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1.
Nature ; 614(7947): 287-293, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36725928

RESUMO

The ability of the ancient Egyptians to preserve the human body through embalming has not only fascinated people since antiquity, but also has always raised the question of how this outstanding chemical and ritual process was practically achieved. Here we integrate archaeological, philological and organic residue analyses, shedding new light on the practice and economy of embalming in ancient Egypt. We analysed the organic contents of 31 ceramic vessels recovered from a 26th Dynasty embalming workshop at Saqqara1,2. These vessels were labelled according to their content and/or use, enabling us to correlate organic substances with their Egyptian names and specific embalming practices. We identified specific mixtures of fragrant or antiseptic oils, tars and resins that were used to embalm the head and treat the wrappings using gas chromatography-mass spectrometry analyses. Our study of the Saqqara workshop extends interpretations from a micro-level analysis highlighting the socio-economic status of a tomb owner3-7 to macro-level interpretations of the society. The identification of non-local organic substances enables the reconstruction of trade networks that provided ancient Egyptian embalmers with the substances required for mummification. This extensive demand for foreign products promoted trade both within the Mediterranean8-10 (for example, Pistacia and conifer by-products) and with tropical forest regions (for example, dammar and elemi). Additionally, we show that at Saqqara, antiu and sefet-well known from ancient texts and usually translated as 'myrrh' or 'incense'11-13 and 'a sacred oil'13,14-refer to a coniferous oils-or-tars-based mixture and an unguent with plant additives, respectively.


Assuntos
Embalsamamento , Múmias , Humanos , Antigo Egito , Embalsamamento/economia , Embalsamamento/história , Embalsamamento/métodos , Cromatografia Gasosa-Espectrometria de Massas , História Antiga , Múmias/história , Resinas Vegetais/análise , Resinas Vegetais/história , Cerâmica/química , Cerâmica/história , Alcatrões/análise , Alcatrões/história , Óleos de Plantas/análise , Óleos de Plantas/história , Região do Mediterrâneo , Clima Tropical , Florestas , Traqueófitas/química , Comércio/história
2.
Chem Res Toxicol ; 34(7): 1713-1717, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34228438

RESUMO

Two-tail t test statistical analyses of International Organization for Standardization nonintense and Canadian Intense mainstream smoke yields of total particulate matter, tar, nicotine, and carbon monoxide from cigarettes show that mean quantities are generally higher for a linear smoking machine at a 95% confidence level but a rotary smoking machine has better precision. A novel "super pad" analysis concept combines four smaller filter pads from a linear smoking machine, resulting in increased mean constituent yields and reduced variability. Although measurement variability is still greater than that of rotary machines, super padding may be useful to reduce the variance caused by linear smoking machines.


Assuntos
Fumaça/análise , Canadá , Monóxido de Carbono/análise , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Humanos , Nicotina/análise , Material Particulado/análise , Fumar , Alcatrões/análise
3.
Nicotine Tob Res ; 22(6): 990-996, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-30726984

RESUMO

INTRODUCTION: Despite regulations that forbid cigarette packages from displaying messages such as "mild," "low-tar," and "light," many smokers still have misperceptions about "light" or "low-tar" cigarettes. One reason may be that tar amount displays continue to be permitted. This study examines whether removing tar delivery information from packaging reduces consumer misperceptions about "low-tar" cigarettes. METHODS: An online experiment was conducted in South Korea among 531 smokers who were randomly assigned to one of two conditions: with and without tar information on cigarette packages. Participants evaluated which type of cigarette was mildest, least harmful, easiest for nonsmokers to start smoking, and easiest for smokers to quit. RESULTS: Ten out of 12 chi-square tests showed that people judged the lowest reported tar delivery cigarette to be the mildest (p < .01), least harmful (p < .05), easiest to start (p < .05), and easiest to quit (p < .05)-less so in the "no-tar" condition than the "tar" condition. A higher level of misbeliefs about supposed low-tar cigarettes were found in the "tar" condition compared to the "no-tar" condition for all three brands (t = 5.85, 4.07, 3.82, respectively, p < .001). Regression analyses showed that the "no-tar" condition negatively predicted the level of misbeliefs after controlling for demographic and smoking-related variables (B [SE] = -.72 (.12), -.50 (.12), -.48 (.13), respectively, p < .001). CONCLUSIONS: Banning reported tar deliveries from cigarette packages is likely to reduce smokers' misconceptions about "low-tar" cigarettes. When reported tar deliveries are absent, smokers have inconsistent judgments about differently packaged cigarettes. IMPLICATIONS: When cigarette packages depict lower reported tar number deliveries, participants erroneously perceive them to be less harmful than packages displaying higher tar numbers. These misperceptions of harm may prompt smokers who might otherwise attempt to quit smoking to instead consume cigarettes with lower tar deliveries due to the mistaken belief that they will reduce their risk.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Embalagem de Produtos/métodos , Fumantes/psicologia , Fumar/psicologia , Alcatrões/química , Produtos do Tabaco/estatística & dados numéricos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Fumar/epidemiologia , Alcatrões/análise , Adulto Jovem
4.
Prev Med ; 129: 105828, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31479656

