Genotoxic effects of waterpipe smoking on the buccal mucosa cells

Does waterpipe smoke induce genotoxicity (DNA damage) in mammalian cells in vivo? A systematic review

The waterpipe works by placing tobacco in a bowl with holes at the bottom, which is connected to a tube leading to a water-filled container. Upon heating the tobacco product with hot charcoal placed atop it, the emanating smoke is inhaled by the user via a hose linked to the water receptacle. The aim of this literature review is to evaluate whether the use of waterpipes can indeed induce genotoxicity in mammalian cells in vivo. Additionally, the study aims to assess the quality of the included research articles on this topic to ensure the reliability of the findings. We performed comprehensive searches in PubMed, SCOPUS, and Web of Science to identify relevant articles published until July 2024. The findings confirmed that waterpipe smoke induces genetic damage. This assertion is supported by the fact that 11 studies (out of 15) received a Strong or Moderate assessment categorization, suggesting that the majority of studies adhered to most technical standards, thereby enhancing the reliability of the research findings. Regarding the types of DNA damage reported, DNA strand breaks, chromosome damage and oxidative DNA damage were found in this review. Taken together, this study holds significant importance in assessing the efficacy of genotoxicity assays in detecting DNA damage due to waterpipe smoke and the comet and micronucleus assays are suitable biomarkers for biomonitoring people who use waterpipe.

Evaluation of micronuclei, cytomorphometric and cytologic changes of the oral mucosa in hookah and cigarette smokers

OBJECTIVE

To analyze the effect of hookah and cigarettes on the oral mucosa of smokers through the use of exfoliative cytology.

STUDY DESIGN

Smear samples were collected by exfoliative cytology from the tongue of 33 hookah smokers, 22 cigarette smokers, and 30 non-smokers. The selected analyses include micronuclei (MN), metanuclear anomalies, epithelial maturation, and cytomorphology (nuclear area [NA], cytoplasmic area [CA], and NA/CA ratio).

RESULTS

The largest differences observed for MN and metanuclear anomalies were between cigarette smokers and the control group (notably 1 MN P = .04; total cells with MN P = .039; total MN P = .042; karyorrhexis and binucleation, P = .0001). The hookah group, compared with the control group, showed the greatest differences for karyolysis (P = .0023), binucleation (P = .0003), and broken egg (P = .008). Significant differences were found between the smokers and the control groups regarding changes in the superficial cell without nucleus, perinuclear halo, vacuolization, color change, mucus, and keratohyalin granules. There was a significant increase in the NA and NA/CA ratio in the smoker groups.

CONCLUSION

This study showed that a combined analysis of exfoliative cytology associated with other diagnostic methods is a useful tool for studying oral carcinogenesis. Hookah and cigarettes showed similar effects in terms of displaying substantial cytogenetic and cytotoxic damage.

Genotoxicity of waterpipe smoking in young adults from Sarajevo, Bosnia & Herzegovina

Background

Waterpipe, also known as a hookah or narghile, is a type of tobacco products consumption device. Recently it has been increasingly popular in Bosnia and Herzegovina and the region. Waterpipe consumers are predominantly adolescents and young adults. Many of them believe in slighter harmful effects of waterpipes, compared to cigarettes. We aimed to determine the DNA damage in oral leukocytes and buccal cells of young individuals who have smoked a waterpipe for more than one year.

Methods

The study group consisted of 40 cigarette non-smokers who regularly smoked a waterpipe on average of once per week. As a control, 40 non-smoking individuals were selected to match smokers for age. All participants in the study were healthy male and female adults from Bosnia and Herzegovina, 18-30 years of age. Before sampling, detailed survey and informed consent have been provided by each participant. Comet assay in oral leukocytes and buccal micronucleus cytome (BMCyt) assay in exfoliated buccal cells were applied.

Results

Almost half of waterpipe smokers (WPS) tasted waterpipe at 15-16 years of age. Comet assay analysis showed increased tail intensity, tail length, and tail moment values among WPS compared to non-smokers (NS) (p = 0.0001, p = 0.0067, and p = 0.0001, respectively). Frequencies of the micronucleated (p = 0.0004), binucleated (p = 0.01), karyorrhectic, (p = 0.0036), and pycnotic cells (p = 0.03) were significantly higher in WPS compared to NS group.

Conclusions

Genotoxicity and DNA damage biomarkers were increased in oral leukocytes and exfoliated buccal cells of young waterpipe smokers from Bosnia and Herzegovina, compared to NS group.

Cytotoxic and Genotoxic Effects of Waterpipe on Oral Health Status: Systematic review and meta-analysis

This systematic review and meta-analysis aimed to assess the cytotoxic and genotoxic impacts of waterpipe smoking on oral health. The databases MEDLINE, Cochrane Library and Dimensions were searched to find studies evaluating whether waterpipe smokers exhibited any cytotoxic or genotoxic effects on their oral cells compared to non-smokers, with regard to mouth neoplasms. Particularly, changes in DNA methylation and p53 expression were assessed. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were adopted for the systematic review. Review Manager was utilised for statistical analysis with a significance level at P <0.05. To assess the grades of the included articles, a risk of bias analysis was summarised. A forest plot, including some of the included articles included, was created regarding the different grades. A total of 20 studies were included in this review. The results showed that waterpipe smoking has cytotoxic and genotoxic effects on oral cells, with a risk difference of 0.16. Although the published articles are few in number, all confirm the devastating effects of waterpipe smoking related to the carcinogenicity. Waterpipe smoking is harmful to oral health. It causes a series of detrimental cellular and genetic modifications such as acanthosis, epithelial dysplasia and hyperparakeratosis. In addition, waterpipe smoke contains several carcinogenic compounds. As it releases many harmful organic compounds, waterpipe smoking increases the incidence of oral cancer.

Cytotoxic and genotoxic effects of cigarette and waterpipe tobacco smoking on buccal mucosa: A systematic review and meta-analysis

Background

Waterpipe tobacco smoking (WTS) is an issue all over the world, although it is particularly prevalent in the Middle East, and Southeast Asia. The genotoxic effects of smoking were reported to be associated with nucleus abnormalities such as micronuclei (MN), karyorrhexis (KR), karyolysis, pyknosis, binucleates, broken eggs, condensed chromatin in exfoliated buccal mucosal cells, and was believed to be associated with apoptosis of cells and was not correlated to the exposure time.

Aim

The aim of this study was to evaluate and compare the cytotoxic and genotoxic effects of cigarette and WTS on buccal mucosa.

