Biomarkers of Exposure among U.S. Adult Cigar Smokers: Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013-2014)

Biomarkers of Toxic Exposure and Oxidative Stress Among U.S. Adult Users of Premium Cigar Versus Other Cigar Subtypes: 2013-2019

INTRODUCTION

Cigars are currently the second-highest-used combustible tobacco product among U.S. adults, but knowledge about health effects of premium cigars versus other cigar subtype use is limited.

AIMS AND METHODS

This study analyzed the biospecimen data (n = 31 875) from Waves 1-5 of the Population Assessment of Tobacco and Health Study, collected during 2013-2019. Multivariable generalized estimation equations, accounting for within-person clustering, were conducted to examine differences in urine biomarkers of exposure (BOE) from five classes of harmful and potentially harmful constituents along with a biomarker of oxidative stress (urine 8-isoprostane) among exclusive users of premium cigars versus other exclusive cigar subtypes (ie, non-premium large cigars, cigarillos, and filtered cigars), cigarettes, and non-tobacco users.

RESULTS

In comparison to non-tobacco users, exclusive premium cigar users had higher geometric mean concentrations of the nicotine metabolite cotinine (5.8 vs. 0.5ng/mg, p < .0001), tobacco-specific nitrosamine (TSNA) (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL): 7.8 vs. 1.3pg/mg, p < .0001), and volatile organic compound (VOC) (N-Acetyl-S-(2-cyanoethyl)-L-cysteine (CYMA, acrylonitrile): 4.7 vs. 1.6ng/mg, p < .0001). Exclusive premium cigar users were less likely to be daily users than other tobacco user groups and had comparable BOEs with exclusive non-premium large cigar users but generally lower BOEs than exclusive cigarillo, filtered cigar, and cigarette smokers. Daily exclusive premium cigar users had similar nicotine and TSNA exposure but lower exposure to polycyclic aromatic hydrocarbons and volatile organic compounds than exclusive cigarillo and filtered cigar users.

CONCLUSIONS

Premium cigar use exhibits different exposure to toxicants from other cigar subtype users. Regulations of premium cigars need to formalize product definition and take the population's health effects into consideration.

IMPLICATIONS

This population study provides important information on BOE and potential harm with premium cigar use and its potential health effects. At present, premium cigars appear to pose a relatively low overall population health risk due to low frequency of use. However, future regulation of other tobacco products might change the landscape of premium cigar use and alter the overall health impact.

Associations between biomarkers of nicotine/tobacco exposure and respiratory symptoms among adults who exclusively smoke cigarettes in the U.S.: Findings from the PATH Study Waves 1-4 (2013-2017)

Significance

Determining if tobacco-related biomarkers of exposure (BOE) are associated with respiratory symptoms is an important public health tool that can be used to evaluate the potential harm of different tobacco products.

Methods

Adult data from people who exclusively smoked cigarettes (N = 2,438) in Waves 1-4 (2013-2017) of the Population Assessment of Tobacco and Health Study were stacked to examine associations between baseline and follow-up within wave pairs (W1-W2, W2-W3, W3-W4). Weighted generalized estimating equation models were used to evaluate associations between biomarkers of nicotine, tobacco-specific nitrosamines, acrolein, acrylonitrile, cadmium, and lead at baseline/follow-up and respiratory symptom(s) (wheezing/whistling in the chest, wheezing during exercise, and/or dry cough in the past 12 months) at follow-up.

Results

Higher acrolein metabolite (CEMA) levels at follow-up were associated with increased odds of respiratory symptoms at follow-up for people who exclusively smoked cigarettes (aOR = 1.34; 95% CI = 1.06, 1.70), including when limited to those without a diagnosed respiratory disease (aOR = 1.46; 95% CI = 1.12, 1.90) and those who smoked daily (aOR = 1.40; 95% CI = 1.06, 1.84). Higher cadmium levels at baseline (while controlling for follow-up levels) were associated with reduced odds of respiratory symptoms at follow-up (aOR = 0.80; 95% CI = 0.65, 0.98) among people who exclusively smoked cigarettes without a respiratory disease. There were no significant associations between baseline/follow-up BOE and follow-up respiratory symptoms for people who smoked cigarettes non-daily.

Conclusions

This research supports measuring biomarkers of acrolein, such as CEMA, as a potential intermediate measurement for increased respiratory symptom development. Measuring these biomarkers could help alleviate the clinical burden of respiratory disease.