RESUMO

The intensity of tobacco use is commonly measured by the number of cigarettes, which is inaccurate because it masks the heterogeneity and substances contained in tobacco. Unlike existing studies, this study adopted the tar and nicotine content of purchased cigarettes as proxies for smoking intensity and elicited socioeconomic disparities from the participants regarding tobacco use. Using a nationally representative consumer panel survey of Japan from 2010 to 2014, we found that socioeconomic disparities in smoking are more pronounced when tar and nicotine content in cigarettes is considered. University graduates purchased 26% fewer cigarettes, and 40% less tar or nicotine than their secondary school-educated counterparts. Low education groups purchased more tar-rich cigarettes, which cost less than low-tar cigarettes. The public health recommendations for reducing socioeconomic health inequalities might be understated because they are drawn from evidence based on the number of cigarettes smoked.


Assuntos
Fumar Cigarros/economia , Comportamento do Consumidor , Escolaridade , Nicotina/análise , Alcatrões/análise , Adulto , Fumar Cigarros/efeitos adversos , Comportamento do Consumidor/economia , Comportamento do Consumidor/estatística & dados numéricos , Feminino , Humanos , Japão , Masculino , Fatores Socioeconômicos , Inquéritos e Questionários , Nicotiana
5.
Eur J Cancer Prev ; 28(1): 40-44, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-28683008

RESUMO

Cigarette smoking is a major risk factor for bladder cancer (BC); however, the impact of cigarette content remains unclear. This study aims to investigate tar, nicotine and carbon monoxide (TNCO) yields of different filtered cigarettes in relation to BC risk. From the Bladder Cancer Prognosis Programme 575 non-muscle-invasive bladder cancer (NMIBC) cases, 139 muscle-invasive bladder cancer (MIBC) cases and 130 BC-free controls with retrospective data on smoking behaviour and cigarette brand were identified. Independently measured TNCO yields of cigarettes sold in the UK were obtained through the UK Department of Health and merged with the Bladder Cancer Prognosis Programme dataset to estimate the daily intake of TNCO. BC risk increased by TNCO intake category for NMIBC cases (P <0.050 in all multivariate models), but only for the daily intake of tar for MIBC cases (P=0.046) in multivariate models. No difference in risk was observed between smokers of low-tar/low-nicotine and high-tar/high-nicotine cigarettes compared with never smokers, either for NMIBC (P=0.544) or MIBC (P=0.449). High daily intake of TNCO additionally increases the risk of both NMIBC and MIBC compared with low daily intake. However, as there is no difference in BC risk between low-tar/low-nicotine and high-tar/high-nicotine cigarette smokers, it remains unclear whether smoking behaviour or TNCO yield of cigarettes explains this association.


Assuntos
Monóxido de Carbono/efeitos adversos , Nicotina/efeitos adversos , Alcatrões/efeitos adversos , Produtos do Tabaco/efeitos adversos , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/epidemiologia , Idoso , Monóxido de Carbono/análise , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Nicotina/análise , Inquéritos e Questionários , Alcatrões/análise , Reino Unido/epidemiologia , Neoplasias da Bexiga Urinária/diagnóstico
6.
Nicotine Tob Res ; 21(8): 1045-1050, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29889248

