Nicotine Delivery of a Menthol-Flavored Heat-not-Burn Tobacco Product During Directed Use.

Introduction: IQOS was authorized by the U.S. Food and Drug Administration (FDA) as a modified-risk tobacco product.

Influence of Tobacco Variety and Curing on Free Radical Production in Cigarette Smoke.

Introduction: Cigarette smoke contains highly reactive free radicals thought to play an important role in tobacco smoke-induced harm. Previously, large variations in free radical and toxicant output have been observed in commercial cigarettes. These variations are likely because of cigarette design features (paper, filter, and additives), tobacco variety (burley, bright, oriental, etc.

Tobacco Nitrate and Free Radical Levels in the Mainstream Smoke of US Cigarette Brands.

Tobacco nitrate levels have been known to impact the levels of toxicants such as polyaromatic hydrocarbons and tobacco-specific nitrosamines (TSNAs) produced during smoking. Recent work in our group showed that the intrinsic nitrate levels in individual tobacco varieties also have a large influence on the formation of gas-phase (GP) free radicals in the mainstream smoke of cigarettes produced with a single tobacco variety. As tobacco nitrate content is a potential target for future regulatory policies, we investigated whether the levels of GP free radicals in the smoke from commercially available cigarettes is also dependent on the nitrate content in the corresponding tobacco blends.

The effects of reduced nicotine content cigarettes on biomarkers of nicotine and toxicant exposure, smoking behavior and psychiatric symptoms in smokers with mood or anxiety disorders: A double-blind randomized trial.

Background: The U.S. Food and Drug Administration and the government of New Zealand have proposed a reduction of the nicotine content in cigarettes to very low levels.

Effects of tobacco nitrate content on free radical levels in mainstream smoke.

Tobacco smoke free radicals play an important role in the development of smoking related adverse health effects. We previously reported that gas phase (GP) radicals vary greatly by cigarette brand and tobacco variety and are highly correlated with levels of NNK in smoke. Since NNK production in tobacco is dependent on nitrate, we proposed that GP radical production may also be associated with tobacco nitrate content.

Pilot randomized controlled trial evaluating the effect of random nicotine delivery on cigarettes per day and smoke exposure.

Background: Many smokers report attempting to quit each year, yet most relapse, in part due to exposure to smoking-related cues. It is hypothesized that extinction of the cue-drug association could be facilitated through random nicotine delivery (RND), thus making it easier for smokers to quit. The current study aimed to evaluate the effects of RND on smoking cessation-related outcomes including cigarettes per day (CPD) and exhaled carbon monoxide (CO).

Evaluating electronic cigarette cytotoxicity and inflammatory responses in vitro.

Introduction: Cigarette smoking poses many health risks and can cause chronic obstructive pulmonary disease (COPD), cardiovascular disease, cancer of the lung and other organs. Smokers can substantially reduce their risks of these diseases by quitting, but nicotine addiction makes this difficult. Alternatives, such as electronic cigarettes (e-cigarettes), may provide a similar dose of nicotine, but expose users to fewer toxic chemicals than traditional cigarettes and may still be harmful especially for dual users, therefore, we sought to develop bioassays that can assess the potential toxicity and inflammatory response induced by e-cigarette liquids (e-liquids) with and without flavors.

Lipoxygenase catalyzed metabolites derived from docosahexaenoic acid are promising antitumor agents against breast cancer.

Docosahexaenoic acid (DHA) is known to inhibit breast cancer in the rat. Here we investigated whether DHA itself or select metabolites can account for its antitumor action. We focused on metabolites derived from the lipoxygenase (LOX) pathway since we previously showed that they were superior anti-proliferating agents compared to DHA; 4-OXO-DHA was the most potent.

Switching to Progressively Reduced Nicotine Content Cigarettes in Smokers With Low Socioeconomic Status: A Double-Blind Randomized Clinical Trial.

Introduction: The Food and Drug Administration issued an advanced notice of proposed rulemaking for setting a product standard for nicotine levels in cigarettes, with an emphasis on minimally or non-addicting very low nicotine content (VLNC).

