Objective To provide researchers an extensive characterization of the SPECTRUM variable nicotine research cigarettes. Methods Data on cigarette physical properties, nicotine content, harmful and potentially harmful constituents in the tobacco filler was compiled. Results Data on physical properties, concentrations of menthol, nicotine and minor alkaloids, tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons, ammonia, and toxic metals in the filler tobacco for all available varieties of Spectrum research cigarettes are provided. The similarity in the chemistry and physical properties of SPECTRUM cigarettes to commercial cigarettes renders them acceptable for use in behavioral studies. Baseline information on harmful and potentially harmful constituents in research tobacco products, particularly constituent levels such as minor alkaloids that fall outside typical ranges reported for commercial, provide researchers with the opportunity to monitor smoking behavior and to identify biomarkers that will inform efforts to understand the role of nicotine in creating and sustaining addiction. Conclusions Well characterized research cigarettes suitable for human consumption are an important tool in clinical studies for investigating the physiological impacts of cigarettes delivering various levels of nicotine, the impact of reduced nicotine cigarettes on nicotine addiction, and the relationship between nicotine dose and smoking behavior.

As the technology of electronic nicotine delivery systems (ENDS), including e-cigarettes, evolves, assessing metal concentrations in liquids among brands over time becomes challenging. A method for quantification of chromium, nickel, copper, zinc, cadmium, tin, and lead in ENDS liquids using triple quadrupole inductively coupled plasma mass spectrometry was developed. The method’s limits of detection (LODs) were 0.031, 0.032, 3.15, 1.27, 0.108, 0.099, 0.066 µg/g for Cr, Ni, Cu, Zn, Cd, Sn, and Pb respectively. Liquids analyzed were from different brands and flavors of refill bottles or single-use, rechargeable, and pod devices from different years. Scanning electron microscopy with energy dispersive spectroscopy further evaluated the device components’ compositions. Refill liquids before contacting a device were below lowest reportable levels (LRL) for all metals. Copper and zinc were elevated in liquids from devices containing brass. Cadmium was

Since 2006 the domestic popularity and sales of electronic cigarettes (i.e., electronic nicotine delivery systems or ENDS) have grown rapidly. Although the constituents of the aerosol produced by ENDS have been previously investigated, differences in puff regimens and aerosol trapping schema in published literature often complicate result comparisons and data interpretation. As the ENDS product designs continue to evolve, there is a critical need to develop and validate robust methodologies for laboratory testing, appropriate aerosol generation and trapping media required for accurate determinations of ENDS aerosol metals deliveries. A simple, high metals purity, fluoropolymer trap was developed and validated that meets standard machine puffing regimen (CORESTA Recommended Method 81) specifications and exhibits negligible acid extractable metal backgrounds. Using a standard machine puffing regimen in combination with a fluoropolymer condensation trap, aerosol was generated and collected from select ENDS devices for analysis of chromium, nickel, copper, zinc, cadmium, tin, and lead with triple quadrupole inductively coupled plasma mass spectrometry. Devices tested spanned a range of commercial products, including flavored variants of JUUL pods, refillable tank systems, rechargeable cartridges, and single-use ENDs devices. Results showed that for aerosols generated under a fixed puffing regimen (50 puffs/collection), metal concentrations ranged from below the detection limits (LOD) to 614 ng copper and 339 ng zinc per 10 puffs. Cadmium concentrations were below LOD for all devices tested. Device specific aerosol levels of Sn and Pb ranged from below LOD to low nanogram levels. Cr and Ni were transported in aerosols at levels equivalent to, or slightly higher than in mainstream cigarette smoke using a standard smoking regimen. The generally lower levels of specific metals, Cd and Pb, transmitted in ENDS aerosols compared to mainstream cigarette smoke reflect possible reduction of harm for smokers who substitute the use of ENDS as cessation devices in place of smoking cigarettes.

High-quality, accurate data on liquid contents and aerosol emissions from electronic nicotine delivery systems (ENDS, e.g., e-cigarettes) are crucial to address potential health concerns as these devices evolve and mature. Metals are an important class of ENDS constituents that merit attention as they have various health implications. Proper sampling, handling and aerosol trapping materials are essential to generate accurate quantitative metal data and to reduce the likelihood of inaccurate results originating from inappropriate collection vessels and materials that contribute to high background levels. Published methods that meet these criteria were applied to the analyses of chromium, nickel, copper, zinc, cadmium, tin and lead in liquid and aerosol from mint/menthol and tobacco flavors of currently popular pod-based devices from three manufacturers. Metal concentrations from pods that had not been used for generating aerosol ranged from below our lowest reportable level to 0.164 µg/g for Cr, 61.3 µg/g for Ni, 927 µg/g for Cu, 14.9 µg/g for Zn, 58.2 µg/g for Sn and 2.56 µg/g for Pb. Cadmium was included in our analyte panel and was not present above detection limits in liquid or aerosol. Aerosol metal concentrations (using a 55-mL puff) ranged from below our lowest reportable level to 29.9 ng/10 puffs for Cr, 373 ng/10 puffs for Ni, 209 ng/10 puffs for Cu, 4,580 ng/10 puffs for Zn, 127 ng/10 puffs for Sn and 463 ng/10 puffs for Pb. Our results showed some metal delivery from all the products examined and highly variable metal levels between manufacturer, brand and package.

The popularity of electronic cigarettes (electronic nicotine delivery systems or ENDS) has grown rapidly over the past decade. With the continued evolution of ENDS, and the arrival of newer replaceable pod devices on the market, it is prudent to examine their emissions to help determine potential health risks to the user. Metal containing particles were examined in aerosol from several pod-based devices from three manufacturers that offer flavored liquids in their respective products. Previous ENDS metal emissions studies focused on the total toxic metal concentrations in aerosols and have suggested that the principal sources are oxidized internal metal components that are in contact with the liquid. Most metal oxides have limited solubility and it is likely that some metal content in ENDS aerosol may present as particles rather than dissolved forms. Examining the composition and number of particles in the ENDS aerosols is important because inhaled metal oxide particles cause pulmonary inflammation. Chronic inhalation of ENDS aerosol may lead to inflammatory cell activation in the lungs. Therefore, this study was designed to measure metal oxide particle concentrations and sizes in ENDS aerosols from select pod-based systems. Aerosol samples were generated with pod liquids (tobacco, mint or menthol) from devices produced by three manufacturers using CORESTA Recommended Method 81 parameters with a high purity fluoropolymer aerosol trap. Particle sizes for chromium, iron, nickel, copper, zinc, tin, and lead oxides were measured in triplicate using single particle inductively coupled plasma-mass spectrometry and dynamic light scattering. A novel aspect of these measurements included using dual element particle analysis to infer particle source component material. Particle concentrations in aerosols from the devices were variable between devices and from pod to pod, ranging from no detectable chromium and zinc containing particles in aerosol from some pods to 222,000 lead containing particles per 10 puffs from individual pods.