Intention to Switch to Smokeless Tobacco Use among South African Smokers: Results from the 2007 South African Social Attitudes Survey

Background

Some smokeless tobacco products (SLT) have been shown to be associated with only a fraction of the risks of cigarettes. This study assessed South African smokers’ interest in switching to a hypothetical reduced harm SLT product.

Methods

The 2007 South African Social Attitudes Survey was analysed for 678 exclusive cigarette smokers. Respondents were asked about their perceptions about relative harm of snuff compared to cigarettes, and their interest in switching to snuff if informed it was 99% less harmful than cigarettes.

Results

About 49.7% of exclusive cigarette smokers believed that snuff was equally as harmful as cigarettes; 12.9% thought snuff was more harmful; 5.7% thought snuff was less harmful; while 31.8% did not know if there was a difference in harm between snuff and cigarettes. Approximately 24.2% of exclusive cigarette smokers indicated interest in switching to snuff, with significantly greater interest observed among those exposed to 100% smoke-free work environment. Interest in switching was highest (34.7%) among smokers who believed a priori that using snuff was more harmful than cigarettes, and lowest (14.5%) among those who did not know if there was a difference in harm. In a multi-variable adjusted logistic regression model, this latter group remained less likely to be interested in harm reduction switching (adjusted odds ratio = 0.42; 95% CI: 0.19–0.91).

Conclusion

About a quarter of smokers indicated interest in harm reduction switching to snuff. SLT products have a potential role in reducing the harm from smoking in South Africa, but only if they are not used to circumvent smoke-free laws that have been associated with reduced smoking.     

Prevalence and Patterns of Tobacco Use in Bangladesh from 2009 to 2012: Evidence from International Tobacco Control (ITC) Study

Background

Smoking and passive smoking are collectively the biggest preventable cause of death in Bangladesh, with major public health burden of morbidity, disability, mortality and community costs. The available studies of tobacco use in Bangladesh, however, do not necessarily employ nationally representative samples needed to monitor the problem at a national scale. This paper examines the prevalence and patterns of tobacco use among adults in Bangladesh and the changes over time using large nationally representative comparable surveys.

Methods

Using data from two enumerations of the International Tobacco Control (ITC) Bangladesh Project conducted in 2009 and 2012, prevalence estimates are obtained for all tobacco products by socio-economic determinants and sample types of over 90,000 individuals drawn from over 30,000 households. Household level sample weights are used to obtain nationally representative prevalence estimates and standard errors. Statistical tests of difference in the estimates between two time periods are based on a logistic regression model that accounts for the complex sampling design. Using a multinomial logit model, the time trend in tobacco use status is identified to capture the effects of macro level determinants including changes in tobacco control policies.

Results

Between 2009 and 2012, overall tobacco use went down from 42.4% to 36.3%. The decline is more pronounced with respect to smokeless tobacco use than smoking. The prevalence of exclusive cigarette smoking went up from 7.2% to 10.6%; exclusive bidi smoking remained stable at around 2%; while smoking both cigarette and bidi went down from 4.6% to 1.8%; exclusive smokeless tobacco use went down from 20.2% to 16.9%; and both smokeless tobacco use and smoking went down from 8.4% to 5.1%. In general, the prevalence of tobacco use is higher among men, increases from younger to older age groups, and is higher among poorer people. Smoking prevalence is the highest among the slum population, followed by the tribal population, the national population and the border area population, suggesting greater burden of tobacco use among the disadvantaged groups.

Conclusions

The overall decline in tobacco use can be viewed as a structural shift in the tobacco market in Bangladesh from low value products such as bidi and smokeless tobacco to high value cigarettes, which is expected with the growth in income and purchasing power of the general population. Despite the reduction in overall tobacco use, the male smoking prevalence in Bangladesh is still high at 37%. The world average of daily smoking among men is 31.1%. The Tobacco Control Act 2005 and the Amendment have yet to make a significant impact in curbing tobacco usage in Bangladesh. The findings in this paper further suggest that the tobacco control policies in Bangladesh need to include targeted interventions to restrain the use of particular types of tobacco products among specific demographic and socio-economic groups of the population, such as smoked tobacco among men, smokeless tobacco among women, and both smoked and smokeless tobacco among those living in rural areas, those in low socio-economic status and those belonging to the tribal and the slum population.     

