Maximum yields might improve public health--if filter vents were banned: a lesson from the history of vented filters

Filter ventilation is the dominant design feature of the modern cigarette that determines yields of tar, nicotine, and carbon monoxide on smoking machine tests. The commercial use of filter ventilation was precipitated by the 1964 United States Surgeon‐General's report, further advanced by the adoption of an official Federal Trade Commission test in 1967, and still further advanced by the inclusion of a gas phase (carbon monoxide) measure in 1979. The first vented‐filter brand on the market in the United States (Carlton) in 1964 and the second major vented‐filter brand (True) in 1966 illustrate this. Ultimately, filter ventilation became a virtually required way to make very low tar cigarettes (less than 10 mg or, even more so, less than 5 mg tar). The key to the lower tar cigarette was not, in effect, the advanced selective filtration design characteristics or sophisticated tobacco selection or processing as envisioned by experts (although these techniques were and are used); the key to the very much lower tar cigarette was simply punching holes in the filter. We propose that the banning of filter vents, coupled with low maximum standard tar, nicotine, and carbon monoxide yields, would contribute to making cigarettes much less palatable and foster smoking cessation or the use of clearly less hazardous nicotine delivery systems. It may be necessary to link low maximum yields with the banning of filter ventilation to achieve public health benefit from such maxima.     

Effects of low nicotine content cigarettes on smoke intake.

Cigarettes with selective reductions in nicotine delivery have been considered as potential tools to prevent or treat nicotine dependence or to reduce harm by virtue of reduced nicotine and nitrosamine delivery. An important question is whether individuals smoke these products more intensively, as has been shown to occur with ventilated-filter cigarettes. To investigate this issue, we compared conventional highly ventilated filter cigarettes, having very low tar and nicotine yields when smoked by Federal Trade Commission method (1 mg tar, 2 mg carbon monoxide [CO],.2 mg nicotine), with low nicotine content cigarettes, manufactured from a genetically modified strain of tobacco, which had higher tar but lower nicotine yield (14 mg tar, 13 mg CO,.02 mg nicotine). A total of 16 cigarette smokers participated in two 8-hr sessions (order counterbalanced) during which they smoked each type of cigarette ad libitum. Expired-air CO, plasma nicotine, and smoking topography measures were collected. Subjects showed significant increases in smoking when using the highly ventilated filter cigarettes, and puff volume was significantly greater than with the low nicotine content cigarettes. Subjects achieved an expired-air CO level 74% as high as with the low nicotine content cigarettes; the latter produced CO levels similar to those measured at baseline when subjects smoked their habitual brands of cigarettes. Plasma nicotine levels obtained when subjects smoked the highly ventilated filter cigarettes also were significantly higher than when they smoked the low nicotine content cigarettes. These results indicate that the delivery of substantial amounts of smoke, with selective reductions in nicotine yield, appears to prevent compensatory smoking behavior. Further studies should determine whether similar results are obtained in naturalistic environments.     

Determination of tar, nicotine, and carbon monoxide yields in the mainstream smoke of selected international cigarettes

Objective: Survey of nicotine, tar, and carbon monoxide (CO) smoke deliveries from 77 cigarette brands purchased in 35 countries was conducted using a standardised machine smoking method. The goal of this study was to determine regional variations and differences in the tar, nicotine, and CO smoke yields of a cigarette brand manufactured by a leading transnational corporation and of non-US locally popular cigarette brands.

Design: The majority of the cigarettes were purchased in each of the participating countries by delegate members of the World Health Organization and forwarded to the Centers for Disease Control and Prevention for analysis. Smoke deliveries were determined using a standardised smoking machine method and subsequent gravimetric and gas chromatography analysis.

Results: The smoke deliveries varied widely. Mainstream smoke deliveries varied from 6.8 to 21.6 mg tar/cigarette, 0.5 to 1.6 mg nicotine/cigarette, and 5.9 to 17.4 mg CO/cigarette. In addition to the smoke deliveries, the cigarettes were examined to determine physical parameters such as filter composition, length, and ventilation levels.

