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1.
FASEB Bioadv ; 6(2): 53-71, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38344410

RESUMEN

Inhaling xenobiotics, such as tobacco smoke is a major risk factor for pulmonary diseases, e.g., COPD/emphysema, interstitial lung disease, and pre-invasive diseases. Shelterin complex or telosome provides telomeric end protection during replication. Telomere protection protein 1 (TPP1) is one of the main six subunits of the shelterin complex supporting the telomere stability and genomic integrity. Dysfunctional telomeres and shelterin complex are associated as a disease mechanism of tobacco smoke-induced pulmonary damage and disease processes. The airway epithelium is critical to maintaining respiratory homeostasis and is implicated in lung diseases. Club cells (also known as clara cells) play an essential role in the immune response, surfactant production, and metabolism. Disrupted shelterin complex may lead to dysregulated cellular function, DNA damage, and disease progression. However, it is unknown if the conditional removal of TPP1 from Club cells can induce lung disease pathogenesis caused by tobacco smoke exposure. In this study, conditional knockout of Club-cell specific TPP1 demonstrated the instability of other shelterin protein subunits, such as TRF1, dysregulation of cell cycle checkpoint proteins, p53 and downstream targets, and dysregulation of telomeric genes. This was associated with age-dependent senescence-associated genes, increased DNA damage, and upregulated RANTES/IL13/IL33 mediated lung inflammation and injury network by cigarette smoke (CS). These phenomena are also associated with alterations in cytochrome P450 and glutathione transferases, upregulated molecular pathways promoting lung lesions, bronchial neoplasms, and adenocarcinomas. These findings suggest a pivotal role of TPP1 in maintaining lung homeostasis and injurious responses in response to CS. Thus, these data TPP1 may have therapeutic value in alleviating telomere-related chronic lung diseases.

2.
Regul Toxicol Pharmacol ; 142: 105427, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37290570

RESUMEN

China is the world's largest consumer of cigarettes. However, the potential cancer risk posed by polycyclic aromatic hydrocarbons (PAHs) in mainstream cigarette smoke, especially species other than benzo[a]pyrene (BaP) remains unclear. In this study, we collected yield data on multiple PAH species from a variety of cigarettes in the China market and calculated their smoking-related incremental lifetime cancer risk (ILCR) values. The computed ILCRs of the total PAHs (ILCRΣPAHs) for ≥95% of the brands were one order of magnitude higher than the acceptable level. ILCRBaP accounted for only 5.0%-37.7% of ILCRΣPAHs among brands, indicating that using single analyte BaP to represent ΣPAHs would significantly underestimate ILCRΣPAHs. No clear trend of changes in ILCRΣPAHs was found for Chinese cigarettes over multiple years, suggesting that smoking cessation is still the best option to minimize the cancer risk of PAHs. The comparison study showed that rarely reported PAHs from Chinese cigarettes can contribute over half of ILCRΣPAHs for several American cigarettes, highlighting the imperativeness to improve the diversity of analytes for Chinese cigarettes. Adults would need to inhale the air-borne PAHs with a BaP equivalent concentration of at least 53.1 ng/m3 to reach the ILCR value comparable to that obtained from smoking.


Asunto(s)
Contaminantes Atmosféricos , Neoplasias , Hidrocarburos Policíclicos Aromáticos , Productos de Tabaco , Humanos , Adulto , Neoplasias/inducido químicamente , Neoplasias/epidemiología , Productos de Tabaco/efectos adversos , Nicotiana , China , Medición de Riesgo , Monitoreo del Ambiente , Contaminantes Atmosféricos/análisis
3.
Artículo en Inglés | MEDLINE | ID: mdl-36293731

