Respiratory nicotine absorption in non-smoking females during passive smoking

Secondhand smoke increases the risk of developing kidney stone disease

Research indicates smoking increases the risk of various kidney diseases, although the risk of developing kidney stone disease in non-smokers exposed to secondhand smoke is unknown. This study analyzed a total of 19,430 never-smokers with no history of kidney stone disease who participated in the Taiwan Biobank from 2008 to 2019. They were divided into two groups by secondhand smoke exposure; no exposure and exposure groups; the mean age of participants was 51 years, and 81% were women. Incident kidney stone development was observed in 352 (2.0%) and 50 (3.3%) participants in the no exposure and exposure groups during a mean follow-up of 47 months. The odds ratio (OR) of incident kidney stone was significantly higher in the exposure group than the no exposure group [OR, 1.64; 95% confidence interval (95% CI) 1.21 to 2.23]. Participants with > 1.2 h per week exposure were associated with almost twofold risk of developing kidney stones compared with no exposure (OR, 1.92; 95% CI 1.29 to 2.86). Our study suggests that secondhand smoke is a risk factor for development of kidney stones and supports the need for a prospective evaluation of this finding.

Airborne Nicotine, Secondhand Smoke, and Precursors to Adolescent Smoking

BACKGROUND AND OBJECTIVES

Secondhand smoke (SHS) directly increases exposure to airborne nicotine, tobacco's main psychoactive substance. When exposed to SHS, nonsmokers inhale 60% to 80% of airborne nicotine, absorb concentrations similar to those absorbed by smokers, and display high levels of nicotine biomarkers. Social modeling, or observing other smokers, is a well-established predictor of smoking during adolescence. Observing smokers also leads to increased pharmacological exposure to airborne nicotine via SHS. The objective of this study is to investigate whether greater exposure to airborne nicotine via SHS increases the risk for smoking initiation precursors among never-smoking adolescents.

METHODS

Secondary students (N = 406; never-smokers: n = 338, 53% girls, mean age = 12.9, SD = 0.4) participated in the AdoQuest II longitudinal cohort. They answered questionnaires about social exposure to smoking (parents, siblings, peers) and known smoking precursors (eg, expected benefits and/or costs, SHS aversion, smoking susceptibility, and nicotine dependence symptoms). Saliva and hair samples were collected to derive biomarkers of cotinine and nicotine. Adolescents wore a passive monitor for 1 week to measure airborne nicotine.

RESULTS

Higher airborne nicotine was significantly associated with greater expected benefits (R² = 0.024) and lower expected costs (R² = 0.014). Higher social exposure was significantly associated with more temptation to try smoking (R² = 0.025), lower aversion to SHS (R² = 0.038), and greater smoking susceptibility (R² = 0.071). Greater social exposure was significantly associated with more nicotine dependence symptoms; this relation worsened with higher nicotine exposure (cotinine R² = 0.096; airborne nicotine R² = 0.088).

CONCLUSIONS

Airborne nicotine exposure via SHS is a plausible risk factor for smoking initiation during adolescence. Public health implications include limiting airborne nicotine through smoking bans in homes and cars, in addition to stringent restrictions for e-cigarettes.

Measurements of dermal uptake of nicotine directly from air and clothing

In this preliminary study, we have investigated whether dermal uptake of nicotine directly from air or indirectly from clothing can be a meaningful exposure pathway. Two participants wearing only shorts and a third participant wearing clean cotton clothes were exposed to environmental tobacco smoke (ETS), generated by mechanically "smoking" cigarettes, for three hours in a chamber while breathing clean air from head-enveloping hoods. The average nicotine concentration (420 μg/m³ ) was comparable to the highest levels reported for smoking sections of pubs. Urine samples were collected immediately before exposure and 60 hour post-exposure for bare-skinned participants. For the clothed participant, post-exposure urine samples were collected for 24 hour. This participant then entered the chamber for another three-hour exposure wearing a hood and clothes, including a shirt that had been exposed for five days to elevated nicotine levels. The urine samples were analyzed for nicotine and two metabolites-cotinine and 3OH-cotinine. Peak urinary cotinine and 3OH-cotinine concentrations for the bare-skinned participants were comparable to levels measured among non-smokers in hospitality environments before smoking bans. The amount of dermally absorbed nicotine for each bare-skinned participant was conservatively estimated at 570 μg, but may have been larger. For the participant wearing clean clothes, uptake was ~20 μg, and while wearing a shirt previously exposed to nicotine, uptake was ~80 μg. This study demonstrates meaningful dermal uptake of nicotine directly from air or from nicotine-exposed clothes. The findings are especially relevant for children in homes with smoking or vaping.