Tobacco and myocardial infarction: is snuff less dangerous than cigarettes?

OBJECTIVE--To estimate the risk of myocardial infarction in snuff users, cigarette smokers, and non-tobacco users in northern Sweden, where using snuff is traditional. DESIGN--Case-control study. SETTING--Northern Sweden. SUBJECTS--All 35-64 year old men who had had a first myocardial infarction and a population based sample of 35-64 year old men who had not had an infarction in the same geographical area. MAIN OUTCOME MEASURE--Tobacco consumption (regular snuff dipping, regular cigarette smoking, non-tobacco use) and risk of acute myocardial infarction. RESULTS--59 of 585 (10%) patients who had a first myocardial infarction and 87 of 589 (15%) randomly selected men without myocardial infarction were non-smokers who used snuff daily. The age adjusted odds ratio for myocardial infarction was 0.89 (95% confidence interval 0.62 to 1.29) for exposure to snuff and 1.87 (1.40 to 2.48) for cigarette smoking compared with non-tobacco users, showing an increased risk in smokers but not in snuff dippers. Regular cigarette smokers had a significantly higher risk of myocardial infarction than regular snuff dippers (age adjusted odds ratio 2.09; 1.39 to 3.15). Smoking, but not snuff dipping, predicted myocardial infarction in a multiple logistic regression model that included age and level of education. CONCLUSIONS--In middle aged men snuff dipping is associated with a lower risk of myocardial infarction than cigarette smoking.     

Associations of Cannabis and Cigarette Use with Depression and Anxiety at Age 18: Findings from the Avon Longitudinal Study of Parents and Children

Introduction

Substance use is associated with common mental health disorders, but the causal effect of specific substances is uncertain. We investigate whether adolescent cannabis and cigarette use is associated with incident depression and anxiety, while attempting to account for confounding and reverse causation.

Methods

We used data from ALSPAC, a UK birth cohort study, to investigate associations between cannabis or cigarettes (measured at age 16) and depression or anxiety (measured at age 18), before and after adjustment for pre-birth, childhood and adolescent confounders. Our imputed sample size was 4561 participants.

Results

Both cannabis (unadjusted OR 1.50, 95% CI 1.26, 1.80) and cigarette use (OR 1.37, 95% CI 1.16, 1.61) increased the odds of developing depression. Adjustment for pre-birth and childhood confounders partly attenuated these relationships though strong evidence of association persisted for cannabis use. There was weak evidence of association for cannabis (fully adjusted OR 1.30, 95% CI 0.98, 1.72) and insufficient evidence for association for cigarette use (fully adjusted OR = 0.97, 95% CI 0.75, 1.24) after mutually adjusting for each other, or for alcohol or other substance use. Neither cannabis nor cigarette use were associated with anxiety after adjustment for pre-birth and childhood confounders.

Conclusions

Whilst evidence of association between cannabis use and depression persisted after adjusting for pre-term and childhood confounders, our results highlight the difficulties in trying to estimate and interpret independent effects of cannabis and tobacco on psychopathology. Complementary methods are required to robustly examine effects of cannabis and tobacco on psychopathology.     

Relationships between substance abuse/dependence and psychiatric disorders based on polygenic scores

