Metabolites of a tobacco-specific lung carcinogen in nonsmoking women exposed to environmental tobacco smoke

Porous Polymers Containing Metallocalix[4]arene for the Extraction of Tobacco-Specific Nitrosamines

We designed porous polymers with a tungsten-calix[4]arene imido complex as the nitrosamine receptor for the efficient extraction of tobacco-specific nitrosamines (TSNAs) from water. The interaction between the metallocalix[4]arene and the TSNA, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (nicotine-derived nitrosamine ketone, NNK) was investigated. We found that the incorporation of the nitrosamine receptor into porous polymers increased their selectivity toward NNK over nicotine. The polymer with an optimal ratio of calixarene-containing and porosity-inducing building blocks showed a high maximum adsorption capacity of up to 203 mg/g toward NNK under sonication, which was among the highest values reported. The adsorbed NNK could be removed from the polymer by soaking it in acetonitrile, enabling the adsorbent to be reused. A similar extraction efficiency to that under sonication could be achieved using the polymer-coated magnetic particles under stirring. We also proved that the material could efficiently extract TSNAs from real tobacco extract. This work not only provides an efficient material for the extraction of TSNAs but also offers a design strategy for efficient adsorbents.

Assessment of passive human exposure to tobacco smoke by environmental and biological monitoring in different public places in Wuhan, central China

Passive exposure to tobacco smoke is a global public health problem, while there are few data on public place monitoring and general population exposure assessment in central China. This study aimed to examine the levels of airborne nicotine (n = 256) in ten kinds of different public places in Wuhan, central China, and assess short-term and long-term smoke exposure in 340 non-smokers aged 18-67 who worked in these public places using tobacco biomarkers [i.e., cotinine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), respectively]. The highest median concentration of airborne nicotine (17.0 μg/m³) was observed in internet cafes, approximately 304-fold of the lowest value found in nurseries (55.9 ng/m³). Among the other studied public places, restaurants had the highest median concentrations (ng/m³) of airborne nicotine (3,120), followed by subway stations (810), hotels (624), government officess (286), middle schools (269), health institutions (268), public institutions (190), and primary schools (140). Urinary cotinine and NNAL were found in almost all the participants, and the highest concentrations were found in non-smokers from the internet cafes [specific gravity (SG)-corrected urinary median concentrations: 23.1 ng/mL, geometric mean (GM): 24.1 ng/mL, range: 0.62-1679 ng/mL] for cotinine and 104 pg/mL (GM: 97.6 pg/mL, range: 32.3-236 pg/mL) for NNAL, respectively]. Urinary cotinine concentrations in male non-smokers (median: 2.02 ng/mL) were significantly higher than those in female non-smokers (1.44) (P < 0.01). Participants aged 18-27 were detected with the highest urinary cotinine and NNAL concentrations. Urinary cotinine and NNAL concentrations were significantly correlated with daily and monthly working hours, respectively. Besides, a positive correlation was observed between log-transformed urinary concentrations of cotinine and NNAL (r = 0.32, P < 0.001). This is the first time to report matched data on airborne nicotine and urinary cotinine/NNAL among employees in different public places. This study demonstrated ubiquitous exposure to environmental tobacco smoke in the studied public places.

Metabolism and DNA Adduct Formation of Tobacco-Specific N-Nitrosamines

The tobacco-specific N-nitrosamines 4-(N-nitrosomethylamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN) always occur together and exclusively in tobacco products or in environments contaminated by tobacco smoke. They have been classified as "carcinogenic to humans" by the International Agency for Research on Cancer. In 1998, we published a review of the biochemistry, biology and carcinogenicity of tobacco-specific nitrosamines. Over the past 20 years, considerable progress has been made in our understanding of the mechanisms of metabolism and DNA adduct formation by these two important carcinogens, along with progress on their carcinogenicity and mutagenicity. In this review, we aim to provide an update on the carcinogenicity and mechanisms of the metabolism and DNA interactions of NNK and NNN.

Environmental Tobacco Smoke in Occupational Settings: Effect and Susceptibility Biomarkers in Workers From Lisbon Restaurants and Bars

Environmental tobacco smoke (ETS) has been recognized as a major health hazard by environmental and public health authorities worldwide. In Portugal, smoke-free laws are in force for some years, banning smoking in most indoor public spaces. However, in hospitality venues such as restaurants and bars, owners can still choose between a total smoke-free policy or a partial smoking restriction with designated smoking areas, if adequate reinforced ventilation systems are implemented. Despite that, a previous study showed that workers remained continuously exposed to higher ETS pollution in Lisbon restaurants and bars where smoking was still allowed, comparatively to total smoke-free venues. This was assessed by measurements of indoor PM2.5 and urinary cotinine, a biomarkers of tobacco smoke exposure, demonstrating that partial smoking restrictions do not effectively protect workers from ETS. The aim of the present work was to characterize effect and susceptibility biomarkers in non-smokers from those hospitality venues occupationally exposed to ETS comparatively to non-exposed ones. A group of smokers was also included for comparison. The sister chromatid exchange (SCE), micronucleus (MN) and comet assays in whole peripheral blood lymphocytes (PBLs) and the micronucleus assay in exfoliated buccal cells, were used as biomarkers of genotoxicity. Furthermore, a comet assay after ex vivo challenge of leukocytes with an alkylating agent, ethyl methanesulfonate (EMS), was used to analyze the repair capacity of those cells. Genetic polymorphisms in genes associated with metabolism and DNA repair were also included. The results showed no clear association between occupational exposure to ETS and the induction of genotoxicity. Interestingly, the leukocytes from non-smoking ETS-exposed individuals displayed lower DNA damage levels in response to the ex vivo EMS challenge, in comparison to those from non-exposed workers, suggesting a possible adaptive response. The contribution of individual susceptibility to the effect biomarkers studied was unclear, deserving further investigation.

Biochemical Verification of Tobacco Use and Abstinence: 2019 Update

BACKGROUND

The changing prevalence and patterns of tobacco use, the advent of novel nicotine delivery devices, and the development of new biomarkers prompted an update of the 2002 Society for Research on Nicotine and Tobacco (SRNT) report on whether and how to apply biomarker verification for tobacco use and abstinence.

METHODS

The SRNT Treatment Research Network convened a group of investigators with expertise in tobacco biomarkers to update the recommendations of the 2002 SNRT Biochemical Verification Report.

RESULTS

Biochemical verification of tobacco use and abstinence increases scientific rigor and is recommended in clinical trials of smoking cessation, when feasible. Sources, appropriate biospecimens, cutpoints, time of detection windows and analytic methods for carbon monoxide, cotinine (including over the counter tests), total nicotine equivalents, minor tobacco alkaloids, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol are reviewed, as well as biochemical approaches to distinguishing cigarette smoking from use of electronic nicotine delivery devices (ENDS).

CONCLUSIONS

Recommendations are provided for whether and how to use biochemical verification of tobacco use and abstinence. Guidelines are provided on which biomarkers to use, which biospecimens to use, optimal cutpoints, time windows to detection, and methodology for biochemical verifications. Use of combinations of biomarkers is recommended for assessment of ENDS use.

IMPLICATIONS

Biochemical verification increases scientific rigor, but there are drawbacks that need to be assessed to determine whether the benefits of biochemical verification outweigh the costs, including the cost of the assays, the feasibility of sample collection, the ability to draw clear conclusions based on the duration of abstinence, and the variability of the assay within the study population. This paper provides updated recommendations from the 2002 SRNT report on whether and how to use biochemical markers in determining tobacco use and abstinence.