Quantification of ETS exposure in hospitality workers who have never smoked

BACKGROUND

Environmental Tobacco Smoke (ETS) was classified as human carcinogen (K1) by the German Research Council in 1998. According to epidemiological studies, the relative risk especially for lung cancer might be twice as high in persons who have never smoked but who are in the highest exposure category, for example hospitality workers. In order to implement these results in the German regulations on occupational illnesses, a valid method is needed to retrospectively assess the cumulative ETS exposure in the hospitality environment.

METHODS

A literature-based review was carried out to locate a method that can be used for the German hospitality sector. Studies assessing ETS exposure using biological markers (for example urinary cotinine, DNA adducts) or questionnaires were excluded. Biological markers are not considered relevant as they assess exposure only over the last hours, weeks or months. Self-reported exposure based on questionnaires also does not seem adequate for medico-legal purposes. Therefore, retrospective exposure assessment should be based on mathematical models to approximate past exposure.

RESULTS

For this purpose a validated model developed by Repace and Lowrey was considered appropriate. It offers the possibility of retrospectively assessing exposure with existing parameters (such as environmental dimensions, average number of smokers, ventilation characteristics and duration of exposure). The relative risk of lung cancer can then be estimated based on the individual cumulative exposure of the worker.

CONCLUSION

In conclusion, having adapted it to the German hospitality sector, an existing mathematical model appears to be capable of approximating the cumulative exposure. However, the level of uncertainty of these approximations has to be taken into account, especially for diseases with a long latency period such as lung cancer.

Hookah (Shisha, Narghile) Smoking and Environmental Tobacco Smoke (ETS). A critical review of the relevant literature and the public health consequences

Hookah (narghile, shisha, "water-pipe") smoking is now seen by public health officials as a global tobacco epidemic. Cigarette Environmental Tobacco Smoke (ETS) is classically understood as a combination of Side-Stream Smoke (SSS) and Exhaled Main-Stream Smoke (EMSS), both diluted and aged. Some of the corresponding cigarette studies have served as the scientific basis for stringent legislation on indoor smoking across the world. Interestingly, one of the distinctive traits of the hookah device is that it generates almost no SSS. Indeed, its ETS is made up almost exclusively by the smoke exhaled by the smoker (EMSS), i.e. which has been filtered by the hookah at the level of the bowl, inside the water, along the hose and then by the smoker's respiratory tract itself. The present paper reviews the sparse and scattered scientific evidence available about hookah EMSS and the corresponding inferences that can be drawn from the composition of cigarette EMSS. The reviewed literature shows that most of hookah ETS is made up of EMSS and that the latter qualitatively differs from MSS. Keeping in mind that the first victim of passive smoking is the active smoker her/himself, the toxicity of hookah ETS for non-smokers should not be overestimated and hyped in an unscientific way.

Nicotine dependence symptoms among young never-smokers exposed to secondhand tobacco smoke

BACKGROUND

To extend previous observations that secondhand tobacco smoke (SHS) is associated with nicotine markers in children, we investigated if SHS exposure is associated with self-reports of nicotine dependence (ND) symptoms among young never-smokers.

METHOD

Data on number of persons who smoke inside the home, number of days exposed to SHS in a motor vehicle in the past week, number of parents, siblings, and friends who smoke, and ND symptoms, were collected from 10-12 year-old students in self-report questionnaires. The association between SHS and ND symptoms among young never-smokers was assessed in logistic regression models.