Materials and Methods

The pertinent search was done through the computerized literature on MEDLINE, EMBASE, and PUBMED databases, which included case-control, clinical and observational studies regarding the mutagenic effects of cigarettes and WTS in oral tissues. The retraction of data in this study was undertaken from May 2010 to May 2022. A total of 60 articles from the search data were retrieved. This investigation was registered with the research center of Riyadh Elm University for institution review board approval (IRB) and obtained the IRB number "FRP/2021/448/733/707 and the systematic review registration number with respect to PROSPERO is 345417.

Results

After the removal of duplicates, 32 were evaluated for the inclusion and exclusion criteria. Out of 32 articles, twenty studies were evaluated for cytogenetic abnormalities in buccal mucosal cells of waterpipe tobacco smokers (WTS) and cigarette smokers, and 12 were excluded. The mean MN levels in the oral tissues of WTS were more (1.94 ± 0.39) than in non-smokers (1.68 ± 0.35).

Conclusion

Therefore, we conclude that the MN count can be employed as a biomarker and preliminary signal for the identification of changes in oral mucosa among smokers, which develop towards cancer formation.

Hookah Smoking among Brazilian University Students: An Exploratory Survey on the Prevalence and Perceptions of Addiction and its Harmfulness

Background

This study aimed to determine the prevalence, beliefs, attitudes, and perceptions of hookah use in a population of undergraduate students at a large public university in Brazil.

Methods

The sample consisted of 1348 undergraduate students aged over 18-year-old. They completed structured questionnaires on demographic information and close-ended questions on the past and current experiences of smoking hookah. The data underwent descriptive analysis and binary logistic regression.

Findings

Finally, 1298 valid survey forms were obtained from printed and digital questionnaires. More than half (53.9%) of participants reported having tried hookah at least once, however, only 10.8% reported they had experienced it within the last 30 days. The majority of the studied population presented acceptable beliefs about the harmfulness and addictive capacity of hookah smoking. However, when comparing the perceptions of those who had smoked and those who had never smoked hookah, and also, the perceptions of users and non-users, significant differences were observed. Students who were users or had already tried hookah showed a tendency to underestimate the deleterious effects of this type of smoking.

Conclusion

It could be concluded that hookah smoking was common among Brazilian university students. In addition, preoccupying misperceptions of hookah's harmfulness and addictive capacity were found. The results showed that the epidemic of hookah smoking, especially among young people, has spread far beyond the Arab world and the Persians. Accordingly, preventive measures must be taken if this population is to be protected from addiction and other serious health problems.

Clinical and cytological findings in oral cavity of young shisha smokers and non-smokers – a comparative study

Introduction: Shisha, a form of smoking tobacco is known to be detrimental to oral health. Yet, the effects of shisha on oral health is not well documented. Hence, this study was undertaken to compare the clinical and cytological findings in oral cavity of young shisha smokers as compared to non-smokers. Materials and methods: A cross-sectional analytical study was undertaken among 60 subjects including 30 young shisha smokers and 30 non-smokers. Clinical examination was carried out to record gingival status, periodontal status, oral hygiene and dental caries experience. Exfoliative cytology was used to study the cytological changes of buccal mucosal cells. Data was analysed using SPSS version 22. Student’s t-test, Fisher’s exact test and odd’s ration was used for comparison. p < 0.05 was considered statistically significant. Results: No significant differences were found between the groups with respect to proportion of subjects with gingivitis (p = 0.071), erosion (p = 0.085) and dental caries experience (p = 0.329). However, shisha smokers had poorer oral hygiene and more severe gingival inflammation as compared to non-smokers with p = 0.026 and p = 0.007 respectively. The odds of having atypical cells in oral mucosa among shisha smokers was 3.76 times higher than the non-smokers. Conclusion: The findings of our study showed that young shisha smokers had more atypical cells in oral mucosa as compared to their non-smoking counterparts. However, longitudinal studies are needed to affirm the findings of this study.

Comparison of Repair Index in Cigarette and Waterpipe Smokers: A Bio-Monitoring Assessment Using Human Exfoliated Buccal Mucosa Cells

BACKGROUND

Repair index (RI) using DNA changes reveals the activity of carcinogenesis. Cigarette and waterpipe smoking are important contributors to oral cavity malignancy. The RI in cigarette and waterpipe smokers has not been compared so far. The aim of this study was to compare the RI in cigarette and waterpipe smokers using the human exfoliated buccal mucosa cells.

METHODS

The exfoliated buccal mucosa cells of 60 cigarette and waterpipe smokers and 20 nonsmokers were evaluated in a case-control study. The number of micronuclei (MN), broken egg (BE), karyorrhexis (KR), and karyolysis (KL) were counted in 1000 cells from randomly selected fields. The RI = (KL + KR)/(MN + BE) was calculated and compared between subjects and controls. Data were analyzed by one-way analysis of variance (ANOVA), Tukey's Honest Significant Difference (HSD), and Spearman's correlation coefficient test at P < 0.05 probability level.

RESULTS

The difference of MN (P < 0.0001), BE (P < 0.0001), KR (P < 0.0001), and KL (P < 0.0001) count was significant between cigarette smokers, waterpipe smokers, and nonsmokers. The RI was significantly different between groups (P = 0.007). The RI was significantly higher in cigarette smokers compared to waterpipe smokers (P = 0.04) and nonsmokers (P = 0.009).

CONCLUSIONS

The RI was significantly higher in cigarette smokers compared to waterpipe smokers. The finding suggests that due to higher interrupted cellular hemostasis, the risk of carcinoma in waterpipe smokers can be greater than that in cigarette smokers.

Tobacco Use and Periodontal Disease-The Role of Microvascular Dysfunction

Periodontal disease consists in highly prevalent wide-ranging inflammatory conditions that affect the supporting apparatus of teeth. Tobacco use is the most important risk factor for periodontal disease as it increases disease severity and periodontal surgery complications. Tobacco use is harmful for the vasculature by causing microvascular dysfunction, which is known to negatively affect periodontal disease. To the author's knowledge this paper is the first comprehensive review on the mechanisms by which tobacco use affects oral microcirculation and impacts the pathophysiology of periodontal disease. In healthy subjects, acute nicotine administration or tobacco use (smoking/smokeless forms) increases the blood flow in the oral mucosa due to local irritation and increased blood pressure, which overcome neural- and endocrine-mediated vasoconstriction. Chronic tobacco smokers display an increased gingival microvascular density, which is attributed to an increased capillary recruitment, however, these microcirculatory units show higher tortuosity and lower caliber. These morphological changes, together with the repetitive vasoconstrictive insults, contribute to lower gingival perfusion in chronic smokers and do not completely regress upon smoking cessation. In periodontal disease there is considerable gingival inflammation and angiogenesis in non-smokers which, in chronic smokers, are considerably suppressed, in part due to local immune suppression and oxidative stress. Tobacco exposure, irrespective of the form of use, causes long-term microvascular dysfunction that increases the risk of complications due to the natural disease course or secondary therapeutic strategies.

