Carbon monoxide poisoning from waterpipe smoking: a retrospective cohort study

Biomarkers of Waterpipe Tobacco Smoke Exposure: A Systematic Review and Meta-Analysis

INTRODUCTION

The prevalence of waterpipe tobacco smoking is increasing globally. Biomarkers of waterpipe tobacco smoke (WTS) exposure are less studied.

AIMS AND METHODS

To identify the types of biomarkers of WTS exposure and estimate changes in biomarker concentrations pre- to post-WTS exposure. PubMed, Embase, Web of Science, CINAHL Plus, PsycINFO, and Cochrane Library were searched for studies up to April 24, 2023. The types of biomarkers were identified. Random-effects models were used to estimate changes in biomarker concentrations pre- to post-WTS exposure.

RESULTS

Seventy-three studies involving 3755 participants exposed to WTS (49% male, mean age: 24.8 years) and 11 types of biomarkers of WTS exposure were identified. The biomarkers included tobacco alkaloids, expired carbon monoxide (eCO), carboxyhemoglobin (COHb), tobacco-specific nitrosamines, volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), heavy metals, unmetabolized VOCs, unmetabolized PAHs, furan metabolites, and heterocyclic aromatic amines. Compared with pre-WTS exposure, eCO (breath; mean difference [MD] 27.00 ppm; 95% confidence interval [CI]: 20.91 to 33.08), COHb (blood; MD 4.30%; 95%CI: 2.57 to 6.03), COHb (breath; MD 7.14%; 95%CI: 4.96 to 9.31), nicotine (blood; MD 8.23 ng/mL; 95%CI: 6.27 to 10.19), and cotinine (urine; MD 110.40 ng/mL; 95%CI: 46.26 to 174.54) significantly increased post-WTS exposure.

CONCLUSIONS

Biomarkers of WTS exposure were systematically identified. The similarity between the biomarkers of WTS exposure and those of cigarette smoke and higher concentrations of some biomarkers post-WTS exposure underscore the need for further research on applying biomarkers in surveillance, interventions, and regulations to mitigate the harms of waterpipe tobacco smoking.

IMPLICATIONS

This study provides the first comprehensive overview of biomarkers investigated and available for assessing WTS exposure and their concentration changes in the human body. Researchers can use biomarkers such as eCO, COHb, nicotine, and cotinine to measure the health risks associated with WTS exposure and objectively evaluate the effectiveness of public health interventions aimed at reducing waterpipe tobacco smoking. Public health policymaking can also be informed through increased biomarker concentrations following WTS exposure, to implement regulations and public health education campaigns on limiting or preventing waterpipe tobacco smoking.

Waterpipe vs non-Waterpipe carbon monoxide poisoning: Comparison of patient characteristics, clinical presentation and outcomes

OBJECTIVE

The aim of this study is to describe the difference between carboxyhemoglobin (CO-Hb) acute poisoning caused by waterpipe vs non-waterpipe exposures as they relate to demographics, clinical presentations and outcome of patients.

DESIGN

Retrospective cohort study conducted in the Emergency Department (ED) at the Lebanon.

PATIENTS

All adult patients presenting with a CO-Hb level ≥ 10 between January 2019 and August 2023 with exposure types stratified as waterpipe or non-waterpipe.