RESULTS

Sixty-nine of 1488 never-smokers (5%) reported one or more ND symptom. After controlling for sibling and peer smoking, and susceptibility to initiating smoking, exposure to SHS in a motor vehicle was independently associated with ND symptoms (OR, 95% CI=1.2, 1.0-1.4). The OR for number of persons who smoke inside the home was 1.1 (0.9-1.4).

CONCLUSION

SHS exposure in motor vehicles may be associated with ND symptoms among young never-smokers. If replicated, this finding provides support for interventions that promote non-smoking in motor vehicles.

Secondhand smoke and nicotine exposure: a brief review

Secondhand tobacco smoke exposure is linked to a number of adverse health outcomes. This paper reviews published studies examining nicotine levels related to exposure to secondhand tobacco smoke. Twenty-two field studies measuring biological levels of nicotine associated with secondhand tobacco smoke exposure were evaluated. Positive associations between self-reported and/or objective measures of secondhand tobacco smoke exposure and concentrations of nicotine and/or biomarkers of nicotine in the body were frequently reported. Two studies indicated that nicotine exposure from secondhand tobacco smoke can engender plasma nicotine concentrations that are equivalent to levels produced by tobacco smoking and that are associated with nicotine-induced changes in behavior. Future research should examine whether nicotine exposure from secondhand tobacco smoke has functional effects on neurobiological and behavioral processes associated with tobacco use.

Behavioral effects of nicotine exposure from secondhand tobacco smoke among bar and restaurant workers

This study explores the behavioral effects of nicotine exposure from secondhand tobacco smoke (SHS) on bar and restaurant workers. Baseline data were obtained from a longitudinal study of 105 bar and restaurant workers. Hair nicotine, self-reported SHS exposure, smoking status, symptoms of nicotine exposure after being exposed to a smoky environment, and nicotine dependence were assessed. Nonsmokers reporting four or more symptoms of nicotine exposure had higher hair nicotine levels than those reporting less than four symptoms. Nonsmokers with higher hair nicotine levels were 2.2 times more likely to report 4 or more behavioral symptoms. Self-reported secondhand tobacco smoke exposure and hair nicotine were not predictive of nicotine dependence among smokers. Nicotine exposure from secondhand tobacco smoke may have important behavioral outcomes in nonsmokers. This study provides further evidence for the importance of prohibiting smoking in hospitality venues to protect the health of workers.

Significance of ammonium compounds on nicotine exposure to cigarette smokers

The tobacco industry publicly contends that ammonia compounds are solely used as tobacco additive for purposes of tobacco flavoring, process conditioning and reduction of its subjective harshness and irritation. However, neither objective scientific reports, nor the contents of a large number of internal tobacco company documents support this contention. The present review focuses on the hypothesis that addition of ammonium compounds to tobacco enhances global tobacco use due to smoke alkalization and enhanced free-nicotine nicotine exposure. Obviously, ammonia enhances the alkalinity of tobacco smoke. Consequently, the equilibrium shifts from non-volatile nicotine salts to the volatile free base that is more readily absorbed from the airways. The observed change in the kinetics of nicotine (i.e., shorter t(1/2) and higher c(max)) after ammoniation is, however, predominantly due to the higher concentration of nicotine in the smoke, rather than to an increase in the absorption rate of free-base nicotine in the respiratory tract. Although several findings support the hypothesis, additional studies are required and suggested to provide a proper, objective and independent scientific judgment about the effect of tobacco ammoniation on nicotine bioavailability. Scientific and public awareness of the effects of tobacco-specific ammonia compounds may stimulate global control, legislation and restriction of their use in cigarette manufacture.