Interventions to prevent periodontal disease in tobacco-, alcohol-, and drug-dependent individuals

Substance abuse affects more than one sixth of the world's population. More importantly, the nature of the abuse and the type of addictive substances available to individuals is increasing exponentially. All substances with abusive potential impact both the human immuno-inflammatory system and oral microbial communities, and therefore play a critical role in the etiopathogenesis of periodontal diseases. Evidence strongly supports the efficacy of professionally delivered cessation counseling. Dentists, dental therapists, and hygienists are ideally placed to deliver this therapy, and to spearhead efforts to provide behavioral and pharmacologic support for cessation. The purpose of this review is to examine the biologic mechanisms underlying their role in disease causation, to understand the pharmacologic and behavioral basis for their habituation, and to investigate the efficacy of population-based and personalized interventions in prevention of periodontal disease.

Comparison of Genotoxic Effect in Buccal Exfoliated Cells between Cigarette and Waterpipe Smokers

BACKGROUND/AIM

Cytogenetic biomarkers such as micronuclei (MN) are used for the evaluation of exposure to carcinogens and genotoxic effects in oral epithelial cells. Tobacco is one of the strongest carcinogens responsible for the development of cancer in oral mucosa. The aim of this study was to compare the genotoxic effect of waterpipe smoking with that of cigarette smoking.

METHODS

This case-control study was performed on 30 waterpipe smokers, 30 cigarette smokers, and 30 nonsmokers. Buccal exfoliated cells were prepared using cytobrushes and stained with the Papanicolaou technique. The cytologic slides were examined under a light microscope for counting the number of MN and the number of cells with MN per 1,000 epithelial cells.

RESULTS

The mean number ± standard deviation (SD) of MN in waterpipe smokers, cigarette smokers, and nonsmokers was 7.55 ± 5.530, 4.95 ± 5.633, and 2.00 ± 2.406, respectively. The mean number ± SD of cells with MN in waterpipe smokers, cigarette smokers, and nonsmokers was 6.20 ± 4.830, 3.50 ± 3.832, and 1.45 ± 1.701, respectively. Numbers of cells with MN differed significantly between waterpipe smokers and cigarette smokers (p = 0.04) and between waterpipe smokers and nonsmokers (p < 0.001). Numbers of MN differed significantly between waterpipe smokers and nonsmokers (p < 0.001). Numbers of MN did not differ significantly between waterpipe smokers and cigarette smokers (p = 0.10). Numbers of MN and of cells with MN did not differ significantly between cigarette smokers and nonsmokers (p = 0.06 and p = 0.052, respectively).

CONCLUSIONS

Waterpipe smoking is associated with a significantly higher frequency of MN, and it seems that waterpipe smoking has a greater genotoxic effect than cigarette smoking.

Micronucleus Assay of Buccal Mucosa Cells in Waterpipe (Hookah) Smokers: A Cytologic Study

Background & Objective

Micronucleus assay of buccal mucosa cells is a simple bio- monitoring method for diagnosing the genetic damages of toxic agents. The aim was to study the genotoxic effect of waterpipe smoking on buccal mucosa cells using micronucleus assay.

Methods

This was a case control. A total of 30 male waterpipe smokers and 30 non-smokers were included in the study. The exfoliated buccal mucosa cells were scrapped using wooden spatula and were spread over glass slides. The mean number of micronuclei was determined using Feulgen-stained slides. The number of micronuclei per 1000 cells was calculated and compared between the two groups of smokers and non-smokers.

Results

The mean number of micronuclei in waterpipe smokers and non-smokers was 1.94±0.39 and 1.68±0.35, respectively. The micronuclei count in waterpipe smokers was significantly higher than non-smokers (P=0). The difference between the number of waterpipe smoking and micronuclei count was significantly different (P=0).

Conclusion

The mean number of micronuclei in buccal mucosa cells of waterpipe smokers was significantly higher than non-smokers. The genotoxicity effect of waterpipe was dose-dependent.

Waterpipe Tobacco Chemical Content, Microbial Contamination, and Genotoxic Effects: A Systematic Review

The spread of tobacco smoking has increased over time at the global and national levels. One of the widely spread tobacco products is waterpipe. Recent studies showed that waterpipe tobacco smoke contains toxic substances, including carbon monoxide and nicotine. Some of them are genotoxic carcinogen, such as formaldehyde. This study aims to provide comprehensive insight into the types and depth of the scientific literature on waterpipe tobacco smoke chemical content, its genotoxic effects, and waterpipe device microbial contamination. We conducted a systematic comprehensive review of articles published between 1986 and December 2018. Primary research articles focusing on the content of waterpipe smoke, including chemical, genotoxic, and microbial contaminants, were eligible for inclusion. Of the 1,286 studies generated, 22 studies were included. Twenty-three chemical families were extracted from waterpipe smoke. Aldehydes were the most identified chemical family in 6 studies, and next is polycyclic hydrocarbons, found in 5 studies. About 206 chemical compounds were identified. Flavobacterium, Pseudomonas, coagulase-negative Staphylococci, and Streptococcus were the most abundant pathogen contaminants. Waterpipe smoke had elevated levels of many DNA damage markers (8-hydroxy-2′-deoxyguanosine and cytochrome P450 1A1) and inhibited levels of many DNA repair genes ( OGG1 and XRCC1) in waterpipe smokers. Waterpipe smoke is associated with the genotoxic effect, which elevates the levels of many DNA damage markers and inhibits the levels of many DNA repair genes. In addition, waterpipe smoking can expose smokers to a range of pathogenic bacteria.

The Effect of Hookah Use on Buccal Mucosa: Evaluation of Repair Index

Background and aim:

Cigarettes, hookah, and tobacco are the most important etiologic factors for oral cancers and dysplastic lesions. This study was undertaken to determine the correlation between hookah use and the percentage of cells with micronucleus, karyorrhexis, karyolysis, and broken egg in the buccal mucosa; and secondly to compare hookah user and non-user in terms of repair index.

Materials and methods:

The present historical cohort study was carried out on 72 samples taken from 36 hookah users and 36 control subjects. Smear samples were obtained from participants’ buccal mucosa for cytological evaluation using Papanicolaou technique. Then, the percentages of cells with micronucleus, karyorrhexis, karyolysis, and broken egg were recorded and the repair index was calculated. Data were analyzed using Mann-Whitney U test.