MEASUREMENTS AND MAIN RESULTS

111 ED visits were identified. Among these, 73.9% were attributed to waterpipe exposure, while 26.1% were non-waterpipe sources. These included cigarette smoking (17.2%), burning coal (24.1%), fire incidents (3.6%), gas leaks (6.9%), heating device use (10.3%), and undocumented sources (37.9%). Patients with waterpipe-related carbon monoxide exposure were younger (41 vs 50 years, p = 0.015) women (63.4 vs 41.4%, p = 0.039) with less comorbidities compared to non-waterpipe exposures (22.2 vs 41.4%, p = 0.047). Waterpipe smokers were more likely to present during the summer (42.7 vs 13.8%, p = 0.002) and have shorter ED length of stays (3.9 vs 4.5 h, p = 0.03). A higher percentage of waterpipe smokers presented with syncope (52.4 vs 17.2%, p = 0.001) whereas cough/dyspnea were more common in non-waterpipe exposures (31 vs 9.8%, p = 0.006). The initial CO-Hb level was found to be significantly higher in waterpipe exposure as compared to non-waterpipe (19.7 vs 13.7, p = 0.004). Non-waterpipe exposures were more likely to be admitted to the hospital (24.1 vs 4.9%, p = 0.015). Waterpipe smokers had significantly higher odds of experiencing syncope, with a 5.74-fold increase in risk compared to those exposed to non-waterpipe sources (p = 0.004) irrespective of their CO-Hb level. Furthermore, males had significantly lower odds of syncope as compared to females, following carbon monoxide exposure (aOR 0.31, 95% CI 0.13-0.74).

CONCLUSION

CO-Hb poisoning related to waterpipe smoking has distinctive features. Syncope is a commonly associated presentation that should solicit a focused social history in communities where waterpipe smoking is common. Furthermore, CO-Hb poisoning should remain on the differential in patients presenting with headache, syncope, dizziness, vomiting or shortness of breath, even outside of the non-waterpipe exposure peaks of winter season.

Carbon monoxide intoxication with a CO-Hb of 30% while smoking waterpipe: a case report

Carbon monoxide (CO) poisoning is a significant public health issue and a considerable economic burden in developed countries. While the majority of non-fire-related CO poisonings are attributed to gas heating, there are several other less recognized sources that should be considered in the initial differential diagnosis.The patient in this case was a 21-year-old who experienced a brief episode of loss of consciousness and was subsequently admitted to the Emergency department. Upon evaluation, the patient was diagnosed with CO poisoning, which necessitated hyperbaric oxygen therapy to mitigate the effects of this toxic exposure.Despite exhibiting harmful symptoms initially, the patient stated in a phone interview two and a half years post-incident that they have not experienced any enduring effects such as cardiac arrhythmia or concentration deficits. While their understanding of the risks associated with waterpipe smoking has increased, it has not influenced any major changes in their waterpipe smoking habits.

Indoor Exposure and Regional Inhaled Deposited Dose Rate during Smoking and Incense Stick Burning-The Jordanian Case as an Example for Eastern Mediterranean Conditions

Tobacco smoking and incense burning are commonly used in Jordanian microenvironments. While smoking in Jordan is prohibited inside closed spaces, incense burning remains uncontrolled. In this study, particle size distributions (diameter 0.01-25 µm) were measured and inhaled deposited dose rates were calculated during typical smoking and incense stick-burning scenarios inside a closed room, and the exposure was summarized in terms of number and mass concentrations of submicron (PN_Sub) and fine particles (PM_2.5). During cigarette smoking and incense stick-burning scenarios, the particle number concentrations exceeded 3 × 10⁵ cm^-3. They exceeded 5 × 10⁵ cm^-3 during shisha smoking. The emission rates were 1.9 × 10¹⁰, 6.8 × 10¹⁰, and 1.7 × 10¹⁰ particles/s, respectively, for incense, cigarettes, and shisha. That corresponded to about 7, 80, and 120 µg/s, respectively. Males received higher dose rates than females, with about 75% and 55% in the pulmonary/alveolar during walking and standing, respectively. The total dose rates were in the order of 10¹²-10¹³ #/h (10³-10⁴ µg/h), respectively, for PN_Sub and PM_2.5. The above reported concentrations, emissions rates, and dose rates are considered seriously high, recalling the fact that aerosols emitted during such scenarios consist of a vast range of toxicant compounds.