Applying Tobacco, Environmental, and Dietary-Related Biomarkers to Understand Cancer Etiology and Evaluate Prevention Strategies

Many human cancers are caused by environmental and lifestyle factors. Biomarkers of exposure and risk developed by our team have provided critical data on internal exposure to toxic and genotoxic chemicals and their connection to cancer in humans. This review highlights our research using biomarkers to identify key factors influencing cancer risk as well as their application to assess the effectiveness of exposure intervention and chemoprevention protocols. The use of these biomarkers to understand individual susceptibility to the harmful effects of tobacco products is a powerful example of the value of this type of research and has provided key data confirming the link between tobacco smoke exposure and cancer risk. Furthermore, this information has led to policy changes that have reduced tobacco use and consequently, the tobacco-related cancer burden. Recent technological advances in mass spectrometry led to the ability to detect DNA damage in human tissues as well as the development of adductomic approaches. These new methods allowed for the detection of DNA adducts in tissues from patients with cancer, providing key evidence that exposure to carcinogens leads to DNA damage in the target tissue. These advances will provide valuable insights into the etiologic causes of cancer that are not tobacco-related.See all articles in this CEBP Focus section, "Environmental Carcinogenesis: Pathways to Prevention."

Smoking Cessation and the Risk of Bladder Cancer among Postmenopausal Women

Smoking is the strongest established risk factor for bladder cancer. Former smokers have a lower risk of bladder cancer compared with current smokers, but findings on the dose-response relationship between years after quitting and the risk of bladder cancer are inconsistent. A total of 143,279 postmenopausal women from the Women's Health Initiative Study were included. Cox proportional hazards regression models were applied for estimating age- and multivariable-adjusted HRs and their 95% confidence intervals (CI). There were 870 bladder cancer cases identified over an average of 14.8 years of follow-up. After adjusting for pack-years of smoking, bladder cancer risk among former smokers declined by 25% within the first 10 years of cessation and continued to decrease as cessation time increased but remained higher than never smokers after 30 years of quitting (HR, 1.92; 95% CI, 1.43-2.58). Smokers who quit smoking had a lower risk of bladder cancer compared with current smokers (HR, 0.61; 95% CI, 0.40-0.94). We conclude that among postmenopausal women, there is a significant reduction in the risk of bladder cancer after quitting smoking. In addition to primary prevention, smoking cessation is critical to prevent the incidence of bladder cancer in older women.

Counseling alone or in combination with nicotine replacement therapy for treatment of black non-daily smokers: a randomized trial

BACKGROUND AND AIMS

One-third of US tobacco users are non-daily smokers (NDS). Black NDS have strikingly high levels of nicotine and carcinogen exposure. No smoking cessation studies have been conducted with this high-risk group. This study compared the effectiveness in black NDS of smoking cessation counseling alone or in combination with the participant's choice of nicotine replacement therapy.

DESIGN

Two-arm parallel-group individually randomized clinical trial (allocation ratio of 2 : 1 intervention to control) SETTING: Academic medical and federally qualified health centers in three US cities.

PARTICIPANTS

Non-Hispanic black adult NDS receiving counseling with nicotine replacement therapy (C + NRT, n = 185) or counseling alone (C, n = 93).

INTERVENTIONS

Twelve weeks of in-person and telephone smoking cessation counseling in combination with nicotine replacement therapy (NRT; C + NRT) or counseling alone (C). All participants received five sessions of counseling; those randomized to C + NRT received their choice of nicotine gum, patch and/or lozenge after a 9-day product trial period. The target quit day was set at 2 weeks post-baseline for both groups.

MEASUREMENTS

Primary outcome was biochemically verified 30-day abstinence at week 12. Secondary outcomes were change in nicotine and carcinogen exposure [4-(methynitrosamino)-1-(3) pyridyle-1-butanol; NNAL] and tobacco consumption patterns.

FINDINGS

Abstinence was 11.4% in C + NRT and 8.6% in C [odds ratio (OR) = 1.4, 95% confidence interval (CI) = 0.6, 3.2, P = 0.48]. Both groups experienced significant reduction in NNAL (C + NRT: 53% reduction, C: 50% reduction, within-group P < 0.0001) but non-significant changes in cotinine (P = 0.69). C + NRT reported more days abstinent (P < 0.001) and fewer total cigarettes (P = 0.002) compared with C. There was no evidence of compensation with other tobacco products.

CONCLUSIONS

Among black non-daily smokers in the United States, there was no difference in abstinence between nicotine replacement therapy (NRT) and counseling alone. NRT led to greater increase in days abstinent and reduction in cigarettes, with no evidence of compensation from other sources of nicotine.

Assessment of tobacco specific nitrosamines (TSNAs) in oral fluid as biomarkers of cancer risk: A population-based study

BACKGROUND

Smoke-free laws are expected to reduce smoking habits and exposure to secondhand smoke. The objective of this study was the measurement of tobacco specific carcinogens (TSNAs) in oral fluid to assess the most suitable biomarker of cancer risk associated with tobacco smoke.

METHODS

TSNAs, N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), as well as nicotine and cotinine were measured in oral fluid samples from 166 smokers and 532 non-smokers of the adult population of Barcelona, Spain. A simple method with an alkaline single liquid-liquid extraction with dichloromethane/isopropanol was used and lower limits of quantification for cotinine, NNN, NNK and NNAL were set at 0.10ng/mL, 1.0, 2.0 and 0.50pg/mL respectively. The NNN/cotinine ratio was also calculated.

RESULTS

NNN was the most abundant TSNA present in oral fluid with a significant difference between smokers and non-smokers (mean concentrations of 118 and 5.3pg/mL, respectively, p<0.001). NNK and NNAL were detectable in fewer samples. NNN and cotinine concentrations had a moderate correlation within both groups (Spearman's rank correlation coefficient of 0.312, p<0.001 in smokers and 0.279, p=0.022 in non-smokers). NNN/cotinine ratio was significantly higher (p<0.001) in non-smokers than in smokers, in line with equivalent findings for the NNAL/cotinine ratio in urine.

CONCLUSIONS

TSNAs are detectable in oral fluid of smokers and non-smokers. NNN is the most abundant, in line with its association with esophageal and oral cavity cancers. The NNN/cotinine ratio confirms the relative NNN increase in second hand smoke. Findings provide a new oral fluid biomarker of cancer risk associated with exposure to tobacco smoke.

Evaluation of tobacco specific nitrosamines exposure by quantification of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in human hair of non-smokers

Chronic exposure to specific carcinogens present in secondhand smoke has been associated with different types of cancers. Hair is an ideal matrix to develop a proper biomarker as it absorbs substances in circulation and allows measuring their average concentration over long periods of time. A method was developed for the simultaneous quantification of nicotine, cotinine, NNN, NNK and NNAL in 20 mg human hair samples. Concentrations were significantly different depending on the declared exposure. This study shows for the first time that NNK is present in hair samples from non-smokers in concentrations much higher than any other tobacco specific nitrosamine. NNN could also be detected in samples from the most exposed non-smokers while, as previously reported, NNAL was undetectable. NNK correlates well with nicotine and cotinine (rsp = 0.774 and rsp = 0.792 respectively, p < 0.001 in both cases). However, NNN concentrations did not correlate with any of the other analytes. Ratios between NNK and nicotine show variability with different concentrations of NNK present in samples with similar nicotine values. NNK has proven to be the best marker of tobacco specific nitrosamines in hair. Monitoring NNK may provide a good estimation of cancer risk associated with exposure to secondhand smoke.

[Surgical treatment of patients with oral leukoplakia]

The aim of the study was to elaborate lingual nerve sparing procedure of submandibular gland duct stones extraction. The study involved 43 patients with syalolithiasis treated in Oral Surgery Unit of Central Research Institute of Dentistry and Maxillofacial Surgery in 2013-2015. It was shown that to prevent lingual nerve and artery injury submandibular salivary gland duct should be dissected to the level of obstruction thus allowing adequate visualization of anatomical correlations especially when removing stones from the distal part of the duct.

