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1.
Regul Toxicol Pharmacol ; 64(1): 35-42, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22683394

RESUMEN

A survey of selected mainstream smoke constituents from commercially marketed US cigarettes was conducted in 2009. The US cigarette market was segmented into thirteen (13) strata based on Cambridge Filter Method (CFM) "tar" category and cigarette design parameters. Menthol and non-menthol cigarettes were included. Sixty-one (61) cigarette brand styles were chosen to represent the market. Another thirty-four (34) brand styles of interest were included in the survey along with a Kentucky 3R4F reference cigarette. Twenty mainstream smoke constituents were evaluated using the Health Canada smoking regimen. By weighting the results of the 61 brand styles using the number of brand styles represented by each stratum, the mainstream smoke constituent means and medians of the US cigarette market were estimated. For nicotine, catechol, hydroquinone, benzo(a)pyrene and formaldehyde the mean yields increased with increasing "tar" yields. Constituent yields for the ultra-low "tar" and low "tar" cigarettes were not significantly different for most other analytes as ventilation blocking defeated any filter air dilution design features. In contrast, normalization per mg nicotine provided an inverse ranking of cigarette yields per CFM "tar" categories. Menthol cigarette mean constituent yields were observed to be within the range of the non-menthol cigarettes of similar "tar" categories.


Asunto(s)
Nicotiana/química , Humo/análisis , Contaminación por Humo de Tabaco/análisis , Recolección de Datos , Humanos , Breas/química , Estados Unidos
2.
J Chromatogr Sci ; 43(3): 133-40, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15842752

RESUMEN

The development and validation of a rapid liquid chromatography (LC)-tandem mass spectrometry (MS-MS) method for determination of nicotine and cotinine in smokers' serum is described. The method is based on solid-phase extraction in a 96-well plate format and requires only 100 microL of serum. Using normal-phase chromatography, both analytes elute in less than 1 min, which permits high sample throughput applications. The calibrated range is 2-100 ng/mL nicotine and 20-1,000 ng/mL cotinine. For known samples, recovery is 95-116% for nicotine and 93-94% for cotinine. The method is extended to rat serum and human saliva (cotinine only) using partial validation techniques. When compared with an existing radioimmunoassay method in our laboratory, the LC-MS-MS method gives improved accuracy, precision, and sample throughput.


Asunto(s)
Cromatografía Liquida/métodos , Cotinina/análisis , Espectrometría de Masas/métodos , Nicotina/análisis , Saliva/química , Fumar/metabolismo , Animales , Cotinina/sangre , Humanos , Nicotina/sangre , Control de Calidad , Radioinmunoensayo , Ratas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Fumar/sangre
4.
Analyst ; 125(7): 1295-8, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10984925

RESUMEN

A method for measuring amyl acetate in air was developed and validated. Known volumes of air samples from the output of an olfactometer, a device used to generate odor stimuli, were passed through charcoal sorbent tubes. Following extraction of the sorbent with carbon disulfide, the amount of amyl acetate collected on each tube was determined by gas chromatography with flame ionization detection. The method was used to determine the actual concentrations of amyl acetate presented to experimental participants in odor sensitivity testing.


Asunto(s)
Contaminantes Atmosféricos/análisis , Odorantes/análisis , Pentanoles/análisis , Calibración , Cromatografía de Gases
5.
Anal Chem ; 71(13): 480A-2A, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21649145

RESUMEN

A review of Practical Introduction to GS-MC Analysis with Quadrupoles.

6.
7.
J Clin Epidemiol ; 50(3): 253-63, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9120524

RESUMEN

Because of a lack of representative data on smoking status misclassification among U.S. married females, a two-part study was conducted. Part I was conducted to obtain nationally representative estimates of the percentage of U.S. women who report themselves to be current, former, and never smokers, to determine the concordance of smoking habits among spouse pairs, and to establish field quotas and probability weightings for Part II. Part II was conducted to determine smoker misclassification rates using salivary cotinine as an indication of active smoking. Part I, conducted in January 25-29, 1992, utilized random-digit dialing telephone interviewing throughout the 48 contiguous United States. Part II, conducted from February 19, 1992 to March 7, 1992, was a mall-intercept study in nine geographically disperse U.S. cities and it involved interviewing and saliva collection. Among married U.S. women, 25% reported they were current smokers, 22% reported they were former smokers, and 53% reported they were never smokers. Using a cotinine concentration of either > 35 ng/ml or > 106 ng/ml to indicate regular smoking, 3.61% and 2.55% of regular smokers, respectively, reported themselves to be never smokers. The concordance ratio, an important parameter in correcting for non-differential misclassification bias, was found to be 5.52. In addition, an indication of substantial differential misclassification was found between exposed and unexposed populations. This type of misclassification bias has previously not been accounted for in the adjustment of epidemiology-based risk assessments of tobacco smoke exposure and lung cancer. Taken together, these data suggest that misclassification bias alone is likely to explain any lung cancer risk elevation observed in the U.S. epidemiology of environmental tobacco smoke exposure among nonsmoking women.