Carbon Monoxide Signaling: Examining Its Engagement with Various Molecular Targets in the Context of Binding Affinity, Concentration, and Biologic Response

Carbon monoxide (CO) has been firmly established as an endogenous signaling molecule with a variety of pathophysiological and pharmacological functions, including immunomodulation, organ protection, and circadian clock regulation, among many others. In terms of its molecular mechanism(s) of action, CO is known to bind to a large number of hemoproteins with at least 25 identified targets, including hemoglobin, myoglobin, neuroglobin, cytochrome c oxidase, cytochrome P450, soluble guanylyl cyclase, myeloperoxidase, and some ion channels with dissociation constant values spanning the range of sub-nM to high μM. Although CO's binding affinity with a large number of targets has been extensively studied and firmly established, there is a pressing need to incorporate such binding information into the analysis of CO's biologic response in the context of affinity and dosage. Especially important is to understand the reservoir role of hemoglobin in CO storage, transport, distribution, and transfer. We critically review the literature and inject a sense of quantitative assessment into our analyses of the various relationships among binding affinity, CO concentration, target occupancy level, and anticipated pharmacological actions. We hope that this review presents a picture of the overall landscape of CO's engagement with various targets, stimulates additional research, and helps to move the CO field in the direction of examining individual targets in the context of all of the targets and the concentration of available CO. We believe that such work will help the further understanding of the relationship of CO concentration and its pathophysiological functions and the eventual development of CO-based therapeutics. SIGNIFICANCE STATEMENT: The further development of carbon monoxide (CO) as a therapeutic agent will significantly rely on the understanding of CO's engagement with therapeutically relevant targets of varying affinity. This review critically examines the literature by quantitatively analyzing the intricate relationships among targets, target affinity for CO, CO level, and the affinity state of carboxyhemoglobin and provide a holistic approach to examining the molecular mechanism(s) of action for CO.

S2k guideline diagnosis and treatment of carbon monoxide poisoning

Carbon monoxide (CO) can occur in numerous situations and ambient conditions, such as fire smoke, indoor fireplaces, silos containing large quantities of wood pellets, engine exhaust fumes, and when using hookahs. Symptoms of CO poisoning are nonspecific and can range from dizziness, headache, and angina pectoris to unconsciousness and death. This guideline presents the current state of knowledge and national recommendations on the diagnosis and treatment of patients with CO poisoning. The diagnosis of CO poisoning is based on clinical symptoms and proven or probable exposure to CO. Negative carboxyhemoglobin (COHb) levels should not rule out CO poisoning if the history and symptoms are consistent with this phenomenon. Reduced oxygen-carrying capacity, impairment of the cellular respiratory chain, and immunomodulatory processes may result in myocardial and central nervous tissue damage even after a reduction in COHb. If CO poisoning is suspected, 100% oxygen breathing should be immediately initiated in the prehospital setting. Clinical symptoms do not correlate with COHb elimination from the blood; therefore, COHb monitoring alone is unsuitable for treatment management. Especially in the absence of improvement despite treatment, a reevaluation for other possible differential diagnoses ought to be performed. Evidence regarding the benefit of hyperbaric oxygen therapy (HBOT) is scant and the subject of controversy due to the heterogeneity of studies. If required, HBOT should be initiated within 6 h. All patients with CO poisoning should be informed about the risk of delayed neurological sequelae (DNS).

Markers of oxidative stress and toxicant exposure among young waterpipe smokers in the USA

