberly-Clark Lavender) and thickest (Kimberly-Clark Blue), using the closed-loop ASTM F739 cell without recirculation and n-decane collection followed by quantitation of the permeated compounds using capillary gas chromatography-mass spectrometry. The thicker Blue glove resisted the permeation of Hoppe's relative to the thinner Lavender glove as shown by 3.2 times more mass permeated by the Lavender glove at 60 min despite the same standardized breakthrough times (7.5 ± 2.5 min). The kerosene fraction permeated faster at a much higher rate than expected. The Kimberly-Clark disposable nitrile glove chemical resistance guide lists a breakthrough time for kerosene of 82 min for Sterling disposable nitrile glove material. However, for Hoppe's the kerosene components appeared at the standardized breakthrough time. Mixture components that were reported by the glove manufacturer to quickly permeate the disposable nitrile material, such as ethanol, did not permeate at a rate slower than expected, indicative of a possible carrier function. A semiquantitative risk assessment confirmed the unacceptability of both gloves. Persons using personal protective equipment, such as gloves, may not be afforded the expected resistance to chemical permeation when chemicals are in a suitable mixture, hence enhancing the risk of exposure. More research is needed to produce better glove testing measures to ensure the safety of workers.


Asunto(s)
Armas de Fuego , Guantes Protectores , Nitrilos , Permeabilidad , Solventes , Nitrilos/química , Exposición Profesional/prevención & control , Exposición Profesional/análisis , Humanos , Ensayo de Materiales , Cromatografía de Gases y Espectrometría de Masas
2.
J Occup Environ Hyg ; 17(4): 135-164, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32209007

RESUMEN

This second part of the review of the 21st century literature on glove permeation is divided into the following major themes; permeation data and mathematical models, exposure/risk assessment, and manufacturer data. The major issues in the literature were the demonstrations that increasing temperature and applying forces increased permeation; and that glove manufacturer data were sometimes not reproducible. Double gloving of disposable gloves was found to be effective in resisting chemical permeation for short periods of time. Harmonization of standards and commercial glove classifications were called for at conditions that were closer to the temperature and applied forces actually present in the workplace, including whole glove testing and quantitative rather than just qualitative criteria. More research was recommended in each section and subsection with particular emphasis on defining the efficiency of solid phase collection devices, and more data in areas like exposure to cosmetics, household products, liquid foods, drinks, and cleaning liquids. More research in exposure assessment for permeated chemicals with sensors on the inner glove surface and on the skin was called for. Finally, it was decided that the state of the art of current practice was in a situation that needed the permeation standards, research, and the permeation charts of glove manufacturers to be at conditions that better reflected those encountered by workers with donned gloves.


Asunto(s)
Guantes Protectores , Exposición Profesional/prevención & control , Humanos , Modelos Teóricos , Permeabilidad , Temperatura de Transición
3.
J Occup Environ Hyg ; 14(4): 243-251, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27754775

RESUMEN

The aim was to develop a whole glove permeation method for cyclohexanol to generate permeation parameter data for a non-moving dextrous robot hand (normalized breakthrough time tb, standardized breakthrough time ts, steady state permeation rate Ps, and diffusion coefficient D). Four types of disposable powderless, unsupported, and unlined nitrile gloves from the same producer were investigated: Safeskin Blue and Kimtech Science Blue, Purple, and Sterling. The whole glove method developed involved a peristaltic pump for water circulation through chemically resistant Viton tubing to continually wash the inner surface of the test glove via holes in the tubing, a dextrous robot hand operated by a microprocessor, a chemically protective nitrile glove to protect the robot hand, an incubator to maintain 35°C temperature, and a hot plate to maintain 35°C at the sampling point of the circulating water. Aliquots of 1.0 mL were sampled at regular time intervals for the first 60 min followed by removal of 0.5 mL aliquots every hour to 8 hr. Quantification was by the internal standard method after gas chromatography-selective ion electron impact mass spectrometry using a non-polar capillary column. The individual glove values of tb and ts differed for the ASTM closed loop method except for Safeskin Blue, but did not for the whole glove method. Most of the kinetic parameters agreed within an order of magnitude for the two techniques. The order of most protective to least protective glove was Blue and Safeskin, then Purple followed by Sterling for the whole gloves. The analogous order for the modified F739 ASTM closed loop method was: Safeskin, Blue, Purple, and Sterling, almost the same as for the whole glove. The Sterling glove was "not recommended" from the modified ASTM data, and was "poor" from the whole glove data.