RESUMO

INTRODUCTION: The Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study demonstrated that ß-carotene supplementation increases lung cancer incidence in smokers. Further, cigarettes with higher tar and nicotine content are associated with a higher risk of lung cancer. However, no studies have examined whether the increased risk associated with ß-carotene supplementation in smokers varies by the tar or nicotine content of cigarettes. METHODS: The ATBC Study was a randomized, double-blind intervention trial conducted in southwest Finland. A total of 29 133 male smokers, aged 50-69 years, were enrolled and randomly assigned to one of four groups (α-tocopherol, ß-carotene, both, or placebo). Cox proportional hazards models were used to estimate the hazard ratio (HR) and 95% confidence intervals (CI) of lung cancer risk by ß-carotene trial assignment stratified by a priori categories of cigarette tar and nicotine content. RESULTS: The ß-carotene supplementation group had significantly higher risk of developing lung cancer in all categories of tar content (yes vs. no ß-carotene supplementation-ultralight cigarettes [≤7 mg tar]: HR = 1.31, 95% CI = 0.91 to 1.89; nonfiltered cigarettes [≥21 mg tar]: HR = 1.22, 95% CI = 0.91 to 1.64; p for interaction = .91). Similarly, there was no interaction with nicotine content (yes vs. no ß-carotene supplementation-ventilated cigarettes [≤0.8 µg nicotine]: HR = 1.23, 95% CI = 0.98 to 1.54; nonfiltered cigarettes [≥1.3 µg nicotine]: HR = 1.22, 95% CI = 0.91 to 1.64; p for interaction = .83). CONCLUSION: These findings support the conclusion that supplementation with ß-carotene increases the risk of lung cancer in smokers regardless of the tar or nicotine content of cigarettes smoked. Our data suggest that all smokers should continue to avoid ß-carotene supplementation. IMPLICATIONS: Previous studies demonstrated that ß-carotene supplementation increases risk of lung cancer in smokers. This study moves the field forward by examining the potential for modification of risk of lung cancer with different levels of tar and nicotine in cigarettes smoked, as interaction with carcinogens in these components of cigarette smoke is hypothesized to be the mechanism by which ß-carotene increases risk. Our study provides evidence that the increased risk of lung cancer in smokers who take ß-carotene supplements is not dependent upon the tar or nicotine level of cigarettes smoked and suggests that all smokers should continue to avoid ß-carotene supplementation.


Assuntos
Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/prevenção & controle , Nicotina/análise , Fumar/efeitos adversos , Alcatrões/análise , beta Caroteno/efeitos adversos , Idoso , Antioxidantes/administração & dosagem , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Finlândia/epidemiologia , Seguimentos , Humanos , Incidência , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Provitaminas/efeitos adversos , Fumar/tratamento farmacológico , alfa-Tocoferol/administração & dosagem , beta Caroteno/administração & dosagem
7.
Sci Total Environ ; 650(Pt 2): 2150-2163, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30290356

RESUMO

A six-month laboratory scale study was carried out to investigate the effect of biochar and compost amendments on complex chemical mixtures of tar, heavy metals and metalloids in two genuine contaminated soils. An integrated approach, where organic and inorganic contaminants bioavailability and distribution changes, along with a range of microbiological indicators and ecotoxicological bioassays, was used to provide multiple lines of evidence to support the risk characterisation and assess the remediation end-point. Both compost and biochar amendment (p = 0.005) as well as incubation time (p = 0.001) significantly affected the total and bioavailable concentrations of the total petroleum hydrocarbons (TPH) in the two soils. Specifically, TPH concentration decreased by 46% and 30% in Soil 1 and Soil 2 amended with compost. These decreases were accompanied by a reduction of 78% (Soil 1) and 6% (Soil 2) of the bioavailable hydrocarbons and the most significant decrease was observed for the medium to long chain aliphatic compounds (EC16-35) and medium molecular weight aromatic compounds (EC16-21). Compost amendment enhanced the degradation of both the aliphatic and aromatic fractions in the two soils, while biochar contributed to lock the hydrocarbons in the contaminated soils. Neither compost nor biochar affected the distribution and behaviour of the heavy metals (HM) and metalloids in the different soil phases, suggesting that the co-presence of heavy metals and metalloids posed a low risk. Strong negative correlations were observed between the bioavailable hydrocarbon fractions and the ecotoxicological assays suggesting that when bioavailable concentrations decreased, the toxicity also decreased. This study showed that adopting a combined diagnostic approach can significantly help to identify optimal remediation strategies and contribute to change the over-conservative nature of the current risk assessments thus reducing the costs associated with remediation endpoint.


Assuntos
Carvão Vegetal/administração & dosagem , Compostagem , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/análise , Alcatrões/análise , Disponibilidade Biológica , Tomada de Decisões , Inglaterra , Biomarcadores Ambientais , Hidrocarbonetos Aromáticos/análise , Metaloides/análise , Metais Pesados/análise , Medição de Risco
8.
Mar Pollut Bull ; 137: 352-359, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30503444

RESUMO

Tar balls are prevalent in oceans and the coastal environment; however, their origins are not well constrained on a global scale. To address this, we used gas chromatography to analyze the molecular composition of a unique set of 100 pelagic tar balls collected in the Western North Atlantic and Caribbean Sea between 1988 and 2016. Hierarchal cluster analysis (HCA) was employed to classify the samples into groups based on the relative proportions of resolved and unresolved hydrocarbon distributions. Additional analysis of polycyclic aromatic hydrocarbons revealed that 28% of samples originated from heavy fuel oils and therefore had anthropogenic origins consistent with the classifications based on HCA. Other samples examined could originate from anthropogenic or natural origins, such as natural seeps. This study provides a preliminary record of 100 classified pelagic tar ball samples and demonstrates an approach to determine their origin to the environment.