Conclusion: Analysis of the smoke deliveries suggested that cigarettes from the Eastern Mediterranean, Southeast Asia, and Western Pacific WHO regions tended to have higher tar, nicotine, and CO smoke deliveries than did brands from the European, American, or African WHO regions surveyed.

     

Roll-your-own smoke yields: theoretical and practical aspects

OBJECTIVE—To identify the key parameters that influence smoke yields from roll-your-own (RYO) cigarettes and to compare smoke yields of cigarettes made under laboratory conditions with those made by habitual RYO consumers.
DESIGN AND SETTING—One-way parametric variations in the laboratory-based production of RYO cigarettes complemented by a consumer survey conducted in a busy street at Romford, Essex, United Kingdom.
SUBJECTS—26 habitual RYO consumers.
MAIN OUTCOME MEASURES—Cigarette weights, puff numbers, and yields (carbon monoxide, nicotine, and tar).
RESULTS—Smoke yields vary for specimen changes in weight of tobacco used, paper porosity, and the incorporation of a filter in the cigarette. Yields of cigarettes produced by 26 RYO smokers ranged from 9.9 to 21.0 mg tar per cigarette and from 0.9 to 1.8 mg nicotine per cigarette, and were generally lower than yields of laboratory-produced RYO cigarettes.
CONCLUSIONS—Laboratory studies can provide useful information concerning the parameters that affect smoke yields of RYO cigarettes such as the incorporation of a filter to reduce yields. However, such studies must be complemented by surveys of cigarettes made by actual current RYO smokers. In one such investigation, it was found that the mean tar yields from cigarettes produced by 57% of the smokers were above the current maximum of 15 mg per cigarette for manufactured cigarettes. Currently 8% of manufactured cigarettes in the UK have a declared nicotine yield of greater than 1.1 mg per cigarette whereas 77% of RYO smokers produced cigarettes with a nicotine yield greater than this value.


Keywords: roll-your-own cigarettes; smoke yield; carbon monoxide; tar; nicotine     

Smokers are unaware of the filter vents now on most cigarettes: results of a national survey

OBJECTIVE: To evaluate awareness and knowledge of cigarette filter ventilation in a national probability sample of smokers of Ultra-light, Light, and regular cigarettes. DESIGN: Random-digit-dialling and computer-assisted telephone interviewing was used on a probability sample of daily cigarette smokers (ages 18 and above). SUBJECTS AND SETTING: 218 Smokers of Ultra-light cigarettes, 360 smokers of Light cigarettes, and 210 smokers of Regular cigarettes living in the continental United States. MAIN OUTCOME MEASURES: Percentage of respondents indicating knowledge of the presence of filter vents and the consequences of behavioural blocking of vents. RESULTS: Many smokers had not heard about or seen the filter holes: 43% (95% CI = 36 to 50%) of smokers of Ultra-lights, 39% (95% CI = 34 to 44%) of smokers of Lights, and 47% (95% CI = 40 to 54%) of smokers of Regulars. About two in three smokers either did not know of the existence of rings of small holes on the filters of some cigarettes, or did not know that blocking increases tar yields: 69% (95% CI = 63 to 75%) of Ultra- lights, 66% (95% CI = 61 to 71%) of Lights, and 69% (95% CI = 63 to 75%) of Regulars. CONCLUSIONS: Smokers are generally unaware of the presence and function of filter vents-a major design feature subject to behavioural blocking by smokers and now present on most cigarettes in the United States. Smokers and policy-makers need to be informed about the presence of filter vents and how vent blocking increases tar and nicotine yields from ostensibly very low-yield cigarettes.


     

Do increases in cigarette prices lead to increases in sales of cigarettes with high tar and nicotine yields?