The Associations of Trans-3'-Hydroxy Cotinine, Cotinine, and the Nicotine Metabolite Ratio in Pediatric Patients with Tobacco Smoke Exposure

(1) Background: Trans-3'-hydroxy cotinine (3HC) and cotinine (COT) are tobacco smoke exposure (TSE) biomarkers and the 3HC/COT ratio is a marker of CYP2A6 activity, an enzyme which metabolizes nicotine. The primary objective was to assess the associations of these TSE biomarkers with sociodemographics and TSE patterns in children who lived with ≥1 smoker. (2) Methods: A convenience sample of 288 children (mean age (SD) = 6.42 (4.8) years) was recruited. Multiple linear regression models were built to assess associations of sociodemographics and TSE patterns with urinary biomarker response variables: (1) 3HC, (2) COT, (3) 3HC+COT sum, and (4) 3HC/COT ratio. (3) Results: All children had detectable 3HC (Geometric Mean [GeoM] = 32.03 ng/mL, 95%CI = 26.97, 38.04) and COT (GeoM = 10.24 ng/mL, 95%CI = 8.82, 11.89). Children with higher cumulative TSE had higher 3HC and COT (β^ = 0.03, 95%CI = 0.01, 0.06, p = 0.015 and β^ = 0.03, 95%CI = 0.01, 0.05, p = 0.013, respectively). Highest 3HC+COT sum levels were in children who were Black (β^ = 0.60, 95%CI = 0.04, 1.17, p = 0.039) and who had higher cumulative TSE (β^ = 0.03, 95%CI = 0.01, 0.06, p = 0.015). Lowest 3HC/COT ratios were in children who were Black (β^ = -0.42, 95%CI = -0.78, -0.07, p = 0.021) and female (β^ = -0.32, 95%CI = -0.62, -0.01, p = 0.044). (4) Conclusion: Results indicate that there are racial and age-related differences in TSE, most likely due to slower nicotine metabolism in non-Hispanic Black children and in younger children.

Public health impact of a US ban on menthol in cigarettes and cigars: a simulation study

INTRODUCTION

The US Food and Drug Administration most recently announced its intention to ban menthol cigarettes and cigars nationwide in April 2021. Implementation of the ban will require evidence that it would improve public health. This paper simulates the potential public health impact of a ban on menthol in cigarettes and cigars through its impacts on smoking initiation, smoking cessation and switching to nicotine vaping products (NVPs).

METHODS

After calibrating an established US simulation model to reflect recent use trends in cigarette and NVP use, we extended the model to incorporate menthol and non-menthol cigarette use under a status quo scenario. Applying estimates from a recent expert elicitation on the behavioural impacts of a menthol ban, we developed a menthol ban scenario with the ban starting in 2021. We estimated the public health impact as the difference between smoking and vaping-attributable deaths and life-years lost in the status quo scenario and the menthol ban scenario from 2021 to 2060.

RESULTS

As a result of the ban, overall smoking was estimated to decline by 15% as early as 2026 due to menthol smokers quitting both NVP and combustible use or switching to NVPs. These transitions are projected to reduce cumulative smoking and vaping-attributable deaths from 2021 to 2060 by 5% (650 000 in total) and reduce life-years lost by 8.8% (11.3 million). Sensitivity analyses showed appreciable public health benefits across different parameter specifications.

CONCLUSIONS AND RELEVANCE

Our findings strongly support the implementation of a ban on menthol in cigarettes and cigars.

Mouth Level Intake of Nicotine from Three Brands of Little Filtered Cigars with Widely Differing Product Characteristics Among Adult Consumers

Little filtered cigars are tobacco products with many cigarette-like characteristics. However, despite cigars falling under the U.S. Food and Drug Administration regulatory authority, characterizing flavors, which are still allowed in little filtered cigars, and filter design may influence how people use the products and the resulting exposure to harmful and potentially harmful constituents. We estimated nicotine mouth level intake (MLI) from analyses of little cigar filter butt solanesol levels, brand characteristics, carbon monoxide boost, and puff volume in 48 dual cigarette/cigar users during two repeat bouts of ad lib smoking of three little filtered cigar brands. Mean nicotine MLI for the three brands was significantly different with Swisher Sweets (0.1% ventilation) Cherry at 1.20 mg nicotine, Cheyenne Menthol (1.5%) at 0.63 mg, and Santa Fe unflavored (49%) at 0.94 mg. The association between nicotine MLI and puff volume was the same between Cheyenne Menthol and Santa Fe unflavored. However, these were different from Swisher Sweets Cherry. At least five main factors─flavor, ventilation, filter design, nicotine delivery related to tar, and user puff volume─may directly or indirectly impact MLI and its association with other measures. We found that users of little filtered cigars that have different filter ventilation and flavor draw dissimilar amounts of nicotine from the product, which may be accompanied by differences in exposure to other harmful smoke constituents.

Study of urinary mercapturic acids as biomarkers of human acrylonitrile exposure

Exposure to the vinyl monomer acrylonitrile (AN) is primarily occupational. AN is also found in cigarette smoke. AN can be detoxified to form N-acetyl-S-(2-cyanoethyl)-cysteine (CEMA) or activated to 2-cyanoethylene oxide (CEO) and detoxified to form N-acetyl-S-(1-cyano-2-hydroxyethyl)-cysteine (CHEMA) and N-acetyl-S-(2-hydroxyethyl)-cysteine (HEMA). These urinary mercapturic acids (MAs) are considered to be potential biomarkers of AN exposure. This study assessed personal AN exposure, urinary MAs (CEMA, CHEMA, and HEMA), and cotinine (a biomarker of cigarette smoke) in 80 AN-exposed and 23 non-exposed factory workers from urine samples provided before and after work shifts. Unambiguous linear correlations were observed between levels of urinary CEMA and CHEMA with personal AN exposures, indicating their potential as chemically-specific biomarkers for AN exposures. AN exposure was the dominant factor in MA formation for AN-exposed workers, whereas urinary cotinine used as a biomarker showed that cigarette smoke exposure was the primary factor for non-exposed workers. The CHEMA/CEMA and (CHEMA+HEMA)/CEMA ratios in this human study differ from those in similar studies of AN-treated rats and mice in literature, suggesting a possible dose- and species-dependent effect in AN metabolic activation and detoxification.