Assuntos
Alcatrões/análise , Poluentes Químicos da Água/análise , Oceano Atlântico , Região do Caribe , Cromatografia Gasosa , Monitoramento Ambiental , Óleos Combustíveis/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Fatores de Tempo
9.
Chem Res Toxicol ; 31(6): 462-471, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29727173

RESUMO

The WHO study group on tobacco product regulation (TobReg) advised regulating and lowering toxicant levels in cigarette smoke. Aldehydes are one of the chemical classes on the TobReg smoke toxicants priority list. To provide insight in factors determining aldehyde yields, the levels of 12 aldehydes in mainstream cigarette smoke of 11 Dutch brands were quantified. Variations in smoking behavior and cigarette design affecting human exposure to aldehydes were studied by using four different machine testing protocols. Machine smoking was based on the International Standardization Organization (ISO) and Health Canada Intense (HCI) regime, both with and without taping the filter vents. The 11 cigarette brands differed in (i) design and blend characteristics; (ii) tar, nicotine, and carbon monoxide (TNCO) levels; (iii) popularity; and (iv) manufacturer. Cigarette smoke was trapped on a Cambridge filter pad and carboxen cartridge. After being dissolved in methanol/CS2 and derivatization with DNPH, the aldehyde yields were determined using HPLC-DAD. Using an intense smoking regime (increased puff volume, shorter puff interval) significantly increased aldehyde yields, following the pattern: ISO < ISO-taped < HCI-untaped < HCI. For all of the regimes, acetaldehyde and acrolein yields were strongly correlated ( r = 0.804). The difference in TNCO and aldehyde levels between regular and highly ventilated low-TNCO cigarettes (as measured using ISO) diminished when smoking intensely; this effect is stronger when combined with taping filter vents. The highly ventilated low-TNCO brands showed six times more aldehyde production per mg nicotine for the intense smoking regimes. In conclusion, acetaldehyde and acrolein can be used as representatives for the class of volatile aldehydes for the different brands and smoking regimes. The aldehyde-to-nicotine ratio increased when highly ventilated cigarettes were smoked intensely, similar to real smokers. Thus, a smoker of highly ventilated low-TNCO cigarettes has an increased potential for higher aldehyde exposures compared to a smoker of regular cigarettes.


Assuntos
Aldeídos/análise , Nicotiana , Fumaça/análise , Monóxido de Carbono/análise , Nicotina/análise , Fumar , Alcatrões/análise , Produtos do Tabaco , Ventilação
10.
J Anal Toxicol ; 42(7): 496-502, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29750269

RESUMO

In the Middle East, there is no precise data and literature on tobacco-based products, such as dokha and shisha. The proposed study aims to quantify the levels of nicotine and tar in different kinds of dokha and shisha products that are sold in the local marketplace. The amount of nicotine in dokha and shisha products can be quantitatively determined using a combination of the "kissling" and "silicotungstic acid" method proposed by Robert M. Chapin. The tar residue from the smoke sample was collected on a glass wool placed before the stopcock (tap) of a separatory funnel as the smoke passes through the inlet of an electronically controlled vacuum pump. The nicotine levels in dokha and shisha samples ranged from 23.83 to 52.80 mg/g and 0.80 to 20.52 mg/g, respectively. The nicotine level varies between different tobacco products. It varies from 0.5 to 19.5 mg/g in cigarettes, from 10.3 to 23.1 mg/g in snuff tobacco, from 11 to 18 mg/g in electronic cigarettes and from 2.9 to 16.6 mg/g in chewing tobacco. The tar levels in the dokha and shisha samples ranged from 21.6 to 45.02 mg/g and 1.68 to 11.87 mg/g, respectively. Smokers are at a high risk of getting lung cancer, chronic obstructive pulmonary disease, emphysema and coronary artery disease owing to the high levels of nicotine and tar present in dokha and shisha tobacco products. These findings contradict the widespread belief among teenagers that dokha and shisha tobacco products are safer alternatives to cigarettes.