Waterpipe (aka hookah) tobacco smokers are exposed to toxicants that can lead to oxidative DNA and RNA damage, a precursor to chronic disease formation. This study assessed toxicant exposure and biomarkers of DNA [8-oxo-7, 8-dihydro-2'-deoxyguanosine (8-oxodG)] and RNA [8-oxo-7,8-dihydroguanosine (8-oxoGuo)] oxidative damage during smoking of flavored and non-flavored waterpipe tobacco. Thirty waterpipe smokers completed two counterbalanced 2-h lab waterpipe smoking sessions (flavored vs. non-flavored waterpipe tobacco). Urinary concentrations of 8-oxodG and 8-oxoGuo and expired carbon monoxide (eCO) were measured before and after the smoking sessions. A significant increase in the urinary concentrations of 8-oxodG (from 2.12 ± 0.83 to 2.35 ± 0.91 ng/mg creatinine, p = 0.024) and 8-oxoGuo (from 2.96 ± 0.84 to 3.45 ± 0.76 ng/mg creatinine, p = 0.003) were observed after smoking the non-flavored and flavored waterpipe tobacco, respectively. Our results also showed that the mean ± SD of eCO increased significantly after smoking the flavored (from 1.3 ± 1.1 to 20.3 ± 23.6 ppm, p < 0.001) and non-flavored waterpipe tobacco (from 1.8 ± 1.2 to 24.5 ± 26.1 ppm, p < 0.001). There were no significant differences in the means of 8-oxodG (p = 0.576), 8-oxoGuo (p = 0.108), and eCO (p = 0.170) between the flavored and non-flavored tobacco sessions. Smoking non-flavored and flavored waterpipe tobacco leads to oxidative stress and toxicant exposure. Our findings add to the existing evidence about the adverse effects of waterpipe tobacco smoking (WTS) and the need for strong policies to inform and protect young people from the risks of WTS.

Water Pipe (Hookah) Smoking and Cardiovascular Disease Risk: A Scientific Statement From the American Heart Association

Tobacco smoking with a water pipe or hookah is increasing globally. There are millions of water pipe tobacco smokers worldwide, and in the United States, water pipe use is more common among youth and young adults than among adults. The spread of water pipe tobacco smoking has been abetted by the marketing of flavored tobacco, a social media environment that promotes water pipe smoking, and misperceptions about the addictive potential and potential adverse health effects of this form of tobacco use. There is growing evidence that water pipe tobacco smoking affects heart rate, blood pressure regulation, baroreflex sensitivity, tissue oxygenation, and vascular function over the short term. Long-term water pipe use is associated with increased risk of coronary artery disease. Several harmful or potentially harmful substances present in cigarette smoke are also present in water pipe smoke, often at levels exceeding those found in cigarette smoke. Water pipe tobacco smokers have a higher risk of initiation of cigarette smoking than never smokers. Future studies that focus on the long-term adverse health effects of intermittent water pipe tobacco use are critical to strengthen the evidence base and to inform the regulation of water pipe products and use. The objectives of this statement are to describe the design and operation of water pipes and their use patterns, to identify harmful and potentially harmful constituents in water pipe smoke, to document the cardiovascular risks of water pipe use, to review current approaches to water pipe smoking cessation, and to offer guidance to healthcare providers for the identification and treatment of individuals who smoke tobacco using water pipes.

Prognostic factors of carbon monoxide poisoning in Taiwan: a retrospective observational study

OBJECTIVES

To identify the risk factors related to the prognosis of carbon monoxide (CO)-poisoned patients in the hospital.

DESIGN

Retrospective observational study.

SETTING

Tri-Service General Hospital, Taiwan.

METHODS

We conducted a review of the medical records of 669 CO-poisoned patients, who were admitted to the Department of Emergency, Tri-Service General Hospital, Taiwan, from 2009 to 2014. Demographic, clinical and laboratory data were collected for analysis. In the study, the end points for poor outcome were patients who either still had sequelae, were bedridden or died after treatment. The independent t-test, χ² test and binary logistic regression were used to identify the association between the prognostic factors and the outcomes.

RESULTS

The logistic regression analysis confirmed that the Glasgow Coma Scale (GCS) score (p=0.008) and blood urea nitrogen (BUN) (p=0.002) were related to poor outcomes. Furthermore, the receiver operating characteristic (ROC) curve showed that the cut-off point of intubation days was 1.5 days (area under the ROC curve [AUC]=0.793) for all patients and 2.5 days (AUC=0.817) for patients with intubation when predicting poor outcomes.

CONCLUSION

We identified the factors that most strongly predict the prognosis of CO poisoning, including the GCS score, serum BUN and intubation days. Moreover, the number of hyperbaric oxygen treatments seems to have impact of the outcome.