Internalizing problems are associated with initiation and past 30-Day use of flavored tobacco products

OBJECTIVE

Tobacco use remains disproportionately common among adults with internalizing problems. The rising prevalence of flavored tobacco use among this population may be a contributing factor. Using data from Wave 4 of the Population Assessment of Tobacco and Health Study, this study examined differences across adult ever tobacco users by severity of internalizing problems, in initiation of tobacco use with a flavored product and past 30-day (current) flavored tobacco use (n = 27,425). Severity of internalizing problems was measured using the Global Appraisal of Individual Needs-Short Screener Internalizing Disorder Screener. Tobacco use variables included initiation with or current use of a flavored product, assessed separately for each product. Weighted chi-square tests and multivariable modified Poisson regression models were used to examine the associations between severity of internalizing problems and each outcome.

RESULTS

Controlling for covariates, ever users with severe internalizing problems were more likely to have initiated with flavors for cigarettes (adjusted prevalence ratio [aPR]: 1.16, 95% confidence interval [CI]: 1.09,1.24), cigarillos (aPR: 1.09, 95% CI: 1.03, 1.16), electronic nicotine products (aPR: 1.08, 95% CI: 1.03, 1.13) and smokeless tobacco (aPR: 1.15, 95% CI: 1.04, 1.27), relative to those with low internalizing problems. Ever users with severe internalizing problems were more likely to currently use a flavored tobacco product for cigarettes (aPR: 1.15, 95% CI: 1.07, 1.24) and cigarillos (aPR: 1.15, 95% CI: 1.04, 1.28).

CONCLUSIONS

Flavored tobacco use seems disproportionately common among tobacco users with severe internalizing problems, across a variety of measures.

Age of Initiation of Dual Tobacco Use and Binge Drinking among Youth (12-17 Years Old): Findings from the Population Assessment of Tobacco and Health (PATH) Study

Earlier exposure to binge drinking and tobacco use is associated with higher odds of substance use disorders. Using national youth data from the PATH study, we prospectively estimate the age of initiating past 30-day use of (1) cigarettes, e-cigarettes, and binge drinking, and (2) cigarettes, cigarillos, and binge drinking. Cox proportional hazard models were used to estimate differences in the age of initiation by sex, race/ethnicity, and previous use of other tobacco products. By age 21, 4.4% (95% CI: 3.7-5.2) and 2.0% (95% CI: 1.2-2.8) of youth reported initiation of past 30-day use outcomes (1) and (2), respectively. After controlling for sex and previous use of other tobacco products, statistically significant differences in the age of initiation by race/ethnicity were found for each outcome: Hispanic and non-Hispanic Black youth were less likely than non-Hispanic White youth to initiate past 30-day use of both outcomes (1) and (2) at earlier ages. Although the initiation of both outcomes remained relatively low by age 21, these incidences represent 1.56 million and 700,000 youth, respectively. This study provides the public with evidence to identify the particular ages at which education campaigns may be most effective to prevent youth from initiating these three substances. Further research is needed to estimate the age of initiation of other dual tobacco use patterns with binge drinking.

Assessment of Exclusive, Dual, and Polytobacco E-Cigarette Use and COVID-19 Outcomes Among College Students

Purpose

This study examined current (past 30-day) dual- and polytobacco use patterns and COVID-19 symptomatology, testing, and diagnosis status among college student electronic cigarette (e-cigarette) users.

Design

Cross-sectional online questionnaire administered during October–December 2020.

Setting

Four large, U.S. public universities in geographically diverse locations.

Sample

College students (N=756) ages 18–24 who reported current e-cigarette use.

Measures

Current use of e-cigarettes, combustible cigarettes, and cigars, and self-reported COVID-19 symptomatology, testing, and diagnosis status were measured.

Analysis

Multivariable logistic regression models accounting for students’ demographics, university site, fraternity/sorority membership, and current residence.

Results

Over half (53.6%) of students were exclusive e-cigarette users, 20.4% were dual e-cigarette and combustible cigarette users, 4.6% were dual e-cigarette and cigar users, and 21.4% were poly users of e-cigarettes, combustible cigarettes, and cigars. Compared to exclusive e-cigarette users, dual users of e-cigarettes and combustible cigarettes (AOR=2.12, 95%CI=1.05–4.27) and poly users of e-cigarettes, combustible cigarettes, and cigars (AOR=3.70, 95%CI=1.78–7.70) had increased odds of COVID-19 symptomatology, even when accounting for covariates. While current tobacco use groups did not differ based on COVID-19 testing, polytobacco users had significantly increased odds (AOR=2.16, 95%CI=1.11–4.20) of having received a positive COVID-19 diagnosis.

