Would a medium-nicotine, low-tar cigarette be less hazardous to health?

Smoking behaviour and exposure to carbon monoxide, nicotine, and tar were studied in 19 middle-tar smokers. All smoked their own brands for three weeks and then switched to either a conventional low-nicotine, low-tar brand (control) or a medium-nicotine, low-tar cigarette for a further three weeks, the order then being reversed. The medium-nicotine, low-tar brand also had a low delivery of carbon monoxide. With the medium-nicotine, low-tar cigarette mouth-level delivery and intake of nicotine was similar to that with the smokers' usual brands, and significantly greater than with the control low-tar cigarette. Intake of carbon monoxide from the medium-nicotine, low-tar cigarette was significantly less than with either own or control brands. With both low-tar brands mouth-level exposure to tar was reduced relative to smokers' usual cigarettes. There was no evidence, however, that the reduction in tar exposure was greater with the medium-nicotine brand than with the control low-tar cigarette. Both low tar brands were "'oversmoked" relative to subjects' usual middle-tar cigarettes. The medium-nicotine, low-tar cigarette was marginally more acceptable than the control brand, and the particular design used in the study resulted in a lower intake of carbon monoxide. In terms of reducing mouth-level exposure to tar, however, the medium-nicotine, low-tar cigarette had no advantage over the control low-tar product. In part this was because of the ratio of tar to nicotine delivery obtained by human smokers was not the same as that obtained by smoking machine.     

Trends in tar, nicotine, and carbon monoxide yields of UK cigarettes manufactured since 1934

The tar, nicotine, and carbon monoxide yields of cigarettes manufactured in the United Kingdom between 1934 and 1979 were studied. Over this period the average tar yield decreased by 49%, the nicotine yield by 31%, the carbon monoxide yield by 11%, all estimated on a sales-weighted basis. The average tar yield decreased progressively after the second world war, owing both to the introduction of filter cigarettes and to changes in the manufacture of plain cigarettes. The average nicotine yield increased initially, decreased by 43% from about 1950 to 1974, but increased again by 9% between 1974 and 1979. The average carbon monoxide yield started to decrease after about 1961; while it decreased substantially in plain cigarettes, the rapid increase in sales of filter cigarettes at this time, at the expense of plain cigarettes, largely offset the reduction in carbon monoxide yield that would otherwise have occurred. As with nicotine, carbon monoxide yield showed a small rise in later years (4% between 1976 and 1979). The trends in tar yield may well explain the reduction in lung cancer in the UK better than has been suspected hitherto. The trends in nicotine and carbon monoxide yields are probably not sufficiently different to distinguish which of them might be the more likely cause of cardiovascular disease.     

Carbon monoxide yield of cigarettes and its relation to cardiorespiratory disease

Estimates of the carbon monoxide yield of their cigarettes have been obtained for 4910 smokers (68% of all smokers) in the Whitehall study of men aged 40 to 64. In the 10 years after examination 635 men died. When men smoking cigarettes with high carbon monoxide yield were compared with those smoking cigarettes with a low yield, and after adjusting for age, employment grade, amount smoked, and tar yield, the risk of death was 32% lower for coronary heart disease, 49% higher for lung cancer, and 10% lower for total mortality; these differences were not statistically significant. Among men who said that they inhaled the risk of fatal coronary heart disease was 51% lower in the high carbon monoxide group (p less than 0.01), while the risk of lung cancer was 75% higher. These results provide no evidence that a smoker can reduce his risk of death by smoking a brand with a low carbon monoxide yield; he might even increase it. The complex interactions between characteristics of the smoker, smoking behaviour, constituents of tobacco smoke, and health are again demonstrated.     

Should intake of carbon monoxide be used as a guide to intake of other smoke constituents?

