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1.
Chem Res Toxicol ; 37(2): 220-226, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38235526

RESUMO

We measured levels of nitrosonornicotine (NNN) and 4-[methyl(nitroso)amino]-1-(3-pyridinyl)-1-butanone (NNK), the two most carcinogenic tobacco-specific nitrosamines, in the filler, binder, and wrapper of 50 cigars: 19 large cigars, 23 cigarillos, and 8 little cigars. The average NNN and NNK levels were 10.6 and 3.70 µg/g, respectively. These levels are 5- and 7-fold higher, respectively, than those of commercial cigarettes. The differences in NNN and NNK levels between cigars and cigarettes reflect differences in tobacco blends and tobacco treatments, such as fermentation. The average tobacco NNN and NNK levels of large cigars were 3- and 5-fold higher than those of cigarillos and little cigars, respectively. Large cigars also exhibited a significantly broader range of NNN and NNK than cigarillos and little cigars. The NNN and NNK levels in cigarillos are comparable to those of little cigars. These results are consistent with earlier studies finding that cigarillos and little cigars have similar tobacco blends with lower NNN and NNK content than large cigar tobacco blends.


Assuntos
Nitrosaminas , Produtos do Tabaco , Carcinógenos/análise
3.
PLoS One ; 17(5): e0267104, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35507593

RESUMO

BACKGROUND: Smokeless tobacco (ST) products are widely used throughout the world and contribute to morbidity and mortality in users through an increased risk of cancers and oral diseases. Bacterial populations in ST contribute to taste, but their presence can also create carcinogenic, Tobacco-Specific N-nitrosamines (TSNAs). Previous studies of microbial communities in tobacco products lacked chemistry data (e.g. nicotine, TSNAs) to characterize the products and identify associations between carcinogen levels and taxonomic groups. This study uses statistical analysis to identify potential associations between microbial and chemical constituents in moist snuff products. METHODS: We quantitatively analyzed 38 smokeless tobacco products for TSNAs using liquid chromatography with tandem mass spectrometry (LC-MS/MS), and nicotine using gas chromatography with mass spectrometry (GC-MS). Moisture content determinations (by weight loss on drying), and pH measurements were also performed. We used 16S rRNA gene sequencing to characterize the microbial composition, and additionally measured total 16S bacterial counts using a quantitative PCR assay. RESULTS: Our findings link chemical constituents to their associated bacterial populations. We found core taxonomic groups often varied between manufacturers. When manufacturer and flavor were controlled for as confounding variables, the genus Lactobacillus was found to be positively associated with TSNAs. while the genera Enteractinococcus and Brevibacterium were negatively associated. Three genera (Corynebacterium, Brachybacterium, and Xanthomonas) were found to be negatively associated with nicotine concentrations. Associations were also investigated separately for products from each manufacturer. Products from one manufacturer had a positive association between TSNAs and bacteria in the genus Marinilactibacillus. Additionally, we found that TSNA levels in many products were lower compared with previously published chemical surveys. Finally, we observed consistent results when either relative or absolute abundance data were analyzed, while results from analyses of log-ratio-transformed abundances were divergent.


Assuntos
Microbiota , Nitrosaminas , Tabaco sem Fumaça , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Microbiota/genética , Nicotina/análise , Nitrosaminas/análise , RNA Ribossômico 16S/genética , Espectrometria de Massas em Tandem , Nicotiana/química , Tabaco sem Fumaça/efeitos adversos , Tabaco sem Fumaça/análise
4.
Chem Res Toxicol ; 34(4): 1034-1045, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33667338

RESUMO

Cigars are among the broad variety of tobacco products that have not been as extensively studied and characterized as cigarettes. Small cigars wrapped in a tobacco-containing sheet, commonly referred to as little cigars, are a subcategory that are similar to conventional cigarettes with respect to dimensions, filters, and overall appearance. Tobacco-specific nitrosamines (TSNAs) are carcinogens in the tobacco used in both little cigars and cigarettes. This study uses a validated high-performance liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) method to measure the TSNAs 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN) in the tobacco filler and the nonintense International Organization for Standardization smoking regimen, ISO 3308, and the newer ISO 20778 Cigarette Intensive (CI) smoking regimen mainstream smoke of 60 commercial little cigars. Tobacco filler NNK and NNN quantities ranged from 26 to 2950 and 1440 to 12 100 ng/g tobacco, respectively. NNK and NNN by the ISO nonintense smoking regimen ranged from 89 to 879 and 200 to 1540 ng/cigar, respectively; by the CI regimen, NNK and NNN ranged from 138 to 1570 and 445 to 2780 ng/cigar, respectively. The average transfer (%) for NNK and NNN from tobacco filler to mainstream smoke was 24% and 36% by the ISO nonintense and CI smoking regimens, respectively. By the ISO nonintense and CI smoking regimens, mainstream smoke NNK and NNN yields showed a moderate to strong correlation (ISO nonintense, R2 = 0.60-0.68, p < 0.0001; CI, R2 = 0.78-0.81, p < 0.0001) with tobacco filler NNK and NNN quantities. In addition, the mainstream smoke NNK and NNN yields of little cigars were determined to be 3- to 5-fold higher compared to previously tested commercial cigarettes. The mainstream smoke NNK and NNN yields have wide variation among commercial little cigars and suggest that, despite design similarities to cigarettes, machine-smoke yields of carcinogenic TSNAs are higher in little cigars.