Genetic susceptibility to substance use disorders (SUDs) is partially shared between substances. Heritability of any substance dependence, estimated as 54%, is partly explained by additive effects of common variants. Comorbidity between SUDs and other psychiatric disorders is frequent. The present study aims to analyze the additive role of common variants in this comorbidity using polygenic scores (PGSs) based on genome‐wide association study discovery samples of schizophrenia (SCZ), bipolar disorder, attention‐deficit/hyperactivity disorder, autism spectrum disorder, major depressive disorder and anxiety disorders, available from large consortia. PGSs were calculated for 534 patients meeting DSM‐IV criteria for dependence of a substance and abuse/dependence of another substance between alcohol, tobacco, cannabis, cocaine, opiates, hypnotics, stimulants, hallucinogens and solvents; and 587 blood donors from the same population, Iberians from Galicia, as controls. Significance of the PGS and percentage of variance explained were calculated by logistic regression. Using discovery samples of similar size, significant associations with SUDs were detected for SCZ PGS. SCZ PGS explained more variance in SUDs than in most psychiatric disorders. Cross‐disorder PGS based on five psychiatric disorders was significant after adjustment for the effect of SCZ PGS. SCZ PGS was significantly higher in women than in men abusing alcohol. Our findings indicate that SUDs share genetic susceptibility with SCZ to a greater extent than with other psychiatric disorders, including externalizing disorders such as attention‐deficit/hyperactivity disorder. Women have lower probability to develop substance abuse/dependence than men at similar PGS probably because of a higher social pressure against excessive drug use in women.     

Global methylation profiles in buccal cells of long-term smokers and moist snuff consumers

Abstract

Purpose: Alternations in gene methylation and other epigenetic changes regulate normal development as well as drive disease progression. The aim of this study is to investigate global methylation changes in the buccal cells of smokers and smokeless tobacco users.

Materials and methods: Generally healthy adult male subjects were recruited into smoker (SMK), moist snuff consumer (MSC) and non-tobacco consumer (NTC) cohorts (40 subjects/cohort) (ClinicalTrials.gov Identifier: NCT01923402). Global methylation profiling was performed on Illumina 450?K methylation arrays using buccal cell DNAs.

Results: The SMK cohort exhibited larger qualitative and quantitative changes relative to MSC. Approximately half of the differentially methylated 1252 gene loci were grouped as combustible tobacco-related (CTR) signatures and a third of the changes, tobacco-related (TR) signatures, were associated with smoking. Very few (41) differentially methylated gene loci were exclusively associated with moist snuff use and were designated as moist snuff-related (MSR) signature. Pathway enrichment analyses revealed that developmental and immune response pathways, among others, were impacted due to tobacco use.

Conclusions: Chronic cigarette smoking causes hyper- and hypo-methylation of genes that could contribute to smoking-related diseases. These results help place combustible and non-combustible tobacco products along a risk continuum and provide additional insights into the effects of tobacco consumption.     

Tobacco and pregnancy: overview of exposures and effects

This opening article will review the epidemiology of the effects of cigarette smoking and other forms of tobacco exposure on human development. Sources of exposure described include cigarettes and other forms of smoked tobacco, secondhand (environmental) tobacco smoke, several forms of smokeless tobacco, and nicotine from nicotine replacement therapy. Exposure is immense and worldwide, most of it due to smoking, but in some parts of the world and in some populations, smoking is exceeded by smokeless tobacco use. Nicotine and carbon monoxide exposure are of large concern, but cigarette smoke contains over 4000 chemical constituents and additives including known carcinogens, toxic heavy metals, and many chemicals untested for developmental toxicity. The impact of tobacco on human development will be reviewed. Fertility, conception, survival of the conceptus, most phases and aspects of development studied to date, as well as postnatal survival and health are adversely impacted by maternal tobacco use or exposure. Effects in surviving offspring are probably life-long, and are still being elucidated. It is hoped that this review and those to follow in this issue will serve to keep a focus on the critical and continuing problem of tobacco use impacting human development.     

Maternal Snuff Use and Smoking and the Risk of Oral Cleft Malformations - A Population-Based Cohort Study

Objective

To determine if maternal use of snuff (containing high levels of nicotine, low levels of nitrosamines and no combustion products) is associated with an increased risk of oral cleft malformations in the infant and whether cessation of snuff use or smoking before the antenatal booking influences the risk.

Method

A population-based cohort study was conducted on all live born infants, recorded in the Swedish Medical Birth Register from 1999 through 2009 (n = 1 086 213). Risks of oral clefts were evaluated by multivariate logistic regression analyses (using adjusted odds ratios, with 95% confidence intervals [CI]).

