Method validation for measurement of hair nicotine level in nonsmokers

Tobacco Smoke Exposure According to Location of Home Smoking in Israel: Findings from the Project Zero Exposure Study

Young children are particularly vulnerable to harms from tobacco smoke exposure (TSE). This study aimed to compare TSE: (1) between children who live in smoking families and those who do not; and (2) among children who live in smoking households with varying smoking locations. The data came from two studies that were conducted concurrently in Israel (2016-2018). Study 1: a randomized controlled trial of smoking families (n = 159); Study 2: a cohort study of TSE among children in non-smoking families (n = 20). Hair samples were collected from one child in each household. Baseline hair nicotine data were analyzed for 141 children in Study 1 and 17 children in Study 2. Using a logistic regression analysis (exposed vs. not exposed as per laboratory determination) and a linear regression (log hair nicotine), we compared TSE between: (1) children in Study 1 vs. Study 2; (2) children in families with different smoking locations in Study 1: balcony; garden, yard, or other place outside of the home; or inside the home (designated smoking areas within the home (DSAs) or anywhere). A higher proportion of children living in smoking households were measurably exposed to tobacco smoke (68.8%) compared to children living in non-smoking households (35.3%, p = 0.006). Among children from smoking families, 75.0% of those whose parents smoked in the house were exposed, while 61.8% of children whose parents restricted smoking to the porch (n = 55) were exposed, and 71.4% of those whose parents smoked outside the home (including gardens and yards) (n = 42) were exposed. In univariable and multivariable models, smoking location was not significantly associated with exposure. The majority of children in smoking families were measurably exposed to TSE, even if smoking was restricted to designated areas in the home, balconies, orgarden/yard/other outdoor areas. Reducing population smoking rates, particularly among parents, restricting smoking to at least 10 meters from homes and children, and denormalizing smoking around others are recommended to reduce population-level child TSE and tobacco-attributable disease and death.

A Review on Spike and Recovery Method in Analytical Method Development and Validation

In multidisciplinary science, Analytical approaches based on spike and recovery (SAR) play a substantial role in analytical testing. The spike and recovery method is an important technique for analyzing and accessing the accuracy of analytical methods. The goal of this review seeks to provide clarity on the role of SAR methods in the forensic science discipline. Recent literature has been searched from numerous databases like Google, Web of Sciences, Scopus, PubMed, Google Scholar, and SciFinder. Websites like Science Direct are critically explored to gather scientific reports related to SAR utility. This review discusses the applications and current role of the SAR methods in Forensic Toxicology. It is suggested as one of the major parameters in the validation of the analytical method. SAR methodology is extremely important for the identification and quantitation of analytes in the sample matrix. Moreover, the extension of SAR methods to any scientific discipline is equally important for quality assurance. All relevant processes like method development and its optimization, quality control, and assurance rely on SAR-based studies. However, the method requires better apprehension and needs to be utilized using standard guidelines.

Protecting Children From Tobacco Smoke Exposure: A Randomized Controlled Trial of Project Zero Exposure

INTRODUCTION

Young children are vulnerable to harm from tobacco smoke exposure (TSE). This study assessed the effect of Project Zero Exposure-an intervention program designed to help parents protect children from TSE-on children's exposure.

METHODS

Randomized controlled trial of a home-based, theory-driven intervention. Parents of young children (<8 y) in families with a smoking parent were eligible. The intervention included feedback on child TSE (hair nicotine), and home air quality (PM2.5), with motivational interviewing. Families were randomized to: intervention group (IG, N = 69), regular control group (RCG, N = 70), or to a secondary enhanced control group, (ECG, N = 20). Child hair samples were taken at baseline and follow-up. We report on child TSE in the IG versus RCG at six months.

RESULTS

Most enrolled families completed the trial (IG: 98.6%[68/69], RCG: 97.1%[68/70]). Log hair nicotine (LHN [ng/mg]) decreased in both the IG (Baseline: -1.78 ± 1.91, Follow-up: -2.82 ± 1.87, p = .003) and RCG (Baseline: -1.79 ± 1.54, Follow-up: -2.85 ± 1.73, p = .002), but did not differ between groups at study end (p = .635). Three of five parentally-reported outcomes showed improvement over time in the IG, and one in the RCG. Among IG participants, 90% found hair nicotine feedback useful.

CONCLUSIONS

No difference between the intervention and control groups was found on the objective biomarker, LHN. Child TSE decreased during the trial in intervention and control groups. Trial participation, which included hair nicotine monitoring, may have contributed to decreasing exposure in both groups. Concurrent control group improvements may partially explain lack of proven intervention benefit. Biomarker monitoring warrants further investigation for reduction of child TSE.

