• Proceedings of the Korean Society of Tobacco Science Conference
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• 2000.05a
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• pp.12-21
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• 2000

The smoke from a burning cigarette is classified as mainstream, which is the smoke inhaled by the smoker during a puff, and sidestream, which is defined by ISO 10185 as all smoke which leaves a cigarette during the smoking process other than from the butt end. Most of the sidestream smoke is generated during static burn, that is, in between puffs. The amount of sidestream smoke generated by a cigarette depends on the cigarette construction, tobacco blend, and properties of the cigarette paper, The main paper properties affecting sidestream smoke generation are: porosity, basis weight, type and amount of filler, type and amount of burn additive.Sidestream smoke is composed of a visible phase (small liquid droplets) and an invisible phase (gaseous molecules). This paper focuses on the visible portion of the sidestream smoke. Optical methods, which are based on the relationship between light scattering and density of the rising plume of smoke, have been used successfully by the industry. However, the present trend is to use gravimetric methods where the particulate matter is captured on a Cambridge(R) filter pad and weighed. The gaseous portion of the sidestream smoke, which does not contribute to the visible sidestream smoke, passes through the Cambridge filter pad.Sidestream smoke reduction is achieved by modifying certain mass transport processes occurring in a smoldering cigarette. There are four main pathways for reducing sidestream smoke: A) less tobacco burned, B) slower rate of tobacco combustion, C) more efficient trapping of smoke by the cigarette paper, and D) more complete combustion of tobacco. This paper discusses how the physical properties of paper and cigarette construction affect sidestream smoke reduction via the above four mechanisms.

• Toxicological Research
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• v.31 no.1
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• pp.41-48
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• 2015

Owing to the increase in price of cigarettes in Korea, herbal cigarettes have received increasing attention as a non-smoking aid; however, its safety has hardly been studied. We analyzed some of the toxic components in the mainstream smoke of herbal cigarettes, performed a mutagenicity test on smoke condensates for safety assessment, and compared the results with the corresponding values of a general cigarette with the same tar content. Herbal cigarette "A" was smoked using automatic smoking machine under ISO conditions in a manner similar to general cigarette "T". The tar content measured was higher than that inscribed on the outside of a package. The mainstream smoke of herbal cigarette "A" did not contain detectable levels of tobacco-specific nitrosamines and nicotine. Carbon monoxide and benzo(${\alpha}$)pyrene contents in herbal cigarette "A" were higher than those in the general cigarette "T". The phenolic contents such as hydroquinone, resorcinol, and catechol in herbal cigarette "A" were higher than those in the general cigarette "T", but cresol contents in herbal cigarette "A" were lower than those in the general cigarette "T". The content of aromatic amines such as 4-aminobiphenyl in herbal cigarette "A" was higher than that in the general cigarette "T"; however, this difference was not statistically significant. On the other hand, 1-aminonaphthalene, 2-aminonaphthalene, and 3-aminobiphenyl contents in herbal cigarette "A" were lower than those in the general cigarette "T". The smoke condensates of herbal cigarette "A" exhibited a higher mutagenic potential than the condensates from the general cigarette "T" at the same concentration. We concluded that the mainstream smoke of herbal cigarette contains some toxic components, the smoke condensates of herbal cigarettes are mutagenic similar to general cigarette because of combustion products, and that the evaluation of the chemical and biological safety of all types of herbal cigarettes available on the market.

• Journal of the Korean Society of Tobacco Science
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• v.18 no.2
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• pp.160-169
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• 1996

Effect of cigarette smoke exposure on 1-methyl-4-phpnyl-1,2,3,6-tetrahydro-pyidine (Mm)-induced neurotoxicity was investigated in C57BL6 mice. Cigarette smoke exposure of mice to the mainstream smoke generated from 15 cigarettes for 10 mins per day, 5 days per week, for fi weeks, effectively attenuated the decline both in the level of striatal dopamine and the number of brrosine hydros:ylase-positive ceils in the brain caused by MPTP treahent. Exposure to cigarette smoke significantly decreased monoamine oxidate B activity in the cerebral cortex and cerebellum. The activity of brain antioxidant enzymes such as catalase, glutathione peroxidase, and Cu, Zn-superoxide dismutase, was not changed by cigarette smoke exposure or MPTP treatment. Sulfhydryl compounds content in all brain regions except for the striatum was uniquely increased by MPTP treatment, however, such an effect of MPTP was not observed in mice exposed to cigarette smoke. These results suggest that cigarette smoke exposure inhibits MPTP-induced neurotoxicity without influencing free radical metabolism in the brain of mice. This protective effect of cigarette smoke seems to be closely related with the decreased activity of brain monoamine oxidase H. Key words : cigarette smoke exposure, dopamine, monoamine oxidase B, antioxidant enzywles, MPTP.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.1
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• pp.40-46
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• 2012