Results

Among 975 866 infants that had information on maternal tobacco use, 1761 cases of oral clefts were diagnosed. More than 50% of the mothers who used snuff or smoked three months prior pregnancy stopped using before the antenatal booking. Almost 8% of the mothers were smoking at the antenatal booking and 1,1% of the mothers used snuff. Compared with infants of non-tobacco users, the adjusted odds ratios (95% CI) of any oral cleft for infants of mothers who continued to use snuff or to smoke were 1.48 [1.00–2.21] and 1.19 [1.01–1.41], respectively. In contrast, in infants of mothers who stopped using snuff or stopped smoking before the antenatal booking, the corresponding risks were not increased (adjusted odds ratios [95% CI] were 0.71 [0.44–1.14] and 0.88 [0.73–1.05], respectively).

Conclusion

Maternal snuff use or smoking in early pregnancy is associated with an increased risk of oral clefts. Infants of mothers who stopped using snuff or stopped smoking before the antenatal booking had no increased risk of oral cleft malformations. Oral snuff or other sources of nicotine should not be recommended as an alternative for smoke-cessation during pregnancy.     

'Offensive' snakes: cultural beliefs and practices related to snakebites in a Brazilian rural settlement

The harmful outcomes of nicotine self administration have been the focus of sustained global health education campaigns that have targeted tobacco smoking and to a lesser extent, smokeless tobacco use. 'Smokeless tobacco' infers that the nicotine is not burnt, and administration can be through a range of methods including chewing. The chewing of wild tobacco plants (Nicotiana spp.) is practiced across a broad inland area of Central Australia by traditional Aboriginal groups. Collectively these plants are known by a variety of names - one common name being 'pituri'. This is the first paper to examine the historical literature and consider the linkage between pituri use and health outcomes. Using a narrative approach, this paper reviews the literature generated since 1770 surrounding the term pituri and the behaviours associated with its use. The review examines the scientific literature, as well as the diaries and journals of nineteenth century explorers, expedition notes, and early Australian novels to expound the scientific evidence and broaden the sense of understanding related to pituri, particularly the behavioural elements. The evaluation considers the complexities of ethnobotany pertaining to language and distance and the ethnopharmacology of indigenous plant usage. The review compares the use of burnt and smokeless tobacco to pituri and establishes the foundation for research into the clinical significance and health outcomes of pituri use. Additionally, this review provides contemporary information for clinicians providing care for patients who chew pituri.     

Alcohol,tobacco and cannabis use among Nova Scotia adolescents: implications for prevention and harm reduction

OBJECTIVE: To characterize adolescent drug use in terms of a risk continuum and to explore the rationale for harm reduction as a potential approach for school-based drug prevention. DESIGN: Self-reported surveys, in 1991 and 1996, of adolescent students concerning their use of drugs, especially alcohol, tobacco and cannabis, and the harmful consequences of such use. SETTING: Nova Scotia. PARTICIPANTS: A total of 3452 (in 1991) and 3790 (in 1996) junior and high school students in randomly selected classes in the public school system. OUTCOME MEASURES: Prevalence of drug use and patterns of multiple drug use and of alcohol- and drug-related problems; independent risk factors for multiple drug use. The risk continuum for the response to alcohol problems was used as a policy framework. RESULTS: The prevalence of cigarette smoking and the use of hallucinogens and stimulants was markedly higher in 1996 than in 1991. Over one-fifth (21.9%) of the students reported multiple drug use of alcohol and tobacco and cannabis in the 12 months before the 1996 survey. The 3 main subgroups--nonusers, users of alcohol only and users of multiple drugs--had distinct patterns of use, numbers of problems and risk factors. In all, 27.1% of the students had experienced at least 1 alcohol-related problem and 6% had experienced at least 1 drug-related problem in the 12 months before the 1996 survey. CONCLUSION: There is a need for integrated school- and community-based drug prevention programs, with goals, strategies and outcome measures capturing the full spectrum of patterns of use and levels of risk among subgroups of the adolescent student population.     