We used scanner data on cigarette prices and sales collected from supermarkets across the United States from 1994 to 2004 to test the hypothesis that cigarette prices are positively correlated with sales of cigarettes with higher tar and nicotine content. During this period the average inflation-adjusted price for menthol cigarettes increased 55.8%. Price elasticities from multivariate regression models suggest that this price increase led to an increase of 1.73% in sales-weighted average tar yields and a 1.28% increase in sales-weighted average nicotine yields for menthol cigarettes. The 50.5% price increase of nonmenthol varieties over the same period yielded an estimated increase of 1% in tar per cigarette but no statistically significant increase in nicotine yields. An ordered probit model of the impact of cigarette prices on cigarette strength (ultra-light, light, full flavor, unfiltered) offers an explanation: As cigarette prices increase, the probability that stronger cigarette types will be sold increases. This effect is larger for menthol than for nonmenthol cigarettes. Our results are consistent with earlier population-based cross-sectional and longitudinal studies showing that higher cigarette prices and taxes are associated with increasing consumption of higher-yield cigarettes by smokers.     

Comparison of the nicotine content of tobacco used in bidis and conventional cigarettes

OBJECTIVE: To compare the nicotine content of 12 unfiltered brands of bidi cigarettes (hand rolled cigarettes imported from India) with 8 popular brands of filtered and unfiltered US and conventional cigarettes from India. MAIN OUTCOME MEASURES: Identical laboratory procedures were used to determine nicotine content (in duplicate) and physical characteristics. RESULTS: The nicotine concentration in the tobacco of bidi cigarettes (21.2 mg/g) was significantly greater than the tobacco from the commercial filtered (16.3 mg/g) and unfiltered cigarettes (13.5 mg/g). CONCLUSIONS: Bidi cigarettes contain higher concentrations of nicotine than conventional cigarettes. Therefore, it is logical to presume that bidi smokers are at risk of becoming nicotine dependent. These findings belief a popular belief among US teens that bidis are a safe alternative to commercial cigarettes.     

Dependence of tar, nicotine and carbon monoxide yields on physical parameters: implications for exposure, emissions control and monitoring

Objective

To estimate the extent to which tar, nicotine and carbon monoxide (TNCO) yields are dependent on cigarette design features such as burn rate, filter ventilation and paper porosity, and to consider the implications for human exposure and the regulation of TNCO emissions. A related aim is to determine whether accurate prediction of TNCO yields is possible using only simple physical parameters.

Design and methods

Datasets that include quantitative design parameters as well as measurements of TNCO yields collected under standard conditions with vents unblocked (International Organization for Standardization) and under intense conditions with vents fully blocked (Health Canada) were compiled from the literature (primarily US and UK brands). Forward stepwise multiple regression analysis is used to assess the relative importance of each design feature in explaining variability in the observed emissions. Using randomly split data subsets, multiple linear regression is used to model the dependence of TNCO yields on design features in the training subset and validated against the test subset. Tar and carbon monoxide correlate with many of the particulate‐ and volatile‐phase toxins in smoke, and brand values normalised to nicotine yield are used as surrogate measures of exposure within the bounds defined by non‐intense and intense smoking protocols.