Conclusion

Given use of two or more tobacco products increased COVID-19-related risks, results underscore the need to prevent dual- and polytobacco use behaviors in college student e-cigarette users.

Social Determinants of Cigarette Smoking among American Women during Pregnancy

Educational attainment is among the most substantial protective factors against cigarette smoking, including during pregnancy. Although Minorities’ Diminished Returns (MDRs) of educational attainment, defined as weaker protective effect of education for racial and ethnic minority groups compared to Non-Hispanic Whites, has been demonstrated in previous studies; such MDRs are not tested for cigarette smoking during pregnancy. To better understand the relevance of MDRs to tobacco use during pregnancy, this study had three aims: firstly, to investigate the association between educational attainment and cigarette smoking in pregnant women; secondly, to compare racial and ethnic groups for the association between educational attainment and cigarette smoking; and thirdly, to explore the mediating effect of poverty status on such MDRs, among American adults during pregnancy. This cross-sectional study explored a nationally representative sample of pregnant American women (n = 338), which was taken from the Population Assessment of Tobacco and Health (PATH; 2013). Current smoking was the outcome. Educational attainment was the independent variable. Region and age were the covariates. Poverty status was the mediator. Race and ethnicity were the effect modifiers. Overall, a higher level of educational attainment (OR = 0.54, p < 0.05) was associated with lower odds of current smoking among pregnant women. Race (OR = 2.04, p < 0.05) and ethnicity (OR = 2.12, p < 0.05) both showed significant interactions with educational attainment on smoking, suggesting that the protective effect of educational attainment against smoking during pregnancy is smaller for Blacks and Hispanics than Non-Hispanic Whites. Poverty status fully mediated the above interactions. In the United States, highly educated pregnant Black and Hispanic women remain at higher risk of smoking cigarettes, possibly because they are more likely to live in poverty, compared to their White counterparts. The results suggest the role that labor market discrimination has in explaining lower returns of educational attainment in terms of less cigarette smoking by racial and ethnic minority pregnant women.

Hand Nicotine and Cotinine In Children Exposed to Cigars: A Pilot Study

Objectives

Past research has not examined secondhand and thirdhand smoke (THS) exposure in children of cigar smokers. We examined hand nicotine and cotinine levels in children of cigar smokers to explore the contribution of cigar smoke to tobacco smoke exposure (TSE).

Methods

Participants were children (N = 24; mean (SD) age = 6.5 (3.6) years) whose parents smoked cigars only or poly-used cigars and/or cigarettes. Primary outcomes were hand nicotine and urinary cotinine levels.

Results

All children had detectable hand nicotine (range: 7.6-312.5ng/wipe) and cotinine (range: 0.3-100.3ng/ml). Positive correlations were found between hand nicotine and cotinine (r = 0.693, p = .001), hand nicotine and parents who also smoked cigarettes (r = 0.407, p = .048), and hand nicotine and number of smokers around the child (r = 0.436, p = .03). Hand nicotine (r = -0.464, p = .02), but not cotinine (r = -0.266, p = .26), was negatively correlated with child age. Multiple regression results indicated a positive association between hand nicotine and cotinine (p = .002; semi-partial r² = 0.415), irrespective of child age.

Conclusions

The significant association of hand nicotine with urinary cotinine suggests that THS pollution should be assessed in evaluating children's overall TSE to cigars and other tobacco products, and hand nicotine may be a proxy for overall TSE. Younger children may have increased THS pollutant uptake.

Urinary Cotinine and Cotinine + Trans-3'-Hydroxycotinine (TNE-2) Cut-points for Distinguishing Tobacco Use from Nonuse in the United States: PATH Study (2013-2014)

BACKGROUND

Determine the overall, sex-, and racially/ethnically-appropriate population-level cotinine and total nicotine equivalents (TNE-2, the molar sum of the two major nicotine metabolites) cut-points to distinguish tobacco users from nonusers across multiple definitions of use (e.g., exclusive vs. polytobacco, and daily vs. non-daily).

METHODS

Using Wave 1 (2013-2014) of the U.S. Population Assessment of Tobacco and Health (PATH) Study, we conducted weighted Receiver Operating Characteristic (ROC) analysis to determine the optimal urinary cotinine and TNE-2 cut-points, stratified by sex and race/ethnicity.

