Tar in cigarette

Decker, C., A. Girardet, P. Golaz, and R. Regamey A multiple automatic apparatus for the estimation of nicotine and tar in cigarette smoke Mitt. Gebiete Lebensm. 

Polycychc aromatic hydrocarbons (PAHs) are carcinogens produced by the thermal breakdown of organic materials. These are widely distributed in both food and the environment, and are some of the principal carcinogens in cigarette tar and air pollution. Of over 20 PAHs isolated, benzopyrene and quinoline compounds are the most commonly encountered in foods, particularly those which are broiled or fried (111). Shellfish living in petroleum contaminated waters may also contain PAHs (112). 

X-Ray irradiation of quartz or silica particles induces an electron-trap lattice defect accompanied by a parallel increase in cytotoxicity (Davies, 1968). Aluminosilicate zeolites and clays (Laszlo, 1987) have been shown by electron spin resonance (e.s.r.) studies to involve free-radical intermediates in their catalytic activity. Generation of free radicals in solids may also occur by physical scission of chemical bonds and the consequent formation of dangling bonds , as exemplified by the freshly fractured theory of silicosis (Wright, 1950 Fubini et al., 1991). The entrapment of long-lived metastable free radicals has been shown to occur in the tar of cigarette smoke (Pryor, 1987). 

Increase dehvery of nicotine relative to tar in low-yield cigarettes... 

The radicals in PM2 5 have similar EPRg-values and line shapes to the radicals found in cigarette tar (12, 18, 31, 33, 37). The cigarette tar radicals produce DNA damage that is similar to that produced by PMj 5. The cigarette tar radicals are a family of semiquinone... 

The data shown in Figures 1-4 support the suggestion that PM2 5 contains radicals that, like those in cigarette tar, can reduce oxygen to superoxide, which then forms hydrogen peroxide and, ultimately, the hydroxyl radical, as shown in reactions 1-3. Iron and copper ions, which are the transition metals most frequently found in combustiongenerated particles (44) and also are ubiquitous in biological systems, could be involved in reaction 3 ... 

In conclusion, we have shown that PMj 5 contains stable radicals that can be detected by EPR. The EPR parameters, persistence in air, and DNA-damaging capacity of the PM2 5 radicals are similar to those of the radicals in cigarette tar. Therefore, we propose that the radicals associated with PMj 5 include semiquinone-type radicals that, like the... 

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