Simple high-throughput analytical method using ultra-performance liquid chromatography coupled with tandem mass spectrometry to quantify total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol in urine

BACKGROUND

Since the urinary concentration of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is a reliable biomarker of exposure to tobacco smoke, we developed a relatively simple high-throughput chromatographic method to quantify total urinary NNAL concentrations in the general population.

METHODS

The high-throughput analytical method was developed using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) to identify and quantify total urinary NNAL concentrations in 10 non-smokers and 15 otherwise healthy smokers.

RESULTS

Loss of nitric oxide at m/z 30 was found to be the predominant mass transitioned, and therefore was used as the SIM transition to quantify both NNAL and NNAL-methyl-d3 in urine. The analytical method did not require sample derivatization. Standard curves for total NNAL concentrations were linear between 20 and 1500 pg/mL, with coefficients of determination >0.95. Precision and accuracy ranged from 2.2% to 8.6% (CV) and from -5.6% to 10.9% (percent error), respectively. The lowest limit of quantification was 6.7 pg/mL, and 2.0 pg/mL the lowest limit of detection (LLOD). Total urinary NNAL concentrations in non-smoker subjects were <LLOD, whereas in smokers varied between <LLOD to 112.1 pg/mL.

CONCLUSIONS

An UPLC-MS/MS analytical method to quantify total urinary NNAL concentrations in smokers that does not require sample derivatization is presented herein. The method could be useful in clarifying the toxicities associated with human exposure to cigarette smoking. However, quantification might be adversely affected by co-eluting interfering compounds or selective ion suppression or enhancement as a result of having only one ion transition to monitor NNAL and NNAL-methyl-d3 in urine.

Levels of tobacco-specific metabolites among non-smoking lung cancer cases at diagnosis: case-control findings

BACKGROUND

Environmental tobacco smoking (ETS) significantly contributes to morbidity and mortality and is a known risk factor for lung cancer development in lifelong nonsmokers. The metabolite 4-(methylnitrosamino)- 1-(3-pyridyl)-1-butanol (NNAL) and its glucuronides (NNAL-Glucs) have now emerged as leading biomarkers for the study of carcinogen exposure in non-smokers exposed to ETS.

MATERIALS AND METHODS

We carried out our study on NNAL in the urine of non-smokers exposed to ETS and the association between ETS and lung cancer. Subjects were enrolled from 2008-2010. NNAL was analyzed for 74 non-smoking lung cancer and 85 healthy controls. The main objective of this study was to provide an estimate of the risk of lung cancer from exposure to ETS in the Korean population.

RESULTS

The mean NNAL concentration in urine was significantly lower in non-smoking patient groups (n=74) than in control groups (n=85) (4.7±15.0 pg/mg, 6.5 ± 17.9 pg/mg, respectively, Mann-Whitney U test, p<0.001).

CONCLUSIONS

The urine NNAL of non-smoking patients with lung cancer was not elevated with regard to the non-smoking control group. This may be due to life-style changes after diagnosis. A prospective study will be needed to evaluate the association of NNAL and non-smoking lung cancer.

Nicotine and carcinogen exposure after water pipe smoking in hookah bars

BACKGROUND

Water pipe tobacco smoking is spreading globally and is increasingly becoming popular in the United States, particularly among young people. Although many perceive water pipe smoking to be relatively safe, clinical experimental studies indicate significant exposures to tobacco smoke carcinogens following water pipe use. We investigated biomarkers of nicotine intake and carcinogen exposure from water pipe smoking in the naturalistic setting of hookah bars.

METHODS

Fifty-five experienced water pipe users were studied before and after smoking water pipe in their customary way in a hookah bar. Urine samples were analyzed for nicotine, cotinine, the tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), and mercapturic acid metabolites of volatile organic compounds (VOC).

RESULTS

We found an average 73-fold increase in nicotine, 4-fold increase in cotinine, 2-fold increase in NNAL, and 14% to 91% increase in VOC mercapturic acid metabolites immediately following water pipe smoking. We saw moderate to high correlations between changes in tobacco-specific biomarkers (nicotine, cotinine, and NNAL) and several mercapturic acid metabolites of VOCs.

CONCLUSION

Water pipe smoking in a hookah bar is associated with significant nicotine intake and carcinogen exposure.

IMPACT

Given the significant intake of nicotine and carcinogens, chronic water pipe use could place users at increased risk of cancer and other chronic diseases. Cancer Epidemiol Biomarkers Prev; 23(6); 1055-66. ©2014 AACR.

Biomarkers of tobacco smoke exposure and asthma severity in adults

BACKGROUND

Tobacco biomarkers including serum cotinine and urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) have been used in research settings.

PURPOSE

The goal of the study was to examine the association of cotinine and NNAL with asthma outcomes in the U.S. adult population.

METHODS

A cross-sectional design was used, using data from the National Health and Nutrition Examination Survey, 2007-2008, with participants aged >20 years with self-reported asthma (N=456). Past-year asthma exacerbations and emergency room/urgent care visits for asthma were examined. Analyses were conducted in 2013.

RESULTS

Among adult asthmatics, 50.3% reported a past-year asthma attack (61.8% smokers, 46.6% nonsmokers, p=0.029). Among these, 24.7% reported a past-year emergency/urgent visit for asthma (34.7% smokers, 20.1% nonsmokers, p=0.034). Median concentrations of cotinine and creatinine-adjusted NNAL (NNAL/Cr) were significantly higher in those with a past-year asthma attack (0.43 ng/mL and 7.28 pg/mL) than in those without (0.06 ng/mL and 2.26 pg/mL), and highest in those with past-year emergency/urgent visits (0.93 ng/mL and 28.14 pg/mL). Among nonsmokers, increasing levels of log cotinine or log NNAL/Cr, adjusted for demographics, were significantly associated with past-year asthma exacerbation (log cotinine OR=1.46 [95% CI=1.1, 1.92]; log NNAL/Cr OR=1.42 [95% CI=1.07, 1.88]) and past-year emergency/urgent visit (log cotinine OR=1.95 [95% CI=1.32, 2.88]; log NNAL/Cr OR=1.58 [95% CI=1.23, 2.02]). Among smokers, increasing biomarker levels were not significantly associated with either outcome.

CONCLUSIONS

In a population-based cross-sectional analysis, increased cotinine and NNAL were found to be associated with asthma exacerbation and healthcare use in nonsmokers with asthma. If these findings are confirmed in prospective studies, these biomarkers might be candidates for clinical indicators of risk of asthma.

Secondhand tobacco smoke exposure in open and semi-open settings: a systematic review

BACKGROUND

Some countries have recently extended smoke-free policies to particular outdoor settings; however, there is controversy regarding whether this is scientifically and ethically justifiable.

OBJECTIVES

The objective of the present study was to review research on secondhand smoke (SHS) exposure in outdoor settings.

DATA SOURCES

We conducted different searches in PubMed for the period prior to September 2012. We checked the references of the identified papers, and conducted a similar search in Google Scholar.

STUDY SELECTION

Our search terms included combinations of "secondhand smoke," "environmental tobacco smoke," "passive smoking" OR "tobacco smoke pollution" AND "outdoors" AND "PM" (particulate matter), "PM(2.5)" (PM with diameter ≤ 2.5 µm), "respirable suspended particles," "particulate matter," "nicotine," "CO" (carbon monoxide), "cotinine," "marker," "biomarker" OR "airborne marker." In total, 18 articles and reports met the inclusion criteria.

RESULTS

Almost all studies used PM(2.5) concentration as an SHS marker. Mean PM(2.5) concentrations reported for outdoor smoking areas when smokers were present ranged from 8.32 to 124 µg/m(3) at hospitality venues, and 4.60 to 17.80 µg/m(3) at other locations. Mean PM(2.5) concentrations in smoke-free indoor settings near outdoor smoking areas ranged from 4 to 120.51 µg/m(3). SHS levels increased when smokers were present, and outdoor and indoor SHS levels were related. Most studies reported a positive association between SHS measures and smoker density, enclosure of outdoor locations, wind conditions, and proximity to smokers.