Serum total sialic acid levels in smokers and users of smokeless tobacco in form of oral powder (Maraş powder)

Summary Smokeless tobacco (ST) is widely used as chewing tobacco and as oral snuff in the world. Also, in Kahramanmaraş, a city in Southern Turkey, ST used as ‘oral powder’ or ‘Maraş Powder’ is consumed widely instead of cigarette smoking. The aim of this study was to search the effect of ST use on serum total sialic acid (TSA) and to compare the serum TSA levels in smokers and ST users. The study was performed at the Department of Chemistry-Biochemistry, University of Kahramamaraş Sutcu Imam, Turkey, in 2003. Serum samples obtained from smokers (Group I), Maraş powder users (Group II), and healthy control subjects (Group III) who were nonsmokers and nonusers ST. Individuals who were smokers and ST users were classified into subgroups with respect to amount of consumed cigarette or oral powder. Serum TSA was measured with the Denny’s colorimetric method. The TSA concentrations were significantly higher in the sera of smokers (p < 0.001) and Maraş powder users (p < 0.001) than those of control subjects. The mean serum TSA level was found to be lowest in the control group and highest in the Maraş Powder users. But, there was no significant difference in serum TSA levels between smokers and Maraş powder users (p > 0.05). We can conclude from the results obtained that serum TSA was affected by ST use as seen in smokers. This finding may be an indication of harmful effects of ST use as Maraş powder as well as cigarette smoking.     

Patterns and associations of smoking and electronic cigarette use among survivors of tobacco related and non-tobacco related cancers: A nationally representative cross-sectional analysis

BackgroundTobacco-use among cancer survivors leads to preventable morbidity, mortality, and increased healthcare costs. We sought to explore the prevalence of smoking and e-cigarette use among survivors of tobacco and non-tobacco related cancers.MethodsA cross-sectional analysis was conducted using the 2015–2018 National Health Interview Survey. Our primary outcome was the prevalence of current cigarette smoking or e-cigarette use among adults with self-reported history of tobacco related or non-tobacco related cancer. Logistic regression analysis was to assess the association of reported cancer type with cigarette smoking or e-cigarette use. Secondary outcomes included yearly trends and dual use.ResultsA total of 12,984 respondents reported a history of cancer, representing a weighted estimate of 5,060,059 individuals with a history of tobacco-related malignancy and 17,583,788 with a history of a tobacco and non-tobacco related cancer, respectively. Survivors of tobacco-related cancers had a significantly higher prevalence of current cigarette use (18.2 % vs 9.7 %, P < 0.0001), e-cigarette use (2.7 % vs 1.6 %, P < 0.0001) and similar rates of dual use. The prevalence of cigarette smoking among all survivors increased as time increased from the year of diagnosis up to 2 years post-diagnosis (P = 0.047). Odds of reporting current cigarette smoking use was higher for survivors of tobacco-related cancers, adjusted for sociodemographic factors (OR1.69, 95 % CI 1.44−1.99).ConclusionsSurvivors of tobacco-related cancers have a higher prevalence of current cigarette smoking and e-cigarette use compared to survivors of non-tobacco related cancers. There was a sequential increase in the prevalence of cigarette use during each subsequent year from the time of a new cancer diagnosis, underscoring the need for long term tobacco cessation support among newly diagnosed adults with cancer.     

Chromium Exposure in the Adult Population,Consuming Different Types of Smokeless Tobacco Products in Pakistan

The pervasive smokeless tobacco (SLT) consumption and diseases related to its use is a hot topic for the public discussion. In this study, concentrations of chromium (Cr) were measured in different SLT products [snuff (dry and moist), mainpuri, and gutkha] offered and used in Pakistan. The current study was also designed to assess the Cr levels in the biological (scalp hair and blood) samples of male and female subjects, age ranged from 25 to 60 years, chewing different SLT products. For comparative purpose, the healthy persons of the same age group, who did not consume any SLT products, were selected as referents. The concentrations of Cr in SLT products and biological samples were measured by electrothermal atomic absorption spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by certified reference materials (CRMs). The resulted data indicated that the adult persons, who consumed different SLT products, have 2–3 fold higher levels of Cr in biological samples as compared to referent subjects (p < 0.01). The persons, who chew/sniff different SLT products, have 50–80 and 42–82 % higher levels of Cr in their scalp hair and blood samples as related to referents. The daily intake of Cr is lower as compared to the recommended value of 50–200 μg/day. It was expected that 10 g consumption of various kinds of SLT products (snuff, mainpuri, and gutkha) may subsidize 21.2–220, 17.7–122, and 18.4–273 % of the recommended daily intake of Cr, respectively.     