RESUMEN

Secondhand smoke (SHS), composed of mainstream and sidestream smoke, is a known human carcinogen. It contains a variety of harmful substances at even higher concentrations than mainstream smoke itself, which is inhaled during firsthand smoking. Exposure to SHS, affecting more than a third of the worldwide population, increases the likelihood of lung cancer by roughly 30%, with specific contributions depending on the histological type of cancer. This study aimed to present the harmful potential of SHS through case reports and describe the burden of SHS via a literature review. From a collection of lung cancer case reports occurring in never smokers from the Olomouc district over the last 10 years, 2 cases with no risk factors for lung cancer except for significant exposure to SHS were identified. Both cases were of young women who lived in households where their parents smoked during childhood. They suffered from rarer histological types of lung cancer in which the association with SHS has not yet been analyzed. As the literature confirms, SHS has the most adverse effects in individuals exposed during childhood. It is necessary to both take measures to reduce the prevalence of SHS, especially among children in households and pay due attention to the smoking history of patients, including current and previous exposure to SHS, when obtaining anamnestic data. Furthermore, the effect of SHS on rarer histological types of lung cancer should be studied.


Asunto(s)
Neoplasias Pulmonares , Contaminación por Humo de Tabaco , Niño , Humanos , Femenino , Contaminación por Humo de Tabaco/efectos adversos , Contaminación por Humo de Tabaco/análisis , Salud Pública , Exposición a Riesgos Ambientales/efectos adversos , Neoplasias Pulmonares/etiología , Neoplasias Pulmonares/inducido químicamente , Carcinógenos
4.
Environ Res ; 212(Pt D): 113462, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35580667

RESUMEN

Multiple studies have demonstrated that cigarettes harbor bacterial pathogens. Yet, to our knowledge, there are no published data to date on whether or not these microorganisms can be aerosolized and transmitted to the respiratory tract of users. To address this knowledge gap, we characterized cigarette bacterial communities and evaluated whether or not they could be aerosolized in mainstream smoke. Filtered and unfiltered cigarettes were tested. Non-smoked tobacco leaf, enriched non-smoked tobacco leaf extract and enriched mainstream smoke extract samples (n = 144) were incubated on trypticase soy agar, and resulting bacterial colonies were sequenced. Total DNA was also extracted, followed by PCR amplification of the 16S rRNA gene, sequencing and analysis using UCHIME, QIIME and R packages. The predominant bacterial genera cultured from the mainstream smoke of unfiltered cigarettes were Bacillus, Terribacillus, Paenibacillus and Desulfotomaculum. Culturable bacteria were not recovered from the smoke of filtered products. However, sequencing data demonstrated no significant differences in bacterial community diversity in the smoke of filtered versus unfiltered cigarettes, suggesting that other non-culturable bacteria may be aerosolized in mainstream smoke as well. Our study provides novel evidence that tobacco-associated bacterial communities are viable, can be aerosolized in mainstream smoke, and could potentially be transferred to the oral cavity and respiratory tract of smokers.


Asunto(s)
Humo , Productos de Tabaco , Bacterias/genética , ARN Ribosómico 16S/genética , Humo/análisis , Nicotiana
5.
Chemosphere ; 301: 134735, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35489462

RESUMEN

Cigarette butts (CBs) are some of the most abundant waste items in the environment and may contain high levels of different toxic chemicals, such as aromatic amines (AAs). However, to this date, there is no comprehensive study on the role of CBs in the emission of AAs into the environment. The present study investigated for the first time the concentration levels of 10 primary aromatic amines (PAAs), including ANL, p-TOL, m-TOL, o-TOL, 2,6-DMA, o-ASD, 2-NA, 1-NA, 3-ABP, and 4-ABP that were measured and compared in unsmoked cigarette, freshly smoked CBs, and CBs collected from urban streets (named here aged CBs). The mean levels of ∑PAAs in different sample categories were statistically significantly different and the mean level order was as freshly smoked CBs > aged CBs > unsmoked cigarette with the values of 3.43, 2.12 µg g-1, and 0.28 µg g-1, respectively. The levels of ∑PAAs, ANL, o-ASD, 2,6-DMA, 2-NA, and ∑TOL dramatically increased by 12.26, 4.05, 8.46, 10.41, 4.78, and 28.84 times, respectively, right after smoking comparing the freshly smoked CBs samples and unsmoked cigarette. The results also showed a substantial decrease in the levels of PAAs (except o-ASD) in the aged CBs samples compared to freshly smoked CBs. The levels of ∑PAAs, o-ASD, 2,6-DMA, ∑TOL, ANL, 2-NA, 1-NA, and ∑ABP decreased 1.62, 1.09, 1.91, 3.20, 3.42, 2.63, 2.00, and 1.88 times, respectively. Considering the average PAAS content and estimated CBs littered worldwide every year, freshly smoked CBs can theoretically emit 2.9 tons of ∑PAAs into the environment annually. Considering other chemicals that may also be released into the environment via CBs (beside PAAs), we can consider CBs as a critical source of toxic compounds into the environment and water bodies.