IMPLICATIONS

Project Zero Exposure is an intervention program designed to help parents protect their children from TSE. Results from the randomized controlled trial of the program showed no difference between groups at study end, but a clear and substantial reduction in child exposure to tobacco smoke from beginning to end of the trial, in both intervention and control groups. Biomarker monitoring, a key element of the trial, was used with all participants. Biomarker monitoring of child exposure to tobacco smoke may help parents become aware of their child's exposure and better protect them, and should be explored as a means to reduce child TSE. Clinical Trial Registration: NCT02867241.

Questionnaire-Based Environmental Tobacco Smoke Exposure and Hair Nicotine Levels in 6-month-old Infants: A Validation Study in Indonesia

Objectives. Using hair nicotine as the gold standard, this study aimed to establish cutoff points and validate the questionnaire-based environmental tobacco smoke (ETS) exposure and ETS statuses of Indonesian infants. Methods. A cross-sectional study design was conducted among families who were participants of the Peer Health Cohort Study in Jakarta, Indonesia. Households with 6-month-old infants joined this study. The presence and amount of ETS exposure were assessed by both questionnaire and hair sampling for nicotine determination. Head hair samples were collected from 102 infants and measured by optimized gas chromatography-mass spectrometry (GC/MS). Infants were grouped as ETS-exposed if they lived with at least 1 smoker at home. We used the receiver operating characteristic (ROC) curve to assess the sensitivity and specificity of cutoff values of hair nicotine. Results. There were 78 (76.5%) infants exposed to ETS based on the questionnaire. The nicotine concentrations in hair were significantly higher in infants with ETS exposure than in those without ETS exposure (P < .001). The area under the curve for nicotine was 0.774. A hair nicotine cutoff value of 2.37 ng/mg, with a sensitivity of 67.95% and specificity of 83.33%, was identified as the optimal cutoff value for separating exposed from non-exposed to ETS in infants. Conclusion. The hair nicotine value of infants aged 6 months is useful in confirming the questionnaire on smoking in the household and exposure to ETS. Moreover, it also could be used to distinguish ETS-exposed from non-ETS-exposed infants.

Parental Perceptions of Children's Exposure to Tobacco Smoke and Parental Smoking Behaviour

Around 40% of children are exposed to tobacco smoke, increasing their risk of poor health. Previous research has demonstrated misunderstanding among smoking parents regarding children's exposure. The parental perceptions of exposure (PPE) measure uses visual and textual vignettes to assess awareness of exposure to smoke. The study aimed to determine whether PPE is related to biochemical and reported measures of exposure in children with smoking parents. Families with at least one smoking parent and a child ≤ age 8 were recruited. In total, 82 parents completed the PPE questionnaire, which was assessed on a scale of 1-7 with higher scores denoting a broader perception of exposure. Parents provided a sample of their child's hair and a self-report of parental smoking habits. Parents who reported smoking away from home had higher PPE ratings than parents who smoke in and around the home (p = 0.026), constituting a medium effect size. PPE corresponded with home smoking frequency, with rare or no home exposure associated with higher PPE scores compared to daily or weekly exposure (p < 0.001). PPE was not significantly related to hair nicotine but was a significant explanatory factor for home smoking location. PPE was significantly associated with parental smoking behaviour, including location and frequency. High PPE was associated with lower exposure according to parental report. This implies that parental understanding of exposure affects protective behaviour and constitutes a potential target for intervention to help protect children.

Secondhand Smoke Exposure and Sleep-Related Breathing Problems in Toddlers

BACKGROUND

Adequate sleep during childhood is an important component of overall health and wellbeing for children. Secondhand smoke (SHS) exposure has been linked to a greater risk of sleep-disordered breathing.

OBJECTIVE

Our objective was to investigate relationships between SHS exposure and sleep-related breathing problems in healthy toddlers aged 2 to 5 years. We hypothesized that there is an independent relationship between objectively measured SHS exposure and presence of sleep-related breathing problems by parental report.

METHODS

A convenience sample of 149 healthy children ages 2 to 5 years was recruited from an academic pediatric primary care center for this cross-sectional study; 138 had complete data that were analyzed. Current SHS exposure was determined by hair nicotine level. Presence of sleep-related breathing problems was assessed by 1 survey item. Inflammation was determined by serum C-reactive protein (CRP) level. Analysis in Stata 15 included a series of multivariate logistic regression models, controlling for individual-level demographics and body mass index z scores according to mediation analysis procedures for dichotomous outcomes.

RESULTS

Approximately 24% of parents reported their child snored, gasped, or had difficulty breathing at night sometimes, most of the time, or almost always. Regression models with mediation analysis indicate that SHS exposure significantly increased the odds of reporting the child had sleep-related breathing problems, and 18% of this relationship is explained by log serum CRP levels.

CONCLUSIONS

Although the cross-sectional nature of this study limits causality, evidence suggests a relationship exists between SHS exposure, as measured by log hair nicotine and sleep-related breathing problems at night.

Biomarkers of Secondhand Smoke Exposure in Waterpipe Tobacco Venue Employees in Istanbul, Moscow, and Cairo

Background

Most smoke-free legislation to reduce secondhand smoke (SHS) exposure exempts waterpipe (hookah) smoking venues. Few studies have examined SHS exposure in waterpipe venues and their employees.