Methods: A 33 week, two-arm, double-blind randomized trial conducted in Hershey, Pennsylvania, USA and Washington, DC, USA included adult daily cigarette smokers (≥5 cigarettes per day) with less than a college degree, and who had no plans to quit within the next six months. Participants were randomized to either reduced nicotine content (RNC) study cigarettes tapered every three weeks to a final VLNC (0.

Free Radical Production and Characterization of Heat-Not-Burn Cigarettes in Comparison to Conventional and Electronic Cigarettes.

With conventional cigarettes, the burning cone reaches temperatures of >900 °C, resulting in the production of numerous toxicants and significant levels of highly reactive free radicals. In attempts to eliminate combustion while still delivering nicotine and flavorings, a newer alternative tobacco product has emerged known as "heat-not-burn" (HnB). These products heat tobacco to temperatures of 250-350 °C depending on the device allowing for the volatilization of nicotine and flavorants while potentially limiting the production of combustion-related toxicants.

Free Radical and Nicotine Yields in Mainstream Smoke of Chinese Marketed Cigarettes: Variation with Smoking Regimens and Cigarette Brands.

Free radicals and nicotine are components of cigarette smoke that are thought to contribute to the development of smoking-induced diseases. China has the largest number of smokers in the world, yet little is known about the yields of tobacco smoke constituents in different Chinese brands of cigarettes. In this study, gas-phase and particulate-phase free radicals as well as nicotine yields were quantified in mainstream cigarette smoke from five popular Chinese brands and two research cigarettes (3R4F and 1R6F).

An Electronic Aerosol Delivery System for Functional Magnetic Resonance Imaging.

Background: Public health concerns over the addictive potential of electronic cigarettes (e-cigs) have heightened in recent years. Brain function during e-cig use could provide an objective measure of the addictive potential of new vaping products to facilitate research; however, there are limited methods for delivering e-cig aerosols during functional magnetic resonance imaging (fMRI). The current study describes the development and feasibility testing of a prototype to deliver up to four different e-cig aerosols during fMRI.

Nicotine Absorption Profile Among Regular Users of a Pod-Based Electronic Nicotine Delivery System.

This case series characterizes nicotine absorption among adults who regularly use a pod-based electronic nicotine delivery system.

Nicotine absorption during electronic cigarette use among regular users.

Background: The capability of electronic cigarette devices (e-cigs) to deliver nicotine is key to their potential to replace combustible cigarettes. We compared nicotine delivery and subjective effects associated with the use of two classes of e-cigarettes and cigarettes.

Methods: 14 e-cigarette users were instructed to vape their own e-cigarette device every 20 seconds for 10 minutes while blood was drawn at 1, 2, 4, 6, 8, 10,12, and 15 minutes after initiating vaping.

Pharmacokinetic Profile of Spectrum Reduced Nicotine Cigarettes.

Introduction: Spectrum research cigarettes have been developed with varying nicotine content for use in studies evaluating the effects of a regulatory policy reducing the permissible nicotine content in cigarettes. This study aimed to characterize the nicotine pharmacokinetic profile of Spectrum cigarettes.

Methods: Twelve daily smokers attended four sessions and had blood nicotine, exhaled carbon monoxide, and subjective effects measured before and after smoking either a single cigarette of their preferred brand or high (10.

Emissions of Free Radicals, Carbonyls, and Nicotine from the NIDA Standardized Research Electronic Cigarette and Comparison to Similar Commercial Devices.

E-cigarettes (e-cigs) are a diverse and continuously evolving group of products with four generations currently in the market. The National Institute on Drug Abuse (NIDA) standardized research e-cigarette (SREC) is intended to provide researchers with a consistent e-cig device with known characteristics. Thus, we conducted laboratory-based characterizations of oxidants and nicotine in aerosols produced from SREC and other closed-system, breath-activated, commercially available e-cigs (Blu and Vuse).

Effects of Charcoal on Carbonyl Delivery from Commercial, Research, and Make-Your-Own Cigarettes.

Previous literature has shown that adding charcoal to cigarette filters can have varying effects on the delivery of toxic carbonyls depending on filter design, amount of charcoal, and puffing profiles. However, these studies have relied on either comparisons between commercially available charcoal and noncharcoal filtered cigarettes or experimental modification of filters to insert a charcoal plug into existing cellulose acetate filters. Make-your-own (MYO) cigarettes can help obviate many of the potential pitfalls of previous studies; thus, we conducted studies using commercial charcoal cigarettes and MYO cigarettes to determine the effects of charcoal on carbonyl delivery.