Asunto(s)
Ciclohexanoles/química , Guantes Protectores , Ensayo de Materiales/métodos , Ciclohexanoles/análisis , Cromatografía de Gases y Espectrometría de Masas , Mano , Humanos , Nitrilos/química , Permeabilidad , Robótica
4.
J Occup Environ Hyg ; 14(4): 252-257, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27754818

RESUMEN

The differences in permeation parameters when a gloved dextrous robot hand clenched and did not were investigated with the dynamic permeation system described in the companion paper. Increased permeation through the gloves of the present study for cyclohexanol when the gloved hand clenched depended on glove thickness and porosity for cyclohexanol permeation. The Sterling glove, the thinnest and most porous, was the least protective. Hand clenching promoted more permeation for the Sterling glove in terms of breakthrough times, steady state permeation rate, and diffusion coefficient. The Safeskin glove showed increased permeation only for the steady state permeation rate but not breakthrough times or diffusion coefficient. The Blue and Purple gloves showed no differences when the hand was clenching or not. The correlational analysis supported differences between the clenching and non-clenching situations, and the risk assessment considered the worst and best scenarios relative to one and two hydrated hands that were and were not protected by specific gloves.


Asunto(s)
Ciclohexanoles/química , Guantes Protectores , Ensayo de Materiales/métodos , Ciclohexanoles/análisis , Cromatografía de Gases y Espectrometría de Masas , Mano , Humanos , Nitrilos/química , Permeabilidad , Robótica
5.
Proc Natl Acad Sci U S A ; 106(31): 12623-8, 2009 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-19620728

RESUMEN

The long-standing controversy regarding the late Pleistocene megafaunal extinctions in North America has been invigorated by a hypothesis implicating a cosmic impact at the Allerød-Younger Dryas boundary or YDB (approximately 12,900 +/- 100 cal BP or 10,900 +/- 100 (14)C years). Abrupt ecosystem disruption caused by this event may have triggered the megafaunal extinctions, along with reductions in other animal populations, including humans. The hypothesis remains controversial due to absence of shocked minerals, tektites, and impact craters. Here, we report the presence of shock-synthesized hexagonal nanodiamonds (lonsdaleite) in YDB sediments dating to approximately 12,950 +/- 50 cal BP at Arlington Canyon, Santa Rosa Island, California. Lonsdaleite is known on Earth only in meteorites and impact craters, and its presence strongly supports a cosmic impact event, further strengthened by its co-occurrence with other nanometer-sized diamond polymorphs (n-diamonds and cubics). These shock-synthesized diamonds are also associated with proxies indicating major biomass burning (charcoal, carbon spherules, and soot). This biomass burning at the Younger Dryas (YD) onset is regional in extent, based on evidence from adjacent Santa Barbara Basin and coeval with broader continent-wide biomass burning. Biomass burning also coincides with abrupt sediment mass wasting and ecological disruption and the last known occurrence of pygmy mammoths (Mammuthus exilis) on the Channel Islands, correlating with broader animal extinctions throughout North America. The only previously known co-occurrence of nanodiamonds, soot, and extinction is the Cretaceous-Tertiary (K/T) impact layer. These data are consistent with abrupt ecosystem change and megafaunal extinction possibly triggered by a cosmic impact over North America at approximately 12,900 +/- 100 cal BP.