Assuntos
Nicotina/análise , Cachimbos de Água , Alcatrões/análise , Tabaco para Cachimbos de Água/análise , Qualidade de Produtos para o Consumidor , Humanos , Nicotina/efeitos adversos , Medição de Risco , Alcatrões/efeitos adversos , Tabaco para Cachimbos de Água/efeitos adversos
11.
Inhal Toxicol ; 30(1): 5-18, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29488428

RESUMO

BACKGROUND: Opinions differ on the relationship between tar level and risk of smoking-related disease. However, except for lung cancer, few reviews have evaluated the epidemiological evidence. Here the relationship of tar level to risk of the four main smoking-related diseases is considered. METHODS: Papers comparing risk of lung cancer, COPD, heart disease or stroke in smokers of lower and higher tar yield cigarettes were identified from reviews and searches, relative risk estimates being extracted comparing the lowest and highest tar groups. Meta-analyses investigated heterogeneity by various study characteristics. RESULTS: Twenty-six studies were identified, nine of prospective design and 17 case-control. Two studies grouped cigarettes by nicotine rather than tar. Seventeen studies gave results for lung cancer, 16 for heart disease, five for stroke and four for COPD. Preferring relative risks adjusted for daily amount smoked, where adjusted and unadjusted estimates were available, combined estimates for lowest versus highest tar (or nicotine) groups were 0.78 (95% confidence interval 0.70-0.88) for lung cancer, 0.86 (0.81-0.91) for heart disease, 0.77 (0.62-0.95) for stroke and 0.81 (0.65-1.02) for COPD. Lower risks were generally evident in subgroups by publication period, gender, study design, location and extent of confounder adjustment. Estimates were similar preferring data unadjusted for amount smoked or excluding nicotine-based estimates. CONCLUSIONS: Despite evidence that smokers substantially compensate for reduced cigarette yields, the results clearly show lower risks in lower tar smokers. Limitations of the evidence are discussed, but seem unlikely to affect this conclusion.


Assuntos
Cardiopatias/epidemiologia , Neoplasias Pulmonares/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fumar/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Alcatrões/análise , Produtos do Tabaco/análise , Humanos , Fatores de Risco , Fumar/efeitos adversos , Produtos do Tabaco/efeitos adversos
12.
Shokuhin Eiseigaku Zasshi ; 58(3): 160-165, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28690307

RESUMO

Extraction and clean-up methods were examined for the analysis of acidic tar dyes in various high-protein foods. 1% Aqueous ammonia followed by ethanol, 1% aqueous ammonia-ethanol (1 : 1) mixture, and 1% aqueous ammonia-tetrahydrofuran (1 : 1) mixture were used in sequence for boiled fish paste (kamaboko), pounded fish cake (hanpen), and sausage. The sausage extract was centrifuged at low temperature to solidify and remove the contained fat. Salted cod roe with red pepper was extracted twice with 1% aqueous ammonia-ethanol (1 : 1) mixture, followed by extraction with 1% aqueous ammonia-tetrahydrofuran (1 : 1) mixture. A divinylbenzene-N-vinylpyrrolidone copolymer column was used for the clean-up of xanthen dyes. In the case of clogging-prone samples, the same type of large-particle-size column was used. A polyamide column was used for clean-up of the other dyes. When each dye was added at 5 µg/g in the foods, recoveries from kamaboko, hanpen, and sausage ranged from 76 to 102%, and the average recovery from the two types of salted cold roe with red pepper ranged from 45 to 98%.


Assuntos
Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Corantes de Alimentos/análise , Corantes de Alimentos/isolamento & purificação , Alcatrões/análise , Alcatrões/isolamento & purificação , Xantenos/análise , Xantenos/isolamento & purificação , Concentração de Íons de Hidrogênio , Polivinil , Extração em Fase Sólida/métodos
13.
Shokuhin Eiseigaku Zasshi ; 57(6): 207-212, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-28025455

RESUMO

The effect of pH of the clean-up process in the analysis of 11 permitted tar dyes in high protein food was investigated by using a handmade polyamide column (PA column) and Oasis HLB. Boiled fish paste spiked with the 11 dyes was extracted with appropriate solvents and the pH of the extract was adjusted to 3.0-7.0 in increments of 0.5, followed by clean-up with the PA column. At pH 3.0-5.5, precipitate formed in the extract clogged the column, and the recoveries of R3, R104 and R105 were 26-68%. At pH 6.0-7.0, clogging was not observed and the recoveries of the 3 dyes were somewhat higher, at 38-79%. The recoveries of other dyes were more than 80% at pH 3.0-7.0. With Oasis HLB, column loading was conducted at pH 11.0, and the recoveries of the 3 dyes improved to 70-83%. In conclusion, all 11 dyes could be cleaned-up with the PA column and Oasis HLB and the recoveries exceeded 70%.


