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1.
Tob Control ; 17 Suppl 1: i10-6, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18768454

RESUMEN

Of the chemicals identified to date in mainstream cigarette smoke with known toxicological properties, the volatile organic compounds (VOCs) are considered the most hazardous group owing to their high abundance and toxicity. In this research we evaluate a recently introduced line of cigarettes that contain charcoal in their filters. The amount of charcoal in these filters ranged from 45 mg to 180 mg and were either dispersed among the filter material or contained in a small cavity in the filter segment. Charcoal has long been used for removing VOCs from both water and air. Our findings indicate that these cigarettes reduce machine generated mainstream smoke deliveries of a wide range of VOCs compared to a similar, non-charcoal filtered, cigarette. However, this reduction is dependent not only on the amount of charcoal present but also on the volume of smoke being drawn through the filter. While a brand with 45 mg charcoal reduces VOC delivery under ISO smoking conditions, charcoal saturation and breakthrough occur under more intense smoking conditions. Breakthrough is minimised for brands with the most charcoal. Overall, the brands with the most charcoal are effective at reducing VOC deliveries under even intense smoking conditions.


Asunto(s)
Carbón Orgánico/química , Filtración/instrumentación , Nicotiana/química , Humo/análisis , Compuestos Orgánicos Volátiles/análisis , Seguridad de Productos para el Consumidor , Ensayo de Materiales/métodos , Nicotina/análisis , Fumar
2.
J Anal Toxicol ; 32(4): 281-91, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18430295

RESUMEN

The extent to which smokeless tobacco endangers human health is an ongoing subject of debate. Studies have shown that smokeless tobacco products contain high levels of biologically available nicotine and tobacco-specific nitrosamines. Toxic metals in smokeless tobacco products have been less extensively studied. In this study, concentrations of arsenic, barium, beryllium, cadmium, chromium, cobalt, lead, and nickel were measured in snuff products and iqmik tobacco, a product popular among some Alaska Natives. The average arsenic, cadmium, lead, and nickel concentrations in 17 commercially available brands were 0.23 +/- 0.06 microg/g, 1.40 +/- 0.31 microg/g, 0.45 +/- 0.13 microg/g and 2.28 +/- 0.36 microg/g, respectively. In 17 iqmik tobacco samples, the average arsenic, cadmium, lead, and nickel concentrations were 0.19 +/- 0.06 microg/g, 1.41 +/- 0.56 microg/g, 0.55 +/- 0.19 microg/g, and 2.32 +/- 1.63 microg/g, respectively. Using artificial saliva, the extractable levels of beryllium and lead were relatively low and consistent, whereas barium extracted from tobacco samples ranged from 2 to 21%. The group 1 and 2B carcinogens cadmium, cobalt, and nickel were more efficiently extracted by artificial saliva (30-65% of the cobalt, 20-46% of the nickel, and 21-47% of the cadmium).


Asunto(s)
Arsénico/análisis , Contaminantes Ambientales/análisis , Metales Pesados/análisis , Extractos Vegetales/química , Tabaco sin Humo/química , Saliva/química
3.
World Health Organ Tech Rep Ser ; (951): 1-277, 1 p following 277, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19522165

RESUMEN

This report presents the conclusions and recommendations of TobReg from its fourth meeting, where the Study Group deliberated on a number of topics in the field of tobacco product regulation and produced the following advisory notes and recommendations: an advisory note on smokeless tobacco products: health effects, implications for harm reduction and research needs; an advisory note on 'fire safer' cigarettes: approaches to reduced ignition propensity; a recommendation on mandated lowering of toxicants in cigarette smoke: tobacco-specific nitrosamines and selected other constituents; and a recommendation on cigarette machine smoking regimens. The four sections of this report address these four issues, and the Study Group's recommendations are set out at the end of each section. Its overall recommendations are summarized in section 5.