Asunto(s)
Biomasa , Diamante , Extinción Biológica , Sedimentos Geológicos , Ecosistema , Microscopía Electrónica de Transmisión
6.
Arch Environ Contam Toxicol ; 58(2): 249-54, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19855916

RESUMEN

The aim of this study was to measure permeation of the herbicide dichlobenil in Casoron 4G through disposable and chemically protective nitrile gloves using an American Society for Testing and Materials-type permeation cell and a closed-loop system employing two different solvents (hexane and water) and two different challenge situations (aqueous emulsion and solid formulation). Capillary gas chromatography-mass spectrometry was used for quantification purposes. The chemically protective glove did not allow any permeation up to 8 h for the solid-formulation and water-collection challenges, but permeation was detected in all other challenges. The disposable glove allowed the most permeation, and the solid-formulation challenge with water collection necessitated that a dichlobenil equivalent be calculated because of the presence of its hydrolysis degradation product 2,6-dichlorobenzamide. Permeation from the solid formulation was detectable by hexane collection for both the disposable and chemically protective gloves and by water collection for the disposable glove. It was concluded that hexane-solvent collection was not valid for the disposable glove at 4 and 8 h of permeation in the solid Casoron challenge or for the aqueous emulsion challenge at 8 h relative to the water-collection solvent data. The hexane-solvent collection for the chemically protective glove was valid for the 8-h solid-formulation challenge but not for the 8-h aqueous-solution challenge. All water-solvent collections were valid; however, dichlobenil usually permeated the gloves.


Asunto(s)
Guantes Protectores , Herbicidas/química , Nitrilos/química , Benzamidas/química , Equipos Desechables , Estabilidad de Medicamentos , Cromatografía de Gases y Espectrometría de Masas , Herbicidas/análisis , Hexanos/química , Hidrólisis , Nitrilos/análisis , Permeabilidad , Solubilidad , Solventes/química , Factores de Tiempo , Agua/química
7.
Bull Environ Contam Toxicol ; 84(1): 5-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19784533

RESUMEN

Whole glove testing for a metalworking fluid (MWF) in the field was performed for the first time. Green latex gloves used in a machine shop were exposed for 20 min to MWF. The permeated amount (1.0 +/- 0.5 microg/cm(2)) was higher than the threshold (0.25 microg/cm(2)) for the ASTM F739-99a closed-loop normalized breakthrough time.


Asunto(s)
Contaminantes Ambientales/química , Guantes Protectores , Metalurgia , Exposición Profesional , Análisis de Falla de Equipo , Humanos , Permeabilidad
8.
J Hazard Mater ; 151(2-3): 692-8, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-17662521

RESUMEN

The influence of collection solvents hexane and perfluorohexane on the permeation of the non-polar and non-volatile di-n-octyl disulfide (DOD) through nitrile glove material was investigated using the American Society for Testing and Materials (ASTM) F739-99a method. The weight and the thickness of the nitrile material increased about 6%, statistically significant at p

Asunto(s)
Ácidos Alcanesulfónicos/química , Fluorocarburos/química , Guantes Protectores , Nitrilos/química , Solventes/química , Cromatografía de Gases/métodos , Diseño de Equipo , Fluorocarburos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Sustancias Peligrosas , Espectrometría de Masas/métodos , Ensayo de Materiales , Modelos Estadísticos , Exposición Profesional , Ropa de Protección , Factores de Tiempo
9.
Appl Spectrosc ; 61(2): 204-11, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17331313

