Carcinogenicity aromatic hydrocarbons

Jerina, D. M., Dansette, P. M., Lu, A. Y. H., and Levin, W. Hepatic microsomal epoxide hydrase a sensitive radiometric assay for hydration of arene oxides of carcinogenic aromatic hydrocarbons. Mol. Pharmacol. (1977) 13 342-351. 

Nesnow S. 1994. Mechanistic linkage between DNA adducts, mutations in oncogenes, and tumorigenicity of carcinogenic aromatic hydrocarbons in strain A/J mice. In Chemical mixtures and quantitative risk assessment. Abstract of the second annual HERL symposium, Nov. 7-10., Raleigh, North Carolina Health Effects Research Laboratory, U.S. Environmental Protection Agency. 

Cavalieri, E. L., S. Higginbotham, and E. G. Rogan, Dibenzo[a,/]pyrene The Most Potent Carcinogenic Aromatic Hydrocarbon, Polycyclic Aromat. Compd., 6, 177-183 (1994). 

Cavalieri E.L. and Rogan, E.G. (2002) Fluoro substitution of carcinogenic aromatic hydrocarbons models for understanding mechanisms of metabolic activation and of oxygen transfer catalyzed by cytochrome P450, in The Handbook of Environmental Chemistry, Vol. 3,... 

Herndon, W.C. and Szentpaly, L.V. (1986) Theoretical model of activation of carcinogenic polycyclic benzenoid aromatic hydrocarbons. Possible new classes of carcinogenic aromatic hydrocarbons. 

Consequently, the vast majority of SCF applications are based on CO2 near the GL critical point, with a possible admixture to support the ability for solvating dipolar components. The extraction of carcinogenic aromatic hydrocarbons and their nitro derivatives from diesel particulates by CO2 + toluene or methanol SCF can serve as an example. CO2 based SCF also helps in cleaning polyethylene from undesired polymer additives. In a similar way one can consider technologies focused on so called h q)er-coal, an extremely pure and environment friendly fuel for turbines in power plants. Recently, the first power plants based on this idea are being constructed in China. The removal of pesticides from meat, decaffeinated coffee and denicotinized cigarettes are the next society-relevant applications. Noteworthy is the h q)er-oxidation with supercritical water and bitumens extraction based on supercritical toluene. The latter system is also used for the liquefaction of coal. ... 

Hoffmann, D. and E.L. Wynder Short-term determination of carcinogenic aromatic hydrocarbons Anal. 1803. 

Since aromatic hydrocarbons are one of the chief pollutants in air, the fluoro-meter has been used by the Public Health Service [33] for determining these compounds. Fluorometry is more useful than ultraviolet spectrophotometry in pollution analysis, not only because it is more versatile, but also because it can measure the very low concentrations of hydrocarbons found in samples collected from the air. Such analyses are all the more important because some aromatic hydrocarbons are carcinogenic. One of the best known carcinogenic aromatic hydrocarbons is benzo[a]pyrene, or 3,4-benzpyrene. A very specific method for determining benzo-... 

As a result, inert and aprotic solvent toluene is suitable for the titration of weak bases in non-aqneons media as solvent, although benzene which is more carcinogenic aromatic hydrocarbon nsed widely in literature for non-aqueous titrations. The major advantage of tolnene is that it does not compete for protons with the reactant in the titrations becanse of its autoprotolysis constant approaching zero. The major disadvantages of solnbility can be removed by using small amount of amphiprotic solvents. 

The use of high-solanesol tobacco for smoking should be avoided due to the possible formation of excessive levels of carcinogenic aromatic hydrocarbons such as benzo[a]pyrene from solanesol. This is also true for nonsmoking tobacco products when fire-cured (Chamberlain et al. 1988). 

Two new routes to arene oxides of carcinogenic aromatic hydrocarbons have been reported, which employ OsO or NBS sequences to prepare the required 1,2-diol or a-bromo alcohol intermediates for epoxidation. ... 