Asunto(s)
Investigación Biomédica/legislación & jurisprudencia , Fumar/efectos adversos , Fumar/legislación & jurisprudencia , Industria del Tabaco/legislación & jurisprudencia , Tabaco sin Humo/efectos adversos , Seguridad de Productos para el Consumidor/legislación & jurisprudencia , Salud Global , Regulación Gubernamental , Reducción del Daño , Humanos , Nicotina/toxicidad , Organización Mundial de la Salud
4.
Food Chem Toxicol ; 45(2): 202-9, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17011104

RESUMEN

Smoking remains the leading cause of preventable disease in the United States. Exposure to tobacco smoke leads to cancer, heart and lung disease, and addiction. The origin of the tobacco and cigarette manufacturing practices of counterfeit cigarettes are unknown. Because toxic metals are incorporated into the tobacco lamina during cultivation, the ambient metal content of the soil could produce significant differences in metal levels in both the tobacco and smoke of counterfeit cigarettes. We compared mainstream smoke cadmium, thallium, and lead deliveries from counterfeit and authentic brands. Mainstream smoke levels of all three metals were far greater for counterfeit than the authentic brands, in some cases by an order of magnitude. Significant differences still existed even after normalizing mainstream smoke metal levels with nicotine delivery; the counterfeits typically delivered much higher levels of all three analytes. Our findings, based on 21 different counterfeit samples, suggest that counterfeit cigarettes potentially result in a markedly greater exposure to toxic heavy metals than authentic brands, even after correcting for differences in nicotine intake. In view of the unknown health risks associated with inhaling higher levels of toxic metals, it is prudent to minimize exposure to toxic substances whenever possible.


Asunto(s)
Cadmio/análisis , Plomo/análisis , Nicotiana/química , Humo/análisis , Talio/análisis , Contaminación por Humo de Tabaco/análisis , Cadmio/aislamiento & purificación , Cromatografía de Gases , Contaminación Ambiental/análisis , Humanos , Plomo/aislamiento & purificación , Nicotina/análisis , Humo/efectos adversos , Fumar/efectos adversos , Talio/aislamiento & purificación , Volatilización
5.
Food Chem Toxicol ; 44(5): 714-23, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16309811

RESUMEN

The deliveries of cadmium, thallium, and lead in mainstream smoke particulate from cigarettes with different smoke delivery designs were determined by inductively coupled plasma-mass spectrometry in order to investigate their impact on the delivery of these known toxic compounds. Analyses showed that the levels of all three metals in smoke particulate were associated with their tar delivery category. After normalizing the metal concentrations to tar, there were no longer any statistically significant delivery differences between full-flavor, light or ultra-light cigarettes. When the concentrations were normalized to nicotine, the mean levels from the three delivery groups were much smaller than before normalization. But unlike the case using tar to normalize, in some of the cases, there were still some statistically significant differences in the nicotine-normalized results. These findings suggest that if smokers compensate for differences in nicotine intake, they receive exposures to toxic heavy metals from ultra-light, light and full-flavor cigarettes that are more similar than results would suggest from using the Federal Trade Commission method alone.


Asunto(s)
Cadmio/análisis , Plomo/análisis , Nicotiana/química , Humo/análisis , Breas/análisis , Talio/análisis , Humanos , Espectrometría de Masas , Fumar/efectos adversos , Contaminación por Humo de Tabaco/análisis , Volatilización
6.
Tob Control ; 13(1): 45-51, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14985595

RESUMEN

OBJECTIVE: Survey of nicotine, tar, and carbon monoxide (CO) smoke deliveries from 77 cigarette brands purchased in 35 countries was conducted using a standardised machine smoking method. The goal of this study was to determine regional variations and differences in the tar, nicotine, and CO smoke yields of a cigarette brand manufactured by a leading transnational corporation and of non-US locally popular cigarette brands. DESIGN: The majority of the cigarettes were purchased in each of the participating countries by delegate members of the World Health Organization and forwarded to the Centers for Disease Control and Prevention for analysis. Smoke deliveries were determined using a standardised smoking machine method and subsequent gravimetric and gas chromatography analysis. RESULTS: The smoke deliveries varied widely. Mainstream smoke deliveries varied from 6.8 to 21.6 mg tar/cigarette, 0.5 to 1.6 mg nicotine/cigarette, and 5.9 to 17.4 mg CO/cigarette. In addition to the smoke deliveries, the cigarettes were examined to determine physical parameters such as filter composition, length, and ventilation levels. CONCLUSION: Analysis of the smoke deliveries suggested that cigarettes from the Eastern Mediterranean, Southeast Asia, and Western Pacific WHO regions tended to have higher tar, nicotine, and CO smoke deliveries than did brands from the European, American, or African WHO regions surveyed.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monóxido de Carbono/análisis , Nicotiana , Nicotina/análisis , Humo/análisis , Breas/análisis
7.
Food Chem Toxicol ; 41(2): 303-17, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12480305

