Pyrene nitro

The human cell mutagenicities of several mono- and dinitropyrenes were determined by Busby and coworkers (1994b) in a forward mutation assay using a metabolically competent line of MCL-5 cells. Minimum detectable mutagen concentrations (MMC, in nmol ml-1 the smaller the detectable concentration, the greater the potency) were as follows 1,6-dinitropyrene, 0.8 1,8-dinitropyrene, 1.5 4-nitropyrene, 3.1 1-nitro-pyrene, 9.1. Other PACs tested, 2-nitropyrene, 1,3-dinitropyrene, and pyrene, were nonmutagens in this... 

One of the important features of the coupling reaction that was brought out by Eberson and Radner (19, 20) is that it does not work for all ArH +. In particular, the perylene and pyrene cation radicals did not couple with N02. Reaction of the pyrene-dimer cation radical, (pyrene)2 +PF6 , with N02, for example, gave mainly tarry materials and less than 1% of 1-nitro-pyrene (19, 20). Eberson and Radner (19, 20) concluded that only cation... 

Ciccioli, P., A. Cecinato, E. Brancaleoni, M. Frattoni, and P. Zacchei, Formation and Transport of 2-Nitrofluoranthene and 2-Nitro-pyrene of Photochemical Origin in the Troposphere, J. Geophys. Res., 101, 19567-19581 (1996). 

Pitts, J. N., Jr., J. A. Sweetman, B. Zielinska, A. M. Winer, and R. Atkinson, Determination of 2-Nitrofluoranthene and 2-Nitro-pyrene in Ambient Particulate Organic Matter Evidence for Atmospheric Reactions, Atmos. Environ., 19, I60I-I608 (1985b). 

Figure 5. MECC chromatogram of I,4-dinitronaphthalene(A), l-nitronaphthalene(B), 9-nitroanthracene(C), and I-nitro-pyrene(D).

Negative chemical ionization high-resolution gas chroma-tography/mass spectrometry with on-column injection (NCI HRGC/MS) provides sensitivity and selectivity for the detection of nitro-aromatics. The limit of detection is approximately 50 pg for the mono-nitro-aromatics and di-nitro-pyrenes in the full mass scan data acquisition mode. The limit of detection can be improved, if necessary by using selected ion monitoring techniques. 

Figure 2 Chromatograms of GC MS-MS analyses of emissions from a diesel engine (upper panel) and from an ambient air samples (lower panel) under similar conditions. The product ion m/z 216 corresponds to HFB-derivatized 1-AP, whereas the product ion m/z 225 corresponds to the derivatized deuterated internal standard D9-I -AP (upper panel). The lower panel shows nine different products of which one was identified as 1-NP (4), presumably deriving from combustion sources. Four other peaks were tentatively identified (by cochromatography with a reference standard) as 3-nitrofluoranthene (1), 4-nitro-pyrene (2), 2-nitrofluoranthene (3), and 2-nitropyene (5), presumably primarily from atmospheric origin. The four remaining peaks (in the product ion trace m/z 244) did not coelute with available reference compounds.

U.S. certifiable nitro, pyrene, thioindigoid, and carbon colour additives for cosmetic use... 

Nitro polycyclic aromatic hydrocarbons are environmental contaminants which have been detected in airborne particulates, coal fly ash, diesel emission and carbon black photocopier toners. These compounds are metabolized Tn vitro to genotoxic agents through ring oxidation and/or nitroreduction. The details of these metabolic pathways are considered using 4-nitrobiphenyl, 1- and 2-nitronaphthalene, 5-nitro-acenaphthene, 7-nitrobenz[a]anthracene, 6-nitro-chrysene, 1-nitropyrene, 1,3-, 1,6- and 1,8-dinitro-pyrene, and 1-, 3- and 6-nitrobenzo[a] pyrene as examples ... 

Compared to the extensive data that have been obtained on the mutagenicity of nitro PAHs in S. typhimurium, relatively little is known about the metabolism of these compounds in this organism. Messier et al. (67) reported that incubation of 1-nitropyrene with S. typhimurium TA98 yielded 1-aminopyrene and 1-acetylaminopyrene as major and minor metabolites, respectively. The reduction of 1-nitropyrene was slow and was accompanied by a slow formation of DNA adducts. When incubations were conducted with the nitroreductase-deficient strain, TA100 F50, both the extent of 1-amino-pyrene formation and DNA binding decreased. Howard ej al. (71,115) also found reduction of 1-nitropyrene to 1-aminopyrene in strains TA98, TA1538 and ATCC 14028. 

The presence of a nitro substituent can enhance the intramolecular charge transfer in the excited state dramatically, so that the normal trans-to-cis isomerization of l-[2(4-nitrophenyl)ethenyl]pyrene in cyclohexane is completely suppressed74 in polar solvents such as acetonitrile (equation 66). 

Fluorescent cellulose triacetate membranes were prepared by incorporation of pyrene-butyric acid (219), and were applied to in situ detection of ground water contamination by explosives, based on fluorescence quenching by the nitro groups LOD 2 mg/L of DNT (220) and TNT (221) and 10 mg/L for RDX (276) the response follows the Stern-Volmer law for DNT and TNT442. 

In a solution containing oxygen, photolysis yields a mixture of 6,12-, 1,6-, and 3,6-diones. Nitration by nitrogen dioxide forms 6-nitro-, 1-nitro-, and 3-nitrobenzo[a]pyrene. When benzo [a] pyrene in methanol (1 g/L) was irradiated at 254 nm in a quartz flask for 1 h, the solution turned pale yellow. After 2 h, the solution turned yellow and back to clear after 4 h of irradiation. After 4 h, 99.67% of benzo[a]pyrene was converted to polar compounds. One of these compounds was identified as a methoxylated benzo[a]pyrene (Lu et al, 1977). A carbon dioxide yield of 26.5% was achieved when benzo [a] pyrene adsorbed on silica gel was irradiated with light (A, >290 nm) for 17 h (Freitag et al, 1985). 

FIGURE 10.12 Absorption spectra in methanol of benzo[a]pyrene and its 1-, 3-, and 6-nitro derivatives (adapted from Pitts et al., 1978). 

Members of another class of powerful direct mutagens, four nitroazabenzo[a]pyrene derivatives, were identified by Sera and co-workers (1994) in the basic fraction of extracts of diesel exhaust and in ambient POM. Structures and direct mutagenic activities on strains TA98 and YG1024 (-S9 mix) of the 1- and 3-nitro-6-azabenzo[a]pyrenes and the 1- and 3-nitro-6-azabenzo[a]pyrene-7V-oxides are shown in Table 10.21 (Sera et al., 1992 Fukuhara et al., 1992). They have been measured in ambient air in Fukuoka, Japan, at concentrations of 1.1, 1.2, 0.8, and 0.3 ng/g, respec-... 

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