Assuntos
Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Corantes de Alimentos/análise , Corantes de Alimentos/isolamento & purificação , Produtos da Carne/análise , Alcatrões/análise , Alcatrões/isolamento & purificação , Concentração de Íons de Hidrogênio , Nylons , Extração em Fase Sólida/métodos , Soluções
14.
Regul Toxicol Pharmacol ; 82: 111-126, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27634061

RESUMO

Cigarettes with reduced circumference are increasingly popular in some countries, hence it is important to understand the effects of circumference reduction on their burning behaviour, smoke chemistry and bioactivity. Reducing circumference reduces tobacco mass burn rate, puff count and static burn time, and increases draw resistance and rod length burned during puff and smoulder periods. Smoulder temperature increases with decreasing circumference, but with no discernible effect on cigarette ignition propensity during a standard test. At constant packing density, mainstream (MS) and sidestream (SS) tar and nicotine yields decrease approximately linearly with decreasing circumference, as do the majority of smoke toxicants. However, volatile aldehydes, particularly formaldehyde, show a distinctly non-linear relationship with circumference and increases in the ratios of aldehydes to tar and nicotine have been observed as the circumference decreases. Mutagenic, cytotoxic and tumorigenic specific activities of smoke condensates (i.e. per unit weight of condensate) decrease as circumference decreases. Recent studies suggest that there is no statistical difference in mouth-level exposure to tar and nicotine among smokers of cigarettes with different circumferences. Commercially available slim cigarettes usually have changes in other cigarette design features compared with cigarettes with standard circumference, so it is difficult to isolate the effect of circumference on the properties of commercial products. However, available data shows that changes in cigarette circumference offer no discernible change to the harm associated with smoking.


Assuntos
Fumaça/efeitos adversos , Fumaça/análise , Fumar/efeitos adversos , Produtos do Tabaco/efeitos adversos , Produtos do Tabaco/análise , Poluição por Fumaça de Tabaco/efeitos adversos , Poluição por Fumaça de Tabaco/análise , Animais , Comportamento do Consumidor , Qualidade de Produtos para o Consumidor , Humanos , Exposição por Inalação/efeitos adversos , Modelos Animais , Testes de Mutagenicidade , Nicotina/efeitos adversos , Nicotina/análise , Medição de Risco , Alcatrões/efeitos adversos , Alcatrões/análise , Temperatura , Fatores de Tempo
15.
Biol Pharm Bull ; 39(6): 898-902, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27251490

RESUMO

The gas phase of cigarette smoke is important from the viewpoint of human health, because it can pass through alveolar epithelium and enter the circulation. There is no standard method for the preparation of a gas phase extract of cigarette smoke (CSE), although CSE is widely used for research instead of whole cigarette smoke. We have established a standard method for the preparation of CSE. One cigarette per trial is continuously combusted under a reduced pressure generated by an aspiration pump with a velocity of 1.050 L/min: the main stream of the smoke is passed through a Cambridge filter to remove tar, and subsequently, bubbled through a glass ball filter (pore size, 20-30 µm) into 15 mL of phosphate-buffered saline (PBS). To express the concentration of CSE, a virtual tar concentration is introduced, which is calculated assuming that tar trapped on the Cambridge filter is dissolved in the PBS. CSEs prepared from smaller numbers of cigarettes (original virtual tar concentration≤15 mg/mL) show similar concentration-response curves for cytotoxicity versus virtual tar concentrations. CSEs prepared from various brands of cigarettes and by different smoking regimes (continuous and puff smoking) show similar cytotoxic potency if the virtual tar concentrations are the same. In conclusion, using the standardized method for CSE preparation in combination with the virtual tar concentration, it becomes possible to simply and rapidly prepare standard CSEs with defined concentrations from any brand of cigarettes, which are toxicologically equivalent to CSE prepared by puff smoking.