RESUMEN

Indian-made bidi cigarettes sold in the United States are available in a variety of exotic (e.g. clove, mango) and candy-like (e.g. chocolate, raspberry) flavors. Because certain tobacco flavorings contain alkenylbenzenes and other toxic or carcinogenic chemicals, we measured the concentration of flavor-related compounds in bidi tobacco using a previously developed method. Twenty-three brands of bidis were sampled using automated headspace solid-phase microextraction and subsequently analyzed for 12 compounds by gas chromatography-mass spectrometry. Two alkenylbenzene compounds, trans-anethole and eugenol, were found in greater than 90% of the brands analyzed. Methyleugenol, pulegone and estragole were each detected in 30% or more of the brands, whereas safrole and elemicin were not detected in any of the brands. The flavor-related compounds with the highest tobacco concentrations were eugenol (12,000 microg/g tobacco) and trans-anethole (2200 microg/g tobacco). The highest eugenol and trans-anethole concentrations found in bidi tobacco were about 70,000 and 7500 times greater, respectively, than the highest levels previously found in US cigarette brands. Measurement of these compounds is crucial to evaluation of potential risks associated with inhaling highly concentrated flavor-related compounds from bidis or other tobacco products.


Asunto(s)
Anisoles/análisis , Benzaldehídos/análisis , Cumarinas/análisis , Eugenol/análisis , Monoterpenos/análisis , Nicotiana/química , Derivados de Alilbenceno , Benzodioxoles , Monoterpenos Ciclohexánicos , Aromatizantes/análisis , Cromatografía de Gases y Espectrometría de Masas , India
8.
Intern Med J ; 32(7): 346-8, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12088355

RESUMEN

A transient deterioration in neurological status following commencement of chemotherapy for high-grade gliomas has not been previously described. We report eight cases of transient deterioration following administration of temozolomide, a relatively new cytotoxic agent used in the treatment of high-grade gliomas. We believe this represents the novel clinical entity of temozolomide-induced tumour flare.


Asunto(s)
Antineoplásicos Alquilantes/efectos adversos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Dacarbazina/análogos & derivados , Dacarbazina/efectos adversos , Glioma/tratamiento farmacológico , Glioma/patología , Adulto , Anciano , Antineoplásicos Alquilantes/administración & dosificación , Astrocitoma/tratamiento farmacológico , Astrocitoma/patología , Neoplasias Encefálicas/fisiopatología , Dacarbazina/administración & dosificación , Femenino , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Glioma/fisiopatología , Humanos , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Temozolomida
9.
J Clin Neurosci ; 8(4): 325-7, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11437571

RESUMEN

Temozolomide has an evolving role in the treatment of high grade gliomas. Recent studies suggest that temozolomide is well tolerated and efficacious. This study retrospectively analysed the activity and toxicity associated with temozolomide at two Australian centres over a 24 month period. Fifty-six patients with recurrent high grade gliomas were treated with temozolomide. Patients received temozolomide orally at 150-200mg/m(2)daily, days 1-5, every 4 weeks. The median number of treatment cycles was 4 (1-12). Of the 56 patients, 15 (27%) achieved complete or partial response and 18 (32%) achieved minor response or stable disease. There were no episodes of febrile neutropenia and temozolomide was generally well tolerated. In conclusion, temozolomide is an active therapy in patients with recurrent high grade glioma and our results concord with published studies.