The relation between blood carboxyhaemoglobin (COHb) and plasma nicotine concentrations was studied in a group of 12 smokers smoking cigarettes of three levels of standard delivery. While the intake of carbon monoxide from a single cigarette was unrelated to the intake of nicotine, presmoking "trough" concentrations of the two substances (reflecting longer-term exposure) were highly correlated. Various other measures of nicotine exposure were at best only moderately correlated with blood nicotine concentrations. Thus trough COHb concentrations might be used to provide a reliable indication of the exposure to nicotine of individual smokers smoking the same type of cigarette, and of the relative exposure to nicotine of populations smoking cigarettes of different standard deliveries.     

Australian patterns of tobacco smoking in 1989

OBJECTIVE: To estimate the national prevalence of smoking. DESIGN: A total of 4820 adults aged 16 years and over (2364 men, 2456 women) were surveyed throughout Australia in 1989 by a large market research company. SETTING: Interviews were conducted in the participants' homes. RESULTS: Overall, 30.2% of men and 27.0% of women were current smokers; 29.8% of men and 19.3% of women were past smokers. The mean daily consumption of factory-made cigarettes among male smokers was 22 and among female smokers 18.9. Taking into account the published tar content of the brand smoked, it was estimated that the average daily exposure to tobacco tar for men was 204 mg and for women 157 mg. Occupational and educational status were inversely related to the prevalence of smoking. The most popular packet size was 25 (preferred by 48% of smokers) and those in lower occupational and educational categories were more likely to purchase cigarettes in large packet sizes. CONCLUSIONS: Comparison with an earlier series of studies commenced in 1974 showed that the national prevalence of smoking among adults has continued to fall, particularly among men.     

Increased risk of respiratory symptoms in young smokers of low tar cigarettes

The effect of cigarettes yielding less than 10 mg tar was investigated in a representative sample (n = 4729) of 16 and 18 year old Finns. The rate of response was 80%. Cough and phlegm were significantly increased in young people smoking low tar cigarettes. When more than nine cigarettes were smoked daily respiratory symptoms were 2.4-6.2 times more prevalent among those who smoked low tar cigarettes than among those who never smoked. No differences were found between the smokers of low tar and medium tar cigarettes (yielding tar 10-18 mg). These data disagree with the hypothesis that the new low tar brands of cigarettes are less likely to cause respiratory symptoms than the old medium tar brands.     

Smokers' understandings of cigarette yield labels

An important part of public health policy on the control of smoking is the promotion of a reduction in intake of tar by persons who continue to smoke. One method that may contribute towards such a reduction is to encourage smokers to choose cigarette brands that contain low tar levels. This in turn might be promoted by the comprehensible labelling of cigarette packets with tar yields. We tested our hypothesis that the current information about tar yield on cigarette packets is incomprehensible to smokers on a sample of 498 persons (original sample, 500) who smoked. Only 10 (2%) smokers were able to state the correct tar content of their cigarette. On a scaled range of tar levels in all cigarette brands that are available in Australia, 344 (69.1%) smokers underestimated the level in their cigarette brand. On this scale, 280 (56%) smokers placed randomly chosen tar levels in the wrong category. It was agreed by 360 (72%) smokers that comparative tar yields should be displayed at all points of tobacco sale. It is recommended that a condition of issuing a licence to retail tobacco should be that the tar, nicotine and carbon monoxide yield information for all cigarette brands that are available in a national market should be displayed prominently to the consumer by the retailer.     

Toward less hazardous cigarettes. Current advances.

Critical levels of selected cigarette smoke constituents have been expressed in terms of maximum numbers of pre-1960 cigarettes that a smoker may consume daily without increasing his mortality risk substantially above that of a nonsmoker. This could still imply an important risk, although it may be difficult to detect. We relate these levels to the yields of 27 current low tar and nicotine commercial cigarettes, as measured at the Oak Ridge National Laboratory. In addition, the yields of these selected constituents concomitant with the yield of 1 mg of nicotine are provided as a guide for the smoker who titrates or adjusts his smoking pattern to accommodate a fixed daily intake of nicotine.     