RESULTS

For past 30-day exclusive cigarette users, the cotinine cut-point that distinguished them from nonusers was 40.5 ng/mL, with considerable variation by sex (male: 22.2 ng/mL; female: 43.1 ng/mL) and between racial/ethnic groups (non-Hispanic other: 5.2 ng/mL; non-Hispanic black: 297.0 ng/mL). A similar, but attenuated, pattern emerged when assessing polytobacco cigarette users (overall cut-point = 39.1 ng/mL, range = 5.5 ng/mL-80.4 ng/mL) and any tobacco users (overall cut-point = 39.1 ng/mL, range = 4.8 ng/mL-40.0 ng/mL). Using TNE-2, which is less impacted by racial differences in nicotine metabolism, produced a comparable pattern of results although reduced the range magnitude.

CONCLUSIONS

Because of similar frequency of cigarette use among polytobacco users, overall cut-points for exclusive cigarette use were not substantially different from cut-points that included polytobacco cigarette use or any tobacco use. Results revealed important differences in sex and race/ethnicity appropriate cut-points when evaluating tobacco use status and established novel urinary TNE-2 cut-points.

IMPACT

These cut-points may be used for biochemical verification of self-reported tobacco use in epidemiologic studies and clinical trials.

Characterization of acrylonitrile exposure in the United States based on urinary n-acetyl-S-(2-cyanoethyl)-L-cysteine (2CYEMA): NHANES 2011-2016

BACKGROUND

Acrylonitrile is a possible human carcinogen that is used in polymers and formed in tobacco smoke. We assessed acrylonitrile exposure in the US population by measuring its urinary metabolites N-acetyl-S-(4-hydroxy-2-methyl-2-buten-1-yl)-L-cysteine (2CYEMA) and N-acetyl-S-(1-cyano-2-hydroxyethyl)-L-cysteine (1CYHEMA) in participants from the 2011-2016 National Health and Nutrition Examination Survey.

OBJECTIVE

To assessed acrylonitrile exposure using population-based biomonitoring data of the US civilian, non-institutionalized population.

METHODS

Laboratory data for 8057 participants were reported for 2CYEMA and 1CYHEMA using ultrahigh-performance liquid chromatography/tandem mass spectrometry. Exclusive tobacco smokers were distinguished from non-users using a combination of self-reporting and serum cotinine data. We used multiple linear regression models to fit 2CYEMA concentrations with sex, age, race/Hispanic origin, and tobacco user group as predictor variables.

RESULTS

The median 2CYEMA level was higher for exclusive cigarette smokers (145 µg/g creatinine) than for non-users (1.38 µg/g creatinine). Compared to unexposed individuals (serum cotinine ≤0.015 ng/ml) and controlling for confounders, presumptive second-hand tobacco smoke exposure (serum cotinine >0.015 to ≤10 ng/ml and 0 cigarettes per day, CPD) was significantly associated with 36% higher 2CYEMA levels (p < 0.0001). Smoking 1-10 CPD was significantly associated with 6720% higher 2CYEMA levels (p < 0.0001).

SIGNIFICANCE

We show that tobacco smoke is an important source of acrylonitrile exposure in the US population and provide important biomonitoring data on acrylonitrile exposure.

Tobacco-Specific Nitrosamines (NNAL, NNN, NAT, and NAB) Exposures in the US Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013-2014)

INTRODUCTION

The tobacco-specific nitrosamines (TSNAs) are an important group of carcinogens found in tobacco and tobacco smoke. To describe and characterize the levels of TSNAs in the Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013-2014), we present four biomarkers of TSNA exposure: N'-nitrosonornicotine, N'-nitrosoanabasine, N'-nitrosoanatabine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) which is the primary urinary metabolite of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone.

METHODS

We measured total TSNAs in 11 522 adults who provided urine using automated solid-phase extraction coupled to isotope dilution liquid chromatography-tandem mass spectrometry. After exclusions in this current analysis, we selected 11 004 NNAL results, 10 753 N'-nitrosonornicotine results, 10 919 N'-nitrosoanatabine results, and 10 996 N'-nitrosoanabasine results for data analysis. Geometric means and correlations were calculated using SAS and SUDAAN.

RESULTS

TSNA concentrations were associated with choice of tobacco product and frequency of use. Among established, every day, exclusive tobacco product users, the geometric mean urinary NNAL concentration was highest for smokeless tobacco users (993.3; 95% confidence interval [CI: 839.2, 1147.3] ng/g creatinine), followed by all types of combustible tobacco product users (285.4; 95% CI: [267.9, 303.0] ng/g creatinine), poly tobacco users (278.6; 95% CI: [254.9, 302.2] ng/g creatinine), and e-cigarette product users (6.3; 95% CI: [4.7, 7.9] ng/g creatinine). TSNA concentrations were higher in every day users than in intermittent users for all the tobacco product groups. Among single product users, exposure to TSNAs differed by sex, age, race/ethnicity, and education. Urinary TSNAs and nicotine metabolite biomarkers were also highly correlated.

CONCLUSIONS

We have provided PATH Study estimates of TSNA exposure among US adult users of a variety of tobacco products. These data can inform future tobacco product and human exposure evaluations and related regulatory activities.