Results and conclusions

Filter ventilation is the dominant control on measured TNCO emissions, but other factors including burn rate, amount of tobacco and paper porosity also contribute. Yields are predictable with reasonable accuracy and precision using only measured physical parameters. Surrogate exposure indicators suggest that filter ventilation does not lead to any reduction in exposure and that highly ventilated (low‐yield) brands may actually increase exposure to the more volatile toxins.Major reductions in tar, nicotine and carbon monoxide (TNCO) emissions as measured by smoking machines have been achieved by modifying cigarette design, thus enabling manufacturers to comply with regulations,¹ although the strategy of setting limits on emissions and publishing TNCO yields obtained under the International Organization for Standardization (ISO) smoking conditions is seriously questioned among public health practitioners.² All aspects of cigarette design, including filter, paper wrap, tobacco filler and additives, can be modified to influence machine‐measured yields to varying degrees,³ but little information is available on how each feature contributes to overall yield reduction, at least outside the tobacco industry.One design feature, namely filter ventilation (V^f), has been singled out for particular criticism on health grounds, because it reduces apparent emissions, yet can be overcome wittingly or unwittingly by blocking the vents with the fingers or lips,¹ and the smoker typically engages in other forms of compensatory behaviour to replace the deficiency in nicotine delivery. The literature largely assumes that filter ventilation is the only (or at least dominant) design feature that has been used by the tobacco industry to reduce yields.⁴ It is important to test this assumption in order to justify future research on the nature and extent of counteractive and compensatory behaviour. If other, less‐easily defeated design features make significant contributions to reducing yields, then by the same token their potential for reducing exposure to smoke emissions should not be overlooked. There is presently a dearth of useful quantitative information to inform policy on the relevance of these factors to emissions control and disclosure. The purposes of this paper are to (1) assess the relative contributions of filter ventilation and other design features to overall reductions in machine‐measured TNCO yields, (2) consider whether reduction in yields translates to reduction in exposure to toxins and (3) test whether the relationship between physical parameters and TNCO emissions can be used to generate adequate models for predicting the latter from the former. This may have relevance for the monitoring and surveillance of products in the absence of a laboratory with the capacity for chemical testing of emissions.Filter ventilation involves inserting small holes in the filter tip of a cigarette that act as vents allowing the introduction of external air during puffing so that a lower proportion of the puff volume is drawn at the burning coal.³ The effect is to reduce all emissions due to burning tobacco, although the effect is greatest on carbon monoxide (CO).^3,5,6 While filter ventilation is effective in reducing machine‐measured yields, the publication of such data can be misleading, as, no allowance is made for vent blocking or other modified behaviour by smokers in their quest for a desired level of nicotine delivery.^7,8 Because smokers of “low‐yield” cigarettes might gain a false sense of reduced harm,^2,9 there has been a vigorous debate with tobacco industry scientists on the evidence for vent blocking and the degree to which it applies in real‐world smoking.^10,11 Perhaps more relevant is strong evidence for the use of a range of strategies by smokers to compensate for the lower nicotine yield.² What is not clear is how ventilation and compensation act to modify exposure. Raw‐yield data are uninformative, but if these inter‐relationships were better understood, ventilation and all other design features could be assessed objectively in the context of reducing the smoker''s exposure to toxins.Cigarette design is constrained by the need to maximise the commercial potential of a brand while complying with legal limits on yields where these exist. Smoke is an aerosol of more than 4000 distinct components distributed among particulates and the gas phase. “Tar” is the collective term used for compounds in particulate form, CO is dominantly gaseous, whereas nicotine is partitioned between particulates and the gas phase.¹² These components are generated through the processes of distillation and pyrolysis (thermal decomposition) of tobacco and the oxidation of char during the heating of tobacco. Controlling the process to generate only those components sought by the smoker (such as nicotine, flavour, texture) is unrealistic; hence design strategies are used to maximise the delivery of these components at the mouth end of the cigarette while keeping the delivery of toxic components within specified limits.The undesirable components of smoke are widely understood by the public to be TNCO,⁹ yet there is consensus among the scientific community that most of the harmful effects are primarily attributable to specific components, typically volatile organic compounds, polycyclic aromatic hydrocarbons (PAHs), tobacco‐specific nitrosamines and the heavy metals.^13,14 Tar is a complex entity that contains several major carcinogens (including the PAHs), and the term is used in this study as the weight of particles trapped on a filter after a machine smoking test, less its nicotine and water content (nicotine‐free dry particulate matter, NFDPM). The concentrations of the toxins in tar may vary because of several factors; some are derived from the leaf but most are generated by the combustion process, which in turn is strongly influenced by cigarette design and smoking behaviour. Nicotine is not regarded as highly toxic, whereas CO is implicated in cardiovascular disease.The usefulness of these measured parameters is not in their toxicities but rather in the ways in which they can efficiently reflect other aspects of emission. Nicotine concentration will largely determine the way in which a cigarette is smoked in order to satisfy the smoker''s addiction. Measured tar correlates linearly with many important toxins that tend to partition into the particulate phase, including the important PAHs. This has been observed in many studies and is also the case in the datasets used in this study. CO correlates usefully with those toxins that partition into the vapour phase, again borne out by linear correlations in these datasets. Many of those toxins that partition between particulate and vapour phases can also be modelled by multiple regression. Overall, most of the major tobacco smoke toxins in the “Hoffmann list”,¹⁵ with the exception of the nitrosamines and some other nitrogenous compounds, correlate significantly with measured tar, CO or both.Over the latter half of the 20th century, the sales‐weighted average tar yield of US cigarettes reduced to about half that of the 1950s.¹⁶ The more important design features responsible for this reduction include new tobacco blends (although blending is more about generating flavours than the control of emissions³), the cut of tobacco in terms of strands per inch, the weight of tobacco used and dimensions of the cigarette, and use of reconstituted tobaccos (particularly expanded tobaccos, some of which contain additives to control combustion). High porosity and permeability of wrap paper facilitate ventilation with external air. This reduces the proportion of a puff derived from the burning coal, thus reducing all yields. In addition, vapour‐phase components such as CO may diffuse outwards, further reducing their yields. Additives are used in paper manufacturing to increase burn rates, thus reducing measured yields.¹⁷ Filters, typically of cellulose acetate, extract particulate phases from the aerosol and reduce tar and nicotine with various degrees of efficiency, although they have little effect on volatile emissions such as CO. Filter ventilation reduces the draw on the burning coal, thus reducing the emissions and diluting the smoke with external air. This is probably the most effective single design feature for reducing machine‐measured TNCO emissions, although the effects on the vapour and particulate phases differ and hence reductions in TNCO yields are not necessarily uniform.The approach taken in this study is to isolate the effect of filter ventilation from other design features by statistically comparing emissions data for cigarettes smoked with filter vents unblocked with data for the same cigarettes smoked with vents fully blocked. A similar approach was used in assessing the contributions of tobacco nicotine and filter ventilation to machine‐measured yields in the US, Canada and the UK,¹⁸ although the present study differs in focusing only on the physical controls. Studies of modern cigarettes from different geographical regions have highlighted the very strong negative correlation between yields of tar and other emissions with degree of filter ventilation.^4,19 Vent blocking would be expected to destroy this correlation unless other design features act in concert with filter ventilation to reduce yields.The relationship between machine‐measured yield and human exposure to smoke toxins is not simple and yield data can be a highly misleading guide to exposure.²⁰ Machines cannot replicate human smoking and there is very good evidence that smokers of highly ventilated cigarettes engage in other behaviours in order to satisfy their need for a given delivery of nicotine, such as puffing more frequently, taking deeper puffs (facilitated by ventilation), smoking more cigarettes, etc,^8,21 thus exposing themselves to the higher levels of emissions associated with unventilated brands. Furthermore, the lighter taste of ventilated brands encourages a false sense of security and reduces the motivation to quit.² These are important factors to consider when interpreting machine‐measured yields in terms of exposure to tobacco smoke toxins.     