Asunto(s)
Antineoplásicos Alquilantes/administración & dosificación , Antineoplásicos Alquilantes/efectos adversos , Neoplasias Encefálicas/tratamiento farmacológico , Dacarbazina/administración & dosificación , Dacarbazina/efectos adversos , Glioma/tratamiento farmacológico , Adulto , Anciano , Australia , Neoplasias Encefálicas/mortalidad , Dacarbazina/análogos & derivados , Supervivencia sin Enfermedad , Femenino , Glioma/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Temozolomida , Resultado del Tratamiento
10.
Arch Environ Health ; 56(2): 157-66, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11339680

RESUMEN

Little is known about factors that influence blood levels of volatile organic compounds in nonoccupationally exposed populations. The authors examined the possible relationship between recent self-reported chemical exposures and elevated blood volatile organic compound levels among 982 adult participants in theThird National Health and Nutrition Examination Survey. A strong dose-response effect was indicated (p < .001) for increasing lifetime pack-years of cigarettes smoked for elevated levels of toluene, styrene, and benzene. A positive dose-response effect was indicated for daily alcohol consumption with respect to elevated blood levels of 2-butanone and acetone. For volatile organic compounds typically found in 10-75% of the population, the establishment of a link with specific environmental exposures is relatively easy because there is less effect of confounding in this group. Some volatile organic compounds, however, are seen in less than 10% of the general population; finding these compounds at any level may warrant a search for a particular exposure.


Asunto(s)
Exposición a Riesgos Ambientales , Hidrocarburos Clorados/sangre , Vigilancia de la Población , Adulto , Etnicidad , Femenino , Humanos , Renta , Modelos Logísticos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Factores de Riesgo , Fumar/efectos adversos , Estados Unidos , Población Urbana
11.
J Expo Anal Environ Epidemiol ; 10(4): 321-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10981726

RESUMEN

Exposure to drinking water disinfection by-products (DBPs), such as trihalomethanes (THMs), has been associated with bladder and colorectal cancer in humans. Exposure to DBPs has typically been determined by examining historical water treatment records and reconstructing study participants' water consumption histories. However, other exposure routes, such as dermal absorption and inhalation, may be important components of an individual's total exposure to drinking water DBPs. In this study, we examined individuals' exposure to THMs through drinking, showering, or bathing in tap water. Thirty-one adult volunteers showered with tap water for 10 min (n = 11), bathed for 10 min in a bathtub filled with tap water (n = 10), or drank 1 l of tap water during a 10 min time period (n = 10). Participants provided three 10 ml blood samples: one sample immediately before the exposure; one sample 10 min after the exposure ended; and one sample 30 min (for shower and tub exposure) or 1 h ( for ingestion) after the exposure ended. A sample of the water (from the tap, from the bath, or from the shower) was collected for each participant. We analyzed water samples and whole blood for THMs (bromoform, bromodichloromethane, dibromochloromethane, and chloroform) using a purge-and-trap/gas chromatography/mass spectrometry method with detection limits in the parts-per-quadrillion range. The highest levels of THMs were found in the blood samples from people who took 10 min showers, whereas the lowest levels were found in the blood samples from people who drank 1 l of water in 10 min. The results from this study indicate that household activities such as bathing and showering are important routes for human exposure to THMs.


Asunto(s)
Desinfectantes/análisis , Exposición a Riesgos Ambientales/análisis , Trihalometanos/análisis , Abastecimiento de Agua , Adulto , Desinfectantes/efectos adversos , Conducta de Ingestión de Líquido , Femenino , Humanos , Higiene , Masculino , Trihalometanos/efectos adversos
12.
J Chromatogr Sci ; 38(4): 137-44, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10766479

RESUMEN

A method incorporating solid-phase microextraction (SPME) and gas chromatography-mass spectrometry for the headspace analysis of selected volatile organic compounds present in cigarette tobacco is developed and evaluated. Quantitative information on methyl, ethyl, n-propyl, isopropyl, isopropenyl, vinyl, and butyl acetates present in 29 different flavor variants (full, light, and ultra-light) of the top ten selling brands in the United States is presented. The concentrations of the various acetate analytes range from the low nanaogram to microgram levels per cigarette. Clear differences are observed in the concentrations of various acetates when comparing the levels in brands from different manufacturers. The SPME technique provides a method that allows high sample throughput, requires little sample preparation, and yields useful analytical information. High precision is obtained on multiple measurements of cigarettes from an individual pack, but lower precision levels are observed in general when comparing results obtained on the analysis of cigarettes from different packs of the same brand. The higher pack-to-pack variations may be due in part to product aging with a proportionate amount of evaporative loss of the relatively volatile acetates.