Methods

We surveyed 276 employees of 46 waterpipe tobacco venues in Istanbul, Moscow, and Cairo. We interviewed venue managers and employees and collected biological samples from employees to measure exhaled carbon monoxide (CO), hair nicotine, saliva cotinine, urine cotinine, urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), and urine 1-hydroxypyrene glucuronide (1-OHPG). We estimated adjusted geometric mean ratios (GMR) of each SHS biomarker by employee characteristics and indoor air SHS measures.

Results

There were 73 nonsmoking employees and 203 current smokers of cigarettes or waterpipe. In nonsmokers, the median (interquartile) range concentrations of SHS biomarkers were 1.1 (0.2, 40.9) µg/g creatinine urine cotinine, 5.5 (2, 15) ng/mL saliva cotinine, 0.95 (0.36, 5.02) ng/mg hair nicotine, 1.48 (0.98, 3.97) pg/mg creatinine urine NNAL, 0.54 (0.25, 0.97) pmol/mg creatinine urine 1-OHPG, and 1.67 (1.33, 2.33) ppm exhaled CO. An 8-hour increase in work hours was associated with higher urine cotinine (GMR: 1.68, 95% CI: 1.20, 2.37) and hair nicotine (GMR: 1.22, 95% CI: 1.05, 1.43). Lighting waterpipes was associated with higher saliva cotinine (GMR: 2.83, 95% CI: 1.05, 7.62).

Conclusions

Nonsmoking employees of waterpipe tobacco venues were exposed to high levels of SHS, including measurable levels of carcinogenic biomarkers (tobacco-specific nitrosamines and PAHs).

Implications

Smoke-free regulation should be extended to waterpipe venues to protect nonsmoking employees and patrons from the adverse health effects of SHS.

Use of electronic nicotine delivery systems by pregnant women II: Hair biomarkers for exposures to nicotine and tobacco-specific nitrosamines

INTRODUCTION

Public awareness of electronic nicotine delivery systems (ENDS) has increased over time, and the perception that ENDS offer a safer alternative to cigarettes may lead some pregnant women to use them to reduce cigarette smoking during pregnancy. No previous studies have used metabolite levels in hair to measure nicotine exposure for ENDS users during pregnancy. We aimed to measure and compare levels of nicotine, cotinine, and tobacco-specific nitrosamines (TSNAs) in hair samples from pregnant women who were current ENDS users, current smokers, and current non-smokers. We also aimed to estimate the association between ENDS use/smoking and smallness for gestational age (SGA).

METHODS

We used hair specimens from pregnant women who were dual users (ENDS and cigarettes), smokers, and non-smokers from a prospective cohort study to estimate exposure to nicotine, cotinine, and TSNAs. The exposure biomarkers and self-reports of smoking and ENDS use were used in log-binomial regression models to estimate risk ratios (RRs) for SGA among offspring.

RESULTS

Nicotine concentrations for pregnant dual users were not significantly different from those for smokers (11.0 and 10.6 ng/mg hair, respectively; p=0.58). Similarly, levels of cotinine, and TSNAs for pregnant dual users were not lower than those for smokers. The RR for SGA was similar for dual users and smokers relative to nonsmokers, (RR=3.5, 95% CI: 0.8-14.8) and (RR=3.3, 95% CI: 0.9-11.6), respectively. Using self-reports confirmed by hair nicotine, the RR values for dual ENDS users and smokers were 8.3 (95% CI: 1.0-69.1) and 7.3 (95% CI:1.0-59.0), respectively.

CONCLUSIONS

We did not observe lower levels of nicotine, cotinine, and TSNAs for current dual users compared to smokers during pregnancy. The risk of SGA for offspring of pregnant dual users was similar to that for offspring of pregnant smokers. Future studies are needed to further estimate the magnitude of the association between ENDS use and smallness for gestational age.

Assessing pediatric tobacco exposure using parent report: comparison with hair nicotine

INTRODUCTION

The purpose of this study was to examine the relationships between screening questions for secondhand smoke (SHS) exposure and biomarker results using hair nicotine levels. Our ultimate goal was to develop sensitive and valid screening tools in pediatric clinical settings for SHS exposure.

METHODS

Investigators developed a core set of questions regarding exposure. Data from two separate ongoing studies of well children and those with bronchopulmonary dysplasia (BPD) were used to assess the concordance between responses and hair nicotine levels. Sensitivity, a positive predictive value, and accuracy were examined.

RESULTS

There was no single question with similar sensitivity in both populations. The question with the highest positive predictive value (90.8% well-cohort and 84.6% BPD cohort) for both the groups was whether the child had been exposed to in-home smoking in the last 7 days. The question with the highest accuracy for both groups was the number of smokers at home (0 vs ≥ 1), with an accuracy of 72.4% for well children and 79.0% for the BPD cohort.