Asunto(s)
Fumar/epidemiología , Esposos , Cotinina/análisis , Recolección de Datos , Femenino , Humanos , Incidencia , Saliva/química , Contaminación por Humo de Tabaco/estadística & datos numéricos , Estados Unidos/epidemiología
8.
JAMA ; 276(8): 603-4, 1996 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-8773626
9.
JAMA ; 275(6): 441; author reply 442, 1996 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-8627955
10.
Fundam Appl Toxicol ; 19(1): 133-40, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1397794

RESUMEN

Sprague-Dawley rats were exposed 6 hr per day for 14 consecutive days to aged and diluted sidestream smoke (ADSS), used as a surrogate for Environmental Tobacco Smoke (ETS), at concentrations of 0.1 (typical), 1 (extreme), or 10 (exaggerated) mg of particulates per cubic meter. Animals were exposed nose-only, inside whole-body chambers, to ADSS from the 1R4F reference cigarette. End-points included histopathology, CO-oximetry, plasma nicotine and cotinine, clinical pathology, and organ and body weights. The only pathological response observed was slight to mild epithelial hyperplasia and inflammation in the most rostral part of the nasal cavity, in the high-exposure group only. No effects were noted at medium or low exposures. The minimal changes noted were reversible, using a subgroup of animals kept without further treatment for an additional 14 days. Overall, the end-points used in the study demonstrated that there was no detectable biological activity of ADSS at typical or even 10-fold ETS concentrations and that the activity was only minimal at very exaggerated concentrations (particle concentrations 100 times higher than typical real-world concentrations).


Asunto(s)
Contaminación por Humo de Tabaco/efectos adversos , Administración por Inhalación , Animales , Relación Dosis-Respuesta a Droga , Femenino , Hemoglobinas/metabolismo , Masculino , Cavidad Nasal/efectos de los fármacos , Cavidad Nasal/patología , Necrosis , Nicotina/administración & dosificación , Nicotina/toxicidad , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
11.
J Assoc Off Anal Chem ; 72(6): 1002-6, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2592306

RESUMEN

A gas chromatographic method for determination of vapor phase nicotine in environmental tobacco smoke (ETS) was collaboratively studied by 6 laboratories. Nicotine is desorbed from XAD-4 sample tubes with ethyl acetate containing triethylamine and determined by gas chromatography with nitrogen-selective detection. Each collaborator received blind duplicate samples at each of 6 nicotine concentrations. Three concentrations were generated by spiking XAD-4 tubes with known amounts of nicotine; the remaining 3 concentrations were ETS samples obtained in a carefully controlled environmental chamber containing sidestream and exhaled mainstream smoke from 1R4F Kentucky reference cigarettes. Repeatability and reproducibility relative standard deviations ranged from 4.4 to 11.1% and from 7.0 to 11.1%, respectively, for nicotine concentrations evaluated (up to 6 micrograms/cu m). The method has been adopted official first action.


Asunto(s)
Nicotina/análisis , Contaminación por Humo de Tabaco/análisis , Cromatografía de Gases , Indicadores y Reactivos
12.
Analyst ; 114(9): 1005-8, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2610362

RESUMEN

A rapid gas chromatographic procedure with an analysis time of 5 min was developed for the determination of environmental nicotine collected on sorbent tubes containing XAD-4 resin. In validating this procedure, severe temporal losses of nicotine were observed for solutions in glass sample vials waiting in a queue in an autosampler tray for analysis. These losses were traced to adsorptive interactions of nicotine with the glass surface of the vials. The use of N-ethylnornicotine as the internal standard or the addition of triethylamine to all solutions were both successful in producing constant response ratios of nicotine to internal standard. Owing to the limited availability and expense of N-ethylnornicotine, our current procedure calls for the addition of triethylamine to all nicotine solutions at the 0.01% V/V level and the use of quinoline as internal standard.


Asunto(s)
Cromatografía de Gases , Nicotina/análisis , Contaminación por Humo de Tabaco/análisis , Adsorción
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