Polycyclic aromatic hydrocarbons regions

An appreciation of the extent to which invertebrate species may be exposed to such chemicals comes from considering the effects of complex mixtures. In the North Atlantic ecosystem alone, hundreds of pollutant chemicals have been identified. These include metals, synthetic and chlorinated organics and polycyclic aromatic hydrocarbons. Over 300 aromatic hydrocarbons have been detected in some regions of the Chesapeake Bay, and high concentrations of PCBs have been... 

Methods for the synthesis of the biologically active dihydrodiol and diol epoxide metabolites of both carcinogenic and noncarcinogenic polycyclic aromatic hydrocarbons are reviewed. Four general synthetic routes to the trans-dihydrodiol precursors of the bay region anti and syn diol epoxide derivatives have been developed. Syntheses of the oxidized metabolites of the following hydrocarbons via these methods are described benzo(a)pyrene, benz(a)anthracene, benzo-(e)pyrene, dibenz(a,h)anthracene, triphenylene, phen-anthrene, anthracene, chrysene, benzo(c)phenanthrene, dibenzo(a,i)pyrene, dibenzo(a,h)pyrene, 7-methyl-benz(a)anthracene, 7,12-dimethylbenz(a)anthracene, 3-methylcholanthrene, 5-methylchrysene, fluoranthene, benzo(b)fluoranthene, benzo(j)fluoranthene, benzo(k)-fluoranthene, and dibenzo(a,e)fluoranthene. 

The Bay Region Theory of Polycyclic Aromatic Hydrocarbon Carcinogenesis... 

Boehm, P.D. and J.W. Farrington. 1984. Aspects of the polycyclic aromatic hydrocarbon geochemistry of recent sediments in the Georges Bank region. Environ. Sci. Technol. 18 840-845. 

Smith, J.D., J.Y. Hauser, and J. Bagg. 1985. Polycyclic aromatic hydrocarbons in sediments of the Great Barrier Reef region, Australia. Mar. Pollut. Bull. 16 110-114. 

Yan, L.S. 1985. Study of the carcinogenic mechanism for polycyclic aromatic hydrocarbons — extended bay region theory and its quantitative model. Carcinogenesis 6 1-6. 

M. Shou, F. J. Gonzalez, H. V. Gelboin, Stereoselective Epoxidation and Hydration at the K-Region of Polycyclic Aromatic Hydrocarbons by cDNA-Expressed Cytochromes P450 1A1, 1A2, and Epoxide Hydrolase , Biochemistry 1996, 35, 15807 - 15813. 

Bodzek, D K. Luks-Betlej, and L. Warzecha, Determination of Particle-Associated Polycyclic Aromatic Hydrocarbons in Ambient Air Samples from the Upper Silesia Region of Poland, Atmos. Environ., 27A, 759-764 (1993). 

The K-region of a polycyclic aromatic hydrocarbon is typified by the 9,10-bond of phenanthrene. According to the Schmidt-Pullman electronic theory, an unsubstituted K-region is a requirement for carcinogenic activity see A. Pullman and B. Pullman, La Cancerisation par les Substances Chimiques et la Structure Moleculaire, Masson, Paris, 1955. 

Initially, particular attention was focused on the epoxides of the so-called K region. As in the case of benzo [a] pyrene and certain other polycyclic aromatic hydrocarbons, these were more carcinogenic than the parent compound. The K region had attracted particular interest, as it is electronically the most reactive portion of the polycyclic aromatic hydrocarbon molecule. However, with other carcinogenic polycyclic aromatic hydrocarbons, this was not found to be the case. It now seems that the ultimate carcinogen is an epoxide of a dihydrodiol metabolite, where the epoxide is adjacent to the so-called bay region (Fig. 7.2). 

Sayer JM, Whalen DL, Jerina DM. Chemical strategies for the inactivation of bay-region diol-epoxides, ultimate carcinogens derived from polycyclic aromatic hydrocarbons. Drug Metab Rev 1989 20 155. 

An early theory linking the structure of polycyclic aromatic hydrocarbons with carcinogenesis is the K-region theory of Pullman and Pullman,197,198 according to which (1) carcinogenic activity in aromatic hydrocarbons is determined by the existence of an active K-region, and (2) if the molecule... 

Fernandez P, Grimalt JO, Vilanova RM (2002) Atmospheric gas-particle partitioning of polycyclic aromatic hydrocarbons in high mountain regions of Europe. Environ Sci Technol 36 1162-1168... 

Vibration spectroscopy is also able to measure the concentration of ion radicals (by estimation of the band intensities). Moreover, the IR intensities of some bands in the fingerprint region for organic ion radicals may be much larger than the intensities of the bands for the neutral parent molecules. The examples are polycyclic aromatic hydrocarbons or linear polyenes and their ion radicals. The vibration patterns of the intensity-carrying modes are closely related to the electronic structure of the ion radicals (Torii et al. 1999 and references therein). 

Heit M, Tan Y, Klusek C, et al. 1981. Anthropogenic trace elements and polycyclic aromatic hydrocarbon levels in sediment cores from two lakes in the Adirondack acid lake region. Water Air Soil Pollut 15 441-464. 

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