Asunto(s)
Productos de Tabaco , Aminas , Humo , Fumar , Nicotiana
6.
Environ Res ; 209: 112866, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35134376

RESUMEN

In this study, the composition of mainstream smoke was investigated with an emphasis on a list of volatile organic compounds (VOCs: e.g., isoprene, acrylonitrile, methyl ethyl ketone, benzene, toluene, m-xylene and styrene) using the two types of flavor capsule cigarettes (FCCs, here coded as F1 and F2) in reference to one commercial, non-flavored (NF) and 3R4F cigarette. The concentrations of all the target compounds from FCCs were quantified under two contrasting conditions (i.e., with and without breaking the capsules). The effect of breaking the capsule was apparent in the FCC products with the enhancement of VOC levels, specifically between after and before breaking the capsules (e.g., 1.10-1.58 folds (benzene) and 1.30-1.53 folds (acetonitrile)). Such increases were apparent in both FCC samples if assessed in terms of the total amount of VOCs (TVOC): (1) F1 (from 2159 to 2530 µg cig-1 (p = 9.42 × 10-6)) and (2) F2 (from 1470 to 2014 µg cig-1 (p = 0.05)). In addition, these TVOC levels determined from the FCCs were 1.62- to 1.83- and 1.29- to 1.46-fold higher than those of the NF cigarette and the 3R4F cigarette, respectively. Thus, these FCC products are suspected to play a role as stronger sources of VOCs than the general cigarette products.


Asunto(s)
Productos de Tabaco , Compuestos Orgánicos Volátiles , Benceno/análisis , Humo , Nicotiana , Compuestos Orgánicos Volátiles/análisis
7.
Sci Total Environ ; 813: 152667, 2022 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-34963586

RESUMEN

The commercially sold cigarettes contain more than 7000 chemicals, and their combustion produces potential toxicants in mainstream smoke (MS), sidestream smoke (SS), secondhand smoke (SHS), thirdhand smoke (THS), and discarded cigarette butts (CBs). We conducted a systematic review of published literature to compare the toxicants produced in each of these phases of tobacco combustion (MS, SS, and CBs). The initial search included 12,301 articles, but after screening and final restrictions considering the aims of this review, 159 published studies were selected for inclusion. Additionally, SHS and THS are briefly discussed here. Overall, polycyclic aromatic hydrocarbons (PAHs) and other aromatic hydrocarbons have been represented in more studies than other compounds. However, metals and nitrosamines were detected in higher concentrations than other components in SS. The concentrations of most PAHs and other aromatic hydrocarbons in MS and SS are higher compared to concentrations found in CBs. Also, the concentrations of all the studied carbonyl compounds, aldehydes and ketones in SS and MS were higher than in CBs. The mean levels of alcohols and phenols in SS were higher than those reported for both MS and CBs. Tobacco toxicants are inhaled by smokers and transmitted to the environment through SS, SHS, THS, and discarded CBs. However, further studies are necessary to assess adverse effects of toxicants found in CBs and THS not only on human health, but also on the environment and ecosystems. The results of this review provide updated information on the chemical contents of MS, SS, SHS, THS, and CBs. It adds to the growing understanding that smoking creates major health problems for smokers and passive smokers, but also that it generates environmental hazards with consequences to the ecosystems and human health through discarded CBs, SHS, and THS exposure.