RESUMEN

The aim of this study was to investigate the surface variability of 13 powder-free, unlined, and unsupported nitrile rubber gloves using attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectrophotometry at key wavelengths for analysis of captan contamination. The within-glove, within-lot, and between-lot variability was measured at 740, 1124, 1252, and 1735 cm(-1), the characteristic captan reflectance minima wavelengths. Three glove brands were assessed after conditioning overnight at relative humidity (RH) values ranging from 2 +/- 1 to 87 +/- 4% and temperatures ranging from -8.6 +/- 0.7 to 59.2 +/- 0.9 degrees C. For all gloves, 1735 cm(-1) provided the lowest background absorbance and greatest potential sensitivity for captan analysis on the outer glove surface: absorbances ranged from 0.0074 +/- 0.0005 (Microflex) to 0.0195 +/- 0.0024 (SafeSkin); average within-glove coefficients of variation (CV) ranged from 2.7% (Best, range 0.9-5.3%) to 10% (SafeSkin, 1.2-17%); within-glove CVs greater than 10% were for one brand (SafeSkin); within-lot CVs ranged from 2.8% (Best N-Dex) to 28% (SafeSkin Blue); and between-lot variation was statistically significant (p < or = 0.05) for all but two SafeSkin lots. The RH had variable effects dependent on wavelength, being minimal at 1735, 1252, and 1124 cm(-1) and highest at 3430 cm(-1) (O-H stretch region). There was no significant effect of temperature conditioning. Substantial within-glove, within-lot, and between-lot variability was observed. Thus, surface analysis using ATR-FT-IR must treat glove brands and lots as different. ATR-FT-IR proved to be a useful real-time analytical tool for measuring glove variability, detecting surface humidity effects, and choosing selective and sensitive wavelengths for analysis of nonvolatile surface contaminants.


Asunto(s)
Captano/análisis , Elastómeros/química , Fungicidas Industriales/análisis , Guantes Protectores , Nitrilos/química , Humedad , Indicadores y Reactivos , Espectrofotometría Infrarroja , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
10.
J Hazard Mater ; 147(3): 923-9, 2007 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-17324502

RESUMEN

The aim was to investigate the permeation of a straight oil metalworking fluid (MWF) through four types of glove materials using the gravimetric method and the modified American Society for Testing and Materials (ASTM) F739-99a method with perfluorohexane and hexane as collection solvents. The residual masses on the collection side were determined after solvent evaporation for both MWF and blank (air) challenges. With perfluorohexane, the permeated MWF through gloves after 8h was around the lower quantifiable limit for nitrile, 0.7+/-0.2mg/cm(2) for vinyl, 10.0+/-1.2mg/cm(2) for chloroprene, and 33.0+/-0.7mg/cm(2) for latex. Hexane increased the amounts and rates of MWF permeating all gloves 39-73 times, except for vinyl where extractable mass was so high that the residues for MWF challenges and for hexane blanks were indistinguishable. Hexane as a collection solvent also extracted more glove components than did perfluorohexane, and back-permeated gloves in much larger amounts. Perfluorohexane allows better estimates of the real permeation rates and breakthrough times than does hexane. Recommendations based on breakthrough times and permeation rates with hexane collection are thus too conservative, although the relative ranking of these four types of gloves was the same with either collection solvent.


Asunto(s)
Cloropreno/química , Guantes Protectores , Látex/química , Aceite Mineral/química , Nitrilos/química , Exposición Profesional , Cloruro de Polivinilo/química , Permeabilidad , Solventes/química
11.
J Chromatogr A ; 1101(1-2): 25-31, 2006 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-16233901

RESUMEN

The aim of this study was to identify and quantify an unknown peak in the chromatogram of a very complex mixture, a straight oil metalworking fluid (MWF). The fraction that permeated through a thin nitrile polymer membrane had less mineral oil background than the original MWF did at the retention time of the unknown peak, thus facilitating identification by total ion current (TIC) gas chromatography-mass spectrometry (GC-MS). The peak proved to be di-n-octyl disulfide (DOD) through retention time and mass spectral comparisons. Quantitation of DOD was by extracted ion chromatogram analysis of the DOD molecular ion (mass-to-charge ratio (m/z) 290), and of the m/z 71 ion for the internal standard, n-triacontane. Linear models of the area ratio (y) of these two ions versus DOD concentration showed a systematic negative bias at low concentrations, a common occurrence in analysis. The linear model of y(0.8) (from Box-Cox power transformation) versus DOD concentration showed negligible bias from the lowest measured standard of 1.51 mg/L to the highest concentration tested at 75.5 mg/L. The intercept did not differ statistically from zero. The concentration of DOD in the MWF was then calculated to be 0.398+/-0.034% (w/w) by the internal standard method, and 0.387+/-0.036% (w/w) by the method of standard additions. These two results were not significantly different at p < or = 0.05. The Box-Cox transformation is therefore recommended when the data for standards are non-linear.