CONCLUSIONS

There was a wide variability in the performance of specific questions. These data demonstrate that a "one-size-fits-all" approach to screening for secondhand tobacco smoke exposure may not be appropriate for all pediatric populations.

Maternal exposure to PM2.5 in south Texas, a pilot study

In this study, we characterized personal exposure to fine particulate matter (PM_2.5), black carbon (BC), and nicotine in pregnant women in Hidalgo County, where the hospitalization rates of childhood asthma are the highest in the state of Texas. The measurements were conducted over three non-consecutive sampling days for 17 participants in their third trimester. Measurements were partitioned into four microenvironments, i.e., Residential, Vehicular, Commercial, and Other, on the basis of GPS coordinates and temperature and humidity measurements. The daily average PM_2.5 mass concentration was 24.2 (standard deviation=22.0) μg/m³, with the highest daily mass concentration reaching 126.0μg/m³. The daily average BC concentration was 1.44 (SD=0.82) μg/m³, ranging from 0.5 to 5.4μg/m³. Hair nicotine concentrations were all near the detection level (i.e., 49.2pg/mg), indicating that the participants were not routinely exposed to tobacco smoke. The Residential microenvironment contributed dominantly to the mass concentration since the participants chiefly remained at home and cooking activities contributed significantly to the total PM_2.5. When compared to an ambient monitoring station, the person-specific PM_2.5 was frequently more than double the ambient measurement (10.4μg/m³ overall), revealing that even in regions where ambient concentrations are below national standards, individuals may be still be exposed to elevated PM_2.5 mass concentrations.

Nicotine cut-off value in human hair as a tool to distinguish active from passive smokers: A cross-sectional study in Japanese men

BACKGROUND

Nicotine concentration in hair is a useful marker of tobacco exposure. Detection of nicotine in the hair of non-smokers indicates passive smoking. Accurate measurement of nicotine among active and passive smokers can help in smoking cessation programs or programs designed to prevent secondhand smoke exposure.

OBJECTIVE

To establish, using high-performance liquid chromatography-ultraviolet detection (HPLC/UV), a hair nicotine cut-off value to distinguish active from passive smokers.

METHODS

Hair samples were collected from randomly chosen Japanese men (n= 192) between 2009 and 2011. Nicotine and cotinine levels in hair were measured using HPLC/UV with column-switching. T-tests and chi-square tests were performed to compare active and passive smokers, while receiver operating characteristic curves were used to evaluate the effectiveness of the cut-off value.

RESULTS

There were 69 active smokers and 123 passive smokers. The nicotine and cotinine concentrations in hair were significantly higher in active than in passive smokers (p< 0.01). The area under the curve for nicotine was 0.92. A hair nicotine cut-off value of 5.68 ng/mg, with a sensitivity of 94.2% and specificity of 87.0%, was identified as the optimal cut-off value for separating active from passive smokers.

CONCLUSION

Nicotine and cotinine concentrations in hair clearly distinguished active from passive smokers.

Higher hair nicotine level in children compared to mother living with smoking father in Malaysia

OBJECTIVES

The objectives of this study are to determine parental and children's hair nicotine levels, their relationships as well as to investigate the association of smoking status of the fathers with mothers' and children's hair nicotine.

METHODS

A cross-sectional study design was conducted among 124 families who were participants of the Universiti Sains Malaysia Pregnancy Cohort Study. Both parents with their 2 years old children joined this study. A total of 92 hair samples of fathers, 124 hair samples of mothers and 111 hair samples of children were collected and analyzed by gas chromatography-mass spectrometry.

RESULTS

Of total, 52.4 % of the fathers reported smoking. None of the mothers were smokers. Hair nicotine levels of fathers were found to be significantly correlated with mothers (r = 0.233, p = 0.026) and children (r = 0.508, p < 0.001). Children living with smoking fathers had significantly higher median hair nicotine level compared to the children of non-smoking fathers (6.08 vs 0.22 ng/mg, p = 0.046). However, this association was not seen in the mothers. Quantile regression showed significant association between fathers' and children's hair nicotine.

CONCLUSION

There is a positive relationship between fathers' hair nicotine with mother's and children's hair nicotine. Living with smoking fathers can contribute to higher hair nicotine levels in children but not in mothers.

Recent advances in MS methods for nicotine and metabolite analysis in human matrices: clinical perspectives

Tobacco smoking is a major global health issue and represents the leading cause of preventable death in the developed countries. Nicotine is a major alkaloid found in tobacco products and its detection with its metabolites in human matrices is generally used for assessing tobacco consumption and second hand exposure. Several analytical techniques have been developed for the detection of nicotine and its metabolites, and MS coupled with chromatography is considered the standard reference method because of its superior sensitivity and specificity. In this work, we reviewed nicotine metabolism, clinical MS and the latest (2009-2014) development of MS-based techniques for measurement of nicotine and metabolites in human matrices. Appropriate biomarker and matrix selection are also critically discussed.