Asunto(s)
Productos de Tabaco , Contaminación por Humo de Tabaco , Ecosistema , Humanos , Humo/efectos adversos , Humo/análisis , Fumar , Nicotiana , Contaminación por Humo de Tabaco/efectos adversos , Contaminación por Humo de Tabaco/análisis
8.
ACS Appl Mater Interfaces ; 13(31): 37638-37644, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34324292

RESUMEN

The nicotine addiction problem is of great concern, particularly in adolescents. Notably, nicotine addiction drives humans to continue smoking. Notably, several diseases and disorders are caused by smoking. To date, various adsorbents have been proposed to develop a functionalization filter tip for reducing nicotine content in mainstream smoke. However, the nicotine adsorption efficiencies of most of the reported functionalization filter tips were not satisfactory, and their preparation process was complex and time-consuming. Herein, we demonstrate a highly active and adsorbing filter tip for cigarettes, fabricated by decorating polydopamine (PDA) on the surface of a commercial filter tip in situ. The PDA coating on the filter tip was obtained by the self-polymerization of dopamine (DA) within 16 h, which was quicker and easier than the preparation processes of other reported functionalized filter tips. Significantly, the PDA-decorated filter tip had a nicotine adsorption efficiency as high as ∼95%, which was much higher than most of the commercial filter tips.


Asunto(s)
Fraccionamiento Químico/instrumentación , Indoles/química , Nicotina/aislamiento & purificación , Polímeros/química , Contaminación por Humo de Tabaco , Adsorción , Fraccionamiento Químico/métodos , Nicotina/química , Productos de Tabaco
9.
Int J Nanomedicine ; 16: 2203-2217, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33762821

RESUMEN

BACKGROUND: It is well known that smoking is harmful to health; however, it can also ameliorate anxiety. To date, it is unclear whether any nanoparticles found in cigarette mainstream smoke (CS) contribute to this effect. AIM: The aim of this study was to assess the particle composition of CS to identify novel anti-anxiety components. METHODS: Carbon dots (CDs) from CS (CS-CDs) were characterised using high-resolution transmission electron microscopy, Fourier-transform infrared, ultraviolet, fluorescence, X-ray photoelectron spectroscopy, X-ray diffraction and high-performance liquid chromatography. The anti-anxiety effects of CS-CDs in mouse models were evaluated and confirmed with the elevated plus maze and open-field tests. RESULTS: The quantum yield of CS-CDs was 13.74%, with a composition of C, O, and N. In addition, the surface groups contained O-H, C-H, C=O, C-N, N-H, C-O-C, and COO- bonds. Acute toxicity testing revealed that CS-CDs had low in vitro and in vivo toxicity within a certain concentration range. The results of the elevated plus maze and open-field tests showed that CS-CDs had a significant anti-anxiety effect and a certain sedative effect in mice. The mechanism of these effects may be related to the decrease in glutamate levels and promotion of norepinephrine production in the mouse brain, and the decrease in dopamine in mouse serum due to CS-CDs. CONCLUSION: CS-CDs may have anti-anxiety and certain sedative effects. This study provides a new perspective for a more comprehensive understanding of the components, properties, and functions of CS. Furthermore, it offers a novel target for the development of smoking cessation treatments, such as nicotine replacement therapy.


Asunto(s)
Conducta Animal , Carbono/química , Fumar Cigarrillos/efectos adversos , Sistema Endocrino/metabolismo , Neurotransmisores/metabolismo , Puntos Cuánticos/química , Agua/química , Hormona Adrenocorticotrópica/sangre , Animales , Ansiedad/sangre , Ansiedad/patología , Encéfalo/metabolismo , Encéfalo/patología , Cromatografía Líquida de Alta Presión , Corticosterona/sangre , Hormona Liberadora de Corticotropina/sangre , Dopamina/sangre , Masculino , Ratones , Ratones Endogámicos ICR , Espectroscopía de Fotoelectrones , Puntos Cuánticos/ultraestructura , Células RAW 264.7 , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Pruebas de Toxicidad Aguda , Difracción de Rayos X
10.
Toxicol Rep ; 8: 405-410, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33717993