Asunto(s)
Ácidos Alcanesulfónicos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Metalurgia/métodos , Calibración , Interpretación Estadística de Datos
12.
J Hazard Mater ; 137(1): 165-71, 2006 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16713085

RESUMEN

The goal of the study was to assess how protective disposable (Safeskin) and chemical protective (Sol-Vex) nitrile gloves were against Comite emulsifiable concentrate formulation containing propargite (PROP) as active pesticidal ingredient, because there were no explicit recommendations for the gloves that should be worn for hand protection. The glove material was exposed in ASTM-type I-PTC-600 permeation cells at 30.0+/-0.5 degrees C, and gas chromatography-mass spectrometry used for PROP analysis. Aqueous solutions of Comite at 40.4 mg/mL permeated both Safeskin and Sol-Vex nitrile by 8h. Safeskin showed a mean PROP mass permeated of 176+/-27 microg after 8h compared with a mean mass permeated for Sol-Vex of 3.17+/-4.08 microg. Thus, Sol-Vex was about 56 times more protective than Safeskin for an 8-h exposure. However, the kinetics of the permeation revealed that Safeskin can be worn for at least 200 min before disposal. When undiluted Comite challenged both types of nitrile, much faster permeation was observed. Safeskin gloves showed two steady state periods. The first had lag times (t(l)) values of about 1h, although normalized breakthrough times (t(b)) were < 10 min. The second steady state rate (P(s)) was on average four times the rate of the first period, and the second steady state period t(l) was about three times as long as that of the first steady state period, and about the same t(l) as for the aqueous solution. Sol-Vex gloves exposed continuously to undiluted Comite permeated above the normalized breakthrough threshold beyond 2.7h. A risk assessment revealed that the PROP skin permeation rate of 7.1 ng cm(-2)h(-1) was much slower than the first steady state Safeskin glove P(s) of 62,000 ng cm(-2)h(-1). Infrared analysis showed that the glove surfaces were not degraded by the Comite challenge. The chemically protective Sol-Vex gloves protected adequately against undiluted formulation for about 2.7h, whereas they provided protection for nearly 8h when the formulation was diluted with water to the highest concentration for field application. In contrast, the disposable Safeskin gloves did not protect at all for the undiluted formulation, but did for 200 min when the formulation was diluted with water to the highest concentration for spraying.


Asunto(s)
Ciclohexanos/análisis , Ciclohexanos/química , Guantes Protectores , Nitrilos/análisis , Cromatografía de Gases , Sustancias Peligrosas , Espectrometría de Masas , Modelos Estadísticos , Riesgo , Espectrofotometría Infrarroja , Espectroscopía Infrarroja por Transformada de Fourier , Factores de Tiempo
13.
J Hazard Mater ; 137(2): 709-15, 2006 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-16650529

RESUMEN

The aim of the present study was to quantify the permeation parameters of a complex water-insoluble straight oil metalworking fluid (MWF) of low volatility through nitrile gloves. The permeation through a chemically protective and a disposable glove was investigated using the American Society for Testing and Materials (ASTM) F739-99a method with hexane as the collection medium. Analysis of collection side samples involved gas chromatography-mass spectrometry (GC-MS) and gravimetry. The detection breakthrough time for the chemically protective glove was >10 h. For the disposable glove, the detection breakthrough time was 0.7+/-0.3 h, the lag time was 1.6+/-0.1 h, the diffusion coefficient was (3.7+/-0.3)x10(-9) cm2/min, and the steady state permeation rate was 3.5+/-2.2 microg/cm2/min. The disposable nitrile glove can be worn for about 30 min for incidental contact with straight oil MWFs without known carcinogens. The chemically protective nitrile glove should be worn otherwise. The chromatogram for the permeate differed from that of the original MWF, resulting from the faster permeation of lower molecular weight congeners. The combination of chromatography and gravimetry allowed quantifying the permeation parameters of complex water-insoluble non-volatile mixtures.