Outside of carbon monoxide for which the toxicity is already well-known, five types of organic chemical compounds capable of being emitted by vehicles will be the focus of our particular attention these are benzene, 1-3 butadiene, formaldehyde, acetaldehyde and polynuclear aromatic hydrocarbons, PNA, taken as a whole. Among the latter, two, like benzo [a] pyrene, are viewed as carcinogens. Benzene is considered here not as a motor fuel component emitted by evaporation, but because of its presence in exhaust gas (see Figure 5.25). 

The purpose of this eornpuLer project is Lo examine several polynuclear aromatic hydrocarbons and to relate their electron density patterns to their carcinogenic activity. If nucleophilic binding to DN.A is a significant step in blocking the normal transcription process of DN.A, electron density in the hydrocarbon should be positively correlated to its carcinogenic potency. To begin with, we shall rely on clinical evidence that benzene, naphthalene, and phenanthrene... 

A large number of polycyclic aromatic hydrocarbons are known Many have been synthesized m the laboratory and several of the others are products of com bustion Benzo[a]pyrene for example is present m tobacco smoke contaminates food cooked on barbecue grills and collects m the soot of chimneys Benzo[a]pyrene is a carcinogen (a cancer causing substance) It is converted m the liver to an epoxy diol that can induce mutations leading to the uncontrolled growth of certain cells... 

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). 

The fused 3+ ring aromatics in petroleum include both cata- and peri-condensed stmctures (see Table 4, Fig. 8). The cata-condensed species are those stmctures where only one face is shared between rings, the peri-condensed molecules are those that share more than one face. The fused ring aromatics form the class of compounds known as polynuclear aromatic hydrocarbons (PAH) which includes a number of recognized carcinogens in the 4+ ring family (33). Because of the potential health and environmental impact of PAH, these compounds have been studied extensively in petroleum. 

Cancerous skin lesions of workers exposed to pitch dust undoubtedly support the behef that these lesions are caused by polynuclear aromatic hydrocarbons, although it had not been possible to demonstrate their carcinogenic action in animals more closely related to humans, such as monkeys. 

Carcinogens Cancer-producing agents Skin Respiratory Bladder/urinary tract Liver Nasal Bone marrow Coal tar pitch dust crude anthracene dust mineral oil mist arsenic. Asbestos polycyclic aromatic hydrocarbons nickel ore arsenic bis-(chloromethyl) ether mustard gas. p-naphthylamine benzidine 4-am i nodi pheny lam ine. Vinyl chloride monomer. Mustard gas nickel ore. Benzene. 

Polycyclic aromatic hydrocarbons have been classified as human carcinogens because they induce cancers in experimental animals and because smoking and exposure to mixtures of chemicals containing polycyclic aromatic hydrocarbons in the workplace increase the risk of lung cancer in exposed individuals. In experimental animals, benzo(a)pyrene induces cancer in different organs depending on the route of administration.Furthermore, exposure to polycyclic aromatic hydrocarbons commonly occurs in occupations related to traffic (use of diesel engines in transportation and railways). 

Although many of the aromatic compounds based on benzene have pleasant odors, they are usually toxic, and some are carcinogenic. Volatile aromatic hydrocarbons are highly flammable and burn with a luminous, sooty flame. The effects of molecular size (in simple arenes as well as in substituted aromatics) and of molecular symmetry (e.g., xylene isomers) are noticeable in physical properties [48, p. 212 49, p. 375 50, p. 41]. Since the hybrid bonds of benzene rings are as stable as the single bonds in alkanes, aromatic compounds can participate in chemical reactions without disrupting the ring structure. 

Dihydro-9,10-epoxyphenanthrene and related arene oxides are of considerable interest as carcinogens formed by polycyclic aromatic hydrocarbons in vivo.45 Phenanthrene oxide does not isomerize to the corresponding dibenzoxepin under thermal conditions. Photolysis of... 

Benzo[a]pyrene, a molecule with five, fused, hexagonal rings, is among the most carcinogenic of the polycyclic aromatic hydrocarbons (PAHs). Such biological activity may be related to the electronic structure of benzo[a]pyrene and its metabolites. Ionization energies of these molecules therefore have been investigated with photoelectron spectroscopy [28]. 

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