CONCLUSIONS

The available evidence indicates high SHS levels at some outdoor smoking areas and at adjacent smoke-free indoor areas. Further research and standardization of methodology is needed to determine whether smoke-free legislation should be extended to outdoor settings.

Assessing secondhand smoke using biological markers

Secondhand smoke exposure (SHSe) is a known cause of many adverse health effects in adults and children. Increasingly, SHSe assessment is an element of tobacco control research and implementation worldwide. In spite of decades of development of approaches to assess SHSe, there are still unresolved methodological issues; therefore, a multidisciplinary expert meeting was held to catalogue the approaches to assess SHSe and with the goal of providing a set of uniform methods for future use by investigators and thereby facilitate comparisons of findings across studies. The meeting, held at Johns Hopkins, in Baltimore, Maryland, USA, was supported by the Flight Attendant Medical Research Institute (FAMRI). A series of articles were developed to summarise what is known about self-reported, environmental and biological SHSe measurements. Non-smokers inhale toxicants in SHS, which are mainly products of combustion of organic materials and are not specific to tobacco smoke exposure. Biomarkers specific to SHSe are nicotine and its metabolites (e.g., cotinine), and metabolites of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Cotinine is the preferred blood, saliva and urine biomarker for SHSe. Cotinine and nicotine can also be measured in hair and toenails. NNAL (4-[methylnitrosamino]-1-[3-pyridyl]-1-butanol), a metabolite of NNK, can be determined in the urine of SHS-exposed non-smokers. The selection of a particular biomarker of SHSe and the analytic biological medium depends on the scientific or public health question of interest, study design and setting, subjects, and funding. This manuscript summarises the scientific evidence on the use of biomarkers to measure SHSe, analytical methods, biological matrices and their interpretation.

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) metabolism-related enzymes gene polymorphisms, NNK metabolites levels and urothelial carcinoma

Gene polymorphisms of the 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) metabolism-related enzymes-cytochrome P450 (CYP) monooxygenase 2A13 (CYP2A13) and UDP-glucuronosyltransferases (UGT)-2B7 could contribute to the levels of NNK-related metabolites in urine, thereby increasing the susceptibility to urothelial carcinoma (UC). Therefore, our study aimed to evaluate the roles of two gene polymorphisms (CYP2A13 and UGT2B7) of NNK metabolism-related enzymes in the carcinogenesis of UC in Taiwan. A hospital-based pilot case-control study was conducted. There were 121 UC cases and 121 age- and sex-matched healthy participants recruited from March 2007 to April 2009. Urine samples were analyzed for NNK-related metabolites using the liquid chromatography-tandem mass spectrometry method. Genotyping was conducted using a polymerase chain reaction-restriction fragment length polymorphism technique. ANCOVA and multivariate logistic regression were applied for data analyses. In healthy controls, former smokers had significantly higher total NNAL and higher NNAL-Gluc than never smokers or current smokers. Subjects carrying the UGT2B7 268 His/Tyr or Tyr/Tyr genotype had significantly lower total NNAL than those carrying His/His genotype. However, no association was seen between gene polymorphisms of CYP2A13 and UGT2B7 and UC risk after adjustment for age and sex. Significant dose -response associations between total NNAL, free NNAL, the ratios of free NNAL/total NNAL and NNAL-Gluc/total NNAL and UC risk were observed. In the future, large-scale studies will be required to verify the association between the single nucleotide polymorphisms of NNK metabolism-related enzymes and UC risk.

Exposure to secondhand smoke outside of a bar and a restaurant and tobacco exposure biomarkers in nonsmokers

BACKGROUND

With an increase in indoor smoking bans, many smokers smoke outside establishments and near their entrances, which has become a public health concern.

OBJECTIVES

We characterized the exposure of nonsmokers to secondhand smoke (SHS) outside a restaurant and bar in Athens, Georgia, where indoor smoking is banned, using salivary cotinine and urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL).

METHODS

In a crossover study, we assigned 28 participants to outdoor patios of a restaurant and a bar and an open-air site with no smokers on three weekend days; participants visited each site once and stayed for 3 hr. We collected saliva and urine samples immediately before and after the visits (postexposure) and on the following morning and analyzed samples for cotinine and total NNAL, respectively. Regression models were fitted and changes in biomarkers were contrasted between locations.

RESULTS

Postexposure and preexposure geometric mean salivary cotinine concentrations differed by 0.115 ng/mL [95% confidence interval (CI): 0.105, 0.126)] and by 0.030 ng/mL (95% CI: 0.028, 0.031) for bar and restaurant visits, respectively. There were no significant post- and preexposure differences in cotinine levels after control site visits, and changes after bar and restaurant site visits were significantly different from changes after control site visits (p < 0.001). Results comparing next-day and preexposure salivary cotinine levels were similar. Next-day creatinine-corrected urinary NNAL concentrations also were higher than preexposure levels following bar and restaurant visits [1.858 pg/mg creatinine higher (95% CI: 0.897, 3.758) and 0.615 pg/mg creatinine higher (95% CI: 0.210, 1.761), respectively], and were significantly different from changes after the control visits (p = 0.005).

CONCLUSION

Salivary cotinine and urinary NNAL increased significantly in nonsmokers after outdoor SHS exposure. Our findings indicate that such exposures may increase risks of health effects associated with tobacco carcinogens.

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.

Methods in tobacco abuse: proteomic changes following second-hand smoke exposure

Smoking is one of the leading preventable causes of disease, disability, and death in the USA and leads to more than 400,000 preventable deaths per year. Nicotine is the major alkaloid present in tobacco smoke, and many of the negative effects of smoking are attributed to nicotine. Nicotine is not only the addictive component of tobacco smoke, but also highly associated with carcinogenesis and induces oxidative stress. Furthermore, the administration of nicotine via subcutaneous mini-osmotic pumps or by injection is an established method in preclinical studies for this area of research. Thus, preclinical research on the negative effects of tobacco smoke and tobacco addiction has focused primarily on the effects of nicotine. However, there are over 4,500 components found in tobacco smoke, many of which are highly toxic. Other components may also contribute to the addictive properties of tobacco smoke. Furthermore, the negative effects of tobacco smoke are not isolated to the smoker but can have negative effects to those exposed to the secondhand smoke (SHS) stream. SHS exposure is the third leading cause of preventable death. Approximately 38,000 deaths per year are attributed to SHS exposure in the USA. SHS exposure increases the risk of heart disease by approximately 30% and is associated with increased risk of stroke, cancer, type II diabetes, as well as pulmonary disease. Thus, methods of administering tobacco smoke in a controlled environment will further our understanding of tobacco addiction and the role tobacco smoke in other disease states. Moreover, combining smoke exposure with proteomics can lead to the discovery of biomarkers that can be potentially useful tools in screening, early diagnosis, prevention, and treatment of diseases caused by SHS.

Intervention to promote smoke-free policies among multiunit housing operators

OBJECTIVE

To assess the efficacy of an intervention to encourage the adoption of smoke-free policies among owners and managers of multiunit housing.

DESIGN

A pretest-posttest quasi-experimental design was employed.

PARTICIPANTS

The study population included 287 multiunit housing operators (MUHOs) from across New York State who were recruited to complete a baseline survey designed to assess policies about smoking in the housing units that they owned and/or managed. Subjects were surveyed between March and July 2008 (n = 128 intervention, n = 159 control) and recontacted 1 year later to complete a follow-up survey (n = 59 intervention, n = 95 control).