The retention of tobacco smoke constituents in the human respiratory tract

Measurements on the retention of cigarette smoke constituents in the human respiratory tract have been undertake for more than 100 years. The first studies on nicotine retention were begun by Lehmann in Germany in 1903 and published in 1908. The first studies on the retention of smoke particulate matter were published by Baumbereger in the United States in 1923. Since those early publications, many studies have been undertaken, more or less continuously. This article is a review of the work that has been done over the last 100 years, including a large number of unpublished studies undertaken by British American Tobacco in Southampton, UK. The techniques used have evolved over the years and there is a certain amount of variation in the data. However, the general trends in the results are reassuringly consistent. The bulk of the studies indicate that, on average, 60 to 80% of the mainstream smoke particulate matter is retained in the lungs after inhalation. For nicotine, carbon monoxide, nitric oxide, and aldehydes the total retentions are of the order of 90-100, 55-65, 100, and approximately 90%, respectively, during cigarette smoke inhalation. For most smoke constituents the retentions in the mouth only are considerably smaller than in the whole respiratory tract. The lung retention values for smoke particulate matter are dependent on the depth of inhalation, hold time in the lungs, exhalation volume, and other factors. However, the degree of nicotine retention following inhalation is not markedly influenced by changes in respiratory parameters. Furthermore, the percentage retentions for smoke particulate matter and nicotine are smaller for nonsmoking subjects exposed to environmental tobacco smoke than with active smoking. The smoke retentions are related to properties of the smoke aerosol particles and gases and their behavior as they travel through the respiratory tract. This includes particle growth in the respiratory tract and evaporation of gases out of the particles, and relevant aspects of these processes are also reviewed.

Metabolism and Disposition Kinetics of Nicotine

Nicotine is of importance as the addictive chemical in tobacco, pharmacotherapy for smoking cessation, a potential medication for several diseases, and a useful probe drug for phenotyping cytochrome P450 2A6 (CYP2A6). We review current knowledge about the metabolism and disposition kinetics of nicotine, some other naturally occurring tobacco alkaloids, and nicotine analogs that are under development as potential therapeutic agents. The focus is on studies in humans, but animal data are mentioned when relevant to the interpretation of human data. The pathways of nicotine metabolism are described in detail. Absorption, distribution, metabolism, and excretion of nicotine and related compounds are reviewed. Enzymes involved in nicotine metabolism including cytochrome P450 enzymes, aldehyde oxidase, flavin-containing monooxygenase 3, amine N-methyltransferase, and UDP-glucuronosyltransferases are represented, as well as factors affecting metabolism, such as genetic variations in metabolic enzymes, effects of diet, age, gender, pregnancy, liver and kidney diseases, and racial and ethnic differences. Also effects of smoking and various inhibitors and inducers, including oral contraceptives, on nicotine metabolism are discussed. Due to the significance of the CYP2A6 enzyme in nicotine clearance, special emphasis is given to the effects and population distributions of CYP2A6 alleles and the regulation of CYP2A6 enzyme.

Relationship between environmental tobacco smoke and urinary cotinine levels in passive smokers at their residence

Studies of the health effects of environmental tobacco smoke (ETS) using measured air concentrations are subject to bias. Cotinine, a nicotine metabolite detected in urine, has been recommended as a quantitative measure of nicotine intake and thus as a marker for ETS exposure in humans. The aim of this study was to correlate home indoor ETS levels with passive smokers' urinary cotinine levels. The urinary cotinine concentrations of 57 non-smoking women who spend >19 h a day at home and the nicotine levels in their living room air were measured over a period of 24 h. Nicotine and urinary cotinine levels were analyzed using GC/MS and HPLC/UV, respectively. In addition, information was collected regarding the smoking habits of the subjects' families. A significant correlation was found between the nicotine levels in indoor air and the urinary cotinine to creatinine ratio of the passive smokers. The smoking habits of the subjects' family members were also correlated to the urinary cotinine levels of the passive smokers.

Determination of the nicotine content of various edible nightshades (Solanaceae) and their products and estimation of the associated dietary nicotine intake

This investigation was initiated as a result of proposals in the literature that dietary nicotine intake could contribute to the level of nicotine metabolites in biological fluids such as salivary cotinine concentration. Nicotine concentration was determined in several frequently consumed vegetables from the nightshade family (Solanaceae) (i.e., tomatoes, potatoes, aubergines, and peppers), as well as in some of their processed products. The edible Solanaceae fruit analyzed in this investigation were found to contain relatively consistent amounts of nicotine in the range of 2-7 microg/kg for fresh fruits. Nevertheless, the nicotine concentrations of the investigated tomato varieties decreased significantly with increasing degree of ripening of the fruits. In addition, a variety of black as well as green teas was investigated for the nicotine content. Nicotine content in tea leaves was found to be highly variable and sometimes much larger than in the Solanaceae fruits. On the basis of the observed concentrations and the respective food consumption data for different countries, a distributive analysis of the results suggests that the mean daily dietary nicotine intake for the population of the countries for which consumption data were available is approximately 1.4 microg/day, 2.25 microg/day at the 95th percentile.