Asunto(s)
Guantes Protectores , Aceite Mineral/química , Nitrilos/química , Aceites de Plantas/química , Cromatografía de Gases y Espectrometría de Masas , Permeabilidad
14.
Appl Spectrosc ; 59(6): 724-31, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16053538

RESUMEN

This study developed a method to produce uniform captan surface films on a disposable nitrile glove for quantitation with a portable attenuated total reflection Fourier transform infrared (ATR-FTIR) spectrometer. A permeation test was performed using aqueous captan formulation. Uniform captan surface films were produced using solvent casting with 2-propanol and a 25 mm filter holder connected to a vacuum manifold to control solvent evaporation. The coefficient of variation of the reflectance at 1735 +/- 5 cm(-1) was minimized by selection of the optimum solvent volume, airflow rate, and evaporation time. At room temperature, the lower to upper quantifiable limits were 0.31-20.7 microg/cm2 (r = 0.9967; p < or = 0.05) for the outer glove surface and 0.55-17.5 microg/cm2 (r = 0.9409; p < or = 0.05) for the inner surface. Relative humidity and temperature did not affect the uncoated gloves at the wavelength of captan analysis. Glove screening using ATR-FTIR was necessary as a control for between-glove variation. Captan permeation, after 8 hours exposure to an aqueous concentration of 217 mg/mL of Captan 50-WP, was detected at 0.8 +/- 0.3 microg/cm2 on the inner glove surface. ATR-FTIR can detect captan permeation and can determine the protectiveness of this glove in the field.


Asunto(s)
Algoritmos , Captano/análisis , Materiales Biocompatibles Revestidos/análisis , Análisis de Falla de Equipo/métodos , Guantes Protectores , Nitrilos/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Captano/química , Materiales Biocompatibles Revestidos/química , Ensayo de Materiales , Nitrilos/química , Permeabilidad
15.
J Hazard Mater ; 124(1-3): 81-7, 2005 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-15982807

RESUMEN

Telone is a potent fumigant that is based on the chlorinated unsaturated hydrocarbon, 1,3-dichloropropene (1,3-DCP). It is often applied without dilution and so poses severe inhalation and air pollution threats. Urinary metabolites of 1,3-DCP have been detected after Telone skin exposure, so that preventing dermal exposure is also important. The objective of the study was to assess if nitrile and multi-layer ("laminated") gloves provide adequate protection against Telone EC formulation. To accomplish this, disposable (Safeskin) and chemically resistant (Sol-Vex) nitrile and laminated (Barrier mark and Silver Shield) glove materials were challenged by Telone EC with hexane liquid collection in an ASTM-type I-PTC-600 permeation cell. Analyses of cis- and trans-1,3-DCP in the collection fluid at specified times were performed on a moderately polar capillary column by gas chromatography-electron capture detection. Telone EC caused microholes in both nitrile materials, though the chemically protective material was degraded slower than the disposable nitrile. The laminated gloves offered limited protection. Silver Shield protected best because 1.5-2.3 mg 1,3-DCP permeated by 8 h relative to 2.5-7.6 mg for Barrier, implying about 2.5 times more protection for 8 h. Even for Silver Shield, the extent of protection was inadequate as illustrated by a risk assessment of the skin exposure situation. The normalized breakthrough times for both types of laminated gloves varied between 27 and 60 min. It is recommended that Viton gloves still be worn for protection.