Assuntos
Nicotiana/química , Nitrosaminas/análise , Fumaça/análise , Produtos do Tabaco/análise
6.
Tob Regul Sci ; 2(2): 94-105, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26779559

RESUMO

OBJECTIVE: To provide researchers an extensive characterization of the SPECTRUM variable nicotine research cigarettes. METHODS: Data on cigarette physical properties, nicotine content, harmful and potentially harmful constituents in the tobacco filler was compiled. RESULTS: Data on physical properties, concentrations of menthol, nicotine and minor alkaloids, tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons, ammonia, and toxic metals in the filler tobacco for all available varieties of Spectrum research cigarettes are provided. The similarity in the chemistry and physical properties of SPECTRUM cigarettes to commercial cigarettes renders them acceptable for use in behavioral studies. Baseline information on harmful and potentially harmful constituents in research tobacco products, particularly constituent levels such as minor alkaloids that fall outside typical ranges reported for commercial, provide researchers with the opportunity to monitor smoking behavior and to identify biomarkers that will inform efforts to understand the role of nicotine in creating and sustaining addiction. CONCLUSIONS: Well characterized research cigarettes suitable for human consumption are an important tool in clinical studies for investigating the physiological impacts of cigarettes delivering various levels of nicotine, the impact of reduced nicotine cigarettes on nicotine addiction, and the relationship between nicotine dose and smoking behavior.

7.
Food Chem Toxicol ; 82: 50-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25934468

RESUMO

Rapé, a diverse group of smokeless tobacco products indigenous to South America, is generally used as a nasal snuff and contains substantial amount of plant material with or without tobacco. Previously uncharacterized, rapé contains addictive and harmful chemicals that may have public health implications for users. Here we report % moisture, pH, and the levels of total nicotine, un-ionized nicotine, flavor-related compounds, tobacco-specific N-nitrosamines (TSNAs) and polycyclic aromatic hydrocarbons (PAHs) for manufactured and hand-made rapé. Most rapé products were mildly acidic (pH 5.17-6.23) with total nicotine ranging from 6.32 to 47.6 milligram per gram of sample (mg/g). Calculated un-ionized nicotine ranged from 0.03 to 18.5 mg/g with the highest values associated with hand-made rapés (pH 9.75-10.2), which contain alkaline ashes. In tobacco-containing rapés, minor alkaloid levels and Fourier transform infrared spectra were used to confirm the presence of Nicotiana rustica, a high nicotine tobacco species. There was a wide concentration range of TSNAs and PAHs among the rapés analyzed. Several TSNAs and PAHs identified in the products are known or probable carcinogens according to the International Agency for Research on Cancer. Milligram quantities of some non-tobacco constituents, such as camphor, coumarin, and eugenol, warrant additional evaluation.


Assuntos
Nicotina/análise , Nitrosaminas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Tabaco sem Fumaça/análise , Alcaloides/análise , Brasil , Cinnamomum zeylanicum/química , Eugenol/análise , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Mentol/análise , Nicotina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Massas em Tandem , Nicotiana/química
8.
Anal Chim Acta ; 787: 267-73, 2013 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-23830449

RESUMO

Human exposure to N,N-diethyl-m-toluamide (DEET) occurs because of the widespread use of DEET as an active ingredient in insect repellents. However, information on the extent of such exposure is rather limited. Therefore, we developed a fast on-line solid phase extraction-high performance liquid chromatography-isotope dilution tandem mass spectrometry (HPLC-MS/MS) method to measure in urine the concentrations of DEET and two of its oxidative metabolites: N,N-diethyl-3-(hydroxymethyl)benzamide and 3-(diethylcarbamoyl)benzoic acid (DCBA). To the best of our knowledge, this is the first HPLC-MS/MS method for the simultaneous quantification of DEET and its select metabolites in human urine. After enzymatic hydrolysis of the conjugated species in 0.1 mL of urine, the target analytes were retained and pre-concentrated on a monolithic column, separated from each other and from other urinary biomolecules on a reversed-phase analytical column, and detected by atmospheric pressure chemical ionization in positive ion mode. The limits of detection ranged from 0.1 ng mL(-1) to 1.0 ng mL(-1), depending on the analyte. Accuracy ranged between 90.4 and 104.9%, and precision ranged between 5.5 and 13.1% RSD, depending on the analyte and the concentration. We tested the usefulness of this method by analyzing 75 urine samples collected anonymously in the Southeastern United States in June 2012 from adults with no known exposure to DEET. Thirty eight samples (51%) tested positive for at least one of the analytes. We detected DCBA most frequently and at the highest concentrations. Our results suggest that this method can be used for the analysis of a large number of samples for epidemiological studies to assess human exposure to DEET.