Results:

A total of 72 samples taken from 36 hookah users and 36 control subjects were evaluated. The means of micronucleus scores in the buccal mucosa cells of hookah users and controls were 10.7±2.6 and 5.8±2.0, the karyorrhexis scores in the hookah users and controls were 0.1±0.06 and 0.04±0.06, and the karyolysis scores in hookah users and controls were 0.16±0.05 and 0.08±0.06, respectively. These differences were statistically significant between hookah users and controls (P<0.001). The broken egg score was 0.66±0.07 for the hookah users and 0.03±0.04 for the control group, revealing a statistically significant difference (P<0.036). Finally, the repair index values were 0.03±0.01 and 0.05±0.13 in hookah users and controls, respectively. This difference was also significant (P<0.026).

Conclusion:

The percentages of cells with micronucleus, karyorrhexis, karyolysis, and broken egg in the buccal mucosa of hookah users were significantly higher than those in control group; in addition, the repair index of the buccal mucosa cells in hookah users was significantly lower than that in the control group.

p53 Overexpression in Oral Mucosa in Relation to Shisha Smoking in Syria and Lebanon

Introduction

Shisha (waterpipe) smoking is becoming a very prevalent form of tobacco consumption in the Middle east and use is growing over the world. Smoking-related malignancies have a high genome-wide burden of mutations, including examples in the gene encoding p53.

Aims

To investigate alterations in p53 immunohistochemical expression in the normal, pre-malignant, malignant oral mucosa in relation to Shisha smoking habits.

Materials and Methods

A total of 105 paraffin embedded tissue sections of OSCCs (52 smokers,53 non-smokers), 96 of premalignant lesions (48 smokers,48 non-smokers) and 60 normal oral mucosa. Some 30 patients with a history of Shisha smoking daily for more than 5 years were also investigated for mutant expression of p53. Tissue samples were considered positive for p53 staining when any positive cells of epithelial origin could be detected.

Results

The majority (74.3%) of oral squamous cell carcinomas showed positive staining for p53 expression (83.1% and 65.5% with Shisha smokers and non-smokers, respectively). In the 96 premalignant lesions, about 23% from non-smokers and 41.7% from smokers showed p53 positivity. In normal epithelium, P53 positive cells were noted in 6.6% of non-smokers and 16.6% of smokers. Positive correlations with Shisha smoking were evident for the following groups: WDOSCC, MDOSCC, mild dysplasia G1, moderate dysplasia G2 and in normal mucosa using Student’s t- test, P value<0.05.

Conclusion

These results strongly suggest that p53 mutations are associated with Shisha smoking in OSCC, pre-malignant lesions and normal mucosa of the oral cavity.

Cytological multimarker screening using BMCyt test in waterpipe smokers: an integrative study of cell damage, toxicological and cancer risk

Waterpipe smoking is an ancient method of tobacco smoking practiced worldwide. There is a common belief that waterpipe smoking is a safer alternative to cigarette, but many studies showed that some toxicants were associated with cancer risk, significantly higher in waterpipe smoking. Thus, this study aimed to evaluate the status of waterpipe smoker's buccal cells and its cancer risk using the buccal micronucleus cytome test. Forty waterpipe smokers (noncigarette smokers) were recruited and paired by gender, age and alcoholic habits with 40 control subjects. One-thousand cells from each individual were analysed and the number of pyknotic cells (PYC), karyolitic cells (KYL), karyorrhetic cells (KHC), condensed chromatin (CC), binucleated cells (BN), basal cells (BC), nuclear buds (NBUD) and differentiated cells (DIFF) were counted. Additionally, 2000 differentiated cells were analysed counting micronucleated cells (MNi) and nuclear buds. We observed an increasing P< 0.05 in all waterpipe smoker's cell parameters, except DIFF (fold-decrease). Only CC showed no differences between groups. The interference in the cell cycle plus DNA damage observed in this study could be responsible for the high number of damaged cells and in death process, showing the importance of our study and the high risk in waterpipe smoking.

The effect of chronic exposure to waterpipe tobacco smoke on airway inflammation in mice

PURPOSE

Acute exposure of experimental animals to waterpipe tobacco smoke has been shown to induce lung inflammation and injury. The aim of this study was to investigate the effect of chronic exposure to waterpipe smoke on inflammatory markers and oxidative stress in the mouse lung.

METHOD

Using a whole-body exposure system, animals were exposed to waterpipe smoke for 6 weeks with a one-hour daily exposure for 5 days a week.

RESULTS

Exposure to waterpipe tobacco smoke induced the recruitment of inflammatory cells to the airway. Significant elevation in macrophages, lymphocytes and neutrophils was detected in the bronchoalveolar lavage fluid of exposed animals (P < 0.01). Furthermore, levels of catalase, glutathione peroxidase (GPx) and superoxide dismutase (SOD) in the lung homogenates were elevated (P < 0.05). Finally, waterpipe smoking altered the levels of a panel of inflammatory cytokines including TNFα, IL-1 β, IL-6, IL-10 and IL-12 biomarkers in the lung of exposed animals (P < 0.05).

CONCLUSION

These results support the notion that waterpipe tobacco smoking exerts harmful respiratory health effects.

Comparison of Cytotoxic Effect of Cigarette and Waterpipe Smoking on Human Buccal Mucosa

Background

The evidences on cytotoxic effect of cigarette and waterpipe smoking are very rare and controversial. The aim was to compare the cytotoxic effect of cigarette and waterpipe smoking on human buccal mucosa cells.

Methods

The study was case-control. Feulgen-stained samples of exfoliated buccal mucosa cells were evaluated. The cytology slides of 25 cigarette smoker, 25 waterpipe smoker, and 25 individuals in the never smoked were examined. The number of pyknosis, karyorrhexis, and karyolysis in 1000 cells/subject were counted. Exposing to cigarette and waterpipe smoke was considered by the number of pack × years.

Results

There were significant differences among the groups in terms of karyolysis and pyknosis while there was no significant difference among the cigarette smokers group and waterpipe smokers group in terms of karyorrhexis (P ≤ 0. 01). The cytotoxicity effect of cigarette smoking was not significantly correlated to time exposure (r = 0.099, P = 0.637). The cytotoxicity effect of waterpipe smoking was significantly correlated to time exposure (r = -370, P = 0.044).

Conclusions

The cytotoxic effect of cigarette and waterpipe smoking on buccal mucosa cells was significantly higher than nonsmokers. The effect of cigarette smoking on cellular death was higher than waterpipe. The cytotoxic effect of waterpipe smoking was dose dependent.