INTERVENTION

An informational packet on the benefits of implementing a smoke-free policy was mailed to MUHOs in the New York State counties of Erie and Niagara between March and July 2008. For comparison purposes, a sample of MUHOs located outside of Erie and Niagara counties who did not receive the information packet were identified to serve as control subjects.

MAIN OUTCOME MEASURES

Logistic regression was used to assess predictors of policy interest, concern, and implementation at follow-up. Predictors included: intervention group, baseline status, respondent smoking status, survey type, government-subsidy status, quantity of units operated, and average building size, construction type, and age.

RESULTS

Multiunit housing operators who received the information packet were more likely to report interest in adopting a smoke-free policy (OR = 6.49, 95% CI = 1.44-29.2), and less likely to report concerns about adopting such a policy (OR = 0.16, 95% CI = 0.04-0.66) compared to MUHOs who did not receive the information packet; however, the rate of adoption of smoke-free policies was comparable between the groups.

CONCLUSION

Sending MUHOs an information packet on the benefits of adopting a smoke-free policy was effective in addressing concerns and generating interest toward smoke-free policies but was not sufficient in itself to generate actual policy adoption.

The ratio of a urinary tobacco-specific lung carcinogen metabolite to cotinine is significantly higher in passive than in active smokers

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol plus its glucuronides (total NNAL), metabolites of the lung carcinogen NNK, and total cotinine, metabolites of nicotine, are biomarkers of active and passive cigarette smoking. We calculated the total NNAL:total cotinine (×10(3)) ratio in 408 passive (infants, children, and adults) and 1088 active smokers. The weighted averages were 0.73 (95% confidence interval 0.71, 0.76) for passive smokers and 0.07 (0.06, 0.08) for active smokers (p < 0.0001). These results demonstrate that cotinine measurements may underestimate exposure of passive smokers to the lung carcinogen NNK in second-hand cigarette smoke. The total NNAL:total cotinine (×10(3)) ratio may provide an improved biomarker for evaluating the health effects of passive smoking.

Association of secondhand smoke exposures with DNA methylation in bladder carcinomas

BACKGROUND

The association between secondhand smoke (SHS) exposure and bladder cancer is inconclusive. Epigenetic alterations in bladder tumors have been linked to primary cigarette smoking and could add to the biological plausibility of an association between SHS exposure and bladder cancer.

HYPOTHESIS

SHS exposure is associated with DNA methylation in bladder tumors.

METHODS

Using an array-based approach, we profiled DNA methylation from never smoking cases of incident bladder cancer. Analyses examined associations between individual loci's methylation with SHS variables (exposure in adulthood, childhood, occupationally, and total exposure). A canonical pathway analysis was used to find pathways significantly associated with each SHS exposure type.

RESULTS

There is a trend toward increased methylation of numerous CpG loci with increasing exposure to adulthood, occupational, and total SHS. Discrete associations between methylation extent of several CpG loci and SHS exposures demonstrated significantly increased methylation of these loci across all types of SHS exposure. CpGs with SHS-related methylation alterations were associated with genes in pathways involved in carcinogenesis, immune modulation, and immune signaling.

INTERPRETATION

Exposures to SHS in adulthood, childhood, occupationally, and in total are each significantly associated with changes in DNA methylation of several CpG loci in bladder tumors, adding biological plausibility to SHS as a risk factor for bladder cancer.

Exposure to environmental tobacco smoke in childhood and incidence of cancer in adulthood in never smokers in the European Prospective Investigation into Cancer and Nutrition

The association between childhood environmental tobacco smoke (ETS) exposure and adult cancer risk is controversial; we examined this relationship in never smokers within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Over an average of 10 years, 8,372 cases of cancer were diagnosed in 112,430 never smokers in EPIC. Childhood ETS was self-reported by participants at baseline, along with other lifestyle factors. Hazard ratios (HR) for ETS exposure in childhood and their 95% confidence intervals (CI) were estimated by Cox proportional hazards models stratified by age, sex, and study center and adjusted for education, alcohol drinking, body mass index, physical activity, non-alcoholic energy intake, fruit and vegetable intake, and adulthood ETS exposure. Models were further adjusted for reproductive factors for female cancers, for meat intake for digestive system cancers, and for diabetes status for pancreatic cancer. No association was observed between childhood ETS exposure and overall cancer risks (HR = 0.97, 95% CI = 0.92-1.02), and for selected sites. The only exception was pancreatic cancer, as previously reported by Vrieling et al., among those who had been exposed daily in childhood (overall HR = 2.09, 95% CI = 1.14-3.84). In conclusion, childhood ETS exposure might not be a major risk factor for common cancers in adulthood.

Nicotine dependence and quitting behaviors among menthol and non-menthol smokers with similar consumptive patterns

AIMS

This study examines the associations between usual cigarette brand (i.e. menthol, non-menthol) and markers for nicotine dependence and quitting behaviors.

DESIGN

The 2003 and 2006/07 Tobacco Use Supplements to the Current Population Surveys were pooled to conduct secondary data analysis.

SETTING

National data were collected using in-person and telephone computer-assisted interviews by the United States Census Bureau among civilian, non-institutionalized people aged 15 years and older.

PARTICIPANTS

Data were analyzed among daily current smokers aged 18+ (n = 46,273).

MEASUREMENTS

The associations between usual cigarette brand and time to first cigarette within 5 and 30 minutes after waking, quit attempts in the past 12 months and length of smoking abstinence in the past 12 months were examined. Bivariate and multivariate logistic regression models were stratified by smoking intensity: ≤5, 6-10, 11-19 and 20+ cigarettes per day.

FINDINGS

Menthol smokers reported a mean of 13.05 compared with 15.01 cigarettes per day among non-menthol smokers (P < 0.001). Multivariate results showed that among smokers consuming 6-10 cigarettes per day, menthol smokers were significantly more likely than non-menthol smokers to consume their first cigarette within 5 minutes after waking (odds ratio = 1.22, 95% confidence interval = 1.05,1.43). The multivariate models did not show significant associations between usual cigarette brand and quit attempts in past 12 months or duration of smoking abstinence >2 weeks in the past 12 months.

CONCLUSIONS

Findings from this national survey of daily smokers demonstrate that menthol smokers in the United States who report consuming 6-10 cigarettes per day show greater signs of nicotine dependence than comparable non-menthol smokers.

Secondhand smoke transfer in multiunit housing

INTRODUCTION

The home can represent a significant source of secondhand smoke (SHS), especially for individuals who live in close proximity to one another in multiunit housing (MUH). The objective of this study was to quantify real-time SHS transfer between smoke-permitted and smoke-free living units within the same MUH structure.

METHODS

Air monitors were used to assess PM₂.₅, an environmental marker for SHS, in 14 smoke-free living units and 16 smoke-permitted units within 11 MUH buildings in the Buffalo, New York, area between July 2008 and August 2009. Air monitors were operated concurrently in both smoke-permitted and smoke-free units within each building. When feasible, additional monitors were stationed in shared hallways and on outdoor patios. Participants completed logs to document activities that could affect air quality.

RESULTS

Evidence of SHS transfer from smoke-permitted units was detected in 2 of the 14 smoke-free units and 6 of the 8 hallways. Real-time PM₂.₅ plots and participant logs suggest that SHS transfer is a function of many determinants, including ventilation and proximity between units. Following stratification by time of day, median PM₂.₅ levels were greatest between 4:00 PM and 11:59 PM but varied by location: 10.2 μg/m³ in smoke-free units, 18.9 μg/m³ in hallways, and 29.4 μg/m³ in smoke-permitted units.

CONCLUSIONS

This study documents SHS incursions from smoke-permitted units into smoke-free units and adjacent hallways within the same building. Since many factors appear to impact the amount of SHS transfer between these areas, the implementation of a smoke-free building policy represents the most effective way to ensure that residents of MUH units are not exposed to SHS.