Assuntos
Nicotiana , Fumaça/análise , Gases/análise , Humanos , Fumar , Alcatrões/análise , Produtos do Tabaco
16.
Chem Res Toxicol ; 29(6): 1051-63, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27222918

RESUMO

The aim of this study is to explore how differences in cigarette physical design parameters influence tar, nicotine, and carbon monoxide (TNCO) yields in mainstream smoke (MSS) using the International Organization of Standardization (ISO) smoking regimen. Standardized smoking methods were used to evaluate 50 U.S. domestic brand cigarettes and a reference cigarette representing a range of TNCO yields in MSS collected from linear smoking machines using a nonintense smoking regimen. Multivariate statistical methods were used to form clusters of cigarettes based on their ISO TNCO yields and then to explore the relationship between the ISO generated TNCO yields and the nine cigarette physical design parameters between and within each cluster simultaneously. The ISO generated TNCO yields in MSS are 1.1-17.0 mg tar/cigarette, 0.1-2.2 mg nicotine/cigarette, and 1.6-17.3 mg CO/cigarette. Cluster analysis divided the 51 cigarettes into five discrete clusters based on their ISO TNCO yields. No one physical parameter dominated across all clusters. Predicting ISO machine generated TNCO yields based on these nine physical design parameters is complex due to the correlation among and between the nine physical design parameters and TNCO yields. From these analyses, it is estimated that approximately 20% of the variability in the ISO generated TNCO yields comes from other parameters (e.g., filter material, filter type, inclusion of expanded or reconstituted tobacco, and tobacco blend composition, along with differences in tobacco leaf origin and stalk positions and added ingredients). A future article will examine the influence of these physical design parameters on TNCO yields under a Canadian Intense (CI) smoking regimen. Together, these papers will provide a more robust picture of the design features that contribute to TNCO exposure across the range of real world smoking patterns.


Assuntos
Modelos Estatísticos , Fumaça/análise , Produtos do Tabaco/análise , Monóxido de Carbono/análise , Monóxido de Carbono/normas , Cooperação Internacional , Análise Multivariada , Nicotina/análise , Nicotina/normas , Padrões de Referência , Alcatrões/análise , Alcatrões/normas , Produtos do Tabaco/normas
17.
Public Health Rep ; 131(1): 76-85, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26843673

RESUMO

OBJECTIVE: Waterpipe tobacco smoking (WTS) is an emerging trend worldwide. To inform public health policy and educational programming, we systematically reviewed the biomedical literature to compute the inhaled smoke volume, nicotine, tar, and carbon monoxide (CO) associated with a single WTS session and a single cigarette. METHODS: We searched seven biomedical bibliographic databases for controlled laboratory or natural environment studies designed to mimic human tobacco consumption. Included studies quantified the mainstream smoke of a single cigarette and/or single WTS session for smoke volume, nicotine, tar, and/or CO. We conducted meta-analyses to calculate summary estimates for the inhalation of each unique substance for each mode of tobacco consumption. We assessed between-study heterogeneity using chi-squared and I-squared statistics. RESULTS: Sufficient data from 17 studies were available to derive pooled estimates for inhalation of each exposure via each smoking method. Two researchers working independently abstracted measurement of smoke volume in liters, and nicotine, tar, and CO in milligrams. All numbers included in meta-analyses matched precisely between the two researchers (100% agreement, Cohen's k=1.00). Whereas one WTS session was associated with 74.1 liters of smoke inhalation (95% confidence interval [CI] 38.2, 110.0), one cigarette was associated with 0.6 liters of smoke (95% CI 0.5, 0.7). One WTS session was also associated with higher levels of nicotine, tar, and CO. CONCLUSIONS: One WTS session consistently exposed users to larger smoke volumes and higher levels of tobacco toxicants compared with one cigarette. These computed estimates may be valuable to emphasize in prevention programming.


Assuntos
Fumar/efeitos adversos , Monóxido de Carbono/análise , Humanos , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Nicotina/análise , Alcatrões/análise
18.
Tob Control ; 25(5): 575-83, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26292701

RESUMO

OBJECTIVES: To assess the 'Massachusetts Benchmark Study' (MBS) that the tobacco companies presented to the Massachusetts Department of Public Health (MDPH) in 1999 in response to ingredient disclosure regulations in the state. This case study can inform future ingredient disclosure regulations, including implementation of Articles 9 and 10 of the WHO Framework Convention on Tobacco Control (FCTC). METHODS: We analysed documents available at http://legacy.library.ucsf.edu to identify internal communications regarding the design and execution of the MBS and internal studies on the relationship between tar, nicotine and carbon monoxide and smoke constituents and reviewed publications that further evaluated data published as part of the MBS. RESULTS: The companies conducted extensive studies of cigarette design factors and ingredients that significantly impacted the levels of constituents. While this study asserted that by-brand emissions could be estimated reliably from published tar, nicotine, and carbon monoxide levels, the tobacco companies were well aware that factors beyond tar, nicotine and carbon monoxide influenced levels of constituents included in the study. This severely limited the potential usefulness of the MBS predictor equations. CONCLUSIONS: Despite promises to provide data that would allow regulators to predict constituent data for all brands on the market, the final MBS results offered no useful predictive information to inform regulators, the scientific community or consumers. When implementing FCTC Articles 9 and 10, regulatory agencies should demand detailed by-brand information on tobacco product constituents and toxin deliveries to users.