Breath analysis to detect recent exposure to carbon monoxide

Objectives: To determine the normal range for carbon monoxide concentrations in the exhaled breath of subjects in the emergency department and to develop a protocol for the use of a breath analyser to detect abnormal carbon monoxide exposure. Methods: A hand held breath analyser was used to measure end expiratory carbon monoxide concentrations in 382 consenting subjects. Questionnaire data were collected to assess the effect of common sources of carbon monoxide exposure on breath carbon monoxide levels. Smokers were used as a carbon monoxide exposed group for comparison with non-smokers. Results: The range of carbon monoxide concentrations obtained in the non-smoking group was 0–6 ppm and in the smoking group was 1–68 ppm. Smokers had a mean breath carbon monoxide concentration of 16.4 ppm and non-smokers had a mean of 1.26 ppm (95% confidence interval (CI) for difference 13.6 to 16.8 ppm). Male sex and frequent motor vehicle use were associated with slightly higher carbon monoxide concentrations (by 0.40, 95% CI 0.18 to 0.63 ppm, and 0.38, 95% CI 0.13 to 0.63 ppm, respectively) in the non-smoking group. Mean breath carbon monoxide concentrations increased in direct proportion to the number of cigarettes smoked (p<0.001) and there was a negative correlation between carbon monoxide and time since last smoking a cigarette (p<0.001). Altogether 23% of smokers had breath carbon monoxide concentrations in the range 1–6 ppm. Conclusions: Breath analysis was rapid and results correlated well with carbon monoxide exposure. In this population subjects with breath carbon monoxide concentrations greater than 6 ppm should be assessed for the risk of carbon monoxide poisoning. However even carbon monoxide concentrations less than 6 ppm do not exclude carbon monoxide poisoning within the last 24 hours.     

Passive exposure to tobacco smoke: saliva cotinine concentrations in a representative population sample of non-smoking schoolchildren

Saliva cotinine concentrations in 569 non-smoking schoolchildren were strongly related to the smoking habits of their parents. When neither parent smoked the mean concentration was 0.44 ng/ml, rising to 3.38 ng/ml when both parents were cigarette smokers. Mothers' smoking had a stronger influence than did fathers' (p less than 0.01). In addition, there was a small independent effect of number of siblings who smoked (p less than 0.01). The dose of nicotine received from fathers' smoking was estimated as equivalent to the active smoking of 30 cigarettes a year, that from mothers' smoking as equivalent to smoking 50 cigarettes a year, and that from both parents smoking as equivalent to smoking 80 cigarettes a year. This unsolicited burden may be prolonged throughout childhood and poses a definite risk to health.     

Pragmatic, observational study of bupropion treatment for smoking cessation in general practice

Background: Cigarette smoking remains the single largest cause of premature death in the United Kingdom. As part of the government''s national service framework for coronary heart disease, smoking cessation forms a key part of the strategy. Objectives: To determine the effectiveness of bupropion treatment for smoking cessation in a general practice setting, measuring continuous abstinence from smoking, from 8 weeks to 52 weeks. Design: Prospective observational study. Setting: One general practice (six whole time equivalent doctors, 11 070 patients) in rural Northumberland. Subjects: Of the 243 patients who presented to the practice over a one year period for smoking cessation, a total of 227 motivated people, who were appropriate for bupropion treatment as a pharmacological aid for smoking cessation, entered the study. Continuous smoking cessation at one year was validated by an exhaled carbon monoxide level of 10 ppm or less. Results: Fifty patients successfully gave up smoking, giving a one year smoking cessation prevalence with bupropion of 22% (95% confidence intervals (CI) 17% to 28%). There was no difference in success rate for sex, number of cigarettes smoked, the number of years smoking, or whether there were other smokers in the household or not. Conclusion: Bupropion treatment in this general practice helped 22% of motivated people to quit and remain stopped smoking at one year. Mainly nurses, whose prescribing rights are restricted and currently exclude bupropion, deliver smoking cessation services in primary care.     