Active and Passive Smoking and the Risk of Pancreatic Cancer in the Netherlands Cohort Study

Background: To date, cigarette smoking is the most consistent risk factor for pancreatic cancer. We prospectively examined the role of active cigarette smoking, smoking cessation, and passive smoking as determinants for pancreatic cancer.

Methods: The Netherlands Cohort Study consisted of 120,852 men and women who completed a baseline questionnaire in 1986. After 16.3 years of follow-up, 520 incident pancreatic cancer cases were available for analysis. A case-cohort approach was employed using the person-years of follow-up of a random subcohort (n = 5,000), which was chosen immediately after baseline.

Results: Compared with never cigarette smokers, both former and current cigarette smokers had an increased pancreatic cancer risk [multivariable-adjusted hazard rate ratio (HR), 1.34; 95% confidence interval (CI), 1.02-1.75 and HR, 1.82; 95% CI, 1.40-2.38, respectively]. We observed an increased pancreatic cancer risk per increment of 10 years of smoking (HR, 1.15; 95% CI, 1.08-1.22) and an HR of 1.08 per increment of 10 cigarettes/d (95% CI, 0.98-1.19). Quitting smoking gradually reduced pancreatic cancer risk and approached unity after ≥20 years of quitting. No association was observed for passive smoking exposure and pancreatic cancer risk in women; in men, this association was not investigated because &gt;90% of the men were ever smokers.

Conclusions: Overall, our findings confirmed that cigarette smoking is an important risk factor for pancreatic cancer, whereas quitting smoking reduced risk. No association was observed between passive smoking exposure and pancreatic cancer risk in women.

Impact: Quitting smoking would benefit the burden on pancreatic cancer incidence. Cancer Epidemiol Biomarkers Prev; 19(6); 1612–22. ©2010 AACR.

Multiunit housing residents' experiences and attitudes toward smoke-free policies

INTRODUCTION

Secondhand smoke (SHS) causes significant disease and death. A person's home represents a prominent source of SHS, and the potential for exposure is elevated among those who live in close proximity to smokers in multiunit housing (MUH). This study assessed the prevalence and predictors of SHS exposure and smoke-free policy support among MUH residents.

METHODS

Data were obtained from 5,936 MUH residents who participated in the New York State Adult Tobacco Survey between May 2007 and May 2009. Bivariate analyses were used to assess the prevalence of smoke-free home policies, SHS incursions, and support for smoke-free policies. Logistic regression was used to identify predictors of these measures while adjusting for gender, age, ethnicity, education, region, children in household, and housing type.

RESULTS

A total of 73.1% of respondents reported a personal smoke-free home policy in their home. Among these individuals, 46.2% indicated that SHS has ever entered their home in the past year, while 9.2% reported daily incursions. Overall, a majority of respondents (55.6%) support a policy that bans smoking in all areas of their building, including residential units; support was significantly higher among ethnic minorities and individuals who reside with children.

DISCUSSION

Nearly half of New York MUH residents with a smoke-free home policy have experienced a SHS incursion in their home. Since a majority of MUH residents support smoke-free policies and nearly three quarters already prohibit smoking in their home, opportunities exist for initiatives to promote smoke-free building policies.

A review of the analysis of tobacco-specific nitrosamines in biological matrices

Tobacco use constitutes a leading cause of mortality and morbidity worldwide. Tobacco-specific nitrosamines (TSNAs) are an important class of biomarkers for tobacco carcinogen uptake. The current review focuses on the issues and developments in analysis of these compounds in human biological matrices. The two most widely used techniques for TSNA bioanalysis are gas chromatography coupled with thermal energy analysis and liquid chromatography coupled with mass spectrometry, employing various sample preparation techniques. The review provides an overview of the tools and techniques currently available for TSNA bioanalysis that will help towards the ultimate goal of understanding the mechanisms of cancer caused by the use of tobacco products. A contrast and comparison of the important aspects of bioanalysis such as sample preparation, compound detection, and throughput is discussed for the thermal energy analysis- and mass spectrometry-based techniques. Complex sample extraction procedures, throughput, and the ability to validate are important issues of concern for the gas chromatography-thermal energy analysis-based methods. On the other hand, addressing ion suppression matrix effects remains an important challenge for hyphenated mass spectrometry-based methods. The review also provides an extensive summary of analytical procedures for various studies measuring tobacco-specific nitrosamines in different biological matrices.

Bar Patronage after a Smoking Ban

On May 1, 2005, the city of Flagstaff, Arizona enacted a smoking ban in standalone bars. All other establishments already had smoking bans in place for at least three years. Trained observers carried air monitoring equipment and counted lit cigarettes and patrons on two weekends before and four weekends after the ban. Monthly hospitality revenues from 2003 to 2006 were also collected from the Coconino County Tax Assessor's office and analyzed for changes after the ban. Air quality improved immediately by 87% in bars, with no appreciable decrease in the total bar revenues over the next three years. All hospitality businesses experienced a general leveling off of growth after the ban, suggesting a change in more general economic factors. As an industry, hospitality was unaffected by the smoking ban, though individual establishments could have been adversely affected. The standalone bar industry revenue continued to increase after the ban. Alcohol and cigarette co-consumption was not supported.

Increases in tobacco exposure biomarkers measured in non-smokers exposed to sidestream cigarette smoke under controlled conditions

National surveys of the exposure of non-smokers to secondhand smoke based on serum cotinine analyses have consistently identified certain groups within the population including children, males and non-Hispanic Blacks as having relatively greater exposure. Although these differences in mean serum cotinine concentrations probably represent differences in exposure of individuals in their daily lives, it is also possible that metabolic or other differences in response might influence the results. To better define the nature of those findings, we have examined the response of 40 non-smokers including both men and women and African-Americans and whites to sidestream (SS) cigarette smoke generated by a smoking machine under controlled conditions. In this study, participants were exposed to aged, diluted SS smoke (ADSS) generated in an environmental chamber with a mean air nicotine concentration of 140 microg m(-3) and 8.6 ppm CO for 4 h. Salivary cotinine was measured every 30 min, and serum cotinine samples were taken prior to, and 2 h after exposure. Urinary nicotine metabolites and NNAL, a tobacco-specific nitrosamine, and 4-aminobiphenyl (4-AB) haemoglobin adducts were also measured prior to and 2 h following the exposure. Under these uniform, controlled conditions, we found a similar response to ADSS smoke exposure among all the participants. In all cases a significant increase in biomarker concentration was noted following exposure, and the short-term increases in salivary cotinine concentration were quite similar at approximately 12 pg ml(-1) min(-1) among the groups. In this small study, no significant differences by gender or race were seen in the mean increases observed in cotinine, NNAL or 4-AB adducts following 4 h of exposure. Thus, our results are most consistent with a relatively uniform response in tobacco biomarker concentrations following short-term exposure to ADSS tobacco smoke, and suggest that biomarker measurements are capable of effectively indicating increases in exposure among groups of non-smokers.

Lung cancer and women

In the early 1900s, lung cancer was a rare malignancy in women, but starting from the 1960s it has progressively reached epidemic proportions, surpassing breast cancer in 1987 and becoming the leading cause of cancer deaths in many countries. Retrospective data show that the 5-year survival rate for women who have lung cancer is 15.6%, compared with 12.5% for men, and this improved survival could have important implications in the design and interpretation of lung cancer trials. Women have major responses to therapy regardless of stage, therapeutic modalities or histology. The increase of lung cancer incidence among women is reflected in their clinical trial participation, causing a survival improvement and suggesting the need of stratification by sex in future studies. No specific drugs for women with lung cancer are currently available, but researchers are devoting energies in this area in order to better understand the implication of gender differences in epidemiology, pathogenesis, prognosis and tumor response.