Caspase-12 silencing attenuates inhibitory effects of cigarette smoke extract on NOD1 signaling and hBDs expression in human oral mucosal epithelial cells

Cigarette smoke exposure is associated with increased risk of various diseases. Epithelial cells-mediated innate immune responses to infectious pathogens are compromised by cigarette smoke. Although many studies have established that cigarette smoke exposure affects the expression of Toll-liked receptor (TLR), it remains unknown whether the nucleotide-binding oligomerization domain-containing protein 1 (NOD1) expression is affected by cigarette smoke exposure. In the study, we investigated effects of cigarette smoke extract (CSE) on NOD1 signaling in an immortalized human oral mucosal epithelial (Leuk-1) cell line. We first found that CSE inhibited NOD1 expression in a dose-dependent manner. Moreover, CSE modulated the expression of other crucial molecules in NOD1 signaling and human β defensin (hBD) 1, 2 and 3. We found that RNA interference-induced Caspase-12 silencing increased NOD1 and phospho-NF-κB (p-NF-κB) expression and down-regulated RIP2 expression. The inhibitory effects of CSE on NOD1 signaling can be attenuated partially through Caspase-12 silencing. Intriguingly, Caspase-12 silencing abrogated inhibitory effects of CSE on hBD1, 3 expression and augmented induced effect of CSE on hBD2 expression. Caspase-12 could play a vital role in the inhibitory effects of cigarette smoke on NOD1 signaling and hBDs expression in oral mucosal epithelial cells.

Utility and cutoff value of hair nicotine as a biomarker of long-term tobacco smoke exposure, compared to salivary cotinine

While hair samples are easier to collect and less expensive to store and transport than biological fluids, and hair nicotine characterizes tobacco exposure over a longer time period than blood or urine cotinine, information on its utility, compared with salivary cotinine, is still limited. We conducted a cross-sectional study with 289 participants (107 active smokers, 105 passive smokers with self-reported secondhand smoke (SHS) exposure, and 77 non-smokers with no SHS exposure) in Baltimore (Maryland, USA). A subset of the study participants (n = 52) were followed longitudinally over a two-month interval. Median baseline hair nicotine concentrations for active, passive and non-smokers were 16.2, 0.36, and 0.23 ng/mg, respectively, while those for salivary cotinine were 181.0, 0.27, and 0.27 ng/mL, respectively. Hair nicotine concentrations for 10% of passive or non-smokers were higher than the 25th percentile value for active smokers while all corresponding salivary cotinine concentrations for them were lower than the value for active smokers. This study showed that hair nicotine concentration values could be used to distinguish active or heavy passive adult smokers from non-SHS exposed non-smokers. Our results indicate that hair nicotine is a useful biomarker for the assessment of long-term exposure to tobacco smoke.

Occupational secondhand smoke is the main determinant of hair nicotine concentrations in bar and restaurant workers

OBJECTIVE

To evaluate the relative contribution of occupational vs. non-occupational secondhand tobacco smoke exposure to overall hair nicotine concentrations in non-smoking bar and restaurant employees.

METHOD

We recruited 76 non-smoking employees from venues that allowed smoking (n=9), had mixed policies (smoking and non-smoking areas, n=13) or were smoke-free (n=2) between April and August 2008 in Santiago, Chile. Employees used personal air nicotine samplers during working and non-working hours for a 24-h period to assess occupational vs. non-occupational secondhand tobacco smoke exposure and hair nicotine concentrations to assess overall secondhand tobacco smoke exposure.

RESULTS

Median hair nicotine concentrations were 1.5 ng/mg, interquartile range (IQR) 0.7 to 5.2 ng/mg. Time weighted average personal air nicotine concentrations were higher during working hours (median 9.7, IQR 3.3-25.4 µg/m(3)) compared to non-working hours (1.7, 1.0-3.1 µg/m(3)). Hair nicotine concentration was best predicted by personal air nicotine concentration at working hours. After adjustment, a 2-fold increase in personal air nicotine concentration in working hours was associated with a 42% increase in hair nicotine concentration (95% confidence interval 14-70%). Hair nicotine concentration was not associated with personal air nicotine concentration during non-working hours (non-occupational exposure).

CONCLUSIONS

Personal air nicotine concentration at working hours was the major determinant of hair nicotine concentrations in non-smoking employees from Santiago, Chile. Secondhand tobacco smoke exposure during working hours is a health hazard for hospitality employees working in venues where smoking is allowed.