某医院戒烟门诊患者特征及戒烟意愿分析

2009年1月至2011年12月,在复旦大学附属中山医院戒烟门诊就诊284例,男性273例（96．1％）,女性11例（3．9％）,平均49岁,平均每日吸烟量24支,平均吸烟时间26年,呼mc0体积分数平均倩为16×10-6．尼古丁依赖评分平均值5分。戒炯重要性得分8．5,信心得分6．7,准备好戒烟的得分为7．6。门诊患者1个月戒断率66．1％,3个月50．9％。说明戒烟门诊患者吸烟依赖程度偏高,吸炯时间较长,有戒烟认识,但信心不足。     

Health risks associated with cigar smoking

This article summarizes principal findings from a conference convened by the American Cancer Society in June 1998 to examine the health risks of cigar smoking. State-of-the-science reports were presented and 120 attendees (representing government and private agencies, academia, health educators, and tobacco control experts) participated in panels and summary development discussions. The following conclusions were reached by consensus: (1) rates of cigar smoking are rising among both adults and adolescents; (2) smoking cigars instead of cigarettes does not reduce the risk of nicotine addiction; (3) as the number of cigars smoked and the amount of smoke inhaled increases, the risk of death related to cigar smoking approaches that of cigarette smoking; (4) cigar smoke contains higher concentrations of toxic and carcinogenic compounds than cigarettes and is a major source of fine-particle and carbon monoxide indoor air pollution; and (5) cigar smoking is known to cause cancers of the lung and upper aerodigestive tract. JAMA. 2000;284:735-740     

Nasal nicotine solution: a potential aid to giving up smoking?

A nasal solution was developed containing 2 mg nicotine for use as a kind of liquid snuff. Its absorption was studied in three subjects. An average peak of plasma nicotine concentrations of 86.9 nmol/l (14.1 ng/ml) was reached seven and a half minutes after taking the solution. This compared with an average peak of 158.4 nmol/l (25.7 ng/ml) one and a half minutes after completing (but seven and a half minutes after starting) a middle tar cigarette (1.4 mg nicotine) and an average peak of 52.4 nmol/l (8.5 ng/ml) after chewing nicotine gum (2 mg nicotine) for 30 minutes. The more rapid and efficient absorption of nicotine from the nasal nicotine solution than from nicotine chewing gum suggests that it might prove a useful aid to giving up smoking. Nasal nicotine solution might be particularly useful in smokers for whom the gum is less suitable on account of dentures or peptic ulcers or who experience nausea and dyspeptic symptoms from the gum.     

卷烟主流烟气及其物理化学检测数据的挖掘与信息抽提

应用因子分析与典型相关分析方法对卷烟生产企业批量样品实际检测的18个检测指标进行了数据挖掘与信息抽提。因子分析表明:可用12个独立的公共因子来描述卷烟质量,其中主流烟气中的总粒相物、烟碱、焦油与物理指标稀释率、闭式吸阻相关性很强,且可用第一主因子来体现其对卷烟质量的影响;第二主因子主要体现了总氮的信息,前两个主因子占总信息量的66%。典型相关分析表明:卷烟主流烟气与物理化学信息间存在显著的整体相关,其中反映主流烟气信息的U典型变量主要来自总粒相物、焦油、烟碱、水分、水分含率及抽吸口数的贡献;反映物理、化学指标信息的V典型变量主要来自稀释率、闭式吸阻、单支重及总糖、氯等化学指标的贡献,其中稀释率的作用最大。而CO、圆周与硬度对卷烟主流烟气与理化性质两类信息间的整体相关性的影响不大。有关结果对卷烟的降焦减害、建立卷烟主流烟气信息与理化信息间定量关系提供了重要信息和理论依据。     

Smoker's face: an underrated clinical sign?

