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BACKGROUND: Acrolein is a highly reactive α,β unsaturated aldehyde and respiratory irritant. Acrolein is formed during combustion (e.g., burning tobacco or biomass), during high-temperature cooking of foods, and in vivo as a product of oxidative stress and polyamine metabolism. No biomonitoring reference data have been reported to characterize acrolein exposure for the U.S. population. OBJECTIVES: Our goals were to a) evaluate two acrolein metabolites in urine--N-acetyl-S-(3-hydroxypropyl)-L-cysteine (3HPMA) and N-acetyl-S-(2-carboxyethyl)-L-cysteine (CEMA)--as biomarkers of exposure to acrolein for the U.S. population by age, sex, race, and smoking status; and b) assess tobacco smoke as a predictor of acrolein exposure. METHODS: We analyzed urine from National Health and Nutrition Examination Survey (NHANES 2005-2006) participants [greater than or equal to]12 years old (n = 2,866) for 3HPMA and CEMA using ultra-high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UPLC/ESI-MSMS). Sample-weighted linear regression models stratified for nontobacco users versus tobacco smokers (as defined by serum cotinine and self-report) characterized the association of urinary 3HPMA and CEMA with tobacco smoke exposure, adjusting for urinary creatinine, sex, age, and race/ethnicity. RESULTS: 3HPMA and CEMA levels were higher among tobacco smokers (cigarettes, cigars, and pipe users) than among non-tobacco users. The median 3HPMA levels for tobacco smokers and non-tobacco users were 1,089 and 219 µg/g creatinine, respectively. Similarly, median CEMA levels were 203 µg/g creatinine for tobacco smokers and 78.8 µg/g creatinine for non-tobacco users. Regression analysis showed that serum cotinine was a significant positive predictor (p < 0.0001) of both 3HPMA and CEMA among tobacco smokers. CONCLUSIONS: Tobacco smoke was a significant predictor of acrolein exposure in the U.S. population. Environ Health Perspect 123:1302-1308; http://dx.doi.org/10.1289/ehp.1409251, Introduction Acrolein is a chemical contaminant that is ubiquitous in the environment. It is formed from carbohydrates, vegetable oils, animal fats, and amino acids during heating of foods and by [...]

Background: Heterocyclic aromatic amines (HAA) are a group of hazardous substances produced during combustion of tobacco or high-temperature cooking of meats. 2-Amino-9H-pyrido[2,3-b]indole (AαC) is a major carcinogenic HAA in tobacco smoke. Methods: Urinary AαC, used as a marker of AαC exposure, was analyzed on spot urine samples from adult participants of the 2013-2014 cycle of the National Health and Nutrition Examination Survey (N = 1,792). AαC was measured using isotope-dilution liquid chromatography-tandem mass spectrometry. Exclusive combusted tobacco smokers were differentiated from nonusers of tobacco products through both self-report and serum cotinine data. Results: Among exclusive smokers, sample-weighted median urinary AαC was 40 times higher than nonusers. Sample-weighted regression models showed that urinary AαC increased significantly with serum cotinine among both exclusive tobacco users and nonusers with secondhand smoke exposure. Among nonusers, eating beef cooked at high temperature was associated with a significant increase in urinary AαC, whereas consuming vegetables was associated with decreased AαC. In addition, smoking one-half pack of cigarettes per day was associated with a significant increase of 23.6 pg AαC/mL calculated at geometric mean of AαC, controlling for potential confounders. In comparison, increase in AαC attributable to consuming the 99th percentile of beef cooked at high temperature was 0.99 pg AαC/mL. Conclusions: Both exclusive smokers and nonusers of tobacco in the general U.S. population are exposed to AαC from tobacco smoke, with additional, lesser contributions from certain dietary components. [ABSTRACT FROM AUTHOR]

Objective: Our objective was to improve understanding of the differences in cigarette use behavior and exposure for participants smoking their own brand of cigarettes in a clinical setting versus smoking under natural conditions. Methods: Adult daily smokers (N = 163) attended 2 clinic visits where they smoked through a CReSS™ topography device. Participants collected cigarette butts smoked without a CReSS™ device and completed a diary of location, mood, and activity for each cigarette smoked. Cigarette butts were used to determine mouth level nicotine (MLN). Least square means (LSMs) were estimated from mixed effects models. Results: The LSM for MLN was higher among participants who smoked cigarettes in the clinical setting. LSM MLN was 1.589 [95% CI: 1.312, 1.924] mg/cig for cigarettes smoked in the clinic and 1.087 [95% CI: 0.902, 1.310] mg/cig for cigarettes smoked outside of the clinic; we found differences between race and sex. Conclusions: Our results show nicotine intake and some smoking behavior are significantly biased upwards when studied in a clinical setting. Therefore, tobacco smoke exposure determinations in a clinical setting may not be completely generalizable to smoke exposure determinations in naturalistic settings. [ABSTRACT FROM AUTHOR]

BACKGROUND: Electronic directly observed therapy (eDOT) has been proposed as an alternative to traditional in-person DOT (ipDOT) for monitoring TB treatment adherence. Information about the comparative performance and implementation of eDOT is limited. METHODS: The frequency of challenges during DOT, challenge type, and effect on medication observation were documented by DOT method during a crossover, noninferiority randomized controlled trial. A logistic mixed-effects model that adjusted for the study design was used to estimate the percentage of successfully observed doses when challenges occurred. RESULTS: A total of 20,097 medication doses were scheduled for observation with either eDOT (15,405/20,097; 76.7%) or ipDOT (4,692/20,097; 23.3%) for 213 study participants. In total, one or more challenges occurred during 17.3% (2,672/15,405) of eDOT sessions and 15.6% (730/4,692) of ipDOT sessions. Among 4,374 documented challenges, 27.3% ( n = 1,192) were characterized as technical, 65.9% ( n = 2,881) were patient-related, and 6.9% ( n = 301) were program-related. Estimated from the logistic model ( n = 6,782 doses, 173 participants), the adjusted percentage of doses successfully observed during problematic sessions was 21.7% (95% CI 11.2-37.8) for eDOT and 4.2% (95% CI 1.1-14.7) for ipDOT. CONCLUSION: Compared to ipDOT, challenges were encountered in a slightly higher percentage of eDOT sessions but were more often resolved to enable successful dose observation during problematic sessions.

Objective: We examined differences between nicotine concentrations and pH in cigarette and cigar tobacco filler., Methods: Nicotine and pH levels for 50 cigarette and 75 cigar brands were measured. Non-mentholated and mentholated cigarette products were included in the analysis along with several cigar types as identified by the manufacturer: large cigars, pipe tobacco cigars, cigarillos, mini cigarillos, and little cigars., Results: There were significant differences found between pH and nicotine for cigarette and cigar tobacco products. Mean nicotine concentrations in cigarettes (19.2 mg/g) and large cigars (15.4 mg/g) were higher than the other cigars types, especially the pipe tobacco cigars (8.79 mg/g). The mean pH for cigarettes was pH 5.46. Large cigars had the highest mean pH value (pH 6.10) and pipe tobacco cigars had the lowest (pH 5.05)., Conclusions: Although cigarettes are the most common combustible tobacco product used worldwide, cigar use remains popular. Our research provides a means to investigate the possibility of distinguishing the 2 tobacco product types and offers information on nicotine and pH across a wide range of cigarette and cigar varieties that may be beneficial to help establish tobacco policies and regulations across product types., Competing Interests: Conflict of Interest Statement The authors confirm no conflicts of interest.