Instruments to assess secondhand smoke exposure in large cohorts of never smokers: the smoke scales

The objectives of this study were to: (i) to develop questionnaires that can identify never-smoking children and adults experiencing increased exposure to secondhand smoke (SHS+), (ii) to determine their validity against hair nicotine, and (iii) assess their reliability. A sample of 191 children (85 males; 106 females; 7–18 years) and 95 adult (23 males; 72 females; 18–62 years) never-smokers consented to hair nicotine analysis and answered a large number of questions assessing all sources of SHS. A randomly-selected 30% answered the questions again after 20–30 days. Prevalence of SHS+ in children and adults was 0.52±0.07 and 0.67±0.10, respectively (p<0.05). The Smoke Scale for Children (SS-C) and the Smoke Scale for Adults (SS-A) were developed via factor analysis and included nine questions each. Positivity criteria for SS-C and SS-A via receiver operating characteristics curve analysis were identified at >16.5 and >16, respectively. Significant Kappa agreement (p<0.05) was confirmed when comparing the SS-C and SS-A to hair nicotine concentration. Reliability analyses demonstrated that the SS-C and SS-A scores obtained on two different days are highly correlated (p<0.001) and not significantly different (p>0.05). Area under the curve and McNemar's Chi-square showed no pair-wise differences in sensitivity and specificity at the cutoff point between the two different days for SS-C and SS-A (p>0.05). We conclude that the SS-C and the SS-A represent valid, reliable, practical, and inexpensive instruments to identify children and adult never-smokers exposed to increased SHS. Future research should aim to further increase the validity of the two questionnaires.

Hair Cortisol, Perceived Stress and Dispositional Optimism: A Pilot Study among Adolescents

BACKGROUND

Psychological stress is often associated with poor health-related outcomes. One potential biomarker for chronic stress, hair cortisol, is minimally invasive compared to other cortisol collection techniques. This pilot study examined the relationships between hair cortisol and self-reported perceived stress, stressful life events, depressive symptoms, and dispositional optimism among adolescents.

METHODS

This cross-sectional study comprised of a convenience sample of 27 adolescents (age: M=14.96, SD=1.63) recruited from a Southern California after-school program. Along with demographic and hair characteristics (e.g., hair color, type, etc.), participants completed the Perceived Stress Scale, Stressful Life Events checklist, CES-D (depressive symptoms), and Life Orientation Test (optimism). Hair cortisol was measured by analyzing hair samples approximately 1 cm from the scalp representing one month of cortisol exposure.

RESULTS

Hair cortisol had a significant inverse association with dispositional optimism (r=-0.44, p<0.05). Hair cortisol was not significantly associated with self-reported perceived stress, stressful life events, or depressive symptoms.

CONCLUSION

Assessment of hair cortisol may prove beneficial as an objective measure in research examining chronic stress-related outcomes among adolescents. Resiliency or protective dispositions, such as optimism, merit attention in relation to this biomarker.

Secondhand tobacco smoke: an occupational hazard for smoking and non-smoking bar and nightclub employees

BACKGROUND

In the absence of comprehensive smoking bans in public places, bars and nightclubs have the highest concentrations of secondhand tobacco smoke, posing a serious health risk for workers in these venues.

OBJECTIVE

To assess exposure of bar and nightclub employees to secondhand smoke, including non-smoking and smoking employees.

METHODS

Between 2007 and 2009, the authors recruited approximately 10 venues per city and up to five employees per venue in 24 cities in the Americas, Eastern Europe, Asia and Africa. Air nicotine concentrations were measured for 7 days in 238 venues. To evaluate personal exposure to secondhand smoke, hair nicotine concentrations were also measured for 625 non-smoking and 311 smoking employees (N=936).

RESULTS

Median (IQR) air nicotine concentrations were 3.5 (1.5-8.5) μg/m(3) and 0.2 (0.1-0.7) μg/m(3) in smoking and smoke-free venues, respectively. Median (IQR) hair nicotine concentrations were 6.0 (1.6-16.0) ng/mg and 1.7 (0.5-5.5) ng/mg in smoking and non-smoking employees, respectively. After adjustment for age, sex, education, living with a smoker, hair treatment and region, a twofold increase in air nicotine concentrations was associated with a 30% (95% CI 23% to 38%) increase in hair nicotine concentrations in non-smoking employees and with a 10% (2% to 19%) increase in smoking employees.

CONCLUSIONS

Occupational exposure to secondhand smoke, assessed by air nicotine, resulted in elevated concentrations of hair nicotine among non-smoking and smoking bar and nightclub employees. The high levels of airborne nicotine found in bars and nightclubs and the contribution of this exposure to employee hair nicotine concentrations support the need for legislation measures that ensure complete protection from secondhand smoke in these venues.

Cigarette smoke induces epithelial to mesenchymal transition and increases the metastatic ability of breast cancer cells

Background

Recent epidemiological studies demonstrate that both active and involuntary exposure to tobacco smoke increase the risk of breast cancer. Little is known, however, about the molecular mechanisms by which continuous, long term exposure to tobacco smoke contributes to breast carcinogenesis because most previous studies have focused on short term treatment models. In this work we have set out to investigate the progressive transforming effects of tobacco smoke on non-tumorigenic mammary epithelial cells and breast cancer cells using in vitro and in vivo models of chronic cigarette smoke exposure.