RESUMEN

Nitromethane is a volatile organic compound categorized as a Group 2B carcinogen by the International Agency for Research on Cancer. It has been detected in mainstream cigarette smoke, but few reliable methods have been reported for accurate quantification. We developed, a sensitive, selective, fully validated method for the targeted determination of nitromethane in mainstream tobacco smoke in ten U.S. domestic brands and two quality control materials (3R4F and CM6). The vapor phase portion of machine-generated cigarette mainstream smoke, under modified ISO 3308:2000 regime (ISO) and modified intense regime (HCI), from single cigarettes was collected using airtight polyvinylfluoride sampling bags. The bags' contents were extracted using methanol containing an isotopically labeled internal standard followed by gas chromatography-tandem mass spectrometry. This approach is sufficiently sensitive to measure nitromethane levels in the nanogram range, with a method limit of detection of 72.3 ng/cig. Within-product variability estimated from the replicate analysis of 10 products ranged from 4.6%-16.3% (n = 6) over the two different smoking regimes, and method reproducibility estimated from two products used as quality control materials (3R4F and CM6) yielded intermediate precision values ranging from 16.6 to 20.8% (n = 20). Under HCI, nitromethane yields in machine-generated cigarette smoke from ten different domestic cigarette products ranged from 3.2 to 12 µg/cig; under ISO yields ranged from 1.6 to 4.9 µg/cig under standardized smoking machine conditions. Nitromethane yields are related to both the smoke regime (blocking of vent holes, puff duration and puff volume) and the heterogeneity of tobacco mixtures. This method provides a selective and fully validated technique to accurately quantify nitromethane in mainstream cigarette smoke, with minimal waste generation. It is an improvement over previous methods with regards to specificity, throughput, and simplicity of the sample collection process.

11.
Environ Sci Pollut Res Int ; 28(5): 5205-5217, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32964389

RESUMEN

A green methodology was developed for the analysis of ten heterocyclic aromatic amines (HAAs) in biomass samples from cigarette combustion such as mainstream smoke, paper ashes, as well as tobacco and paper wraps. The cellulose filter used for sample collection was also evaluated. This strategy was based on ultrasound-assisted extraction (UAE) associated with a solid-phase extraction procedure employing multi-walled carbon nanotubes (MWCNTs-SPE) as a cleanup step followed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Under optimal experimental conditions, the linearity of the method was in the range from 0.08 to 160 ng cig-1, with correlation coefficients (R2) higher than 0.991. The limits of detection resulted to be between 0.03 and 0.63 ng cig-1. Concentrations of the HAAs in the mainstream smoke were from 5.7 to 145.2 ng cig-1 and in paper ashes from 0.1 to 0.6 ng cig -1, while in tobacco were between 1.0 and 38.5 ng cig-1. Meanwhile, no HAA contribution was observed in the case of paper wraps and the filter used for sample collection. The knowledge of the presence and the concentration levels of the selected HAAs in each cigarette's physical component after its combustion is essential to understand the formation processes and contribution during cigarette burning. Besides, this is the first report about the presence of some HAAs in the proposed samples. Finally, a comparative study was employed to classify the sustainability of several recent approaches for HAA extraction from cigarette combustion samples using Green Certificate as a metric tool.


Asunto(s)
Nanotubos de Carbono , Productos de Tabaco , Aminas , Biomasa , Espectrometría de Masas en Tándem , Nicotiana
12.
Talanta ; 217: 121060, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32498828

RESUMEN

Particulate matter from mainstream smoke (MSS) is significantly hazardous when inhaled into the human body. An ambient ionization mass spectrometric method, direct analysis in real time mass spectrometry (DART-MS), was applied to rapidly and simultaneously measure multiple particulate components in MSS. A variety of compounds were obtained in seconds, where different types of cigarettes and different solvent extracts generated distinct chemical constituents as validated by principle component analysis. Chemical formula assignment and compound identification were based on accurate m/z values with mass errors <10 ppm. Quantitation of nicotine was achieved using an isotope internal standard with DART-MS. Method validation with chromatographic-MS analysis further proved the advantages of DART-MS with respect to analysis speed and operational simplicity for the direct evaluation of complex samples. DART-MS is feasible for the rapid acquisition of cigarette fingerprints for quality control as well as for quantitative assessment of carcinogens for harm reduction.