Asunto(s)
Acetatos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Nicotiana/química , Plantas Tóxicas , Calibración , Compuestos Orgánicos/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Volatilización
13.
J Agric Food Chem ; 48(4): 1298-306, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10775389

RESUMEN

Little is known about the possible health effects associated with inhaling alkenylbenzenes through cigarette smoking, even though these flavor-related compounds have known toxic effects in animals. We developed a rapid and sensitive solid-phase extraction (SPE) method to quantify seven alkenylbenzenes and piperonal in mainstream cigarette smoke particulate. The smoke particulate fraction of a single cigarette was collected on Cambridge filter pads, solvent extracted, concentrated, purified with SPE, and analyzed by selected ion monitoring gas chromatography-mass spectrometry. We positively identified and quantified five alkenylbenzenes compounds (eugenol, isoeugenol, methyleugenol myristicin, and elemicin) and piperonal in the smoke particulate from eight U.S. brands with mean levels (measured in triplicate) ranging from 6.6 to 4210 ng per cigarette. Additionally, complete blocking of nearly invisible ventilation holes in the cigarette filter increased 2- to 7-fold the percent transfer of alkenylbenzenes from tobacco to the particulate fraction of mainstream smoke.


Asunto(s)
Alquenos/análisis , Derivados del Benceno/análisis , Compuestos de Bencilo , Nicotiana , Plantas Tóxicas , Humo/análisis , Derivados de Alilbenceno , Benzaldehídos/análisis , Benzodioxoles , Dioxolanos/análisis , Eugenol/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Pirogalol/análogos & derivados , Pirogalol/análisis , Safrol/análisis , Gusto
14.
J Chromatogr Sci ; 38(2): 49-54, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10677832

RESUMEN

The analysis of volatile organic compounds (VOCs) in whole human blood at the low parts-per-trillion level has until recently required the use of a high-resolution mass spectrometer to obtain the specificity and detection limits required for epidemiological studies of VOC exposure in the general public. Because of the expense and expertise required to operate and maintain a high-resolution instrument, the applicability of this method has been limited. These limitations are overcome in a new method using automated headspace solid-phase microextraction (SPME) in conjunction with a gas chromatograph and a benchtop quadrupole mass spectrometer. A combination of SPME and multiple single-ion monitoring minimizes the interferences and chemical noise associated with whole blood samples. This method permits the analysis of 10 VOCs in human blood while simplifying the sample preparation and reducing the possible exposure of the analyst to blood aerosols. Twelve samples can be run successively in a fully automated mode, thus eliminating the need for operator attention. Detection limits are below 50 ppt (pg/mL) for a majority of the VOCs tested with a 5-mL sample.


Asunto(s)
Compuestos Orgánicos/sangre , Calibración , Humanos , Indicadores y Reactivos , Espectrometría de Masas , Estándares de Referencia
15.
N Engl J Med ; 342(2): 96-100, 2000 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-10631279

RESUMEN

BACKGROUND AND METHODS: Mass psychogenic illness may be difficult to differentiate from illness caused by bioterrorism, rapidly spreading infection, or toxic substances. We investigated symptoms attributed to exposure to toxic gas at a high school in Tennessee. In November 1998, a teacher noticed a 'gasoline-like' smell in her classroom, and soon thereafter she had a headache, nausea, shortness of breath, and dizziness. The school was evacuated, and 80 students and 19 staff members went to the emergency room at the local hospital; 38 persons were hospitalized overnight. Five days later, after the school had reopened, another 71 persons went to the emergency room. An extensive investigation was performed by several government agencies. RESULTS: We were unable to find a medical or environmental explanation for the reported illnesses. The persons who reported symptoms on the first day came from 36 classrooms scattered throughout the school. The most frequent symptoms (in this group and the group of people who reported symptoms five days later) were headache, dizziness, nausea, and drowsiness. Blood and urine specimens showed no evidence of carbon monoxide, volatile organic compounds, pesticides, polychlorinated biphenyls, paraquat, or mercury. There was no evidence of toxic compounds in the environment. A questionnaire administered a month later showed that the reported symptoms were significantly associated with female sex, seeing another ill person, knowing that a classmate was ill, and reporting an unusual odor at the school. CONCLUSIONS: The illness attributed to toxic exposure had features of mass psychogenic illness - notably, widespread subjective symptoms thought to be associated with environmental exposure to a toxic substance in the absence of objective evidence of an environmental cause. Alleviation of the anxiety surrounding an episode of mass psychogenic illness requires prompt recognition and a detailed investigation.