Assuntos
Revelação/legislação & jurisprudência , Fumaça/análise , Indústria do Tabaco/legislação & jurisprudência , Produtos do Tabaco/legislação & jurisprudência , Benchmarking , Monóxido de Carbono/análise , Humanos , Massachusetts , Nicotina/análise , Alcatrões/análise , Produtos do Tabaco/análise
19.
Water Environ Res ; 88(9): 847-851, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26488721

RESUMO

Submerged tar-contaminated sediment are generally very loose, which makes remediation challenging. We tested if a modified version of freeze-dredging could be used to remove and dewater such sediment in a canal down-stream a coking plant. PVC hoses carrying a heat medium were placed horizontally in the submerged sediment. Five days of freezing allowed straightforward removal of most of the sediment. Flat freeze cells were placed side by side in the canal to remove the rest. The freeze-thaw process increased the dry substance content from approximately 50 to 80%. Outdoors storage under rainy conditions did not re-wet the dried sediment. The material was successfully used as feed-stock in the coking plant, with the double cost-benefit of avoided transportation to deposit and reduced use of coal. The study demonstrates that freeze-dredging can facilitate removal, storage and beneficial re-use of submerged tar-contaminated sediment.


Assuntos
Sedimentos Geológicos/química , Reciclagem/métodos , Alcatrões/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Coque , Sedimentos Geológicos/análise , Resíduos Industriais/análise , Suécia , Alcatrões/análise , Poluentes Químicos da Água/análise
20.
N Engl J Med ; 373(14): 1340-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26422724

RESUMO

BACKGROUND: The Food and Drug Administration can set standards that reduce the nicotine content of cigarettes. METHODS: We conducted a double-blind, parallel, randomized clinical trial between June 2013 and July 2014 at 10 sites. Eligibility criteria included an age of 18 years or older, smoking of five or more cigarettes per day, and no current interest in quitting smoking. Participants were randomly assigned to smoke for 6 weeks either their usual brand of cigarettes or one of six types of investigational cigarettes, provided free. The investigational cigarettes had nicotine content ranging from 15.8 mg per gram of tobacco (typical of commercial brands) to 0.4 mg per gram. The primary outcome was the number of cigarettes smoked per day during week 6. RESULTS: A total of 840 participants underwent randomization, and 780 completed the 6-week study. During week 6, the average number of cigarettes smoked per day was lower for participants randomly assigned to cigarettes containing 2.4, 1.3, or 0.4 mg of nicotine per gram of tobacco (16.5, 16.3, and 14.9 cigarettes, respectively) than for participants randomly assigned to their usual brand or to cigarettes containing 15.8 mg per gram (22.2 and 21.3 cigarettes, respectively; P<0.001). Participants assigned to cigarettes with 5.2 mg per gram smoked an average of 20.8 cigarettes per day, which did not differ significantly from the average number among those who smoked control cigarettes. Cigarettes with lower nicotine content, as compared with control cigarettes, reduced exposure to and dependence on nicotine, as well as craving during abstinence from smoking, without significantly increasing the expired carbon monoxide level or total puff volume, suggesting minimal compensation. Adverse events were generally mild and similar among groups. CONCLUSIONS: In this 6-week study, reduced-nicotine cigarettes versus standard-nicotine cigarettes reduced nicotine exposure and dependence and the number of cigarettes smoked. (Funded by the National Institute on Drug Abuse and the Food and Drug Administration Center for Tobacco Products; ClinicalTrials.gov number, NCT01681875.).


Assuntos
Exposição por Inalação/análise , Nicotiana/química , Nicotina/normas , Produtos do Tabaco/normas , Tabagismo , Biomarcadores/urina , Creatinina/urina , Método Duplo-Cego , Humanos , Modelos Lineares , Nicotina/administração & dosagem , Nicotina/efeitos adversos , Síndrome de Abstinência a Substâncias , Alcatrões/análise , Alcatrões/normas , Produtos do Tabaco/análise , Tabagismo/prevenção & controle , Estados Unidos , United States Food and Drug Administration
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