In a prospective survey of patients attending a general medical outpatient clinic roughly half the current cigarette smokers who had smoked for 10 years or more were identified, using defined criteria, by their facial features alone. These facial features, designated "smoker's face," were present in three (8%) of those who had smoked cigarettes for 10 years or more in the past and in none of the non-smokers. The association of smoker's face with current smoking that had continued for 10 years or more was significant (p less than 0.001) and remained after the patient's age, social class, exposure to sunlight, recent change of weight, and estimated lifetime consumption of cigarettes were controlled for. Smoker's face may be a helpful indicator in antismoking campaigns.     

Who profits from tobacco sales to children?

It is estimated that more than 3 million American children under 18 years of age consume 947 million packs of cigarettes and 26 million containers of smokeless tobacco yearly. These tobacco products account for annual sales of $1.26 billion. Approximately 3% of tobacco industry profits ($221 million in 1988) derive directly from the sale of cigarettes to children, an activity that is illegal in 43 states. Approximately half of the tobacco industry's profits, or $3.35 billion annually, derives from sales to people who became addicted to nicotine as children. Tax revenues to the federal ($152 million) and state ($173 million) governments from cigarette sales to children dwarf governmental expenditures on smoking and health. We describe how dozens of communities have effectively enforced laws that prohibit the distribution of tobacco to children and offer some suggestions for increasing efforts to prevent nicotine addiction.     

Research letter: Intentions of smokers to use free nicotine replacement therapy

Public health initiatives to distribute nicotine replacement therapy free of charge as a means of promoting smoking cessation are ongoing. Are there enough smokers interested in using nicotine replacement therapy to have a substantial impact on the prevalence of smoking if this aid were distributed free to all interested smokers? We conducted a telephone survey of 825 randomly selected daily smokers aged 18 years or older who had smoked at least 10 cigarettes per day at some point in their lives. Overall, 58.9% of the respondents said they would be interested in nicotine replacement therapy if it were offered for free. Of those interested, almost all (93.8%) said that they would use the nicotine replacement therapy to help them quit for good. There were differences in the levels of interest: smokers who intended to quit were more interested in using the nicotine replacement therapy than those who planned to reduce or maintain their smoking.     

Extreme but asymptomatic carboxyhemoglobinemia and chronic lung disease

Carboxyhemoglobinemia is a well-known consequence of carbon monoxide exposure from smoking. However, only moderately elevated levels have been reported. We report the case of an asymptomatic man with severe chronic obstructive lung disease and carboxyhemoglobin levels repeatedly in excess of 30% (maximum, 38.0%) due to smoking. The mechanism by which such high levels were attained was primrily a combination of arterial hypoxia and a high carbon monoxide yield from tobacco. For a given level of carbon monoxide exposure, the hypoxic person will attain a higher carboxyhemoglobin level than will a person without hypoxia.     

Australian patterns of tobacco smoking in 1986

A total of 9440 Australian men and women of over 15 years of age was interviewed at home in 1986 to determine the prevalence and consumption levels of tobacco products. Current smokers were defined as those who smoked any combination of cigarettes, cigars or pipes regularly. The percentage of current smokers among men was 32.9% and among women was 28.5%, and the peak prevalence of smoking was in the age-group 20-24 years for both men (40.5%) and women (40.8%). Among men, 27.7% were past smokers, and among women, 16.5% were past smokers. The proportion of past smokers among those who had ever smoked was higher in men (0.46) than among women (0.37), but in the younger age groups there was no relative excess among men. Male smokers consumed more cigarettes per day than did female smokers and men were exposed to a higher daily average amount of cigarette tar. Sociodemographic variables that were associated with smoking in both men and women included age and educational and occupational level. Asian-born persons had a significantly lower prevalence of smoking than did persons who were born in Australia.