Micronucleus Assay in Exfoliated Buccal Epithelial Cells Using Liquid Based Cytology Preparations in Building Construction Workers

BACKGROUND AND OBJECTIVE

Cytogenetic damage in exfoliated buccal epithelial cells due to environmental and occupational exposure is often monitored by micronucleus (MN) assay using liquid based cytology (LBC) preparations. This study was performed to evaluate MN in exfoliated buccal epithelial cells of building construction workers using LBC preparations.

METHODS

LBC preparations of exfoliated buccal epithelial cells from 100 subjects [50 building construction workers (cases) and 50 administrative staffs (controls)] was evaluated by May-Grunwald Giemsa, Hematoxylin and Eosin and Papanicolaou stains. Student's t test was used for statistical analysis and a P value of <0.05 was considered as statistically significant.

RESULTS

The mean frequencies of MN for cases were significantly higher than controls regardless of staining methods used. There were statistically significant differences between smokers and non-smokers of the controls as well as duration of working exposure (<5 and >5 years) and smokers and non-smokers of cases (P=0.001). However, there were meaningful differences regarding mean frequencies of MN between smokers, non-smokers, those with alcohol consumption or not in cases and controls using various stains (P=0.001).

CONCLUSION

There was an increased risk of cytogenetic damage in building construction workers. However, evaluation of MN of exfoliated buccal epithelial cells in building construction workers serve as a minimally invasive biomarker for cytogenetic damage. LBC preparations can be applied for MN assay as it improves the quality of smears and cell morphology, decreases the confounding factors and reduces false positive results.

Increasing popularity of waterpipe tobacco smoking and electronic cigarette use: Implications for oral healthcare

Cigarette smoking increases the risk of developing several systemic conditions including cancer, cardiovascular and pulmonary diseases. Cigarette smoking is also detrimental to oral health as it increases the incidence and severity of oral cancer, periodontal diseases and peri-implantitis, as well as impacting negatively on the dental patients' response to therapy. Therefore, consideration of smoking behavior and recommendation of smoking cessation are important parts of dental treatment planning. However, cigarettes are no longer the most popular form of tobacco use among adolescents in the United States and globally. In recent years, tobacco smoking using a waterpipe ("hookah," "shisha") and use of electronic cigarettes (ECIGs) has increased significantly. Thus, dental clinicians likely will treat more patients who are waterpipe and/or ECIG users. Yet, the literature on the health effects of waterpipe and ECIGs use is sparse. Both waterpipe and ECIGs deliver the dependence-producing drug nicotine. Waterpipe tobacco smoking has been associated with periodontitis, dry socket, premalignant lesions, and oral and esophageal cancer. The health effects of long-term ECIG use are unknown. The purpose of this review is to inform healthcare professionals about waterpipes and ECIGs, highlight emerging evidence on the biological effects of these increasingly popular tobacco products, and introduce perspectives for dental patient management and future research.

Evaluation of Micronucleus in Exfoliated Buccal Epithelial Cells Using Liquid-based Cytology Preparation in Petrol Station Workers

Background:

Liquid-based cytology (LBC) can be used for the evaluation of micronucleus (MN) in exfoliated buccal epithelial cells of populations occupationally exposed to potentially carcinogenic agents.

Aim:

This study was undertaken to evaluate the frequency of MN of exfoliated buccal epithelial cells using LBC preparation in petrol station workers.

Materials and Methods:

Fifty petrol station workers (cases) and fifty hospital administrative staffs (controls) were recruited and evaluated for MN by May-Grunwald Giemsa, Hematoxylin and Eosin, and Papanicolaou stains using LBC preparation. Statistical analysis was performed with Student's t-test, and P < 0.05 was considered statistically significant.

Results:

Regardless of staining method used, the mean frequency of MN for cases was significantly higher than that of controls (P < 0.001).

Conclusion:

The present study concluded that petrol station workers are under risk of significant cytogenetic damage. The MN in exfoliated buccal epithelial cells found to be a useful biomarker of occupational exposure to genotoxic chemicals. LBC can be used for sample preparation to evaluate the frequency of MN in those who are occupationally exposed to potentially carcinogenic agents in view of overall improvement on sample preservation and visualization of cell morphology.

Determination of Genotoxic Effects of Hookah Smoking by Micronucleus and Chromosome Aberration Methods

BACKGROUND Use of a hookah (a type of water pipe) is a traditional way of smoking tobacco, particularly in the Middle East. In Turkey, its popularity has been growing in recent years, especially among young people. It is known that cigarette smoking has genotoxic effects and causes mutations, but no comprehensive study has been done on the genotoxic effects of hookah usage, particularly in Turkey. MATERIAL AND METHODS We collected peripheral blood/buccal smear samples from 30 subjects who did not smoke cigarettes but who regularly smoke a hookah an average of 2 times per week, and from 30 control subjects who had never smoked cigarettes or a hookah. Chromosome analyses were performed on the samples obtained from peripheral blood of each individual, 25 metaphase plaques were counted for each, and chromosome/chromatid breakage/gap parameters were evaluated. Micronucleus analysis was done on buccal smear samples and micronucleus/binucleus parameters were investigated by counting 2000 cells of each individual. RESULTS Chromosome breakage ratios were found to be 0.64±0.86 and 0.46±0.71 in the study and control groups, respectively, while chromatid breakage ratios were 0.53±0.83 and 0.53±0.71; fragment ratios were 0.82±1.24 and 0.21±0.49 (p<0.05); and gap ratios were 0.57±0.83 and 0.18±0.53 (p<0.05), respectively. Micronucleus ratio was 6.03±2.06 and 4.43±2.27 (p<0.05) in the study and control groups, respectively, and binucleus ratios were 8.53±3.23 and 12.15±5.18, respectively (p<0.05). CONCLUSIONS Results of our study reveal significant statistical differences between the individuals who smoked hookah and those who did not in terms of fragment, gap, micronucleus, and binucleus parameters, suggesting that smoking a hookah may cause genotoxic effects.