Assuntos
DEET/urina , Estresse Oxidativo/fisiologia , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , DEET/metabolismo , Feminino , Humanos , Masculino
9.
Artigo em Inglês | MEDLINE | ID: mdl-23648311

RESUMO

Organophosphate and pyrethroid insecticides and phenoxyacetic acid herbicides represent important classes of pesticides applied in commercial and residential settings. Interest in assessing the extent of human exposure to these pesticides exists because of their widespread use and their potential adverse health effects. An analytical method for measuring 12 biomarkers of several of these pesticides in urine has been developed. The target analytes were extracted from one milliliter of urine by a semi-automated solid phase extraction technique, separated from each other and from other urinary biomolecules by reversed-phase high performance liquid chromatography, and detected using tandem mass spectrometry with isotope dilution quantitation. This method can be used to measure all the target analytes in one injection with similar repeatability and detection limits of previous methods which required more than one injection. Each step of the procedure was optimized to produce a robust, reproducible, accurate, precise and efficient method. The required selectivity and sensitivity for trace-level analysis (e.g., limits of detection below 0.5ng/mL) was achieved using a narrow diameter analytical column, higher than unit mass resolution for certain analytes, and stable isotope labeled internal standards. The method was applied to the analysis of 55 samples collected from adult anonymous donors with no known exposure to the target pesticides. This efficient and cost-effective method is adequate to handle the large number of samples required for national biomonitoring surveys.


Assuntos
Herbicidas/urina , Espectrometria de Massas/métodos , Praguicidas/urina , Piretrinas/urina , Extração em Fase Sólida/métodos , Humanos , Organofosfatos/urina , Reprodutibilidade dos Testes
10.
J Pharm Biomed Anal ; 52(2): 260-4, 2010 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-20102787

RESUMO

Ethyl methanesulfonate (EMS) is a mesylate ester, which is known to be a potent mutagen, teratogen, and possibly carcinogen. Mesylate esters have been found in pharmaceuticals as contaminants formed during the manufacturing process and may potentially pose an exposure hazard to humans. We have developed and validated a method for detection of trace amounts (ng/ml levels) of EMS in human plasma and breast milk. The samples were extracted by matrix solid-phase dispersion with ethyl acetate using Hydromatrix and the ASE 200 Accelerated Solvent Extractor. The extracts were separated by high-performance liquid chromatography (HPLC) using a HILIC column. The detection was performed with a triple quadrupole mass spectrometer (TSQ Quantum Ultra, Thermo Electron Corporation) using atmospheric pressure chemical ionization in negative-ion mode and multiple reaction monitoring. The use of a surrogate internal standard in combination with HPLC-MS/MS provided a high degree of accuracy and precision. The extraction efficiency was greater than 70%. Repeated analyses of plasma and breast milk samples spiked with high (100 ng/ml), medium (50 ng/ml) and low (5 ng/ml) concentrations of the analytes gave relative standard deviations of less than 12%. The limits of detection were in the range of 0.5-0.9 ng/ml for both matrices.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Metanossulfonato de Etila/sangue , Leite Humano/química , Mutagênicos/análise , Espectrometria de Massas em Tandem/métodos , Pressão Atmosférica , Calibragem , Metanossulfonato de Etila/química , Feminino , Humanos , Limite de Detecção , Estrutura Molecular , Peso Molecular , Gravidez , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Bull World Health Organ ; 86(10): 749-56, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18949211