Cigarette smoking is known to be associated with various chronic pulmonary and cardiovascular diseases ranging from inflammation to cancer. Not only first-hand smoke but also second-hand smoke is suggested to be a factor of health risk. This study was to investigate whether Platycodi Radix extract administration would alter oxidative stress in lung leading to protection of cigarette smoke-induced lung damage. Sprague-Dawley rats were randomly divided into 3 groups; Intact, Smoke+PR and Smoke+Vehicle. In Smoke+PR and Smoke+Vehicle group, the exposure to cigarette smoke was performed for 15 min/day for 4 weeks in ventilated smoking chamber. The Platycodi Radix extract and saline were orally administrated to Smoke+PR and Smoke+Vehicle group each. The rats of Intact group were just kept in ventilated chamber without cigarette smoke. After the experiment for 4 weeks, the lung tissues were collected for histological observation and immunohistochemistry. In Results, airspace enlargement and goblet cell hyperplasia were observed after 4 weeks' exposure to cigarette smoke. Whereas, the oral administration of Platycodi Radix extract for 4 weeks reduced airspace enlargement and goblet cell hyperplasia. Moreover, the alterations of BAX/Bcl-2 proteins in lung tissues were observed. These results suggest that Platycodi Radix extract ameliorates lung damage in cigarette smoke-exposed rats and has protective effects on second-hand smoke injury.

• Toxicological Research
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• v.22 no.3
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• pp.245-251
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• 2006

Nitric oxide(nitrogen monoxide, NO) plays important physiological roles, but excessive generation can be toxic. NO is present in cigarette smoke at up to 1,000 ppm, and probably represents one of the greatest exogenous sources of NO to which humans are exposed. We investigated whether cigarette smoking reduces the production of endogenous NO and whether it influences the action of lipopolysaccharide(LPS) to induce nitric oxide synthase activity in mouse brain. Mice(C57BL6/J) were exposed to cigarette smoke for 8 weeks. LPS was injected intraperitoneally in single or combination with the exposure to cigarette smoke. Six hours after the injection of LPS, mice were sacrificed and sera and brains were collected. Serum concentrations of nitrate and nitrite were not charged by 4-week smoke exposure, but were significantly increased by 6 and 8 weeks of smoke exposure. Interestingly, cigarette smoke reduced the elevation in serum nitrate and nitrite concentrations produced by LPS after 4-week smoking exposure. NO synthase(NOS) activity in brain was upregulated by LPS-administration. However, cigarette smoke exposure remarkably and consistently decreased the LPS-induced activity in mouse brain. This result suggests that cigarette smoking may affect against overproduction of the endogenous NO by LPS through the inhibition of NOS activity induced by LPS in brain or by modulation of the LPS action for the induction of NOS activity. We also suggest the possibility that the exogenous NO evolved in cigarette smoke enables feedback inhibition of NOS activity or other possibility that it attenuates the toxicity of endotoxin LPS in vivo by unknown mechanisms, which should be further studied.

• Journal of the Korean Society of Tobacco Science
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• v.36 no.1
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• pp.20-25
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• 2014

As part of a balanced testing battery, subchronic inhalation studies on rats are performed to ensure that proposed cigarette modifications do not increase the toxicity of smoke and to demonstrate any instances where a modification may actually contribute to harm reduction. For subchronic inhalation studies with aerosols, the OECD suggests an exposure regimen of 6 hours/day (OECD Guideline 413, 1981), but alternative regimens have also been published: 1 hour/day and $2{\times}1$ hour/day. The aim of this study was to validate a rodent nose-only exposure system for the assessment of inhalation toxicity of cigarette smoke. In this study, cigarette smoke exposure system is consisted of cigarette smoke generator, smoke concentration adjusting system, and 20-port nose-only exposure system. Male SD rats were exposed for 35 days ($2{\times}1$ hour/day) to 3R4F Reference cigarette smoke and analysed major monitoring items of OECD Gudeline 413. WTPM, was measured in the test atmosphere, respiratory function (Buxco Biosystems) during exposure, postexposure urinary exposure biomarkers and alveolar neutrophiles in BAL fluid (Day 35) were evaluated. Validation demonstrated steady WTPM ($257{\pm}20ug/L$, $502{\pm}27ug/L$) and spatial uniformity (<10%). Nose port temperature ($22{\sim}26^{\circ}C$ and RH (45~75%) were acceptable over 35 days. Reductions in respiratory rate and minute volume and increase in the neutrophiles in BALF and the urinary exposure biomarkers were observed cigarette smoke dose dependently. This validation and 35-day inhalation study has shown that the rodent nose-only exposure system may be useful in the inhalation toxicity assessment of cigarette smoke.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.99-107
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• 1998