Free Radical, Carbonyl, and Nicotine Levels Produced by Juul Electronic Cigarettes.

Introduction: Free radicals and carbonyls produced by electronic cigarettes (e-cigs) have the potential to inflict oxidative stress. Recently, Juul e-cigs have risen drastically in popularity; however, there is no data on nicotine and oxidant yields from this new e-cig design.

Methods: Aerosol generated from four different Juul flavors was analyzed for carbonyls, nicotine, and free radicals.

Effect of Charcoal in Cigarette Filters on Free Radicals in Mainstream Smoke.

The addition of charcoal in cigarette filters may be an effective means of reducing many toxicants from tobacco smoke. Free radicals are a highly reactive class of oxidants abundant in cigarette smoke, and here we evaluated the effectiveness of charcoal to reduce free radical delivery by comparing radical yields from commercially available cigarettes with charcoal-infused filters to those without and by examining the effects of incorporating charcoal into conventional cigarette filters on radical production. Commercial cigarettes containing charcoal filters produced 40% fewer gas-phase radicals than did regular cellulose acetate filter cigarettes when smoked using the International Organization of Standardization (ISO, p = 0.

Correction to Reduced nicotine content cigarettes in smokers of low socioeconomic status: study protocol for a randomized control trial.

The title of the original publication [1] had an error; furthermore there were errors in Fig. 2. The corrected version of the title and of Fig.

A Survey of Nicotine Yields in Small Cigar Smoke: Influence of Cigar Design and Smoking Regimens.

Introduction: Although the popularity of small cigar brands that resemble cigarettes, including both little cigars (LC) and filtered cigars (FC), has been on the rise, little is known about the delivery of nicotine from these products. Our objective was to determine the nicotine yields of small cigars in comparison to cigarettes.

Methods: Nicotine yields from LC, FC, and 3R4F and 1R6F research cigarettes were determined from mainstream smoke generated on a smoking machine under the International Organization of Standardization (ISO) and Canadian Intense (CI) methods.

Reduced nicotine content cigarettes in smokers of low socioeconomic status: study protocol for a randomized control trial.

Background: The Family Smoking Prevention and Tobacco Control Act gave the Food and Drug Administration jurisdiction over the regulation of all tobacco products, including their nicotine content. Under this act, a major strategy to reduce harm from cigarette tobacco is lowering the nicotine content without causing unintended adverse consequences. Initial research on reduced nicotine content (RNC) cigarettes has shown that smokers of these cigarettes gradually decrease their smoking frequency and biomarkers of exposure.

Brand variation in oxidant production in mainstream cigarette smoke: Carbonyls and free radicals.

Oxidative stress/damage resulting from exposure to cigarette smoke plays a critical role in the development of tobacco-caused diseases. Carbonyls and free radicals are two major classes of oxidants in tobacco smoke. There is little information on the combined delivery of these oxidants across different cigarette brands; thus, we set out to measure and compare their levels in mainstream smoke from popular US cigarettes.

Variation in Free Radical Yields from U.S. Marketed Cigarettes.

Free radicals in tobacco smoke are thought to be an important cause of smoking-induced diseases, yet the variation in free radical exposure to smokers from different brands of commercially available cigarettes is unknown. We measured the levels of highly reactive gas-phase and stable particulate-phase radicals in mainstream cigarette smoke by electron paramagnetic resonance (EPR) spectroscopy with and without the spin-trapping agent phenyl-N-tert-butylnitrone (PBN), respectively, in 27 popular US cigarettes and the 3R4F research cigarette, machine-smoked according to the FTC protocol. We find a 12-fold variation in the levels of gas-phase radicals (1.

Influence of Obesity on Breast Density Reduction by Omega-3 Fatty Acids: Evidence from a Randomized Clinical Trial.

Preclinical data indicate that omega-3 fatty acids (n-3FA) potentiate the chemopreventive effect of the antiestrogen (AE) tamoxifen against mammary carcinogenesis. The role of n-3FA in breast cancer prevention in humans is controversial. Preclinical and epidemiologic data suggest that n-3FA may be preferentially protective in obese subjects.