Women and lung cancer: clinical and molecular profiling as a determinate for treatment decisions: a literature review

In the past decade the incidence of lung cancer among women has risen, whereas among men it has slightly declined. Important differences in lung cancer have been demonstrated between men and women, although many areas still remain controversial. Some biologic differences may justify the increase in response of women to therapy for lung cancer and can partially explain the improved survival of women compared with men. We extensively reviewed the published scientific literature on this topic in order to investigate the clinical and genetic profiling underlying lung cancer in women and to use this information as a tool for medical therapy.

Detection and quantitation of N'-nitrosonornicotine in human toenails by liquid chromatography-electrospray ionization-tandem mass spectrometry

Specific biomarkers of tobacco carcinogen uptake are critical for investigations of the role of tobacco smoke exposure in human cancers. Two new biomarkers of human exposure to tobacco-specific carcinogens have been recently developed by our research group: urinary N'-nitrosonornicotine (NNN) and toenail 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL). In this study, we report the presence of NNN in human toenails. Toenails of 17 smokers were analyzed for total NNN. Mean total NNN level in these samples was 4.63 +/- 6.48 fmol/mg toenail and correlated with previously reported total NNAL (r = 0.96; P < 0.0001), total nicotine (r = 0.48; P < 0.05), and total cotinine (r = 0.87; P < 0.0001). An interesting finding was that amounts of NNN in smokers' toenails were generally higher than those of total NNAL. The ratio of toenail NNN to NNAL averaged 2.8, whereas the previously reported ratio between these biomarkers in smokers' urine was 0.1. NNN was also found in toenail samples from 12 nonsmokers, averaging 0.35 +/- 0.16 fmol/mg and positively correlating with toenail cotinine (r = 0.58; P = 0.05). The results of this study show the feasibility of quantifying NNN in human toenails, providing a potentially useful new biomarker of tobacco carcinogen exposure.

Second hand smoke, age of exposure and lung cancer risk

BACKGROUND

Exposure to second hand smoke (SHS) has been identified as a risk factor for lung cancer for three decades. It is also known that the lung continues to grow from birth to adulthood, when lung growth stops. We hypothesize that after adjusting for active cigarette smoking, if SHS exposure took place during the period of growth, i.e. in the earlier part of life (0-25 years of age) the risk of lung cancer is greater compared to an exposure occurring after age 25.

METHOD

Second hand smoke exposure was self-reported for three different activities (leisure, work and at home) for this study population of 1669 cases and 1263 controls. We created variables that captured location of exposure and timing of first exposure with respect to a study participant's age (0-25, >25 years of age). Multiple logistic regressions were used to study the association between SHS exposure and lung cancer, adjusting for age, gender and active smoking variables.

RESULT

For study participants that were exposed to SHS at both activities (work and leisure) and compared to one or no activity, the adjusted odds ratio (AOR) for lung cancer was 1.30 (1.08-1.57) when exposure occurred between birth and age 25 and 0.66 (0.21-1.57) if exposure occurred after age 25 years. Respective results for non-smokers were 1.29 (0.82-2.02) and 0.87 (0.22-3.38), and current and ex-smokers combined 1.28 (1.04-1.58) and 0.66 (0.15-2.85).

CONCLUSION

All individuals exposed to SHS have a higher risk of lung cancer. Furthermore, this study suggests that subjects first exposed before age 25 have a higher lung cancer risk compared to those for whom first exposure occurred after age 25 years.

Smoke-free spaces over time: a policy diffusion study of bylaw development in Alberta and Ontario, Canada

Policy diffusion is a process whereby political bodies 'learn' policy solutions to public health problems by imitating policy from similar jurisdictions. This suggests that diffusion is a critical element in the policy development process, and that its role must be recognised in any examination of policy development. Yet, to date, no systematic work on the diffusion of smoke-free spaces bylaws has been reported. We examined the diffusion of municipal smoke-free bylaws over a 30-year period in the provinces of Alberta and Ontario, Canada, to begin to address this gap and to determine whether spatial patterns could be identified to help explain the nature of policy development. Bylaw adoption and change were analysed within local, regional, and provincial contexts. Geographical models of hierarchical and expansion diffusion in conjunction with the diffusion of innovations framework conceptually guided the analyses. Study findings contribute to a broader understanding of how and why health policies diffuse across time and place. Policy development can be a powerful mechanism for creating environments that support healthy decisions; hence, an understanding of policy diffusion is critical for those interested in policy interventions aimed at improving population health in any jurisdiction.

Progress and challenges in selected areas of tobacco carcinogenesis

Tobacco use continues to be a major cause of cancer in the developed world, and despite significant progress in this country in tobacco control, which is driving a decrease in cancer mortality, there are still over 1 billion smokers in the world. This perspective discusses some selected issues in tobacco carcinogenesis focusing on progress during the 20 years of publication of Chemical Research in Toxicology. The topics covered include metabolism and DNA modification by tobacco-specific nitrosamines, tobacco carcinogen biomarkers, an unidentified DNA ethylating agent in cigarette smoke, mutations in the K-RAS and p53 gene in tobacco-induced lung cancer and their possible relationship to specific carcinogens, secondhand smoke and lung cancer, emerging issues in smokeless tobacco use, and a conceptual model for understanding tobacco carcinogenesis. It is hoped that a better understanding of mechanisms of tobacco-induced cancer will lead to new and useful approaches for the prevention of lung cancer and other cancers caused by tobacco use.

Relationship of human toenail nicotine, cotinine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol to levels of these biomarkers in plasma and urine

Recently, we developed sensitive and quantitative methods for analysis of the biomarkers of tobacco smoke exposure nicotine, cotinine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) in human toenails. In this study, we further evaluated the newly developed toenail biomarkers by investigating their relationship to demographic factors, reported exposure, plasma nicotine, cotinine, and trans-3'-hydroxycotinine, and urinary NNAL. Toenails of 105 smokers, mean age 38.9 years (range, 19-68), were analyzed. Fifty-five (53.4%) were male, with approximately equal numbers of Whites and African-Americans. The average number of cigarettes smoked per day was 18 (range, 5-50). There was no effect of age or gender on the toenail biomarkers. Toenail NNAL was higher in White than in African-American participants (P = 0.019). Toenail nicotine and toenail cotinine correlated significantly with cigarettes smoked per day (r = 0.24; P = 0.015 and r = 0.26; P = 0.009, respectively). Toenail nicotine correlated with plasma nicotine (r = 0.39; P < 0.001); toenail cotinine correlated with plasma cotinine (r = 0.45; P < 0.001) and plasma trans-3'-hydroxycotinine (r = 0.30; P = 0.008); and toenail NNAL correlated with urine NNAL (r = 0.53; P = 0.005). The results of this study provide essential validation data for the use of toenail biomarkers in investigations of the role of chronic tobacco smoke exposure in human cancer.

Urinary biomarkers to assess exposure of cats to environmental tobacco smoke

OBJECTIVE

To evaluate the use of urinary biomarkers to assess exposure of cats to environmental tobacco smoke (ETS).

ANIMALS

61 healthy client-owned cats (19 from households in which smoking was reported and 42 from households in which there was no smoking).

PROCEDURES

Urine samples were obtained from each cat and assayed for total nicotine (nicotine plus nicotine glucuronide) and total cotinine (cotinine plus cotinine glucuronide) content by use of gas chromatography-mass spectrometry. In addition, total urinary content of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), a major metabolite of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, was measured by use of gas chromatography with nitrosamine-selective detection.

RESULTS

Cats from households in which smoking was reported had significantly higher concentrations of total nicotine (70.4 ng/mL), total cotinine (8.53 ng/mL), and total NNAL (0.0562 pmol/mL) in urine, compared with concentrations for cats that lived in households in which there was no smoking (4.89 ng/mL, 0.74 ng/mL, and 0.0182 pmol/mL, respectively).