Numerous studies have demonstrated a negative association between cigarette smoking and Parkinson's disease. The present study was undertaken to investigate whether chronic exposure of mice to cigarette smoke a(footed the metabolism of 1-methyl-1113,6-tetrahydro-pyridine (MPTP) by cytochrome P4SO (P-450) or flavin-containing monooxygenase (FMO) in the hepatic microsomes of C57BL6/J mice. Adult male C57BL6/J mice were exposed to mainstream smoke generated from 15 cigarettes for 10 min a day and 5 day per week for 6 weeks. MPTP (10 mg/kg body weight) was administered to mice by subcutaneous injection for 6 consecutive days. Microsolnal P-450 content was increased by MPTP, smoke exposure, or both, but NADPH cytochrome P-450 reductase activity was rather decreased by the same treatments. The activities of benzo(a)pyrene hydroxylase, 7-ethoxycoumarin O-deethylase and ethoxyresorufin O-deethylase were significantly increased by the exposure of cigarette smoke, but were not or little affected by MPTP treatment. Benzphetamine N-demethylase activity was not affected either by MPTP treatment or by cigarette smoke exposure, but it was significantly increased by the combined MPTP treatment with cigarette smoke exposure, showing their synergic effect for the induction of the enzyme activity. Interestingly, in vitro studies of hepatic FMO and P-450 system both O-oxygenation and N-demethylation of MPTP were increased in the smoke-exposed or in the MPTP-treated mice. These results suggest that the enhancement in the N-demethylation as well as O-deethylation of P-450 system and in the N-oxygenation of FMO activity by cigarette smoke exposure in mouse liver may contribute to attenuating the neurotoxic effects of MPTP on the nigrostriatal dopaminergic neurons.

• Journal of the Korean Society of Tobacco Science
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• v.27 no.1 s.53
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• pp.51-58
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• 2005

The objective of this study was to evaluate the effect of cigarette filter on in vitro cytotoxicity of cigarette mainstream smoke from the cigarette. In this work, we used 3 types of cigarettes included non-filtered 2R4F cigarette, cellulose acetate-filtered 2R4F cigarette, and carbon dual-filtered 2R4F cigarette which was made from original 2R4F by replacing with an acetate filter containing carbon. The cytotoxicity of both the cigarette smoke condensate (CSC), which was collected in Cambridge filter pad, and the gas/vapor phase (GVP), which was bubbled through in phosphate-buffered saline in a gas-washing bottle, was determined using a neutral red uptake assay with CHO-K1 cells. With regard to cytotoxicity when calculated on an equal puff basis, the cytotoxicity of CSC from the filtered cigarettes was lower than that of the non filtered cigarette. Also, $EC_{50}$ vlaue of GVP from carbon filter cigarette was 40.9 puff/L, indicating the cytotoxicity to be $20\%$ lower than that of the CA filter cigarette. The cytotoxicity of the GVP was correlated to the several vapor phase components (formaldehyde, acetaldehyde, acetone, acrolein, crotonaldehyde and MEK). In conclusion, carbon filter, which significantly reduced the amount of carbonyl compounds in mainstream cigarette smoke, results in significant reductions in the cytotoxicity potential of the smoke.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.115-123
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• 1998

The semi-volatile fraction of cigarette mainstream smoke contains the most important aroma and taste that enhance smoke flavor. The components in mainstream smoke were analysed for commercially available cigarettes. To compare the semi-volatile components delivered from mainstream smoke of domestic cigarette with imported cigarette, we analyzed three types of filter cigarettes such as cellulose acetate mono filter, carbon dual filter and slim filter cigarette. Mainstream smoke was collected with a combination of Cambridge filter pad and liquid trap containing a small amount of acetone cooled by dry ice-methanol. We have identified 43 components from mainstream smoke by GC and GC/MS and found that benzene, toluene, 4-hydroxy-4-methyl-2-pentanone, 5-methyl-2-furaldehyde, acetic acids nicotine and triacetin were the main peaks in mainstream smoke. Also we have compared the relative amounts of semi-volatile compounds delivered from the domestic and imported cigarettes with three different filters. From the results of this study, the relative amounts of limonene, acetic acid, 5-methyl-Lfuraldehyde delivered from the imported cigarettes were generally higher than those of the domestic one's.

• Journal of the Korean Society of Tobacco Science
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• v.3 no.2
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• pp.123-128
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• 1981

For evaluating the cigarette smoke quality of nonblended and commercial cigarettes, four modified smoke quality indexes were deduced from considering the reactivity of the thiol group in cystine (SH value) with the cigarette smoke constituents, and from the maximum limited contents of tar. nicotine, and carbon monoxide for the less harmful cigarettes. These results were discussed with respect to correlation coefficients between the indexes and tar/nicotine ratio which had been known reliable for smoke quality evaluation. Among the three indexes, the SH/[(N/O.6) +($\frac{C+T}{8}$)] index was found to be the most reliable and applicable.