13.
Toxicol Rep ; 6: 222-231, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30886823

RESUMEN

A new Kentucky reference cigarette, 1R6F, has been manufactured to replace the depleting 3R4F reference cigarette. The 3R4F Kentucky reference cigarettes have been widely used as monitor or comparator cigarettes for mainstream smoke analysis and in vitro and in vivo toxicological data of cigarettes and novel tobacco products. Both reference cigarettes were analyzed in the same laboratory during the same period of time with the goal of performing a comparison of 3R4F and 1R6F. On the basis of the results obtained from aerosol chemistry and in vitro assays, we consider that the 1R6F reference cigarette is a suitable replacement for the 3R4F reference cigarette as a comparator/monitor cigarette. Its specific use as a comparator for novel tobacco products was checked on the basis of a comparative test with the Tobacco Heating System 2.2 as an example.

14.
Anal Bioanal Chem ; 411(13): 2961-2969, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30877347

RESUMEN

This paper proposed a newly developed heart-cutting two-dimensional supercritical fluid chromatography-high-performance liquid chromatography system coupled to tandem mass spectrometry (SFC-HPLC-MS/MS) for the determination of four tobacco-specific nitrosamines (TSNAs) in cigarette mainstream smoke. The orthogonality of five SFC columns and two HPLC columns was evaluated. The 1-AA column was applied for the first dimensional (1D) SFC separation to isolate the target compounds from the complex cigarette smoke matrices, and a trapping column in conjunction with an isocratic pump was employed to capture the 1D elutes. Then, the trapped 1D elutes were transferred into the C18 column through a two-position/six-port valve for the second dimensional (2D) analysis. The ion suppression was significantly reduced by the established SFC-HPLC system; meanwhile, the matrix interferences were eliminated as the results demonstrated. A dynamic range between 0.1 and 20 ng/mL was achieved with LOQs of 0.72 µg/cig for N-nitrosonornicotine (NNN), 0.66 µg/cig for nicotine-derived nitrosamine ketone (NNK), 0.81 µg/cig for N-nitrosoanatabine (NAT), and 0.39 µg/cig for N-nitrosoanabasine (NAB). All the results revealed that the presented method exhibited good repeatabilities and recoveries and could be used as a rapid and reliable approach for routine analysis of TSNAs in mainstream smoke.

15.
Regul Toxicol Pharmacol ; 103: 181-188, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30710578

RESUMEN

[Introduction] Seven smoke constituents, including hydrogen cyanide (HCN), ammonia (NH3), phenol, benzo[α]pyrene (B[a]P), carbon monoxide (CO)¸ crotonaldehyde, and 4-(methylnitrosamino)-1- (3-pyridyl)-1-butanone (NNK), are proposed be the most relevant constituents for smoking-related diseases. [Methods] Different combinations of leaf stalk positions, varieties and locations were used to create variable chemistry of cigarette filler and smoke. Experimental cigarettes were measured for emission level of seven smoke toxicants and content of seventy-three filler components. [Results] The ranges of coefficient of variation (CV) for seven smoke toxicants were 15.43%-43.15%. The emission pattern of NNK and crotonaldehyde were different from that of other five smoke toxicants. Most of the seven smoke toxicants were influenced in following order: stalk position > location > variety. The leaf constitutes closely correlated with seven smoke toxicants were analyzed. [Conclusions] The results showed that seven toxicants were significantly influenced by leaf position and location, and closely correlated with leaf components, such as potassium, malate and alkaloid contents. The results provide useful and comprehensive information on the affecting factors and correlating leaf constituents for the variations of seven smoke toxicants.