Re-visiting serum cotinine concentrations among various types of smokers including cigarette only smokers: some new, previously unreported results

Data (N = 11614) from National Health and Nutrition Examination Survey (NHANES) for 1999-2016 for US adults aged ≥ 20 years were analyzed by fitting regression models to estimate unadjusted and adjusted geometric means (AGM) for several different groups of smokers. Serum cotinine level ≥ 3.3 ng/mL was used to distinguish smokers from nonsmokers. AGMs for cigarette only, cigar only, dual cigarette/cigar, e-cigarette or dual e-cigarette/cigarette, and smokeless tobacco only smokers were estimated to be 152.5, 65.1, 92.5, 146.3, and 272.0 ng/mL, respectively. Males were found to have higher cotinine levels than females for dual cigarette and cigar smokers, but the reverse was observed for smokeless tobacco users. Non-Hispanic blacks had higher AGMs than non-Hispanic whites for cigarette only smokers, but the reverse was observed for dual cigarette and cigar smokers. For the first time, serum cotinine estimates for those self-reported nonsmokers who were classified to be smokers (29.4 ng/mL) and those smokers for whom self-reported data for use of tobacco products were missing were also estimated (113.8 ng/mL).

Nicotine and Toxicant Exposure Among Concurrent Users (Co-Users) of Tobacco and Cannabis

BACKGROUND

Smoking cannabis may potentially increase exposure to numerous toxic chemicals that are commonly associated with tobacco use. There is a paucity of data related to toxicant exposures among concurrent users of tobacco and cannabis (co-users).

METHODS

Data are from the Population Assessment of Tobacco and Health Study Wave 1 Biomarker Restricted-Use Files. Analyses focused on adults who provided urine samples (N = 5859). Urine samples were analyzed for biomarkers of exposure to nicotine, tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons, and volatile organic compounds. Using weighted linear regression, we compared adjusted geometric mean concentrations of 15 biomarkers between user groups of various tobacco product types according to their self-reported past 30-day cannabis use.

RESULTS

Past 30-day cannabis use was similar across various types of tobacco product use subgroups (range: 13%-23%) and significantly more common compared to non-tobacco users (1.0%; p < .001). Across all groups of tobacco users, those who co-used cannabis exhibited significantly higher concentrations of the biomarker of exposure to acrylonitrile (CYMA) compared to non-cannabis users (by 39%-464%). Tobacco-cannabis co-users also showed significantly elevated levels of the biomarker of exposure to acrylamide (AAMA) compared to exclusive tobacco users, and significantly higher exposure to many polycyclic aromatic hydrocarbons (including fluorene and pyrene).

CONCLUSIONS

Co-users exhibited higher concentrations for biomarkers of exposure to many combustion byproducts, compared to exclusive tobacco users. More robust measurements of cannabis use can address potential confounding in assessments of exposures to tobacco-related constituents, and potential health effects resulting from co-use.

IMPLICATIONS

With disproportionately greater rates of cannabis use occurring among tobacco users, it is critical to consider how concurrent cannabis use may influence health-related outcomes among smokers. Our findings suggest potential additive toxicant exposures among co-users of tobacco and cannabis. Lack of consideration and measurement of cannabis use in assessing tobacco-related exposures may confound estimates thought to be attributable to tobacco, particularly for non-specific biomarkers. Assessing tobacco and cannabis use in tandem will allow for more precise measurement of outcomes related to one or both substances, and can provide additional information on potential health effects related to co-use.

Cluster analysis of urinary tobacco biomarkers among U.S. adults: Population Assessment of Tobacco and Health (PATH) biomarker study (2013-2014)

Tobacco use delivers nicotine, tobacco-specific nitrosamines (TSNAs), volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs), which are metabolized and excreted in urine offering useful biomarkers of exposure. Previous studies compared individual toxicants across tobacco users. Based on a group of biomarkers, cluster analysis was used to define tobacco toxicant exposure profiles. Clusters with distinct exposure profiles, were determined and described, based on levels of urinary biomarkers of exposure to nicotine, TSNAs, VOCs, and PAHs among a national sample of current, established, adult tobacco users, and examine the association of use behavior and cluster membership. The PATH Biomarker Wave 1 data were analyzed. Current established tobacco users with complete urinary biomarker data were included (N = 6724). User groups included cigarette smokers, users of electronic cigarette (ECIG), smokeless tobacco (SLT), and dual and poly tobacco users. Cluster analysis, pairwise comparisons, and multinomial logistic regression were conducted. Cigarette smokers were primarily in clusters with high biomarker concentrations across all groups, but actual concentrations were associated with smoking quantity. A cluster with high TSNAs but low levels of PAHs and VOCs was heavily populated by SLT users. Exclusive ECIG users, depending on use frequency, were predominantly in clusters with low biomarker concentrations, except for one cluster that had relatively high TSNAs. Clusters heavily populated by dual and poly tobacco users were the same as those heavily populated by cigarette smokers. Ten exposure profiles (clusters) were determined and linked to tobacco use behavior. Findings could inform future research and policy initiatives.