Passive smoking and pregnancy outcome in central Poland

1. The present investigation was undertaken to evaluate the effect of environmental tobacco smoke (ETS) on the risk of preterm delivery (PD) and small-for-gestational age (SGA) infants in a female non-smoking population of central Poland. 2. The study group were 1751 women classified as non-smokers in the comprehensive project on 'Socio-economic and environmental risk factors of preterm delivery and small-for-gestationaI-age babies in central Poland' conducted on a randomly selected population of 2080 women who gave birth to a child between June 1, 1996 and May 31, 1997. The PD group comprised 95 non-smoking women who delivered before 37 weeks of pregnancy and the SGA group included 111 non-smoking mothers of babies with birthweight below the 10th percentile of the standard curves for central Poland. Passive exposure to tobacco smoke was determined based on a structured interview. 3. In the stepwise multiple logistic regression model maternal passive smoke exposure lasting 7 h or more was found to be a significant risk factor for preterm delivery. No significant effect of passive smoking on the risk of SGA was observed. 4. The information about the adverse effects of ETS exposure on pregnancy duration and outcome should be incorporated in the health promotion programmes for women.

Gender differences in the pharmacology of nicotine addiction

Smoking rates have declined in recent years less rapidly in women than in men. More adolescent girls than boys are currently smoking. Quitting smoking is reported in many studies to be more difficult in women than in men. These observations suggest that there may be gender differences in the nature of nicotine addiction. Gender differences in various pharmacological processes involved in nicotine addiction are reviewed. Women take in less nicotine from smoking per cigarette than men but, because of slower metabolism, nicotine levels in the body for a given number of cigarettes per day are similar in male and female smokers. Women tend to be less sensitive to the discriminative effects of nicotine and tend to regulate nicotine intake less precisely than men. On the other hand, women appear to be more sensitive to the effects of nicotine in reducing negative affect and reducing body weight. There is a strong association between depression and smoking, and this association appears to be stronger in women than in men. Women tend to respond more to environmental cues associated with smoking than do men. Thus, several lines of evidence suggest that nicotine addiction is different in women than in men. Understanding the basis for gender differences may be of utility in individualizing and optimizing smoking cessation therapy.

Air nicotine and saliva cotinine as indicators of workplace passive smoking exposure and risk

We model nicotine from environmental tobacco smoke (ETS) in office air and salivary cotinine in nonsmoking U.S. workers. We estimate that: an average salivary cotinine level of 0.4 ng/ml corresponds to an increased lifetime mortality risk of 1/1000 for lung cancer, and 1/100 for heart disease; > 95% of ETS-exposed office workers exceed OSHA's significant risk level for heart disease mortality, and 60% exceed significant risk for lung cancer mortality; 4000 heart disease deaths and 400 lung cancer deaths occur annually among office workers from passive smoking in the workplace, at the current 28% prevalence of unrestricted smoking in the office workplace.

Urinary cotinine in children and adults during and after semiexperimental exposure to environmental tobacco smoke