Waterpipe smoking: the pressing need for risk communication

Introduction: Waterpipe (WP) smoking is an important public health problem that is rapidly evolving globally. Much of WP spread among youth is perpetuated by a misperception of reduced harms compared to cigarettes. Increasing awareness about WP smoking harms through health warning labels (HWLs) represents a promising policy and regulatory strategy to curb WP smoking. Areas covered: Peer-reviewed publications indexed in PubMed and CINAHL were searched in March 2019. This review focuses on the current knowledge of WP smoking characteristics, its spread and patterns of use globally, and some of the major WP-related health effects. This knowledge is utilized to advance a promising policy and regulatory avenue to curb WP smoking by increasing awareness of its potential harms through HWLs. It also addresses product configuration and unique features that influence the adaptation of HWLs for WP smoking. Expert opinion: HWLs are effective in communicating smoking-related risks to WP smokers in a way that affects their smoking behavior and experience as well as interest in quitting. Although based on limited data, the WP device appears to be a promising location for HWLs as it offers prolonged contact with smokers and those surrounding them.

Acute and Chronic Carbon Monoxide Toxicity from Tobacco Smoking

Introduction: Carbon monoxide (CO) is produced from incomplete combustion of hydrocarbons and is a by-product of tobacco smoking. Chronic cigarette smokers often have carboxyhemoglobin (COHb) concentrations as high as 10%. We report a case of severely elevated COHb and polycythemia because of tobacco smoking and provide a review of the literature regarding elevated COHb in smokers. Materials and Methods: A comprehensive search of PubMed and Google Scholar was performed looking for articles on tobacco smoking and CO, COHb, CO poisoning, cigarettes, pipes, cigars and water pipes/hookah smokers. Result: COHb levels in frequent cigarette smokers generally range from 4.2% presmoking to 8.6% postsmoking. A heavy cigarette smoker presented twice with symptoms of CO toxicity and was found to have levels 21.8 to 24.2%. Cigar smokers have been found to have COHb ranging as high as 13.0 to 38.6% in case reports. Waterpipe or “hookah” smokers generally have COHb levels 10.1% +/−2.5% and case reports, and series of even higher levels associated with CO toxicity symptoms are common. Waterpipe smokers have been found to have COHb levels as high as 39.2% after smoking. Conclusions: Many active duty military and military veterans are tobacco smokers and these patients and their health care providers should be aware of the adverse effects of CO toxicity from tobacco smoking. Patients may have symptoms such as headaches, syncope, and ataxia in the setting of acute CO toxicity; however, the chronic effects of CO may not be completely understood. Future work could explore chronic CO toxicity and its effects on strength and exercise tolerance in military personnel and provide education to service members, veterans, and health care providers.

The Diagnosis and Treatment of Carbon Monoxide Poisoning

BACKGROUND

The symptoms of carbon monoxide (CO) poisoning are nonspecific, ranging from dizziness and headache to unconsciousness and death. A German national guideline on the diagnosis and treatment of this condition is lacking at present.

METHODS

This review is based on a selective literature search in the PubMed and Cochrane databases, as well as on existing guidelines from abroad and expert recommendations on diagnosis and treatment.

RESULTS

The initiation of 100% oxygen breathing as early as possible is the most important treatment for carbon monoxide poisoning. In case of CO poisoning, the reduced oxygen-carrying capacity of the blood, impairment of the cellular respiratory chain, and immune-modulating processes can lead to tissue injury in the myocardium and brain even after lowering of the carboxyhemoglobin (COHb) concentration. In patients with severe carbon monoxide poisoning, an ECG should be obtained and biomarkers for cardiac ischemia should be measured. Hyperbaric oxygen therapy (HBOT) should be critically considered and initiated within six hours in patients with neurologic deficits, unconsciousness, cardiac ischemia, pregnancy, and/or a very high COHb concentration. At present, there is no general recommendation for HBOT, in view of the heterogeneous state of the evidence from multiple trials. Therapeutic decision-making is directed toward the avoidance of sequelae such as cognitive dysfunction and cardiac complications, and the reduction of mortality. Smoke intoxication must be considered in the differential diagnosis. The state of the evidence on the diagnosis and treatment of this condition is not entirely clear. Alternative or supplementary pharmacological treatments now exist only on an experimental basis.