Nicotine exposure induces bronchial epithelial cell apoptosis and senescence via ROS mediated autophagy-impairment

Waterpipe smoking and e-cigarette vaping, the non-combustible sources of inhaled nicotine exposure are increasingly becoming popular and marketed as safer alternative to cigarette smoking. Hence, this study was designed to investigate the impact of inhaled nicotine exposure on disease causing COPD-emphysema mechanisms. For in vitro studies, human bronchial epithelial cells (Beas2b) were treated with waterpipe smoke extract (WPSE, 5%), nicotine (5mM), and/or cysteamine (250μM, an autophagy inducer and anti-oxidant drug), for 6hrs. We observed significantly (p<0.05) increased ubiquitinated protein-accumulation in the insoluble protein fractions of Beas2b cells treated with WPSE or nicotine that could be rescued by cysteamine treatment, suggesting aggresome-formation and autophagy-impairment. Moreover, our data also demonstrate that both WPSE and nicotine exposure significantly (p<0.05) elevates Ub-LC3β co-localization to aggresome-bodies while inducing Ub-p62 co-expression/accumulation, verifying autophagy-impairment. We also found that WPSE and nicotine exposure impacts Beas2b cell viability by significantly (p<0.05) inducing cellular apoptosis/senescence via ROS-activation, as it could be controlled by cysteamine, which is known to have an anti-oxidant property. For murine studies, C57BL/6 mice were administered with inhaled nicotine (intranasal, 500μg/mouse/day for 5 days), as an experimental model of non-combustible nicotine exposure. The inhaled nicotine exposure mediated oxidative-stress induces autophagy-impairment in the murine lungs as seen by significant (p<0.05, n=4) increase in the expression levels of nitrotyrosine protein-adduct (oxidative-stress marker, soluble-fraction) and Ub/p62/VCP (impaired-autophagy marker, insoluble-fraction). Overall, our data shows that nicotine, a common component of WPS, e-cigarette vapor and cigarette smoke, induces bronchial epithelial cell apoptosis and senescence via ROS mediated autophagy-impairment as a potential mechanism for COPD-emphysema pathogenesis.

Periodontal bone height of exclusive narghile smokers compared with exclusive cigarette smokers

OBJECTIVE

To compare the periodontal bone height (PBH) of exclusive narghile smokers (ENS) with that of exclusive cigarette smokers (ECS).

METHODS

Tunisian males aged 20-35 years who have been ENS for more than five narghile-years or ECS for more than five pack-years were recruited to participate in this comparative cross-sectional study. Information about oral health habits and tobacco consumption were gathered using a predetermined questionnaire. Plaque levels were recorded in four sites using the plaque index of Loe and Silness. The PBH was measured mesially and distally from digital panoramic radiographs of each tooth and expressed as a percentage of the root length. A PBH level ≤ 0.70 was applied as a cutoff reference value signifying bone loss. Student t-test and Chi(2) test were used to compare quantitative and qualitative data of both groups.

RESULTS

There were no significant differences between the ENS (n=60) and ECS (n=60) groups regarding age and the consumed quantities of tobacco (28 ± 4 vs. 27 ± 5 years, 7 ± 3 narghile-years vs. 8 ± 3 pack-years, respectively). Compared with the ECS group, the ENS group had a significantly higher plaque index (mean ± SD values were 1.54 ± 0.70 vs. 1.84 ± 0.73, respectively). However, the two groups had similar means of PBH (0.85 ± 0.03 vs. 0.86 ± 0.04) and tooth brushing frequencies (1.1 ± 0.8 vs. 0.9 ± 0.6 a day, respectively) and had similar bone loss frequencies (15% vs. 12%, respectively).

CONCLUSIONS

Both ENS and ECS exhibited the same PBH reduction, which means that both types of tobacco smoking are associated with periodontal bone loss.

Shisha smoking: An emerging trend in Southeast Asian nations

Shisha smoking, with origins in India and the Arab world, is today spreading rapidly into other parts of the world. One such region is Southeast Asia,where shisha bars are commonly seen around educational institutions. The general public remains unaware of the harmful effects of shisha smoking and many assume that shisha smoking does not involve tobacco. Shisha smoking is not adequately addressed in the current anti-tobacco policies by most governments of Southeast Asia. Only a few countries have already taken concrete measures of including shisha smoking in anti-tobacco policies. We highlight the emerging trend of shisha smoking in Southeast Asian nations, associated health effects, and the loopholes in the governmental policies that are being exploited by the vendors of shisha. While most research, taxation policies, and health education on tobacco-related products have focused on cigarettes, additional methods of tobacco delivery become more common.

Identification, characterization and antibiotic resistance of bacterial isolates obtained from waterpipe device hoses

The general lack of knowledge about the health effects of waterpipe smoking is among the reasons for its global spread. In this study, bacterial contamination of waterpipe hoses was investigated. Twenty hoses were collected from waterpipe cafés and screened for bacterial pathogens using standard culture and isolation techniques. Additionally, resistance of isolated bacteria to common antibiotics was determined by identifying the minimum inhibitory concentration (MIC) of each isolate. Forty eight bacterial isolates were detected. Isolates included both Gram-positive and Gram-negative pathogens from species that included Micrococcus (12), Corynebacterium (13) and Bacillus (9). In addition, some of the detected pathogens were found to be resistant to aztreonam (79%), cefixime (79%), norfloxacin, amoxicillin (47%), clarithromycin (46%) and enrofloxacin (38%). In conclusion, the hose of the waterpipe device is a good environment for the growth of bacterial pathogens, which can then be transmitted to users.

Health effects associated with waterpipe smoking

OBJECTIVE

It is widely held that waterpipe smoking (WPS) is not associated with health hazards. However, several studies have documented the uptake of several toxicants and carcinogens during WPS that is strongly associated with harmful health effects. This paper reviews the literature on the health effects of WPS.

DATA SOURCES

Three databases-PubMed, MEDLINE and EMBASE-were searched until August 2014 for the acute and long-term health effects of WPS using the terms 'waterpipe' and its synonyms (hookah, shisha, goza, narghileh, arghileh and hubble-bubble) in various spellings.

STUDY SELECTION

We included original clinical studies, case reports and systematic reviews and focused on clinical human studies. ∼10% of the identified studies met the selection criteria.

DATA EXTRACTION

Data were abstracted by all three authors and summarised into tables. Abstracted data included study type, results and methodological limitations and were analysed jointly by all three authors.

DATA SYNTHESIS

WPS acutely leads to increased heart rate, blood pressure, impaired pulmonary function and carbon monoxide intoxication. Chronic bronchitis, emphysema and coronary artery disease are serious complications of long-term use. Lung, gastric and oesophageal cancer are associated with WPS as well as periodontal disease, obstetrical complications, osteoporosis and mental health problems.

CONCLUSIONS

Contrary to the widely held misconception, WPS is associated with a variety of adverse short-term and long-term health effects that should reinforce the need for stronger regulation. In addition, this review highlights the limitations of the published work, which is mostly cross-sectional or retrospective. Prospective studies should be undertaken to assess the full spectrum of health effects of WPS, particularly in view of its growing popularity and attractiveness to youth.

Prevalence, social acceptance, and awareness of waterpipe smoking among dental university students: a cross sectional survey conducted in Jordan

BACKGROUND

Waterpipe tobacco smoking is increasing in popularity especially among young adults. This spread could be related to limited knowledge of the negative health effects of waterpipe smoking. In this study, prevalence, social acceptance, and awareness of waterpipe smoking were examined among dental university students.