Urinary cotinine (U-cotinine) as a biomarker of environmental tobacco smoke exposure was evaluated in 14 children (age 4-11 y) and in 7 adults who were exposed to environmental tobacco smoke at an air nicotine level of 110 mg/m3 for 2 h in a bus. Nicotine in air and U-cotinine were measured by gas chromatography/mass spectrometry before, during, and after the experiment. U-cotinine rose rapidly to a maximum after a median of 6 h following the end of exposure; remained at an apparent plateau for half a day; and then decreased exponentially, with a mean half-time of 19 h (95% confidence interval 18-20 h; no significant difference between children and adults). The maximum U-cotinine was higher in the children (mean = 22 mg/l) than in the adults (13 mg/l; p = .005); decreased with age among the children (r = -.74; p = .002); and increased as the estimated inhaled nicotine dose increased. Therefore, the findings of the present study showed that young children had higher U-cotinine than adults at the same experimental environmental tobacco smoke exposure, probably because they had a higher relative nicotine dose because of a higher relative ventilation rate, and possibly also because of metabolic differences; the elimination rate did not differ. The long half-time makes U-cotinine a good biomarker of environmental tobacco smoke exposure; the time of sampling is not very critical. Dilution-adjusted concentrations should be employed, and in children, preferably by density correction. A certain urinary cotinine level indicates a lower environmental tobacco smoke exposure in a small child than in an adult.

Decline in the phagocytic function of alveolar macrophages from mice exposed to cigarette smoke

An investigation was made of the effects of a short and acute exposure to cigarette smoke on the capacity of alveolar macrophages from mice to carry out all stages of the phagocytic process. Cigarettes were commercial 80 mm filter cigarettes that contained 17 mg of tar and 1.1 mg of nicotine per cigarette. The acute exposure of each animal was with one cigarette for 15 min (until the complete consumption of the cigarette) in a box-shaped plastic chamber, 7732 cm3 vol and 450 cm2 floor surface, with a 3 cm dia airhole. Animals were sacrificed immediately after the exposure to the smoke. The results showed no differences either in the adherence or in the chemotaxis capacities between alveolar macrophages from control mice and from mice exposed to cigarette smoke. However, there was a significant decline both in attachment capacity and in ingestion capacity for Candida albicans. The reason for this was a decline in the number of macrophages with phagocytic capacity (percent of phagocytosis) and in the number of C. albicans phagocytized per cell (phagocytic efficiency). The conclusion is that a short, acute exposure to a smoke-filled atmosphere induced a decrease in the phagocytic function of alveolar macrophages.

An enforceable indoor air quality standard for environmental tobacco smoke in the workplace

Environmental tobacco smoke (ETS) has recently been determined by U.S. environmental and occupational health authorities to be a human carcinogen. We develop a model which permits using atmospheric nicotine measurements to estimate nonsmokers' ETS lung cancer risks in individual workplaces for the first time. We estimate that during the 1980s, the U.S. nonsmoking adult population's median nicotine lung exposure (homes and workplaces combined) was 143 micrograms (micrograms) of nicotine daily, and that most-exposed adult nonsmokers inhaled 1430 micrograms/day. These exposure estimates are validated by pharmacokinetic modeling which yields the corresponding steady-state dose of the nicotine metabolite, cotinine. For U.S. adult nonsmokers of working age, we estimate median cotinine values of about 1.0 nanogram per milliliter (ng/ml) in plasma, and 6.2 ng/ml in urine; for most-exposed nonsmokers, we estimate cotinine concentrations of about 10 ng/ml in plasma and 62 ng/ml in urine. These values are consistent to within 15% of the cotinine values observed in contemporaneous clinical epidemiological studies. Corresponding median risk from ETS exposure in U.S. nonsmokers during the 1980s is estimated at about two lung cancer deaths (LCDs) per 1000 at risk, and for most-exposed nonsmokers, about two LCDs per 100. Risks abroad appear similar. Modeling of the lung cancer mortality risk from passive smoking suggests that de minimis [i.e., "acceptable" (10(-6))], risk occurs at an 8-hr time-weighted-average exposure concentration of 7.5 nanograms of ETS nicotine per cubic meter of workplace air for a working lifetime of 40 years. This model is based upon a linear exposure-response relationship validated by physical, clinical, and epidemiological data. From available data, it appears that workplaces without effective smoking policies considerably exceed this de minimis risk standard. For a substantial fraction of the 59 million nonsmoking workers in the U.S., current workplace exposure to ETS also appears to pose risks exceeding the de manifestis risk level above which carcinogens are strictly regulated by the federal government.