CONCLUSION

High-quality, prospective, randomized trials that would enable a definitive judgment of the efficacy of HBOT are currently lacking.

Waterpipe or Hookah-Related Poisoning Events Among U.S. Adolescents and Young Adults

PURPOSE

Waterpipe or hookah use is associated with carbon monoxide poisoning and effects such as nausea and vomiting. We examined the public health burden of poisoning events involving hookah tobacco in the U.S., especially among adolescents and young adults.

METHODS

We analyzed events involving hookah tobacco that were reported to U.S. poison control centers between 2001 and 2017 by age and over time as well as by medical outcome, health care level, and clinical effects.

RESULTS

A total of 276 relevant poisoning events involving hookah were reported. Among the 248 individuals with a specific age reported, 35 (14.1%) were aged between 10 and 17 years and 136 (54.8%) were aged between 18 and 24 years. Common clinical effects included dizziness/vertigo, nausea, headache, and vomiting.

CONCLUSIONS

Hookah tobacco use is associated with poisoning events consistent with exposure to high levels of carbon monoxide.

[Treatment of carbon monoxide poisoning in Germany : A retrospective single center analysis]

BACKGROUND

The symptoms of acute carbon monoxide (CO) poisoning are unspecific, ranging from headaches to unconsciousness and death. In addition to acute symptoms, delayed severe neurological sequelae may occur. While a total of 440 deaths by CO poisoning were registered in Germany in 1999, a total of 594 patients died (0.73 per 100,000 inhabitants) in 2014 and in 2015 the number even increased to 648 deaths. A national database on clinical symptoms, course of illness or quality of care concerning CO poisoning does not yet exist.

METHODS

The treatment data of patients admitted to the Hyperbaric Emergency Centre Wiesbaden (HEC) from 2013 to 2017 with CO poisoning formed the basis of the study. This was a comparative evaluation of patient demographics, poisoning sources, symptom spectrum, course of treatment and time intervals registered on the preclinical and clinical levels.

RESULTS

From 2013 to 2017 a total of 476 patients (282 men and 194 women) with an average non-invasively measured CO-Hb of 15% (Q_0.25 = 7.6%, Q_0.75 = 22.3%) were treated with hyperbaric oxygen. Heaters (n = 131), charcoal barbecues (n = 93), fires (n = 90), hookahs (n = 78) and combustion engines (n = 37) were the most frequent CO sources identified. Headaches, vertigo, nausea and syncope were the most prevalent symptoms. A median of 91 min (Q_0.25 = 53 min; Q_0.75 = 147 min) passed between first medical contact and BGA-validated diagnosis. In total, 151 patients were transferred directly to the HEC, whereas 325 patients were secondarily transferred. The delay in this subgroup took 183 min (median Q_0.25 = 138 min; Q_0.75 = 248 min). After receiving the first hyperbaric treatment, 80% were free of symptoms. Remaining symptoms included headache (10%), fatigue (8%), vertigo (5%) and nausea (3%) and 45 patients terminated further treatment. Of the patients 417 received a second hyperbaric treatment and 370 patients were treated 3 times. After the third treatment, 89% were free of symptoms and 5% still reported headaches, 3% vertigo and 2% fatigue. In total, 6 patients died and 430 patients were symptom-free after treatment.

CONCLUSION

Commonly known sources (fire, charcoal grills) aside, many poisonings by smoking a hookah were observed. This study highlights the importance of considering CO poisoning as a differential diagnosis when encountering patients, especially of younger age, with non-specific neurological symptoms, as well as the importance of early initiation of treatment. A direct correlation between CO-Hb values (whether measured noninvasively or by invasive BGA) and the initial symptoms could not be demonstrated. In total, substantial time expired between the diagnosis and start of treatment of patients transported to a primary care hospital compared to those transported directly to the HEC. Although analysis showed adequate treatment with oxygen in the preclinical interval, administration of oxygen during primary hospital stay showed room for improvement. Introducing a national CO poisoning register and uniform treatment guidelines could improve in-house clinical processes. Multicenter studies are needed to close the gaps identified in the quality of care in Germany.