Effect of the New York State cigarette fire safety standard on ignition propensity, smoke constituents, and the consumer market

Objectives: This study examines empirical evidence from the New York experience testing tobacco industry arguments made in opposition to fire safety standards for cigarettes. Design: Percentages of cigarettes exhibiting full length burns (FLBs), cigarette sales before and following the implementation of the New York standards, a sample of retail cigarette prices, brand availability, and selected smoke constituent yields were compared between cigarettes sold in New York and two other states. Cigarette paper analysis was conducted on cigarettes sold in New York. Results: New York cigarette brands averaged 10.0% FLBs as compared to 99.8% for California and Massachusetts brands. Reduced ignition propensity (RIP) appears to have been achieved by cigarette paper banding. Cigarette sales, prices, and brand availability do not appear to have been affected by the New York standards. Yields of the majority of smoke constituents tested did not differ substantially between RIP cigarettes sold in New York as compared to the same brands sold in Massachusetts. Average yields of tar, carbon monoxide, and two compounds were slightly higher, the yields of seven compounds were higher for one brand only, and nicotine was lower, among New York brands tested. Conclusions: RIP cigarette brands have been designed to meet the New York fire safety standards. Their introduction has not affected cigarette sales or prices in New York. There is no evidence that the small increases in smoke constituent yields affect the already highly toxic nature of cigarette smoke. Data on smoking caused fires, deaths, and injuries dating from after the change in law are not yet available. Such data will be able to address the question of whether the demonstrated reduced ignition standards are associated with reduced fires and injuries. Based on the New York experience, prior industry objections to producing RIP cigarettes are unfounded. Other states and nations should adopt similar standards.     