Asunto(s)
Brotes de Enfermedades , Exposición a Riesgos Ambientales/efectos adversos , Sustancias Peligrosas/análisis , Conducta de Masa , Trastornos Psicofisiológicos/epidemiología , Brotes de Enfermedades/economía , Exposición a Riesgos Ambientales/análisis , Femenino , Gasolina , Sustancias Peligrosas/efectos adversos , Humanos , Masculino , Odorantes , Trastornos Psicofisiológicos/economía , Trastornos Psicofisiológicos/etiología , Instituciones Académicas , Factores Sexuales , Tennessee/epidemiología
16.
J Chromatogr A ; 858(1): 79-89, 1999 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-10544893

RESUMEN

Some constituents found in natural flavorings are known to exhibit toxic properties. We developed a rapid method for quantifying 12 flavor-related compounds in cigarette tobacco using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry. Using selected ion monitoring, we quantified and positively identified coumarin; pulegone; piperonal and nine alkenylbenzenes, including trans-anethole, safrole, methyleugenol and myristicin in one or more brands of cigarettes. In 62% of 68 brands analyzed, we detected one or more of the flavor-related compounds ranging from 0.0018 to 43 microg/g. Toxic properties of these flavor-related compounds may constitute an additional health risk related to cigarette smoking.


Asunto(s)
Derivados del Benceno/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas/métodos , Nicotiana/química , Plantas Tóxicas , Calibración , Sensibilidad y Especificidad
17.
J Expo Anal Environ Epidemiol ; 9(4): 336-42, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10489158

RESUMEN

N-acetyl-S-(2-hydroxyethyl)-L-cysteine (2-hydroxyethyl mercapturic acid, HEMA) is a urinary metabolite of several hazardous chemicals, including vinyl chloride (VC), ethylene oxide (EO), and ethylene dibromide (EDB). Information about the levels of HEMA in the general population is useful for assessing human exposures to HEMA parent compounds, including VC, EO, and EDB. To establish reference range concentrations for HEMA, we analyzed urine samples from 412 adult participants in the Third National Health and Nutrition Examination Survey (NHANES II) by using isotope-dilution high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). HEMA was detected in 71% of the samples examined. Creatinine-corrected concentrations ranged from less than 0.68 microg/g creatinine to 58.7 microg/g creatinine; the 95th percentile concentration was 11.2 microg/g creatinine; and the geometric mean and median creatinine-corrected concentrations were both 1.6 microg/g creatinine. We observed a statistically significant difference (P=0.0001) in the creatinine-corrected geometric mean concentration values of HEMA between smokers (2.8 microg/g creatinine) and nonsmokers (1.1 microg/g creatinine). The high levels of HEMA seen among smokers likely originated from HEMA-producing chemicals known to be present in tobacco smoke.


Asunto(s)
Acetilcisteína/análogos & derivados , Carcinógenos/análisis , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/métodos , Dibromuro de Etileno/análisis , Óxido de Etileno/análisis , Cloruro de Vinilo/análisis , Acetilcisteína/orina , Adulto , Carcinógenos/metabolismo , Factores de Confusión Epidemiológicos , Dibromuro de Etileno/metabolismo , Óxido de Etileno/metabolismo , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Valores de Referencia , Análisis de Regresión , Reproducibilidad de los Resultados , Características de la Residencia , Fumar/orina , Estados Unidos , Cloruro de Vinilo/metabolismo
18.
Anal Chem ; 71(7): 1303-8, 1999 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-10204036