Chemical Characterization of Nanoparticles and Volatiles Present in Mainstream Hookah Smoke

Waterpipe smoking is becoming more popular worldwide and there is a pressing need to better characterize the exposure of smokers to chemical compounds present in the mainstream smoke. We report real-time measurements of mainstream smoke for carbon monoxide, volatile organic compounds and nanoparticle size distribution and chemical composition using a custom dilution flow tube. A conventional tobacco mixture, a dark leaf unwashed tobacco and a nicotine-free herbal tobacco were studied. Results show that carbon monoxide is present in the mainstream smoke and originates primarily from the charcoal used to heat the tobacco. Online measurements of volatile organic compounds in mainstream smoke showed an overwhelming contribution from glycerol. Gas phase analysis also showed that very little filtration of the gas phase products is provided by the percolation of mainstream smoke through water. Waterpipe smoking generated high concentrations of 4-100 nm nanoparticles, which were mainly composed of sugar derivatives and especially abundant in the first 10 min of the smoking session. These measured emissions of volatiles and particles are compared with those from a reference cigarette (3R4F) and represent the equivalent of the emission of one or more entire cigarettes for a single puff of hookah smoke. Considerations related to the health impacts of waterpipe smoking are discussed.

Differences in puff topography, toxicant exposure, and subjective response between waterpipe tobacco smoking men and women

Waterpipe tobacco smoking (WTS) exposes users to toxicants in much greater amounts than a cigarette. Little is known about how gender affects WTS toxicant exposure and subjective response. Data from three WTS clinical laboratory studies were combined for analysis. Participants (N = 99; 38 women) completed a 45-min WTS session where they smoked a waterpipe ad libitum. Puff topography was measured throughout, and plasma nicotine concentration, expired air carbon monoxide (CO), and subjective responses were measured pre- and post-WTS. There was a gender effect for total puff volume with men inhaling a greater smoke volume, on average (M = 59.9 L, SD = 40.7), compared with women (M = 38.8 L, SD = 27.8; p < .01). Men had greater post-WTS mean plasma nicotine concentrations (M = 10.0 ng/ml, SD = 7.1) compared with women (M = 6.9 ng/ml, SD = 5.2; p < .05). Post-WTS expired air CO was not associated with gender (men M = 27.6 ppm, SD = 18.9; women M = 22.7 ppm, SD = 17.0, ns). Relative to men, women had higher post-WTS scores for subjective measures of "nauseous," "dizzy," "nervous," "headache," and "heart pounding." Men and women are exposed to toxicants during WTS, and men may achieve higher nicotine exposure than women, likely resulting from differences in smoke inhaled. However, similar post-WTS expired air CO between men and women and higher ratings of negative subjective responses among women may indicate that factors beyond puff topography may impact toxicant exposure and subjective response to WTS. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

[Biomarkers of Smoking - Which Cut-Off Values Should be Used?]

Biomarkers of Smoking - Which Cut-Off Values Should be Used? Abstract. Verification of smoking status by means of biomarkers is important for treatment decisions of patients with smoking-related diseases. Cotinine is currently the best biomarker to document nicotine consumption. A low cost alternative method to determine smoking status is by measurement of carboxyhemoglobin (CO-Hb) in the exhaled breath. The main disadvantage of CO-Hb is the short half-life. The appropriate cut-off value for active nicotine consumption in Switzerland is 50 ng/ml or higher cotinine in the urine or 10 ng/ml and 12 ng/ml in serum and saliva, respectively. CO-Hb levels greater than 2 % indicate smoking with high probability, levels above 3 % with very high probability.