Asunto(s)
Compuestos Alílicos/química , Guantes Protectores , Animales , Modelos Animales de Enfermedad , Humanos , Hidrocarburos Clorados , Rayos Infrarrojos , Dosificación Letal Mediana , Ratones , Modelos Químicos , Nitrilos/química , Permeabilidad , Ratas , Absorción Cutánea
16.
Mutat Res ; 563(1): 13-24, 2004 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-15324745

RESUMEN

Formaldehyde (FA) is a mutagen that, at high concentrations and long durations, has been reported to cause nasal cancer in rats and in some humans. The level of FA-induced modified DNA in nasal cells should serve as a biomarker of FA exposure and effect. In the present study, a high-performance liquid chromatography (HPLC)-ultraviolet (UV) method at 254 nm was developed and optimized to detect and quantify hydroxymethyldeoxynucleosides after the isolated DNA in exposed human nasal epithelial cells (HNEC) was enzymically digested. Normal and modified deoxynucleosides were successfully resolved from one another and from tissue and enzyme blank interferences. The viability of HNEC exposed to FA in solution for 24 h decreased, and there was a linear dose response between % nonviability and FA dose from 10 to 500 microg/mL. Amounts of 18.0 +/- 1.5 pmol N6-dA and 12.0 +/- 1.2 pmol N2-dG derivatives were determined in a 10 microL injection after 1.4 x 10(7) HNEC (106 microg DNA) were exposed to 500 microg/mL in solution. The respective tissue concentrations in pmol hydroxymethyldeoxynucleoside/mg DNA were 170 +/- 14 and 113 +/- 11. The lower quantifiable limits were about 97 and 88 pmol/mg DNA, respectively. Diffusive exposure of HNEC to air FA up to 100 ppm (v/v) for 24 h did not produce quantifiable hydroxymethylnucleosides. FA-modified deoxynucleosides may be useful biomarkers for FA exposure in biological monitoring samples taken by nasal lavage or brush biopsy.


Asunto(s)
Aductos de ADN/análisis , Fijadores/metabolismo , Formaldehído/metabolismo , Mutágenos/metabolismo , Mucosa Nasal/metabolismo , Animales , Biomarcadores , Supervivencia Celular , Células Cultivadas , Cromatografía Líquida de Alta Presión/métodos , Exposición a Riesgos Ambientales , Fijadores/farmacología , Formaldehído/farmacología , Humanos , Masculino , Mucosa Nasal/citología , Mucosa Nasal/efectos de los fármacos , Neoplasias Nasales/inducido químicamente , Neoplasias Nasales/genética , Ratas
17.
J Hazard Mater ; 100(1-3): 95-107, 2003 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-12835015

RESUMEN

The purpose of this study was to investigate the permeation of an aqueous emulsion of the pesticide, captan, as a wettable powder (48.9% captan) through a disposable nitrile glove material using an American Society for Testing and Materials (ASTM)-type I-PTC-600 permeation cell. The goal was to investigate the protective capability of the gloves against dermatitis. The analytical method was based on gas chromatography-mass spectrometry (GC-MS) and gas chromatography-electron capture detection (GC-ECD). The least quantifiable limit (LQL) was 6 ng for GC-ECD and 30 ng for GC-MS. Testing was conducted using the ASTM F739 closed-loop permeation method and a worst-case aqueous concentration 217 mg/ml of captan 50-WP. The average permeation rates were low, with 12+/-5 ng/(cm(2)min) after 2h, 50+/-25 ng/(cm(2)min) after 4h, and 77+/-58 ng/(cm(2)min) after 8h. The calculated diffusion coefficient was (1.28+/-0.10) x 10(-5)cm(2)/h. No significant swelling or shrinkage occurred at P

Asunto(s)
Captano/química , Fungicidas Industriales/química , Guantes Protectores , Emulsiones , Cromatografía de Gases y Espectrometría de Masas , Ensayo de Materiales , Nitrilos , Permeabilidad
18.
Mar Pollut Bull ; 46(4): 424-9, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12705915

RESUMEN

Our aim was to assess whether past discharges from a wastewater treatment plant increased metal pollutant loads in stream mobile species in a one-day baseline sampling study that included a coastal wetland. Mosquitofish (Gambusia affinis) of two sizes, black bullhead (Ameiurus melas), and crayfish (Pacifastacus leniusculus) were collected from Malibu Creek, and California killifish (Fundulus parvipinnis) of three sizes, as well as arroyo chub (Gila orcutti) were sampled from Malibu Lagoon near Los Angeles, California. Species from each locality were pooled by length, homogenized, digested by microwave wet ashing, and analyzed by simultaneous inductively coupled plasma atomic emission spectroscopy for 27 elements. Lagoon killifish 2.0-3.5 cm long contained levels of arsenic and lead above the levels for 95% of California fish, the EDL95. Black bullhead upstream of the discharge contained elevated levels of As, Cr and Se. Young mosquitofish <3 cm in length upstream of the discharge differed greatly in the order of abundance of their elements relative to larger mosquitofish and to other species collected. More sampling than this baseline study allowed was needed to determine if the wastewater treatment plant was a pollution source.