CONCLUSIONS AND CLINICAL RELEVANCE

Analysis of these data provided biochemical evidence of exposure to ETS and uptake of tobacco-specific carcinogens by cats that live in households with smokers. Biomarkers could facilitate investigation of the health effects of ETS in cats and other species.

The impact of clean indoor air exemptions and preemption policies on the prevalence of a tobacco-specific lung carcinogen among nonsmoking bar and restaurant workers

OBJECTIVES

We studied the impact of clean indoor air law exemptions and preemption policies on the prevalence of a tobacco-specific lung carcinogen-4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)--among nonsmoking bar and restaurant workers.

METHODS

secondhand smoke were compared with results from participants who were exposed to it.

RESULTS

Participants exposed to workplace secondhand smoke were more likely to have any detectable level of NNAL (P=.005) and higher mean levels of NNAL (P < .001) compared with nonexposed participants. Increased levels of NNAL were also associated with hours of a single workplace exposure (P=.005).

CONCLUSIONS

Nonsmoking employees left unprotected from workplace secondhand smoke exposure had elevated levels of a tobacco-specific carcinogen in their bodies. All workers--including bar and restaurant workers--should be protected from indoor workplace exposure to cancer-causing secondhand smoke.

Mass spectrometric quantitation of nicotine, cotinine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol in human toenails

Numerous studies have quantified total cotinine (the sum of cotinine and cotinine-N-glucuronide) and total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol [NNAL; the sum of NNAL and its O- and N-glucuronides (NNAL-Glucs)] in the urine and blood of smokers, smokeless tobacco users, and nonsmokers exposed to environmental tobacco smoke. Analysis of hair and nails has several advantages over blood and urine testing, such as accumulation of xenobiotics during long-term exposure, ease of collection, and indefinite stability of samples. We developed sensitive methods for quantitation of nicotine, cotinine, and NNAL in human toenails. Nicotine and cotinine were analyzed by gas chromatography-mass spectrometry-selected ion monitoring. NNAL was assayed using liquid chromatography-electrospray ionization-tandem mass spectrometry-selected reaction monitoring. The detection limits of the methods were 0.01 ng/mg toenail for nicotine, 0.012 ng/mg toenail for cotinine, and 0.02 pg/mg toenail for NNAL. In 35 smokers, the mean nicotine level was 5.9 +/- 5.6 ng/mg toenail, mean cotinine was 1.6 +/- 1.3 ng/mg toenail, and mean NNAL was 0.41 +/- 0.67 pg/mg toenail. Samples collected from six nonsmokers were negative for NNAL. In smokers, NNAL correlated with cotinine (r = 0.77; P < 0.0001). The results of this study for the first time show the presence of cotinine and NNAL in human toenails. These sensitive and quantitative methods should be useful in epidemiologic studies of the role of chronic tobacco smoke exposure, including environmental tobacco smoke exposure, in human cancer.

A solution for the most basic optimization problem associated with an ROC curve

In a few cases, such as early pregnancy tests, the test results are dichotomous; many diagnostic tests, however, give results which are not binary. In the diagnosis of prostate cancer, prostate-specific antigen test result is on a continuous scale; or, in radiology, assessment of mammograms is on an ordinal scale. In such cases, the accuracy of the marker or test is often first summarized in a receiver operating characteristic (ROC) curve and then as the area under that curve. The area under the ROC curve, however, only shows the 'potential' of a marker; sooner or later, for practical uses, we still need to dichotomize the test result so that we can classify subjects as 'diseased' or 'healthy'. Finding an 'optimal' cutpoint to dichotomize a continuous marker is desirable and is a very basic problem but, in all or most cases, cutpoints used in practice are arbitrary. The difficulty lies in our failure to define and justify a criterion for optimality. In this paper, we will propose a solution by maximizing a well-known parameter--the Youden's Index--within the framework of the ROC curve.

4-(Methylnitrosamino)-I-(3-Pyridyl)-1-Butanone Enhances the Expression of Apolipoprotein A-I and Clara Cell 17-kDa Protein in the Lung Proteomes of Rats Fed a Corn Oil Diet but not a Fish Oil Diet

The nicotine-derived nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is one of the most potent lung carcinogens in rodents. Several epidemiologic studies indicated that the development of lung cancer in smokers is influenced by the type and amount of dietary polyunsaturated fatty acids. A high corn oil diet has been shown to increase lung tumor volume and to decrease tumor latency in rats treated with NNK. In this study, we investigated the effects of dietary polyunsaturated fatty acids in the form of corn oil or fish oil on lung proteomes in F344 rats treated with or without NNK. The fish oil diet contained 17% fish oil and 3% corn oil, and the corn oil diet contained 20% corn oil. Rats were sacrificed after 3 months, and lungs were excised. Whole lung tissue proteins were separated by two-dimensional liquid chromatography, and differentially expressed proteins were identified by trypsin digestion and tandem mass spectrometry. Apolipoprotein A-I and Clara cell 17-kDa protein were overexpressed in the lungs of rats fed corn oil diet, compared with fish oil diet. NNK further enhanced their expression in rats fed corn oil diet; this effect was not observed in animals fed fish oil diet. The results suggest that the elevated levels of apolipoprotein A-I and Clara cell 17-kDa protein may be involved in the development of NNK-induced lung cancer in rats fed a high corn oil diet. Therefore, we propose that both proteins may serve as potential biomarkers in future molecular epidemiologic and clinical chemoprevention intervention studies.

4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and its glucuronides in the urine of infants exposed to environmental tobacco smoke

Biomarkers of carcinogen uptake could provide important information pertinent to the question of exposure to environmental tobacco smoke (ETS) in childhood and cancer development later in life. Previous studies have focused on exposures before birth and during childhood, but carcinogen uptake from ETS in infants has not been reported. Exposures in infants could be higher than in children or adults because of their proximity to parents who smoke. Therefore, we quantified 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and its glucuronides (total NNAL) in the urine of 144 infants, ages 3 to 12 months, who lived in homes with parents who smoked. Total NNAL is an accepted biomarker of uptake of the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. Cotinine and its glucuronide (total cotinine) and nicotine and its glucuronide (total nicotine) were also quantified. Total NNAL was detectable in 67 of 144 infants (46.5%). Mean levels of total NNAL in the 144 infants were 0.083 +/- 0.200 pmol/mL, whereas those of total cotinine and total nicotine were 0.133 +/- 0.190 and 0.069 +/- 0.102 nmol/mL, respectively. The number of cigarettes smoked per week in the home or car by any family member when the infant was present was significantly higher (P < 0.0001) when NNAL was detected than when it was not (76.0 +/- 88.1 versus 27.1 +/- 38.2). The mean level of NNAL detected in the urine of these infants was higher than in most other field studies of ETS exposure. The results of this study show substantial uptake of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in infants exposed to ETS and support the concept that persistent ETS exposure in childhood could be related to cancer later in life.

A biomarker of exposure to environmental tobacco smoke (ETS) and Ernst Wynder's opinion about ETS and lung cancer

Ernst Wynder did not believe that environmental tobacco smoke (ETS), also known as secondhand smoke, was a cause of lung cancer because his own data did not support this. His view on the issue may have begun to change with our initial studies, carried out at the American Health Foundation, showing that metabolites of the tobacco-specific lung carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) were present in the urine of non-smokers exposed to ETS. The metabolites - 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and its glucuronides (NNAL-Glucs) - have now emerged as leading biomarkers for the study of carcinogen exposure in non-smokers exposed to ETS. Subsequent work has consistently demonstrated elevated levels of NNAL plus NNAL-Glucs in the urine of people exposed to ETS in various field studies and throughout life. These studies strongly support the epidemiologic data demonstrating that ETS exposure causes lung cancer in non-smokers and have likely had an impact on tobacco control.