Asunto(s)
Sustancias Peligrosas/análisis , Nicotiana/química , Hojas de la Planta/química , Humo/análisis , Productos de Tabaco/análisis , Sustancias Peligrosas/química
16.
Regul Toxicol Pharmacol ; 94: 152-162, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29408505

RESUMEN

A total of 38 hazardous constituents in mainstream cigarette smoke of low-yield cigarettes sold in Korea were selected and analyzed using established methods. Risk calculations were performed using risk algorithms employed in previous studies and Korean population-based exposure parameters. The median cumulative incremental lifetime cancer risk of male smokers could vary from 828 × 10-6 to 2510 × 10-6, and that of female smokers could range from 440 × 10-6 to 1300 × 10-6, depending on the smoking regimens. The median hazard index as the sum of hazard quotients of male smokers varied from 367 to 1,225, and that of female smokers varied from 289 to 970, depending on the smoking regimens. The sensitivity analysis for this risk assessment indicated that the constituent yields in mainstream cigarette smoke, average number of cigarettes smoked per day or year, and mouth-spill rate are the main risk factors. Statistical positive correlations between the average daily dose calculated by the exposure algorithm used in this study for individual smokers and biomarkers verified the reliability of this assessment. It could be concluded that inhalation of the constituents present in the mainstream of low-yield cigarettes has significant cancer and non-cancer health risks, although its effect on risk reduction is still unknown under the fixed machine-smoking conditions.


Asunto(s)
Exposición por Inhalación/efectos adversos , Neoplasias/inducido químicamente , Nicotiana/efectos adversos , Humo/efectos adversos , Fumar/efectos adversos , Productos de Tabaco/efectos adversos , Carcinógenos/toxicidad , Femenino , Humanos , Pulmón/metabolismo , Masculino , República de Corea , Medición de Riesgo , Humo/análisis , Fumadores
17.
Tob Regul Sci ; 3(Suppl 1): S31-S40, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28944278

RESUMEN

OBJECTIVE: Although most cigarillos and little cigars smokers also smoke cigarettes (dual use), there are few studies comparing toxicant exposure and smoking behavior in cigars and cigarettes. METHODS: Two groups of dual users smoked their usual brand of cigarette and either a Winchester unflavored little cigar (N = 21) or a Black & Mild cigarillo (N = 23). Acute exposure of nicotine and exhaled carbon monoxide (CO) and puffing topography parameters were collected. Individual cigar puffing data were used to machine-replicate smoking for analysis of volatile organic compounds (VOC) and semi-volatile organic compounds (SVOC) in mainstream smoke. RESULTS: There were significant differences in puff topography, plasma nicotine and exhaled CO after cigarettes, little cigars, and cigarillos. Puff topography differences between cigarillos and cigarettes were due to the difference in the size of the article. Mainstream cigar and cigarette smoke was qualitatively similar; the yield was dependent on the smoking behavior. When smoke yield was adjusted for weight of tobacco burned or puff volume, exposure differences decreased. CONCLUSIONS: There is a wide range of delivery of both SVOC and VOC components of cigar and cigarillo smoke. The difference in exposure is largely dependent on the article size and the amount consumed.

18.
Tob Regul Sci ; 3(1): 81-94, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28220149

RESUMEN

OBJECTIVE: Our objective was to characterize mainstream smoke constituent deliveries from SPECTRUM variable nicotine research cigarettes under 2 machine smoking regimens. SPECTRUM cigarettes are manufactured by the 22nd Century company for the National Institute on Drug Abuse, National Institutes of Health to contain varying (including reduced) levels of nicotine. METHODS: Mainstream smoke constituent deliveries of "tar," nicotine, carbon monoxide, tobacco-specific nitrosamines (N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)), benzo[a]pyrene, aromatic amines, and carbonyls were analyzed in 23 varieties of SPECTRUM cigarettes using ISO 17025 accredited methods. RESULTS: Data are presented as means and standard deviations of 5 replicates for all analytes. CONCLUSIONS: Under the ISO smoking regimen, mean levels of many smoke emissions for SPECTRUM varieties were comparable to the 3R4F research cigarette. Calculated SPECTRUM elasticity ranged from 1.6 to 4.0. Accordingly, under intense machine smoking conditions differences in emissions of SPECTRUM cigarettes were apparent. In addition, NNN increased with smoke nicotine while the same rate of change was not seen for NNK. It is important to monitor levels of chemicals of public health concern and regulatory interest as technologies emerge to reduce levels of nicotine or other targeted chemicals in tobacco products.

