Polycychc aromatic hydrocarbons,

Difluoronaphthalene [315-52-6] is prepared from 4-fluoro-l-naphthylarnine by the Balz-Schiemann reaction. 1,4-Difluoronaphthalene is used in chemical carcinogenesis studies as a synthon for highly condensed difluoro—polycycHc aromatic hydrocarbons (273). 

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). 

In general, peroxomonosulfates have fewer uses in organic chemistry than peroxodisulfates. However, the triple salt is used for oxidizing ketones (qv) to dioxiranes (7) (71,72), which in turn are useful oxidants in organic chemistry. Acetone in water is oxidized by triple salt to dimethyldioxirane, which in turn oxidizes alkenes to epoxides, polycycHc aromatic hydrocarbons to oxides and diones, amines to nitro compounds, sulfides to sulfoxides, phosphines to phosphine oxides, and alkanes to alcohols or carbonyl compounds. 

Actual water treatment challenges are multicomponent. For example, contamination of groundwater by creosote [8021-39-4], a wood (qv) preservative, is a recurring problem in the vicinity of wood-preserving faciUties. Creosote is a complex mixture of 85 wt % polycycHc aromatic hydrocarbons (PAHs) 10 wt % phenohc compounds, including methylated phenols and the remaining 5 wt % N—, S—, and O— heterocycHcs (38). Aqueous solutions of creosote are therefore, in many ways, typical of the multicomponent samples found in polluted aquifers. 

Principal component analysis has been used in combination with spectroscopy in other types of multicomponent analyses. For example, compatible and incompatible blends of polyphenzlene oxides and polystyrene were distinguished using Fourier-transform-infrared spectra (59). Raman spectra of sulfuric acid/water mixtures were used in conjunction with principal component analysis to identify different ions, compositions, and hydrates (60). The identity and number of species present in binary and tertiary mixtures of polycycHc aromatic hydrocarbons were deterrnined using fluorescence spectra (61). 

Photochromism Based on Triplet Formation. Upon absorption of light, many polycycHc aromatic hydrocarbons and their heterocycHc analogues undergo transitions to their triplet state which has an absorption spectmm different from that of the ground state (24). In rigid glasses and some plastics, the triplet state, which may absorb in the visible, has a lifetime of up to 20 seconds. 

The poor regioselectivity of alkyne insertion in our polycychc aromatic hydrocarbon synthesis (Scheme 17) suggested to us that perhaps the palladium intermediate in that process was actually undergoing migration from one aromatic ring to the other, perhaps by a Pd(IV) hydride intermediate, to establish an equilibrium mixture of two regioisomeric arylpalladium intermediates under our reaction conditions (Scheme 18). This, indeed, appears to be true as... 

Caslavsk, J. and Kotlafikova, P. 2003, High-molecular-weight polycychc aromatic hydrocarbons in the area and vicinity of the DEZA chemical plant, Czech Republic. Polycyclic Aromat. Compd. 23 327-352. 

Fetzer, J.C. and Biggs, W.R., The use of large polycychc aromatic hydrocarbons to study retention in non-aqueous reversed-phase HPLC, Chromatographia, 27, 118, 1989. 

Jinno, K., Molecular planarity recognition for polycychc aromatic hydrocarbons in liquid chromatography, in Jinno, K. (Ed.), Chromatographic Separations Based on Molecular Recognition, Wiley-VCH, Inc., New York, 1997, p. 65. 

Wise, S.A. and Sander, L.C., Factors affecting the reversed-phase hqnid chromatographic separation of polycychc aromatic hydrocarbon isomers, J. High Resolut. Chromatogr. Chromatogr. Commun., 8, 248, 1985. 

Sander, L.C. and Wise, S.A., Effect ofphase length on column selectivity for the separation of polycychc aromatic hydrocarbons by reversed-phase hquid chromatography, Anal. Chem., 59, 2309, 1987. 

Some dietary practices are thought to contribute to cancer development (Table 21.7). For example, high-temperature cooking prodnces carcinogens such as heterocyclic amines and polycychc aromatic hydrocarbons, and storing food can allow microbial carcinogens, snch as aflatoxin, to be prodnced (see Figure 21.27). 

In the field of bioremediation, oxidoreductases are considered to be excellent biocatalysts for environmentally friendly processes. Laccases and peroxidases are widely used to treat effluents from pulp/cotton mills, food/fruit processing plants and breweries [1, 2, 37]. Laccases, peroxidases and other oxygenases are also being studied for their abihty to degrade hazardous coal substances, especially the sulfur-containing components, and in the treatment of industrial waste and contaminated soil and water in the transformation of xenobiotics, polycycHc aromatic hydrocarbons and other pollutants (biodetoxification and biodecontamination)... 

EFSA,A report from the Unit of data collection and exposure on a request from the European Commission, Findings of the EFSA data collection on polycychc aromatic hydrocarbons in food. Issued on June 29, 2007. 

SCF, European Commission, Opinion of the on the risks to human health of polycychc aromatic hydrocarbons in food (expressed on December 4, 2002). 

Polycychc aromatic hydrocarbons were epoxidized by DMD to arene oxides by Jeyaraman and Murray. ... 

SPI Division Level 3 and 4 LTTD systems have been designed and manufactured for thermal treatment of soils contaminated with polycychc aromatic hydrocarbons (PAHs), including coal tars from former manufactured gas plant (MGP) sites. When equipped with acid-scrubbing systems, these LTTD systems have been utilized in treatment of soils contaminated with a wide range of chlorinated hydrocarbons including industrial solvents and degreasers, pesticides, herbicides, and polychlorinated biphenyls (E CBs). 