Cigarette Smokers Versus Cousers of Cannabis and Cigarettes: Exposure to Toxicants

INTRODUCTION

Cannabis and tobacco couse is common and could expose users to higher levels of toxicants. No studies have examined biomarkers of toxicant exposure in cousers of cannabis and cigarettes, compared with cigarette smokers (CS).

AIMS AND METHODS

Adult daily CS were recruited from 10 US sites for a study of reduced nicotine cigarettes. In this analysis of baseline data, participants were categorized as either cousers of cannabis and tobacco (cousers; N = 167; urine positive for 11-nor-9-carboxy-Δ 9-tetrahydrocannnabinol and self-reported cannabis use ≥1×/week), or CS (N = 911; negative urine and no self-reported cannabis use). Participants who did not meet either definition (N = 172) were excluded. Self-reported tobacco and cannabis use and tobacco and/or combustion-related biomarkers of exposure were compared between groups.

RESULTS

Compared to CS, cousers were younger (couser Mage = 38.96, SD = 13.01; CS Mage = 47.22, SD = 12.72; p < .001) and more likely to be male (cousers = 67.7%, CS = 51.9%, p < .001). There were no group differences in self-reported cigarettes/day, total nicotine equivalents, or breath carbon monoxide, but cousers had greater use of non-cigarette tobacco products. Compared to CS, cousers had higher concentrations of 3-hydroxypropylmercapturic acid, 2-cyanoethylmercapturic acid, S-phenylmercapturic acid, 3-hydroxy-1-methylpropylmercapturic acid (ps < .05), and phenanthrene tetraol (p < .001). No biomarkers were affected by number of cannabis use days/week or days since last cannabis use during baseline (ps > .05).

CONCLUSIONS

Cousers had higher concentrations of biomarkers of exposure than CS, but similar number of cigarettes per day and nicotine exposure. Additional studies are needed to determine whether cannabis and/or alternative tobacco products are driving the increased toxicant exposure.

IMPLICATIONS

Cousers of cannabis and tobacco appear to be exposed to greater levels of harmful chemicals (ie, volatile organic compounds and polycyclic aromatic hydrocarbons), but similar levels of nicotine as CS. It is unclear if the higher levels of toxicant exposure in cousers are due to cannabis use or the increased use of alternative tobacco products compared with CS. It is important for studies examining biomarkers of exposure among CS to account for cannabis use as it may have a significant impact on outcomes. Additionally, further research is needed examining exposure to harmful chemicals among cannabis users.

Analysis of Biomarkers of DNA Damage and Mutagenicity in Mice Exposed to Acrylonitrile

Acrylonitrile (ACN), which is a widely used industrial chemical, induces cancers in the mouse via unresolved mechanisms. For this report, complementary and previously described methods were used to assess in vivo genotoxicity and/or mutagenicity of ACN in several mouse models, including (i) female mice devoid of cytochrome P450 2E1 (CYP2E1), which yields the epoxide intermediate cyanoethylene oxide (CEO), (ii) male lacZ transgenic mice, and (iii) female (wild-type) B6C3F1 mice. Exposures of wild-type mice and CYP2E1-null mice to ACN at 0, 2.5 (wild-type mice only), 10, 20, or 60 (CYP2E1-null mice only) mg/kg body weight by gavage for 6 weeks (5 days/week) produced no elevations in the frequencies of micronucleated erythrocytes, but induced significant dose-dependent increases in DNA damage, detected by the alkaline (pH >13) Comet assay, in one target tissue (forestomach) and one nontarget tissue (liver) of wild-type mice only. ACN exposures by gavage also caused significant dose-related elevations in the frequencies of mutations in the hypoxanthine-guanine phosphoribosyltransferase (Hprt) reporter gene of T-lymphocytes from spleens of wild-type mice; however, Hprt mutant frequencies were significantly increased in CYP2E1-null mice only at a high dose of ACN (60 mg/kg) that is lethal to wild-type mice. Similarly, drinking water exposures of lacZ transgenic mice to 0, 100, 500, or 750 ppm ACN for 4 weeks caused significant dose-dependent elevations in Hprt mutant frequencies in splenic T-cells; however, these ACN exposures did not increase the frequency of lacZ transgene mutations above spontaneous background levels in several tissues from the same animals. Together, the Comet assay and Hprt mutant frequency data from these studies indicate that oxidative metabolism of ACN by CYP2E1 to CEO is central to the induction of the majority of DNA damage and mutations in ACN-exposed mice, but ACN itself also may contribute to the carcinogenic modes of action via mechanisms involving direct and/or indirect DNA reactivity.

Diminished Returns of Educational Attainment on Heart Disease among Black Americans

Background

Socioeconomic Status (SES) indicators, such as educational attainment, are social determinants of heart disease. Marginalization related Diminished Returns (MDRs) refer to smaller health benefits of high SES for racial and ethnic minorities compared to the majority group. It is still unknown, however, if MDRs also apply to the effects of education on heart disease.

Purpose

Using a nationally representative sample, we explored racial/ethnic variation in the link between educational attainment and heart disease among American adults.

