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

Abstract

Free radicals and nicotine are components of cigarette smoke that are thought to contribute to the development of smokinginduced 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). Mainstream smoke was generated under International Organization of Standardization (ISO) and Canadian Intense (CI) smoking regimens using a linear smoking machine. Levels of free radicals and nicotine were measured by electron paramagnetic resonance spectroscopy (EPR) and gas chromatography with flame-ionization detection, respectively. Under the ISO puffing regimen, Chinese brand cigarettes produced an average of 3.0 ± 1.2 nmol/cig gas-phase radicals, 118 ± 44.7 pmol/cig particulate-phase radicals, and 0.6 ± 0.2 mg/cig nicotine. Under the CI puffing regimen, Chinese brand cigarettes produced an average of 5.6 ± 1.2 nmol/cig gas-phase radicals, 282 ± 92.1 pmol/cig particulate-phase radicals, and 2.1 ± 0.4 mg/cig nicotine. Overall, both gas-and particulate-phase free radicals were substantially lower compared to the research cigarettes under both regimens, whereas no significant differences were observed for nicotine levels. When Chinese brands were compared, the highest free radical and nicotine yields were found in "LL" and "BS" brands, while lowest levels were found in "YY". These results suggested that the lower radical delivery by Chinese cigarettes compared to United States reference cigarettes may be associated with reductions in oxidant-related harm.

Free Radicals in Little Cigar Mainstream Smoke and the Potential Influence of Flavoring Chemicals on Free Radical Production

“…In brief, smoke from the little cigars was passed through a CFP into a 25 mL impinger containing 4 mL of 0.05 M PBN in ice-cold tert -butylbenzene. The nitrone spin trap, PBN, has been used extensively for the detection of radical species in cigarette smoke. ,, High-purity quartz EPR tubes were filled with 200 μL of the PBN solution and deoxygenated using a freeze pump-thaw technique with a Schlenk line, as described previously. , Spectra derived from PBN radical adducts were measured using a Bruker eScan R spectrometer (Bruker-Biospin, Billerica, MA) operating in X-band. The EPR parameters were as follows: microwave frequency, 9.7 GHz; modulation frequency, 86.0 kHz; microwave power, 6.00 mW; scan range, 60 G; modulation amplitude, 2.04 G; sweep time, 5.24 s; time constant, 10.24 ms; conversion time, 10.24 ms. All measurements were carried out at room temperature (22 ± 1 °C).…”

A Comparative DFT Study on the Antioxidant Activity of Some Novel 3‐Hydroxypyridine‐4‐One Derivatives

“…They result from an imbalance between the production of oxidant derivatives and essential antioxidants of our body. Free radicals are produced during normal metabolic events or exposure to environmental oxidants such as cigarette smoke, alcohol, ionizing and UV radiations, pesticides, and ozone [1–4] . The most important endogenous mitochondrial sources of free radicals are the mitochondrial electron transport chains and nitric oxide synthase reactions [5] .…”

“…Free radicals are produced during normal metabolic events or exposure to environmental oxidants such as cigarette smoke, alcohol, ionizing and UV radiations, pesticides, and ozone. [1][2][3][4] The most important endogenous mitochondrial sources of free radicals are the mitochondrial electron transport chains and nitric oxide synthase reactions. [5] Non-mitochondrial sources of free radicals are the Fenton reaction, microsomal cytochrome P450 enzymes, peroxisomal beta-oxidation and respiratory rupture of phagocytic cells.…”