METHODS

This is a cross-sectional survey study, where a self-administered questionnaire was completed by a sample of dental university students in Jordan.

RESULTS

Students (n=547) reported current tobacco use of 54.3% for males versus 11.1% for females (P<0.005). Among current smokers, 3.5% used only cigarettes (22.0% males, 2.3% females), 12.6% used only waterpipe (36.6% males, 88.6% females), and 6.9% used both (41.5% males, 9.1% females). Approximately, 70% of males and 42.5% of females who used waterpipe reported smoking mostly at a café. Nearly half of the females reported that they smoke at home in the presence of parents. Among participants, 33.3% of males and 62.5% of females reported indifferent parents' reaction regarding their waterpipe smoking. Approximately one third of students agreed with the statement that waterpipe smoking is less harmful to oral health than cigarette smoking. About 50-70% of students agreed that waterpipe smoking causes halitosis, delays wound healing time, is associated with dental implant failure, and increases the risk of dental decay.

CONCLUSIONS

In this sample, waterpipe tobacco smoking was more common than cigarette smoking among dental students, especially females. This could be an implication of social acceptance of waterpipe leading to its predominance, and thus, the gradual replacement of cigarette smoking with waterpipe smoking. Additionally, dental students' awareness about the harms of waterpipe is not optimal, and steps are needed to ensure providing such knowledge to students.

Non-cigarette tobacco and the lung

Cigarette smoking is known to cause a wide range of damaging health outcomes; however, the effects of non-cigarette tobacco products are either unknown or perceived as less harmful than cigarettes. Smokeless tobacco, cigar smoking, and waterpipe smoking have increased in usage over the past few decades. Some experts believe that their use is reaching epidemic proportions. Factors such as a perception of harm reduction, targeted advertising, and unrecognized addiction may drive the increased consumption of non-cigarette tobacco products. In particular, the need for social acceptance, enjoyment of communal smoking activities, and exotic nature of waterpipe smoking fuels, in part, its popularity. The public is looking for "safer" alternatives to smoking cigarettes, and some groups advertise products such as smokeless tobacco and electronic cigarettes as the alternatives they seek. Though it is clear that cigar and waterpipe tobacco smoking are probably as dangerous to health as cigarette smoking, there is an opinion among users that the health risks are less compared to cigarette smoking. This is particularly true in younger age groups. In the cases of smokeless tobacco and electronic cigarettes, the risks to health are less clear and there may be evidence of a harm reduction compared to cigarettes. In this article, we discuss commonly used forms of non-cigarette tobacco products, their impacts on lung health, and relevant controversies surrounding their use.

Young adult waterpipe smokers: Smoking behaviors and associated subjective and physiological effects

INTRODUCTION

The purpose of this pilot study was to investigate smoking behaviors and subjective and physiological effects of nicotine on young adult occasional waterpipe smokers.

METHODS

This study utilized a repeated-measures design that included one repeated factor for condition (nicotine and non-nicotine). For each participant, the sequencing of the repeated factor was assigned using random allocation. The two nicotine conditions were nicotine (0.75 g) and non-nicotine (0 g placebo) tobacco. Over the course of two weeks, twenty-two participants completed subjective (Acute Subjective Effects of Nicotine) and physiological (blood pressure, heart rate, and CO level) measures. Additional measures (QSU and MNWS-R) were used to assess for withdrawal symptoms.

SAMPLE

The participants (n=22) were young adults (23 ± 3.1years); 71% smoked waterpipe once a month in the past year and 29% smoked waterpipe 1-2 times per week. In addition, 60% reported sharing their waterpipe with friends while smoking. None of the participants reported using any other forms of tobacco products.

RESULTS

Under the nicotine condition, participants tended to smoke longer (i.e. smoking duration, p=0.004), take more puffs (p=0.03), take shorter puffs (p=0.03), and inhale less volume with each puff (p=0.02). The repeated measures analysis of the factor headrush revealed an effect of the nicotine condition (F=9.69, p<0.001, partial η(2)=0.31) and time (F=8.17, p=0.02, partial η(2)=0.30). Heart rate increased significantly across the nicotine condition (F=7.92, p=0.01, partial η(2)=0.31) and over time (F=12.64, p=0.01, partial η(2)=0.41).

CONCLUSIONS

This study demonstrates how differences between nicotine and non-nicotine waterpipe smoking are associated with changes in smoking behaviors, experiencing a headrush and an increase in heart rate.

Micronucleus evaluation of exfoliated buccal epithelial cells using liquid-based cytology preparation

OBJECTIVE

Micronuclei (MN) are biomarkers that can be applied to buccal epithelial cells to assess populations occupationally exposed to potentially carcinogenic agents. Liquid-based cytology (LBC) is a way to improve and refine the results obtained by this test.

STUDY DESIGN

Exfoliated buccal cells were collected from 40 subjects (20 construction workers from the Barretos Cancer Hospital and 20 administrative staff from the same institution). LBC and three stains (Feulgen/fast green, Papanicolaou and Giemsa) were used to prepare the slides. Student's t test was applied for statistical comparisons of the data. A p value of <0.05 was considered statistically significant.

RESULTS

Regardless of the stain employed, the frequency of MN was greater in the case group (Feulgen/fast green: 5.15; Papanicolaou: 29; Giemsa: 26) than in the control group (Feulgen/fast green: 2.30; Papanicolaou: 17; Giemsa: 15).

CONCLUSIONS

Using LBC to prepare slides and evaluate the frequency of MN potentially serves as a screening option for more comprehensive studies of cancer risk among populations occupationally exposed to potentially carcinogenic agents. In addition, the residual fluid enables the preparation of slides for DNA-specific stains that can be compared to those with Papanicolaou stain.

Mixed methods pilot study of sharing behaviors among waterpipe smokers of rural Lao PDR: implications for infectious disease transmission

To date, the sharing behaviors associated with the homemade tobacco waterpipe used in rural areas of the Western Pacific Region have not been studied. Evidence from studies of manufactured waterpipes raises the possibility of infectious disease transmission due to waterpipe sharing. The objective of our pilot study in rural Lao People’s Democratic Republic (PDR) was to identify and measure the prevalence of waterpipe sharing behaviors. We first conducted ethnographic studies to investigate waterpipe-smoking behaviors. These findings were then used to develop an interviewer-administered household survey that was used in a sampling of waterpipe smokers from three villages of the Luang Namtha province of Lao PDR (n = 43). Sampled waterpipe smokers were predominantly male (90.7%), older (mean age 49, SD 13.79), married (95.4%), farmers (78.6%), and had completed no primary education. Pipes were primarily made from bamboo (92.9%). Almost all (97.6%) smokers were willing to share their pipe with others. At the last time they smoked, smokers shared a pipe with at least one other person (1.2 ± 0.5 persons). During the past week, they had shared a pipe with five other persons (5.2 ± 3.8 persons). The high prevalence of sharing behaviors among waterpipe smokers in rural Southeast Asia raises the possibility that this behavior provides important and unmeasured social network pathways for the transmission of infectious agents.