Asunto(s)
Astacoidea , Peces , Contaminantes Químicos del Agua/análisis , Animales , Constitución Corporal , California , Ecosistema , Monitoreo del Ambiente , Eliminación de Residuos Líquidos , Movimientos del Agua , Contaminantes Químicos del Agua/farmacocinética
19.
J Hazard Mater ; 179(1-3): 57-62, 2010 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-20334969

RESUMEN

The aim was to measure the permeation of the fungicide chlorothalonil from Bravo Ultrex through disposable (Safeskin) and chemically protective (Solvex) nitrile glove materials in a closed-loop ASTM type permeation cell system employing different collection side solvents. The permeated fungicide was measured in the collection medium by the internal standard method through capillary gas chromatography-mass spectrometry and selective ion monitoring using m/z 222 (internal standard 4,4'-dichlorobiphenyl), and 224 and 226 (chlorothalonil). The permeated glove materials did not show swelling or shrinkage and infrared reflectance changes. Different permeated masses for the same glove material for aqueous emulsion challenges of 2.2 mg/mL Bravo Ultrex for 8 h were observed for different solvents with isopropanol>hexane>water for Safeskin, and isopropanol=hexane>water for Solvex. Solvex gloves always permeated less than Safeskin gloves for the same challenge time. When challenges with solid Bravo Ultrex occurred, chlorothalonil was still found in the collection side in the same solvent order as for the aqueous emulsion challenges, with Solvex always less than Safeskin for the same collection solvent and same challenge time. Kinetic experiments showed isopropanol was not a suitable collection solvent for Safeskin for 4 and 8 h. Hexane was not a valid collection solvent for Solvex and Safeskin for 8 h, but was better than isopropanol.


Asunto(s)
Fungicidas Industriales/química , Guantes Protectores , Nitrilos/química , Cromatografía de Gases y Espectrometría de Masas , Permeabilidad , Estándares de Referencia , Solubilidad , Solventes , Espectrofotometría Infrarroja , Agua
20.
Arch Environ Contam Toxicol ; 54(1): 1-8, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17680173

RESUMEN

The performance of protective gloves against metalworking fluids (MWFs) has rarely been studied because of the difficult chemical analysis associated with complex MWFs. In the present study, glove swelling was used as a screening parameter of glove compatibility after challenge of the outer surfaces of chloroprene, latex, nitrile, and vinyl disposable gloves by six MWF concentrates for 2 hours in an ASTM F-739-type permeation cell without collection medium. Swelling relative to original thickness was up to 39% for latex, 7.6% for chloroprene, and 3.5% for nitrile. Shrinking up to 9.3% occurred for vinyl. Chloroprene and latex did not swell significantly for the semisynthetic and synthetic MWFs. Vinyl, previously not tested, was a good candidate for MWFs other than the soluble oil type. Although nitrile was recommended by the National Institute for the Occupational Safety and Health (NIOSH) for all types of MWFs, its swelling after 2-hour challenge was significant with Student t-tests for the soluble oil, synthetic, and semisynthetic MWFs. Glove swelling can be used as a screening chemical degradation method for mixtures such as MWFs with difficult chemical analysis. Further studies need to be conducted on the relationship between permeation and glove swelling.


Asunto(s)
Guantes Protectores , Petróleo , Aceites de Plantas/química , Cloropreno , Látex , Metalurgia , Nitrilos , Permeabilidad , Cloruro de Polivinilo
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