19.
Toxicology ; 357-358: 1-10, 2016 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-27237783

RESUMEN

Epidemiology studies suggest that maternal smoking and passive smoking have strongly resulted in the occurrence of congenital heart defects (CHD) in offspring. Cigarette smoke (CS) can be divided into mainstream smoke (MS) and sidestream smoke (SS); CS chemistry study indicates that significant differences exist in the composition of MS and SS. Therefore, MS and SS were suspected to process toxicity dissimilarly. However, much less was known about the difference in the developmental effects induced by MS and SS. In the current study, heart development was mimicked by mouse embryonic stem cells (ESCs) differentiation. After MS and SS exposure, by tracing the bone morphogenetic protein (BMP)-Smad4 signalling pathway, interruption of downstream gene expression was observed, including Gata4, Mef2c and Nkx2.5, as well as myosin heavy chain and myosin light chain. Specifically, SS caused inhibition of Gata4 expression, even at non-cytotoxic concentration. Further, SS-induced hypoacetylation in promoter regions of Gata4 reflected the orchestration of CS-gene modulation-epigenetic regulation. Even though SS induced apoptosis in ESC-derived cardiomyocytes, the partial clearance in cells with down-regulated Gata4 caused these cells to survive and undergo further differentiation, which laid potential risk for abnormal heart development. These data uncovered the difference between MS and SS on heart development preliminarily.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Células Madre Embrionarias de Ratones/efectos de los fármacos , Humo/efectos adversos , Fumar/efectos adversos , Contaminación por Humo de Tabaco/efectos adversos , Animales , Apoptosis/efectos de los fármacos , Proteínas Morfogenéticas Óseas/metabolismo , Supervivencia Celular/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Epigénesis Genética , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Cardiopatías Congénitas/etiología , Ratones , Ratones Endogámicos C57BL , Células Madre Embrionarias de Ratones/citología , Embarazo , Transducción de Señal/efectos de los fármacos , Proteína Smad4/metabolismo , Nicotiana
20.
Regul Toxicol Pharmacol ; 75: 27-34, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26739812

RESUMEN

Based on encouraged development of potential reduced-exposure products (PREPs) by the US Institute of Medicine, casings (glucose and peptides) added treatments (CAT) and enzymatic (protease and xylanase) hydrolysis treatments (EHT) were developed to study their effect on alkaloids reduction in tobacco and cigarette mainstream smoke (MS) and further investigate the correlation between sensory attributes and alkaloids. Results showed that the developed treatments reduced nicotine by 14.5% and 24.4% in tobacco and cigarette MS, respectively, indicating that both CAT and EHT are potentially effective for developing lower-risk cigarettes. Sensory and electronic nose analysis confirmed the significant influence of treatments on sensory and cigarette MS components. PLSR analysis demonstrated that tobacco alkaloids were positively correlated to the off-taste, irritation and impact attributes, and negatively correlated to the aroma and softness attributes. Additionally, nicotine and anabasine from tobacco leaves positively contributed to the impact attribute, while they negatively contributed to the aroma attribute (P<0.05). Meanwhile, most alkaloids in cigarette MS positively contributed to the impact and irritation attributes (P<0.05). Hence, this study paved a way to better understand the correlation between tobacco alkaloids and sensory attributes.


Asunto(s)
Alcaloides/análisis , Nicotiana/química , Hojas de la Planta/química , Contaminación por Humo de Tabaco/análisis , Nariz Electrónica , Endo-1,4-beta Xilanasas/química , Femenino , Glucosa/química , Humanos , Hidrólisis , Masculino , Odorantes , Péptido Hidrolasas/química , Péptidos/química , Gusto
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