The waterpipe: an emerging global risk for cancer

Tobacco smoking continues to be the leading preventable cause of morbidity and mortality worldwide. Each year more than 5 million smokers die prematurely because of their habit wreaking havoc on the welfare of families and communities worldwide. While cigarettes remain the main tobacco killer worldwide, for many youth tobacco use and addiction is maintained by means other than cigarettes. In particular, over the past decade, waterpipe smoking (a.k.a. hookah, shisha, narghile) has become increasingly popular among youth in the Middle East, and is rapidly spreading globally. Available evidence suggests that waterpipe smoking is associated with many of the known risks of tobacco smoking, particularly cancer. Despite these worrisome signs, policies and interventions to address this emerging public health problem have been lagging behind. In this short review I discuss briefly the evidence generated mostly in the past decade about the global spread of waterpipe smoking and its cancer risk potential.

Assessment of DNA damage using chromosomal aberrations assay in lymphocytes of waterpipe smokers

OBJECTIVES

The aim of this study was to investigate the genotoxicity of waterpipe smoking in the lymphocytes of waterpipe smokers using chromosomal aberrations (CAs) assay.

MATERIALS AND METHODS

Fifty waterpipe smokers and 18 healthy non-smokers volunteered to participate in the study. Additionally, 18 heavy cigarette smokers were recruited for comparison. Chromosomal aberrations (CAs) assay was used to evaluate DNA damage in the lymphocytes.

RESULTS

The results showed that similarly to cigarette smoking, waterpipe smoking significantly increased the frequencies of CAs (p < 0.01). In addition, the frequencies of CAs increased with more waterpipe use.

CONCLUSIONS

Waterpipe smoking causes DNA damage to lymphocytes and the damage increases with more waterpipe use.

In vitro cytotoxicity and mutagenicity of mainstream waterpipe smoke and its functional consequences on alveolar type II derived cells

INTRODUCTION

While waterpipe tobacco smoking has become a global phenomenon, its potential health consequences are poorly understood. In this manuscript, we report the in vitro mutagenicity of waterpipe smoke condensate (WSC), the alteration in cellular parameters of lung alveolar cells in response to WSC exposure and discuss the implication of cellular responses in the pathophysiology of chronic obstructive pulmonary disease (COPD).

METHODS

The mainstream WSC was generated using a standard laboratory machine protocol. We assessed its mutagenicity using Ames test. In addition, we studied the effect of WSC on the proliferation and cell cycle of alveolar type II cells and vascular endothelial cells. We also assessed the effect of WSC on the expression of genes involved in cell cycle arrest and inflammation.

RESULTS

Within the range of tested doses, WSC did not elicit sufficient response to be considered mutagenic in any of the strains tested (TA98, TA100, TA102, and TA97a) but were found to be toxic for strains TA97a and TA102 at the highest tested doses. However, WSC induced cell cycle arrest and cellular senescence mediated by the p53-p21 pathway. Also our study indicated that WSC induced an increase in the transcriptional expression of matrix metalloproteinases, MMP-2 and MMP-9 and an immune response regulator, Toll Like Receptor-4.

CONCLUSION

The data reported here represent the first in vitro demonstration of the effect of waterpipe smoke on cellular parameters providing evidence of the potential involvement of WPS in the pathogenesis of COPD through impairing cellular growth and inducing inflammation.

Assessment of DNA damage using chromosomal aberrations assay in lymphocytes of waterpipe smokers

OBJECTIVES

The aim of this study was to investigate the genotoxicity of waterpipe smoking in the lymphocytes of waterpipe smokers using chromosomal aberrations (CAs) assay.

MATERIALS AND METHODS

Fifty waterpipe smokers and 18 healthy non-smokers volunteered to participate in the study. Additionally, 18 heavy cigarette smokers were recruited for comparison. Chromosomal aberrations (CAs) assay was used to evaluate DNA damage in the lymphocytes.

RESULTS

The results showed that similarly to cigarette smoking, waterpipe smoking significantly increased the frequencies of CAs (p < 0.01). In addition, the frequencies of CAs increased with more waterpipe use.

CONCLUSIONS

Waterpipe smoking causes DNA damage to lymphocytes and the damage increases with more waterpipe use.

Tobacco-specific nitrosamine exposures in smokers and nonsmokers exposed to cigarette or waterpipe tobacco smoke

INTRODUCTION

The causal relationship between tobacco smoking and a variety of cancers is attributable to the carcinogens that smokers inhale, including tobacco-specific nitrosamines (TSNAs). We aimed to assess the exposure to TSNAs in waterpipe smokers (WPS), cigarette smokers (CS), and nonsmoking females exposed to tobacco smoke.

METHODS

We measured 2 metabolites, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and its glucuronides (NNAl-Gluc) in the urine of males who were either current CS or WPS, and their wives exposed to either cigarette or waterpipe smoke in a sample of 46 subjects from rural Egypt.

RESULTS

Of the 24 current male smokers, 54.2% were exclusive CS and 45.8% were exclusive WPS. Among wives, 59.1% reported exposure to cigarette smoke and 40.9% to waterpipe smoke. The geometric mean of urinary NNAL was 0.19 ± 0.60 pmol/ml urine (range 0.005-2.58) in the total sample. Significantly higher levels of NNAL were observed among male smokers of either cigarettes or waterpipe (0.89 ± 0.53 pmol/ml, range 0.78-2.58 in CS and 0.21-1.71 in WPS) compared with nonsmoking wives (0.04 ± 0.18 pmol/ml, range 0.01-0.60 in CS wives, 0.05-0.23 in WPS wives, p = .000). Among males, CS had significantly higher levels of NNAL compared with WPS (1.22 vs. 0.62; p = .007). However, no significant difference was detected in NNAL levels between wives exposed to cigarette smoke or waterpipe smoke.

CONCLUSIONS

Cigarette smokers levels of NNAL were higher than WPS levels in males. Exposure to tobacco smoke was evident in wives of both CS and WPS. Among WPS, NNAL tended to increase with increasing numbers of hagars smoked/day.