RESUMO

OBJECTIVE: In September 2006, a Panamanian physician reported an unusual number of patients with unexplained acute renal failure frequently accompanied by severe neurological dysfunction. Twelve (57%) of 21 patients had died of the illness. This paper describes the investigation into the cause of the illness and the source of the outbreak. METHODS: Case-control and laboratory investigations were implemented. Case patients (with acute renal failure of unknown etiology and serum creatinine > 2 mg/dl) were individually matched to hospitalized controls for age (+/- 5 years), sex and admission date (< 2 days before the case patient). Questionnaire and biological data were collected. The main outcome measure was the odds of ingesting prescription cough syrup in cases and controls. FINDINGS: Forty-two case patients and 140 control patients participated. The median age of cases was 68 years (range: 25-91 years); 64% were male. After controlling for pre-existing hypertension and renal disease and the use of angiotensin-converting enzyme inhibitors, a significant association was found between ingestion of prescription cough syrup and illness onset (adjusted odds ratio: 31.0, 95% confidence interval: 6.93-138). Laboratory analyses confirmed the presence of diethylene glycol (DEG) in biological samples from case patients, 8% DEG contamination in cough syrup samples and 22% contamination in the glycerin used to prepare the cough syrup. CONCLUSION: The source of the outbreak was DEG-contaminated cough syrup. This investigation led to the recall of approximately 60 000 bottles of contaminated cough syrup, widespread screening of potentially exposed consumers and treatment of over 100 affected patients.


Assuntos
Injúria Renal Aguda/epidemiologia , Surtos de Doenças , Etilenoglicóis/intoxicação , Injúria Renal Aguda/induzido quimicamente , Adolescente , Adulto , Idoso , Antitussígenos/análise , Estudos de Casos e Controles , Contaminação de Medicamentos , Etilenoglicóis/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Panamá/epidemiologia , Adulto Jovem
13.
Anal Bioanal Chem ; 391(5): 1931-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18454284

RESUMO

We have developed a method using on-line solid-phase extraction-high-performance liquid chromatography-tandem mass spectrometry (SPE-HPLC-MS/MS) and isotope dilution quantification to measure atrazine and seven atrazine metabolites in urine. The metabolites measured were hydroxyatrazine, diaminochloroatrazine, desisopropylatrazine, desethylatrazine, desethylatrazine mercapturate, atrazine mercaturate and atrazine itself. Our method has good precision (relative standard deviations ranging from 4 to 20% at 5, 10 and 50 ng/mL), extraction efficiencies of 67 to 102% at 5 and 25 ng/mL, relative recoveries of 87 to 112% at 5, 25, 50 and 100 ng/mL limits of detection (LOD) ranging from 0.03 to 2.80 ng/mL. The linear range of our method spans from the analyte LOD to 100 ng/mL (40 ng/mL for atrazine and atrazine mercapturate) with R (2) values of greater than 0.999 and errors about the slope of less than 3%. Our method is rapid, cost-effective and suitable for large-scale sample analyses and is easily adaptable to other biological matrices. More importantly, this method will allow us to better assess human exposure to atrazine-related chemicals.


Assuntos
Atrazina/urina , Cromatografia Líquida/métodos , Herbicidas/urina , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Atrazina/análogos & derivados , Humanos , Técnica de Diluição de Radioisótopos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
14.
J Expo Sci Environ Epidemiol ; 17(4): 321-30, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17440487

RESUMO

Because of increasing concern about widespread use of insecticides and fungicides, we have developed a highly sensitive analytical method to quantify urine-specific urinary biomarkers of the organophosphorus pesticides acephate, methamidophos, omethoate, dimethoate, and two metabolites from the fungicides alkylenebis-(dithiocarbamate) family: ethylenethiourea and propylenethiourea. The general sample preparation included lyophilization of the urine samples followed by extraction with dichloromethane. The analytical separation was performed by high-performance liquid chromatography (HPLC), and detection by a triple quadrupole mass spectrometer with and atmospheric pressure chemical ionization source in positive ion mode using multiple reaction monitoring and tandem mass spectrometry (MS/MS) analysis. Two different Thermo-Finnigan (San Jose, CA, USA) triple quadrupole mass spectrometers, a TSQ 7,000 and a TSQ Quantum Ultra, were used in these analyses; results are presented comparing the method specifications of these two instruments. Isotopically labeled internal standards were used for three of the analytes. The use of labeled internal standards in combination with HPLC-MS/MS provided a high degree of selectivity and precision. Repeated analysis of urine samples spiked with high, medium and low concentration of the analytes gave relative standard deviations of less than 18%. For all compounds the extraction efficiency ranged between 52% and 63%, relative recoveries were about 100%, and the limits of detection were in the range of 0.001-0.282 ng/ml.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Inseticidas/urina , Compostos Organotiofosforados/urina , Espectrometria de Massas em Tandem/métodos , Tioureia/análogos & derivados , Tioureia/urina , Pressão Atmosférica , Criança , Dimetoato/análogos & derivados , Dimetoato/química , Dimetoato/metabolismo , Dimetoato/urina , Etilenotioureia/química , Etilenotioureia/metabolismo , Feminino , Humanos , Inseticidas/química , Inseticidas/metabolismo , Compostos Organotiofosforados/química , Compostos Organotiofosforados/metabolismo , Fosforamidas , Gravidez , Tioureia/química , Tioureia/metabolismo
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