不同抽吸模式卷烟主流烟气中常规成分和某些有害成分释放研究

对比研究了ISO抽吸模式和加拿大深度抽吸模式下不同卷烟主流烟气中焦油、烟碱和水分3种常规成分释放量及一氧化碳、氨和苯酚3种有害成分释放量。结果表明, 加拿大深度抽吸模式下, 卷烟主流烟气中焦油、烟碱和水分3种常规成分及一氧化碳、氨和苯酚3种有害成分释放量远远高于ISO抽吸模式下的释放量;随着滤嘴通风率的增加, 主流烟气常规成分和某些有害成分释放量的增加幅度越来越大;主流烟气中水分释放量的增加幅度远远大于焦油、烟碱、一氧化碳、氨和苯酚释放量的增加幅度。     

Urinary tobacco-specific nitrosamines and 4-aminobiphenyl hemoglobin adducts measured in smokers of either regular or light cigarettes.

Cigarette brands may differ in their reported yields of "tar" as determined by the Federal Trade Commission smoking-machine method. Brands with relatively lower tar and nicotine yields often are described as light cigarettes. Smokers of light cigarettes generally maintain a nicotine intake comparable to that of smokers of regular cigarettes through compensatory smoking behaviors, but similar data have not been reported for carcinogen biomarkers. In the present study we measured serum cotinine concentrations (a marker of nicotine exposure), urinary levels of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL, a tobacco-specific nitrosamine [TSNA]), and hemoglobin adducts of 4-aminobiphenyl (4-ABP) in 150 smokers of either regular or light cigarettes. The TSNA and aromatic amines are known carcinogens in tobacco smoke. Multiple regression models were developed for each of the analytes and used to calculate adjusted geometric means. We found no significant differences in the levels of these biomarkers between customary users of light and regular cigarettes. Thus the concentrations of the carcinogen biomarkers NNAL and 4-ABP in the smokers who regularly smoked light cigarettes were essentially the same as those in the smokers who chose regular cigarettes.     

中美部分品牌烟草制品TSNA及其前体物的含量和关系

[目的]初步了解中美市售部分烟草制品TSNA及其前体物的含量及关系,为雪茄安全性研究提供参考.[方法]收集了中美市售卷烟及雪茄共37款烟草制品,对其TSNA以及其前体物含量进行测定,并进行相关分析.[结果](1)烟碱转化率美国雪茄最高,平均5.50％,中式卷烟样本烟碱转化率最低,平均为2.83％,且与美国雪茄样本存在显...     

爆珠滤棒设计参数对卷烟通风率及主流烟气成分的影响

为进一步拓宽爆珠滤棒设计思路,制备了不同爆珠直径和位置的爆珠滤棒和卷烟样品,分析了爆珠滤棒设计参数对常规卷烟主要物理指标、主流烟气常规指标及烟碱过滤效率的影响。结果表明:①随爆珠直径的增加,烟支滤嘴通风率和吸阻的升高幅度分别可达28.4%和28.1%;卷烟焦油和烟碱释放量分别降低6.8%和3.3%,烟碱过滤效率升高幅度达15.8%。②随爆珠距唇端距离的增加,滤嘴通风率和过滤效率在爆珠位置与打孔位置较近时达到最小。③爆珠破碎后,烟支吸阻显著降低,幅度可达210 Pa;焦油和烟碱释放量最大分别可升高1.9和0.08 mg/支,烟碱过滤效率降低16.3%。④随爆珠直径的增加,爆珠破碎后,烟支滤嘴通风率和总通风率整体降低,烟支吸阻呈增加趋势;烟碱和焦油释放量逐渐增加。⑤随爆珠距唇端距离的增加,爆珠破碎后,焦油和烟碱的释放量逐渐增加,过滤效率逐渐减小,并在爆珠距离打孔位置较近时出现极值。      