Biosolids-enhanced remediation (BER) is an ex situ bioremediation technology used to treat soils contaminated with petroleum hydrocarbons and polycychc aromatic hydrocarbons. The BER technology was developed by isolating particular microorganisms with the ability to degrade the specific components of petroleum products. The technology has been applied full scale and is commercially available. 

Anthracene under Polycychc Aromatic Hydrocarbons, Two- or Three-Ring Compoimds Anhmony... 

Barnett, D. 1976. Polycychc aromatic hydrocarbons and foods. CSIRO Eood Res. Quart. 36 8-12. 

Mezey, P.G., Z. Zimpel, P. Warburton, P.D. Walker, D.G. Irvine, X.D. Huang, D.G. Dixon, and B.M. Greenberg. 1998. Use of quantitative shape-activity relationships to model the photoinduced toxicity of polycychc aromatic hydrocarbons electron density shape features accurately predict toxicity. Environ. Toxicol. Chem. 17 1207-1215. 

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

Yu, Y, T.L. Wade, J. Eang, S. McDonald, and J.M. Brooks. 1995. Gas chromatographic-mass spectrometric analysis of polycychc aromatic hydrocarbon metabohtes in Antarctic hsh (Notothenia gibberifrons) injected with Diesel Euel Arctic. Arch. Environ. Contam. Toxicol. 29 241-246. 

Section 12.17 Polycychc aromatic hydrocarbons undergo the same kind of electrophilic aromatic substitution reactions as benzene. 

Finklemann, H., Laub, R.J., Roberts, W.E., and Smith, C.A., Use of mixed phases for enhanced gas chromatographic separation of polycychc aromatic hydrocarbons. II. Phase transition behavior, mass-transfer non-equilibrium, and analytical properties of a mesogen polymer solvent with silicone diluents, in Polynuclear Aromatic Hydrocarbons, Phys. Biol. Chem. 6th Int. Symp., Cooke, M., Ed., Battelle Press, Columbus, OH, 1982, p. 275. 

Bouzige, M., V. Pichon, and M.C. Hennion. 1998. On-line coupling of immunosorbent and liquid chromatographic analysis for the selective extraction and determination of polycychc aromatic hydrocarbons in water samples at the ng F1 level. J. Chromatogr. A 823 197-210. 

Knopp, D., M. Seifert, V. Vaananen, et al. 2000. Determination of polycychc aromatic hydrocarbons in contaminated water and soil samples by immunological and chromatographic methods. Environ. Sci. Technol. 34 2035-2041. 

Nording, M., K. Freeh, Y. Persson, et al. 2006. On the semi-quantification of polycychc aromatic hydrocarbons in contaminated soil by an enzyme-linked immunosorbent assay kit. Anal. Chim. Acta 555 107-113. 

Fahnrich, K.A., M. Pravda, and G.G. Guilbault. 2003. Disposable amperometric immunosensor for the detection of polycychc aromatic hydrocarbons (PAHs) using screen-printed electrodes. Biosens. Bioelectron. 18 73-82. 

Liu, M., Q.X. Li, and G.A. Rechnitz. 1999. Flow injection immunosensing of polycychc aromatic hydrocarbons with a quartz crystal microbalance. Anal. Chim. Acta 387 29-38. 

Kamlet, M.J., Doherty, R.M., Carr, P.W., Mackay, D., Abraham, M.H., Taft, R.W. (1988) Linear solvation energy relationship. 44. Parameter estimation rules that allow accurate prediction of octanol/water partition coefficients and other solubility and toxicity properties of polychlorinated biphenyls and polycychc aromatic hydrocarbons. Environ. Sci. Technol. 22, 503-509. 

Rockne, K.J., Strand, S.E. (1998) Biodegradation of bicychc and polycychc aromatic hydrocarbons in anaerobic enrichments. Environ. Sci. Technol. 32, 3962-3967. 

Ten Hulscher, Th.E.M., van der Velde, Bruggeman, W.A. (1992) Temperature dependence of Henry s law constants for selected chlorobenzenes, polychlorinated biphenyls and polycyclic aromatic hydrocarbons. Environ. Toxicol. Chem. 11, 1595-1603. Ten Hulscher, T.E.M., Vrind, B., Van den Heuvel, H., van Noort, P., Govers, H. (2003) Influence of desorption and contact time on sediment of spiked polychlorinated biphenyls and polycychc aromatic hydrocarbons relationship with in situ distribution. Environ. Toxicol. Chem. 22, 1208-1211. 

Cai, Q.-Y, Mo, C.-H., Wu, Q.-T., Zeng, Q.-Y., Katsoyiannis, A., and Ferard, J.-E. 2007. Bioremediation of polycychc aromatic hydrocarbons (PAHs)-contaminated sewage sludge by different composting processes. Journal of Hazardous Materials, 142 535 2. 

Gigliotti, C.L., Totten, L.A., et al (2005) Atmospheric concentrations and deposition of polycychc aromatic hydrocarbons to the Mid-Atlantic East Coast Region. Environmental Science and Technology, 39(15) 5550-5559. 

PolycycHc aromatic hydrocarbons such as benzo(a)pyrene (which is present in cigarette smoke and meat cooked over charcoal), dioxin, many drugs, and substances found in plants hke St John s wort all induce the enzymes involved in the detoxication of drugs and other chemicals. The effect of this induction can be seen as an increase in the metabohsm of a drug, which therefore increases the ehmination. However, it can also increase the toxicity of a drug. This is the case with paracetamol, whose toxicity is increased in chronic alcohoHcs and in people taking certain other drugs (see pp. 54-5). 

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