Thirdhand Exposures to Tobacco-Specific Nitrosamines through Inhalation, Dust Ingestion, Dermal Uptake, and Epidermal Chemistry.

Tobacco-specific nitrosamines (TSNAs) are emitted during smoking and form indoors by nitrosation of nicotine. Two of them, '-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), are human carcinogens with No Significant Risk Levels (NSRLs) of 500 and 14 ng day, respectively. Another TSNA, 4-(methylnitrosamino)-4-(3-pyridyl) butanal (NNA), shows genotoxic and mutagenic activity .

Tobacco-specific and combustion pollutants in settled house dust in Malta.

Aim: Most of the carcinogenic pollutants coming from tobacco smoking or other combustion processes tend to accumulate in settled house dust (SHD) over time. This study evaluated the load of these pollutants in smokers and non-smokers' houses from relatively fresh SHD collected in five different districts on the island of Malta.

Methods: An improved, efficient extraction method to obtain three fractions from a 200 mg of SHD was developed.

Determination of 4-(Methylnitrosamino)-1-(3-Pyridyl)-1-Butanone (NNK) arising from tobacco smoke in airborne particulate matter.

The most important tobacco-specific nitrosamine found in cigarette smoke and formed in ageing smoke after cigarettes are extinguished is 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). It is formed from nitrosation of nicotine, under particular conditions both in indoor and outdoor environments. NNK has been classified as a potent lung carcinogen which is expected to be found primarily in the particle-phase and to be stable in particulate matter.

3-Ethenylpyridine Measured in Urine of Active and Passive Smokers: A Promising Biomarker and Toxicological Implications.

In studies of tobacco toxicology, including comparisons of different tobacco products and exposure to secondhand or thirdhand smoke, exposure assessment using biomarkers is often useful. Some studies have indicated that most of the toxicity of tobacco smoke is due to gas-phase compounds. 3-Ethenylpyridine (3-EP) is a major nicotine pyrolysis product occurring in the gas phase of tobacco smoke.

Ubiquitous atmospheric contamination by tobacco smoke: Nicotine and a new marker for tobacco smoke-derived particulate matter, nicotelline.

Second Hand Smoke (SHS) has always been primarily linked with indoor pollution. To date nicotine was the favoured marker for SHS alongside measurements of particulate matter (PM) levels. As nicotine is mainly found in the gas-phase and reactive in the outdoor environment it is not ideal as a marker for the SHS-driven particulate component in PM.

Characterization of Nicotine Salts in 23 Electronic Cigarette Refill Liquids.

Introduction: Many electronic cigarette manufacturers have begun offering liquids containing "nicotine salts," which are formed when an acid is mixed in a solution with free-base nicotine. Type of salt could play a significant role in the abuse liability of electronic cigarette liquids. As a first step to understanding nicotine salts, this study sought to identify the types of acids present in 23 commercially available electronic cigarette liquids.

Vascular endothelial function is impaired by aerosol from a single IQOS HeatStick to the same extent as by cigarette smoke.

Background: Heated tobacco products (also called 'heat-not-burn' products) heat tobacco at temperatures below that of combustion, causing nicotine and other compounds to aerosolise. One such product, IQOS from Philip Morris International, is being marketed internationally with claims of harm reduction. We sought to determine whether exposure to IQOS aerosol impairs arterial flow-mediated dilation (FMD), a measure of vascular endothelial function that is impaired by tobacco smoke.

Synthesis and pharmacology of new psychoactive substance 5F-CUMYL-P7AICA, a scaffold- hopping analog of synthetic cannabinoid receptor agonists 5F-CUMYL-PICA and 5F-CUMYL-PINACA.

Synthetic cannabinoid receptor agonists (SCRAs) are a dynamic class of new psychoactive substances (NPS), with novel chemotypes emerging each year. Following the putative detection of 5F-CUMYL-P7AICA in Australia in 2016, the scaffold-hopping SCRAs 5F-CUMYL-PICA, 5F-CUMYL-PINACA, and 5F-CUMYL-P7AICA were synthesized and characterized by nuclear magnetic resonance (NMR) spectroscopy, gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-quadrupole time-of-flight-MS (LC-QTOF-MS). Since little is known of the pharmacology of 7-azaindole SCRAs like 5F-CUMYL-P7AICA, the binding affinities and functional activities of all compounds at cannabinoid type 1 and type 2 receptors (CB and CB , respectively) were assessed using tritiated radioligand competition experiments and fluorescence-based plate reader membrane potential assays.

Nicotine Delivery and Vaping Behavior During E-cigarette Access.

Objective: To characterize vaping behavior and nicotine intake during e-cigarette access.

Methods: Thirteen adult e-cigarette users had 90 minutes of videotaped access to their usual e-cigarette. Plasma nicotine was measured before and every 15 minutes after the first puff; subjective effects were measured before and after the session.

An Electronic Cigarette Vaping Machine for the Characterization of Aerosol Delivery and Composition.

Introduction: Characterization of aerosols generated by electronic cigarettes (e-cigarettes) is one method used to evaluate the safety of e-cigarettes. While some researchers have modified smoking machines for e-cigarette aerosol generation, these machines are either not readily available, not automated for e-cigarette testing or have not been adequately described. The objective of this study was to build an e-cigarette vaping machine that can be used to test, under standard conditions, e-liquid aerosolization and nicotine and toxicant delivery.

Nicotelline: a proposed biomarker and environmental tracer for particulate matter derived from tobacco smoke.

Particulate matter (PM) derived from tobacco smoke contains numerous toxic substances. Since the PM and gas phase of tobacco smoke may distribute differently in the environment and substances in them may have different human bioavailability, multiple tracers and biomarkers for tobacco smoke constituents are desirable. Nicotelline is a relatively nonvolatile alkaloid present in tobacco smoke, and therefore, it has the potential to be a suitable tracer and biomarker for tobacco smoke-derived PM.

Elimination kinetics of the tobacco-specific biomarker and lung carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol.

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is tobacco specific and has a longer half-life than other tobacco biomarkers studied thus far. An accurate measurement of the NNAL half-life is important for optimal use to assess exposure to tobacco smoke. We determined the half-life of NNAL in urine in eight daily smokers on a clinical research ward and in five occasional smokers in a real-life environment.