Aromatic hydrocarbons benzo pyrene

Sander and wise have proposed a test method to determine the bonding chemistry used to prepare octadecylsiloxane column packings based on the relative retention of three polycyclic aromatic hydrocarbons, benzo[a]pyrene (BaP), phenanthro-phenanthrene (PhPh), and l,2 3,4 5,6 7,8-tetrabenzonaphthalene (TBN) eluted with the mobile phase acetonitrile-water (85 15) [52,67,199,210]. On monomeric phases the test solutes elute in the... 

Fig. 5 Typical deformations detected in 96 hpf zebrafish embryos exposed at the indicated concentrations of the carcinogenic polycyclic aromatic hydrocarbons Benzo[a]Pyrene (b) and Benazo [k]Fluoranthene (c), or to the reportedly nontoxic AhR-ligand (3-naphthofiavone (d). A nonexposed, normal specimen is shown in (a). Arrows indicate (a) pericardial edema, (b) malformation of the lower jaw, (c) malformation of the tail, (tf) color of the yolk, and (e) coagulation...

Maximum residue levels in certain foods are set for the following contaminants nitrate, my cotoxins (aflatoxins, ochratoxin A, pamlin, deoxynivalenol, zearalenone, fumonisins, T -2 and HT-2-toxin), metals (lead, cadmium, mercury, inorganic tin), 3-MCPD (3-monochloro-propane-l,2-diol), dioxins and PCBs, and polycyclic aromatic hydrocarbons (benzo(a)pyrene) (EC 2007c). 

Formation of a dihydrodiol by hydration of epoxide groups can be an important detoxication process in that the product is often much less reactive to potential receptors than is the epoxide. However, this is not invariably the case because some dihydrodiols may undergo further epoxidation to form even more reactive metabolites. As shown in Figure 7.3, this can happen with benzo(a)pyrene 7,8-epoxide, which becomes oxidized to carcinogenic benzo(a)pyrene 7,8-diol-9,10-epoxide. The parent polycyclic aromatic hydrocarbon benzo(a)pyrene is classified as a procarcinogen, or precarcinogen, in that metabolic action is required to convert it to a species, in this case benzo(a)pyrene 7,8-diol-9,10-epoxide, which is carcinogenic as such. 

Metabolization of the polycyclic aromatic hydrocarbon benzo[a]pyrene by a non-white rot fungus (Fusarium solani) in a batch reactor. Polycyclic Aromatic Compounds, 22, 87-97. 

Polycyclic aromatic hydrocarbons Benzo(a)pyrenes Methylcholanthrene Dimethylbenz(a)anthracene Solvents Benzene Heavy metals Beryllium Manganese Nickel Cadmium Platinum Air pollutants Ozone... 

Pentachlorophenol (PCP) absorption in porcine skin was tripled when exposure to PCP was preceded by preexposure to the lipophilic polynuclear aromatic hydrocarbon benzo[a]pyrene.]15l... 

Bos RP, Theuws JL, Leijdekkers Ch. M. 1984b. The presence of the mutagenic polycyclic aromatic hydrocarbons benzo[a]pyrene and benz[a]anthracene in creosote Pj. Mutat Res 130 153-158. 

Benz[fl]anthracene (see Polycyclic Aromatic Hydrocarbons) Benzo[h]fluoranthene (see Polycychc Aromatic Hydrocarbons) Benzo[y]fluoranthene (see Polycyclic Aromatic Hydrocarbons) Benzo[fc]fluoranthene (see Polycyclic Aromatic Hydrocarbons) Benzo[fl]pyrene (see Polycyclic Aromatic Hydrocarbons) Benzotrichloride Bromodichloromethane... 

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). 

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... 

Aerobic, Anaerobic, and Combined Systems. The vast majority of in situ bioremediations ate conducted under aerobic conditions because most organics can be degraded aerobically and more rapidly than under anaerobic conditions. Some synthetic chemicals are highly resistant to aerobic biodegradation, such as highly oxidized, chlorinated hydrocarbons and polynuclear aromatic hydrocarbons (PAHs). Examples of such compounds are tetrachloroethylene, TCE, benzo(a)pyrene [50-32-8] PCBs, and pesticides. 

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). 

Fig. 42 Chromatogram of polycyclic aromatic hydrocarbons on caffeine-impregnated precoated silica gel 60 HPTLC plates with concentrating zone (Merck). The following can be recognized in increasing Rf value. — 1. benzo(ghi)perylene, 2. indeno(l,2,3-cd)pyrene, 3 benzo(a)pyrene, 4. benzo(b)fluoranthene, 5. benzo(k)fluoranthene, 6. fluoranthene.

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]. 

Some examples of different types of hydrocarbons are given in Figure 9.1. Nonaromatic compounds without ring structure are termed aliphatic, whereas those with a ring structure (e.g., cyclohexane) are termed alicyclic. Aromatic hydrocarbons often consist of several fused rings, as in the case of benzo[a]pyrene. 

Warshawsky D, T Cody, M Radike, R Reilman, B Schumann, K LaDow, J Schneider (1995) Biotransformation of benzo[a]pyrene and other polycyclic aromatic hydrocarbons and heterocyclic analogues by several green algae and other algal species under gold and white light. Chem-Biol Interact 97 131-148. 

Juhasz AL, R Naidu (2000) Bioremediation of high molecular weight polycyclic aromatic hydrocarbons a review of the microbial degradation of benzo[a]pyrene. Int Biodet Biodeg 45 57-88. 

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