Methods

We analyzed data (n=25,659) from a nationally representative survey of American adults in 2013. The first wave of the Population Assessment of Tobacco and Health - Adult (PATH-Adult) study was used. The independent variable was education (college graduate, high school graduate, less than a high school diploma). The dependent variable was any heart disease. Age and gender were the covariates. Race, as well as ethnicity, were the moderators. Logistic regressions were used to analyze the data.

Results

Individuals with higher educational attainment had lower odds of heart disease. Race and ethnicity showed statistically significant interactions with education, suggesting that the protective effect of higher education on reducing odds of heart disease was smaller for Hispanic and Black people than for non-Hispanic and White individuals.

Conclusion

Education reduces the risk of heart disease better among non-Hispanic Whites than for Hispanics and Blacks. Therefore, we may expect a disproportionately higher than expected risk of heart disease in Hispanics and Blacks with high educational attainment. Future research should test if the presence of high levels of environmental and behavioral risk factors contribute to the high risk of heart disease in highly educated Black and Hispanic Americans. Policymakers should not reduce health inequalities to just gaps in SES because disparities are present across SES levels, with high SES Blacks and Hispanics remaining at risk of health problems.

Race, Ethnicity, Socioeconomic Status, and Chronic Lung Disease in the U.S

BACKGROUND

Higher socioeconomic status (SES) indicators such as educational attainment and income reduce the risk of chronic lung diseases (CLDs) such as Chronic Obstructive Pulmonary Disease (COPD), emphysema, chronic bronchitis, and asthma. Marginalization-related Diminished Returns (MDRs) refer to smaller health benefits of high SES for marginalized populations such as racial and ethnic minorities compared to the socially privileged groups such as non-Hispanic Whites. It is still unknown, however, if MDRs also apply to the effects of education and income on CLDs.

PURPOSE

Using a nationally representative sample, the current study explored racial and ethnic variation in the associations between educational attainment and income and CLDs among American adults.

METHODS

In this study, we analyzed data (n = 25,659) from a nationally representative survey of American adults in 2013 and 2014. Wave one of the Population Assessment of Tobacco and Health (PATH)-Adult study was used. The independent variables were educational attainment (less than high school = 1, high school graduate = 2, and college graduate =3) and income (living out of poverty =1, living in poverty = 0). The dependent variable was any CLDs (i.e., COPD, emphysema, chronic bronchitis, and asthma). Age, gender, employment, and region were the covariates. Race and ethnicity were the moderators. Logistic regressions were fitted to analyze the data.

RESULTS

Individuals with higher educational attainment and those with higher income (who lived out of poverty) had lower odds of CLDs. Race and ethnicity showed statistically significant interactions with educational attainment and income, suggesting that the protective effects of high education and income on reducing odds of CLDs were smaller for Blacks and Hispanics than for non-Hispanic Whites.

CONCLUSIONS

Education and income better reduce the risk of CLDs among Whites than Hispanics and Blacks. That means we should expect disproportionately higher than expected risk of CLDs in Hispanics and Blacks with high SES. Future research should test if high levels of environmental risk factors contribute to the high risk of CLDs in high income and highly educated Black and Hispanic Americans. Policy makers should not reduce health inequalities to SES gaps because disparities sustain across SES levels, with high SES Blacks and Hispanics remaining at risk of health problems.

Use of biomarker testing in lung cancer among Puerto Rico and Florida Physicians: Results of a comparative study

BACKGROUND

Lung cancer biomarker-driven therapies are the gold standard of treatment and recent studies suggest a higher prevalence of specific targetable biomarkers among Hispanic/Latinos (H/L) than Non-Hispanic Whites (NHW). The study aimed (1) to identify Florida (FL) and Puerto Rico (PR) physicians' knowledge and perceived value of newer genomic data regarding race/ethnicity in relation to optimal lung cancer treatment and survival; and (2) to identify modifiable practice barriers both across and within each location regarding biomarker testing in lung cancer.

METHODS

A 25-item survey was administered to a stratified random sample of physicians in FL and PR (medical oncologists, radiation oncologists, pulmonologists, and pathologists). Questions targeted domains of biomarker knowledge, attitudes toward testing, barriers, and practice behaviors regarding lung cancer biomarker testing.

RESULTS

The response rate was 45%. Participants identified guiding treatment decisions (82%) and personalizing treatments for patients (78%) as key benefits to mutation testing. PR physicians were more likely (p=0.022) to believe H/L had an elevated incidence of targetable epidermal growth factor receptor (EGFR) mutations compared to NHW. They also perceived lack of appropriate testing resources as a primary barrier compared to FL physicians (43.6% vs. 20.6%, p<0.001), whereas FL physicians identified mutation tests not conducted routinely as part of patient diagnosis as a primary barrier (43.1% vs 24.2%, p= 0.008).

CONCLUSIONS

Practice behaviors differed by specialty and between locations, and differences were noted concerning physician's preferences for ordering mutation testing, indicating a clear need for education among physicians in both locations.

IMPACT

Educating physicians regarding biomarker testing is imperative to improve patient care.