Mechanisms underlying the link between cannabis use and prospective memory

While the effects of cannabis use on retrospective memory have been extensively examined, only a limited number of studies have focused on the links between cannabis use and prospective memory. We conducted two studies to examine the links between cannabis use and both time-based and event-based prospective memory as well as potential mechanisms underlying these links. For the first study, 805 students completed an online survey designed to assess cannabis consumption, problems with cannabis use indicative of a disorder, and frequency of experiencing prospective memory failures. The results showed small to moderate sized correlations between cannabis consumption, problems with cannabis use, and prospective memory. However, a series of mediation analyses revealed that correlations between problems with cannabis use and prospective memory were driven by self-reported problems with retrospective memory. For the second study, 48 non-users (who had never used cannabis), 48 experimenters (who had used cannabis five or fewer times in their lives), and 48 chronic users (who had used cannabis at least three times a week for one year) were administered three objective prospective memory tests and three self-report measures of prospective memory. The results revealed no objective deficits in prospective memory associated with chronic cannabis use. In contrast, chronic cannabis users reported experiencing more internally-cued prospective memory failures. Subsequent analyses revealed that this effect was driven by self-reported problems with retrospective memory as well as by use of alcohol and other drugs. Although our samples were not fully characterized with respect to variables such as neurological disorders and family history of substance use disorders, leaving open the possibility that these variables may play a role in the detected relationships, the present findings indicate that cannabis use has a modest effect on self-reported problems with prospective memory, with a primary problem with retrospective memory appearing to underlie this relationship.     

Relationships of Psychiatric Disorders with Overweight and Obesity in an Adult General Population**

Objective: To explore relationships of smoking and risk drinking status, nicotine and alcohol dependence, and anxiety, depressive, and somatoform disorders with overweight and obesity. Research Methods and Procedures: A probability sample was drawn that was representative for the adult general population, 18 to 64 years of age, in one region of Germany; the participation rate was 70.2%. After excluding those who were pregnant or had a current eating disorder according to the DSM‐IV, 4063 individuals remained. Overweight and obesity were defined according to the BMI that was assessed in the face‐to‐face in‐home standardized interview (Composite International Diagnostic Interview) on psychiatric disorders. Results: Men with a former nicotine dependence had higher odds of being overweight than men who never had a nicotine dependence (adjusted odds ratio, 1.5; confidence interval, 1.1 to 2.1). Men at current risk for drinking and current alcohol‐dependent or abusing men had lower odds of being overweight compared with men who never were alcohol dependent, abusing, or at risk for drinking (adjusted odds ratio, 0.3; confidence interval, 0.8 to 0.9). Effect sizes were small. No relationship of overweight with depressive, anxiety, or somatoform disorders was found in the multivariate analysis. Discussion: There is a relationship between being overweight and nicotine and alcohol dependence or abuse among men but not among women. Even though one reason for women to refrain from quitting smoking is the fear of weight gain, these results do not support this. This information could help convince women to try to quit smoking.     

Tobacco Use and Mass Media Utilization in Sub-Saharan Africa

BackgroundMedia utilization has been identified as an important determinant of tobacco use. We examined the association between self-reported tobacco use and frequency of mass media utilization by women and men in nine low-to middle-income sub-Saharan African countries.ResultsThe risk of cigarette smoking increased with greater utilization to mass media. The use of smokeless tobacco and tobacco use in general declined with greater utilization to mass media. The risk of tobacco use was 5% lower in women with high media utilization compared to those with low media utilization [Adjusted Odds Ratio (AOR) = 0.95, 95% confidence interval (CI):0.82–1.00]. Men with a high media utilization were 21% less likely to use tobacco compared to those with low media utilization [AOR = 0.79, 95%CI = 0.73–0.85]. In the male sample, tobacco use also declined with the increased frequency of reading newspapers (or magazines), listening to radio and watching television.ConclusionsMass media campaigns, conducted in the context of comprehensive tobacco control programmes, can reduce the prevalence of tobacco smoking in sub-Saharan Africa. The reach, intensity, duration and type of messages are important aspects of the campaigns but need to also address all forms of tobacco use.     