基于材料参数的中支烟烟气常规成分释放量预测模型

为建立基于材料参数的中支烟烟气常规成分释放量预测模型,采用中心组合结合正交试验设计方法设计了不同材料参数样品,使用线性回归和逐步回归方法构建了中支烟烟气总粒相物、焦油、烟碱、CO和水分释放量以及烟支开式吸阻和总通风率等7个预测模型,根据统计学原理中交叉验证标准差（RMSECV）最小及预测值与实测值线性相关系数最大的原则筛选出最优预测模型。采用市售中支烟对各预测模型进行了验证。结果表明:7个模型的预测精度良好,总粒相物、焦油、烟碱、CO、水分释放量以及烟支开式吸阻和总通风率平均预测相对偏差分别为4.0%、2.1%、6.0%、4.5%、8.3%、6.6%和3.2%,且对于不同配方、辅材参数的中支烟具有较好的适用性。      

烟支规格对卷烟物理、烟气、燃吸特性及感官质量的影响

为探究烟支规格对卷烟质量的影响,在烟丝原料、填充密度、卷烟纸透气度、接装纸规格、丝束材料以及滤棒吸阻条件相同的情况下卷制4种规格卷烟[烟支规格(烟支圆周×长度):常规(24.3 mm×84 mm)、22 mm卷烟(22 mm×84 mm)、中支(20 mm×89 mm)、细支(16.9 mm×97 mm)],检测其物理...     

不同滤嘴稀释度对卷烟主流烟气中重要香味成分输送量的影响

本文对滤嘴稀释度(通风度)分别为0(不打孔)、10%、30%、50%、70%的卷烟烟气中20种香味成分和总粒相物、烟碱、CO等常规成分进行了分析研究。香味物质试验采用标样加入法进行。总粒相物的二氯甲烷浸提液经同时蒸馏萃取并用碱液和饱和氯化钠溶液处理后,把抽提液浓缩,用毛细管气相色谱法和气相色谱/质谱法做了定性与定量分析,并按国标测定了总粒相物、烟碱、CO等组分输送量的变化。结果表明:这20种香味成分的输送量都是随着稀释度的增加而减少的,烟气中常规成分也都是随着稀释度的增加而减少的。但各种物质减少的程度不同,常规成分中CO和焦油减少较多,烟碱减少较少;香味成分中分子量较小、沸点较低的物质减少较多,而分子量较大、沸点较高的物质减少较少。随着稀释度的增加,卷烟烟气组分不仅量减少了,而且质也有所变化;不仅烟味减弱,而且香气质也发生一定的变化。这是应用通风稀释技术制造低焦油卷烟时进行叶组配方与加香加料所必须考虑的。      

辅助材料设计参数对烤烟型卷烟烟气焦油、烟碱和CO释放量的影响

为探索辅助材料与卷烟烟气化学成分之间的关系,研究了卷烟纸定量、卷烟纸透气度、成形纸透气度、接装纸透气度和滤棒吸阻对卷烟主流烟气焦油、烟碱和CO释放量的影响,并通过辅材设计参数的组合设计,建立了辅材设计参数预测焦油、烟碱和CO释放量的数学模型.结果表明:①卷烟纸定量增加CO释放量增加;②卷烟纸透气度增加,焦油、烟碱和CO释放量降低;③滤棒吸阻增加,焦油和烟碱释放量降低;④接装纸透气度增加,焦油、烟碱和CO释放量显著降低;⑤成形纸透气度增加,焦油、烟碱和CO释放量降低,降低程度与配合使用的接装纸透气度有关;⑥焦油、烟碱和CO释放量预测模型的预测值与实测值基本吻合.     