RESUMEN

A method for measuring four tobacco-specific nitrosamines (TSNAs), an important group of compounds in tobacco products, was developed. These compounds were extracted using supercritical fluid extraction (SFE) and purified by a sodium hydroxide wash of the ethyl acetate eluting solvent and solid-phase extraction. Quantitation was performed using gas chromatography/mass spectrometry (GC/MS). Spiking experiments were carried out to determine the recovery, precision, and limits of detection of this method. The detection limits were 0.04 microgram per sample for N'-nitrosonornicotine and N'-nitrosoanatabine and 0.02 microgram for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and N'-nitrosoanabasine. This method was used to measure TSNAs in various brands of cigarette tobacco with excellent reproducibility. The variation of TSNA levels among the cigarettes of different packs and types was significantly smaller than that among different brands. Comparable TSNA levels were obtained with SFE and liquid extraction methods. Signal-to-noise levels were similar for GC/MS and GC/thermal energy analysis when low-level tobacco samples were analyzed.


Asunto(s)
Nicotiana/química , Nitrosaminas/análisis , Plantas Tóxicas , Cromatografía de Gases y Espectrometría de Masas , Indicadores y Reactivos , Nitrosaminas/aislamiento & purificación
19.
Toxicol Ind Health ; 15(1-2): 168-79, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10188199

RESUMEN

Pesticides are used on a massive scale in the United States. The widespread use of these pesticides has made it virtually impossible for the average person to avoid exposure at some level. Generally, it is believed that low-level exposure to these pesticides does not produce acute toxic effects; however, various cancers and other noncancer health endpoints have been associated with chronic exposure to several groups of pesticides. Therefore, it is imperative that well-designed studies investigate the potential relationship between contemporary pesticide exposure and health effects. For these studies to be accurate, reliable methods for determining individual exposure must be used. Biological monitoring is a useful tool for assessing exposure to some contemporary pesticides. As with any analytical method, biological monitoring entails many difficulties, but, in many instances, they can be overcome by the logical use of available information and information acquired in carefully designed studies. At the Centers for Disease Control and Prevention (CDC), we have acquired extensive experience in the development and application of specific techniques for biological monitoring of a variety of toxicants, including many of the contemporary-use pesticides. We have used these methods to measure the internal dose of pesticides received by people in acute and chronic incidents resulting from both environmental and industrial exposure. Additionally, we have established normative values, or reference ranges, of several pesticides based on measurements of their metabolites in the urine of randomly selected adults in the US population. These data have been successfully used to distinguish overt exposures from 'background' exposure. In this paper, we present several examples of the usefulness of biological monitoring in urine and blood and describe the difficulties involved with developing methods in these matrices. We also present a general strategy, considerations, and recommendations for developing biological monitoring techniques for measuring the internal dose of contemporary-use pesticides.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/métodos , Plaguicidas/efectos adversos , Adulto , Humanos , Exposición Profesional , Plaguicidas/análisis , Plaguicidas/farmacología , Valores de Referencia , Medición de Riesgo
20.
J Chromatogr A ; 814(1-2): 171-80, 1998 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-9718692

RESUMEN

A commonly used additive to tobacco products is cocoa. A sensitive an selective method was developed to measure caffeine, a marker for cocoa, in tobacco by using gas chromatography-mass spectrometry (GC-MS). Tobacco components usually produce high background signals in GC-MS analysis. Therefore, a series of extraction steps were designed to effectively purify the tobacco extracts. The analytical recovery of caffeine was 100 when [trimethyl-13C3] caffeine was used as an isotope-dilution reference. A linear calibration curve was generated with caffeine concentration ranging from 0.01 to 20 micrograms/ml. The detection limit of caffeine was 0.02 microgram/ml in the final solution. This method was applied to several commercial tobacco products, of which the corresponding caffeine levels varied from below the detection limit to 125 micrograms/g.


Asunto(s)
Cafeína/aislamiento & purificación , Nicotiana/química , Plantas Tóxicas , Calibración , Cromatografía de Gases y Espectrometría de Masas , Ácido Clorhídrico , Reproducibilidad de los Resultados
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