Results

We show that both non-tumorigenic (MCF 10A, MCF-12A) and tumorigenic (MCF7) breast epithelial cells exposed to cigarette smoke acquire mesenchymal properties such as fibroblastoid morphology, increased anchorage-independent growth, and increased motility and invasiveness. Moreover, transplantation experiments in mice demonstrate that treatment with cigarette smoke extract renders MCF 10A cells more capable to survive and colonize the mammary ducts and MCF7 cells more prone to metastasize from a subcutaneous injection site, independent of cigarette smoke effects on the host and stromal environment. The extent of transformation and the resulting phenotype thus appear to be associated with the differentiation state of the cells at the time of exposure. Analysis by flow cytometry showed that treatment with CSE leads to the emergence of a CD44^hi/CD24^low population in MCF 10A cells and of CD44⁺ and CD49f ⁺ MCF7 cells, indicating that cigarette smoke causes the emergence of cell populations bearing markers of self-renewing stem-like cells. The phenotypical alterations induced by cigarette smoke are accompanied by numerous changes in gene expression that are associated with epithelial to mesenchymal transition and tumorigenesis.

Conclusions

Our results indicate that exposure to cigarette smoke leads to a more aggressive and transformed phenotype in human mammary epithelial cells and that the differentiation state of the cell at the time of exposure may be an important determinant in the phenotype of the final transformed state.

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.

Secondhand tobacco smoke exposure and associated factors among college students on campus and in the home: a preliminary study

To explore the prevalence of secondhand tobacco smoke (SHS) exposure of college students at two locations, i.e., on campus and in the home, and to identify factors associated with SHS exposure at each location, a preliminary cross-sectional study was conducted on 1754 nonsmoking students from two universities in Korea. In total, 83.1% were exposed to SHS at least once a week on campus or at home; the average SHS exposure was 3.4 times per week. Specifically, 79.7% and 23.5% were exposed to SHS on campus and in the home, respectively. On campus, SHS exposure was significantly more prevalent in freshmen and sophomore students. In the home, SHS exposure was significantly more prevalent among females, those with smokers in their families, and those who rated their health as poor. SHS exposure was common among nonsmoking college students, with more than two-thirds exposed on campus. The prevalence of SHS exposure was greater on campus than in the home; the factors associated with SHS exposure were location-specific.

Recent contributions of air- and biomarkers to the control of secondhand smoke (SHS): a review

Since the publication of the US Surgeon General Reports in 1996 and 2006 and the report of the California Environmental Protection Agency in 1999, many reports have appeared on the contribution of air and biomarkers to different facets of the secondhand smoke (SHS) issue, which are the targets of this review. These recent studies have allowed earlier epidemiological surveys to be biologically validated, and their plausibility demonstrated, quantified the levels of exposure to SHS before the bans in various environments, showed the deficiencies of mechanical control methods and of partial bans and the frequently correct implementation of the efficient total bans. More stringent regulation remains necessary in the public domain (workplaces, hospitality venues, transport sector, etc.) in many countries. Personal voluntary protection efforts against SHS are also needed in the private domain (homes, private cars). The effects of SHS on the cardiovascular, respiratory and neuropsychic systems, on pregnancy and fertility, on cancers and on SHS genotoxicity are confirmed through experimental human studies and through the relationship between markers and prevalence of disease or of markers of disease risk.

Exposure to particulate matters (PM2.5) and airborne nicotine in computer game rooms after implementation of smoke-free legislation in South Korea

INTRODUCTION

In South Korea, computer game rooms are subject to regulations mandating a designated nonsmoking area pursuant to Article 7 of the Enforcement Rules of the National Health Promotion Act; nonsmoking areas must be enclosed on all sides by solid and impermeable partitions.

METHODS

Using PM(2.5) monitors (SidePak AM510) and airborne nicotine monitors, we measured concentrations in smoking and nonsmoking areas to examine whether separation of the nonsmoking areas as currently practiced is a viable way to protect the nonsmoking area from secondhand smoke exposure. Convenient samplings were conducted at 28 computer game rooms randomly selected from 14 districts in Seoul, South Korea between August and September 2009.

RESULTS

The medians (interquartile range) of PM(2.5) concentrations in smoking and nonsmoking areas were 69.3 μg/m(3) (34.5-116.5 μg/m(3)) and 34 μg/m(3) (15.0-57.0 μg/m(3)), while those of airborne nicotine were 0.41 μg/m(3) (0.25-0.69 μg/m(3)) and 0.12 μg/m(3) (0.06-0.16 μg/m(3)), respectively. Concentrations of airborne nicotine and PM(2.5) in nonsmoking areas were substantially positively associated with those in smoking areas. The Spearman correlation coefficients for them were 0.68 (p = .02) and 0.1 (p = 0.7), respectively. According to our modeling result, unit increase of airborne nicotine concentration in a smoking area contributed to 7 (95% CI = 2.5-19.8) times increase of the concentration in the adjacent nonsmoking area after controlling for the degree of partition left closed and the indoor space volume.