Mutagen levels in urine from snuff users, cigarette smokers and non tobacco users--a comparison

The mutagenic activity of concentrates of urine from snuff users, cigarette smokers and non tobacco users has been investigated. A concentration procedure involving use of Sep-Pak C18 columns and elution with methylene chloride was used. The concentrates were assayed for mutagenicity towards strain TA98 of Salmonella typhimurium, both in the presence and absence of a metabolic activation system, the post-mitochondrial liver fraction (S9) from Aroclor 1254 induced rats. The mean mutagenic activity of smokers' urine concentrates was 8.6 X 10(3) revertants per 24 h and significantly higher than the corresponding values for snuff users, abstinent snuff users and non tobacco users, which were (1.3, 1.3 and 0.9) X 10(3), respectively. No significant difference in mutagenic activity was found between urine from snuff users, whether using or abstaining from snuff, and urine from non tobacco users. It could thus be concluded that the level of urinary mutagens, isolated by adsorption on Sep-Pak C18 columns, is not elevated by habitual usage of Swedish wet snuff.     

Characterization of Bacterial Communities in Selected Smokeless Tobacco Products Using 16S rDNA Analysis

The bacterial communities present in smokeless tobacco (ST) products have not previously reported. In this study, we used Next Generation Sequencing to study the bacteria present in U.S.-made dry snuff, moist snuff and Sudanese toombak. Sample diversity and taxonomic abundances were investigated in these products. A total of 33 bacterial families from four phyla, Actinobacteria, Firmicutes, Proteobacteria and Bacteroidetes, were identified. U.S.-produced dry snuff products contained a diverse distribution of all four phyla. Moist snuff products were dominated by Firmicutes. Toombak samples contained mainly Actinobacteria and Firmicutes (Aerococcaceae, Enterococcaceae, and Staphylococcaceae). The program PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) was used to impute the prevalence of genes encoding selected bacterial toxins, antibiotic resistance genes and other pro-inflammatory molecules. PICRUSt also predicted the presence of specific nitrate reductase genes, whose products can contribute to the formation of carcinogenic nitrosamines. Characterization of microbial community abundances and their associated genomes gives us an indication of the presence or absence of pathways of interest and can be used as a foundation for further investigation into the unique microbiological and chemical environments of smokeless tobacco products.     

Modeling the Potential Effects of New Tobacco Products and Policies: A Dynamic Population Model for Multiple Product Use and Harm

Background

Recent declines in US cigarette smoking prevalence have coincided with increases in use of other tobacco products. Multiple product tobacco models can help assess the population health impacts associated with use of a wide range of tobacco products.

Methods and Findings

We present a multi-state, dynamical systems population structure model that can be used to assess the effects of tobacco product use behaviors on population health. The model incorporates transition behaviors, such as initiation, cessation, switching, and dual use, related to the use of multiple products. The model tracks product use prevalence and mortality attributable to tobacco use for the overall population and by sex and age group. The model can also be used to estimate differences in these outcomes between scenarios by varying input parameter values. We demonstrate model capabilities by projecting future cigarette smoking prevalence and smoking-attributable mortality and then simulating the effects of introduction of a hypothetical new lower-risk tobacco product under a variety of assumptions about product use. Sensitivity analyses were conducted to examine the range of population impacts that could occur due to differences in input values for product use and risk. We demonstrate that potential benefits from cigarette smokers switching to the lower-risk product can be offset over time through increased initiation of this product. Model results show that population health benefits are particularly sensitive to product risks and initiation, switching, and dual use behaviors.

Conclusion

Our model incorporates the variety of tobacco use behaviors and risks that occur with multiple products. As such, it can evaluate the population health impacts associated with the introduction of new tobacco products or policies that may result in product switching or dual use. Further model development will include refinement of data inputs for non-cigarette tobacco products and inclusion of health outcomes such as morbidity and disability.