烟叶类型和外加成分对卷烟烟气粒相物pH值的影响

捕集在剑桥滤片上的卷烟主流烟气粒相物用去CO2 的蒸馏水提取 ,用精密 pH值计测量水提取液的 pH值。对于不同的单料烟卷烟 (包括烤烟、白肋烟、香料烟 )和不同类型的卷烟 (包括中式烤烟型、英式烤烟型、美式混合型 )的烟气pH值进行了测定 ,结果分别呈下列顺序 :白肋烟 >香料烟 >烤烟 ,混合型 >英式烤烟型 >中式烤烟型。分别将各种糖类、有机酸类、无机酸类、氨基酸类、生物碱类、盐类、酚类成分加入对照卷烟 ,探讨了这些化学成分对烟气 pH值的影响规律 ,结果表明 ,乳酸、蔗糖等可显著降低烟气pH值 ,烟碱可显著增加烟气pH值。提供了国内外一些卷烟牌号的烟气pH值测定数据。     

Extinguishing the rewarding value of smoke cues: pharmacological and behavioral treatments.

The present study examined several pharmacological and behavioral treatments designed to promote extinction of the responses to rewarding cigarette smoke cues. Pharmacological treatments comprised nicotine skin patches (21 mg/24 hr) and the nicotinic acetylcholine receptor antagonist mecamylamine (10 mg/day), administered separately or in combination. Behavioral manipulations included switching to denicotinized cigarettes, to cigarettes having different menthol flavor, or to ventilated-filter (low tar and nicotine) cigarettes. Smokers were assigned to the various treatments for 2 weeks before they quit smoking. During weekly test sessions, subjects rated the rewarding effects of their usual brands of cigarettes or cigarettes with different menthol content (mentholated vs. nonmentholated). Over the 2-week treatment period, all pharmacological treatments reduced ratings of reward for the usual-brand test cigarettes. Switching to smoking denicotinized cigarettes for 2 weeks similarly decreased rewarding effects of the usual-brand test cigarettes. Subjects also strongly preferred cigarettes with the same menthol content to which they were accustomed. However, manipulating the menthol content of the cigarettes smoked during the 2 weeks of treatment had different effects, depending on whether smokers habitually smoked mentholated or nonmentholated cigarettes. For menthol smokers, removal of the menthol cue hampered extinction of reward ratings for the usual-brand (mentholated) test cigarette. For nonmenthol smokers, addition of the menthol cue did not affect the progress of extinction of nonmenthol smoke cues. These findings demonstrate the importance of sensory cues in determining subjective reward and show that the reward value of these cues can be altered by removal of nicotine from tobacco or by pharmacological manipulations that interfere with the reinforcing effects of nicotine.     

Cost-effectiveness of a targeted disinfection program in household kitchens to prevent foodborne illnesses in the United States, Canada, and the United Kingdom

Foodborne illnesses impose a substantial economic and quality-of-life burden on society by way of acute morbidity and chronic sequelae. We developed an economic model to evaluate the potential cost-effectiveness of a disinfection program that targets high-risk food preparation activities in household kitchens. For the United States, Canada, and the United Kingdom, we used published literature and expert opinion to estimate the cost of the program (excluding the educational component); the number of cases of Salmonella, Campylobacter, and Escherichia coli O157:H7 infections prevented; and the economic and quality-of-life outcomes. In our primary analysis, the model estimated that approximately 80,000 infections could be prevented annually in U.S. households, resulting in 138 million dollars in direct medical cost savings (e.g., physician office visits and hospitalizations avoided), 15,845 quality-adjusted life-years (QALYs) gained, 788 million dollars in program costs, and a favorable cost-effectiveness ratio of 41,021 dollars/QALY gained. Results were similar for households in Canada and the United Kingdom (21,950 dollars Can/QALY gained and 86,341 pounds sterling/QALY gained, respectively). When we evaluated implementing the program only in U.S. households with high-risk members (those less than 5 years of age, greater than 65 years of age, or immunocompromised), the cost-effectiveness ratio was more favorable (10,163 dollars/QALY gained). Results were similar for high-risk households in Canada and the United Kingdom (1,915 dollars Can/QALY gained and 28,158 pounds sterling/QALY gained, respectively). Implementing a targeted disinfection program in household kitchens in the United States, Canada, and the United Kingdom appears to be a cost-effective strategy, falling within the range generally considered to warrant adoption and diffusion (<100,000 dollars/QALY gained).