CONCLUSIONS

Our study thus provides evidence for the introduction of more rigorous policy initiatives aimed at encouraging a complete smoking ban in such venues.

Secondhand tobacco smoke exposure in selected public places (PM2.5 and air nicotine) and non-smoking employees (hair nicotine) in Ghana

BACKGROUND

Secondhand tobacco smoke (SHS) exposure is a global public health problem. Ghana currently has no legislation to prevent smoking in public places. To provide data on SHS levels in hospitality venues in Ghana the authors measured (1) airborne particulate matter <2.5 μm (PM(2.5)) and nicotine concentrations and (2) hair nicotine concentrations in non-smoking employees. Quantifying SHS exposure will provide evidence needed to develop tobacco control legislation.

METHOD

PM(2.5) was measured for 30 min in 75 smoking and 13 non-smoking venues. Air nicotine concentrations were measured for 7 days in 8 smoking and 2 non-smoking venues. Additionally, 63 non-smoking employees provided hair samples for nicotine analysis.

RESULT

Compared to non-smoking venues, smoking venues had markedly elevated PM(2.5) (median 553 [IQR 259-1038] vs 16.0 [14.0-17.0]μg/m(3)) and air nicotine (1.83 [0.91-4.25] vs 0.03 [0.02-0.04]μg/m(3)) concentrations. Hair nicotine concentrations were also higher in non-smoking employees working in smoking venues (median 2.49 [0.46-6.84] ng/mg) compared to those working in non-smoking venues (median 0.16 [0.08-0.79]ng/mg). Hair nicotine concentrations correlated with self-reported hours of SHS exposure (r=0.35), indoor air PM(2.5) concentrations (r=0.47) and air nicotine concentrations (r=0.63).

CONCLUSION

SHS levels were unacceptably high in public places in Ghana where smoking is allowed, despite a relatively low-smoking prevalence in the country. This is one of the first studies to ascertain SHS and hair nicotine in Africa. Levels were comparable to those measured in American, Asian and European countries without or before smoking bans. Implementing a comprehensive smoke-free legislation that protects workers and customers from exposure to secondhand smoke is urgently needed in Ghana.

Secondhand tobacco smoke in bars and restaurants in Santiago, Chile: evaluation of partial smoking ban legislation in public places

Objective

To compare air nicotine concentrations according to the smoking policy selected by bars/restaurants in Santiago, Chile before and after the enactment of partial smoking ban legislation in 2007 (establishments could be smoke free, have segregated (mixed) smoking and non-smoking areas, or allow smoking in all areas).

Methods

The study measured air nicotine concentrations over 7 days to characterise secondhand smoke exposure in 30 bars/restaurants in 2008. Owner/manager interviews and physical inspections were conducted.

Results

Median IQR air nicotine concentrations measured in all venues were 4.38 (0.61–13.62) μg/m³. Air nicotine concentrations were higher in bars (median 7.22, IQR 2.48–15.64 μg/m³) compared to restaurants (1.12, 0.15–9.22 μg/m³). By smoking status, nicotine concentrations were higher in smoking venues (13.46, 5.31–16.87 μg/m³), followed by smoking areas in mixed venues (9.22, 5.09–14.90 μg/m³) and non-smoking areas in mixed venues (0.99, 0.19–1.27 μg/m³). Air nicotine concentrations were markedly lower in smoke-free venues (0.12, 0.11–0.46 μg/m³). After adjustment for differences in volume and ventilation, air nicotine concentrations were 3.2, 35.5 and 56.2 times higher in non-smoking areas in mixed venues, smoking areas in mixed venues and smoking venues, respectively, compared to smoke-free venues.

Conclusions

Exposure to secondhand smoke remains high in bars and restaurants in Santiago, Chile. These findings demonstrate that the partial smoking ban legislation enacted in Chile in 2007 provides no protection to employees working in those venues. Enacting a comprehensive smoke-free legislation which protects all people from exposure to secondhand smoke in all public places and workplaces is urgently needed.

Excessive exposure to secondhand tobacco smoke among hospitality workers in Kyrgyzstan

The aim of this study was to assess the levels of secondhand smoke (SHS) exposure of men and women in public places in Kyrgyzstan. This cross-sectional study involved 10 bars and restaurants in Bishkek the capital city of Kyrgyzstan. Smoking was allowed in all establishments. Median (interquartile range) air nicotine concentrations were 6.82 (2.89, 8.86) microg/m(3). Employees were asked about their smoking history and exposure to SHS at work. Employees were exposed to SHS for mean (SD) 13.5 (3.6) hours a day and 5.8 (1.4) days a week. Women were exposed to more hours of SHS at work compared to men. Hospitality workers are exposed to excessive amounts of SHS from customers. Legislation to ban smoking in public places including bars and restaurants is urgently needed to protect workers and patrons from the harmful effects of SHS.