70021-98-6Relevant articles and documents
Atmospheric heterogeneous reactions of benzo(a)pyrene
Cazaunau,Menach, K. Le,Budzinski,Villenave
experimental part, p. 1151 - 1170 (2011/02/16)
This experimental study deals with heterogeneous reactions of benzo(a)pyrene (BaP) with ozone, nitrogen dioxide and hydroxyl radicals. BaP was adsorbed on silica particles chosen here as a model of mineral atmospheric particles. Compound extractions were assisted by focused microwave and analyses were performed by gas chromatography coupled with mass spectroscopy in single ion monitoring mode. Pseudo-first order rate constants were obtained from the fit of experimental decays of particulate-BaP concentration versus reaction time. Second order rate constants were determined considering the different oxidant gaseous concentrations except for the case of hydroxyl radicals where only a pseudo-first order rate constant was proposed. Values obtained at room temperature are (2.1±0.5)×10-15 cm3 molecule-1 s-1 for (BaP + ozone), (5.8±1.4) ×10-16 cm3 molecule-1 s-1 for (BaP + nitrogen dioxide) and (3.4±0.8)×10-2 s -1 for (BaP + OH) reactions. Products have only been investigated for the NO2 and the OH (in the presence of NOx) reactions. 1-, 3- and 6-nitrobenzo(a)pyrenes were detected as degradation products and quantified. Reaction rate constants for product formation are (3.7±0.9)×10-16 cm3 molecule-1 s-1 for 6-NBaP, (2.2±0.6)×10-17 cm 3 molecule-1 s-1 for 1-NBaP and (5.3±1.3)×10-17 cm3 molecule-1 s-1 for 3-NBaP. 1-, 3- and 6-nitroBaP account respectively for approximately 5%, 12% and 83% of total nitrated species. If in thepresence of only nitrogen dioxide, BaP was totally degraded within few minutes, only 20 to 25 % of the initial BaP led to nitrated compounds when reacting with OH (in the presence of NOx). by Oldenbourg Wissenschaftsverlag.
Mutagenic nitrated benzo[a]pyrene derivatives in the reaction product of benzo[a]pyrene in NO2-air in the presence of O3 or under photoirradiation
Ishii, Satoko,Hisamatsu, Yoshiharu,Inazu, Koji,Kobayashi, Takaaki,Aika, Ken-ichi
, p. 1809 - 1819 (2007/10/03)
In order to clarify the contribution of nitrated products to the direct-mutagenic activity of products of the reactions of benzo[a]pyrene in NO2-air under various conditions, heterogeneous reactions of BaP deposited on filter in the air containing 10 ppm of NO2 have been conducted in dark or under photoirradiation. The reaction products have been analyzed by gas chromatography and mutagenicity of the products fractionated by preparative HPLC was assayed for Salmonella typhimurium strains TA98 and YG1024 in the absence of S9 mix. 3,6-dinitrobenzo[a]pyrene and 1,3-dinitrobenzo[a]pyrene, which are strong direct-acting mutagens, largely contributed to the total direct-acting mutagenicity of the dark reaction products in NO2-air. On the other hand, both the dark reaction in the presence of O3 and the photoreaction in NO2-air resulted in the formation of much smaller amounts of nitrobenzo[a]pyrenes than that observed in the dark reaction in the absence of O3. These results show that the contribution of other direct-acting mutagens to the total direct-acting mutagenicity of the products in these reactions should be considered. Benzo[a]pyrene lactones were identified in a highly mutagenic fraction of the products of the dark reaction in the presence of O3 and photoreaction and a nitrobenzo[a]pyrene lactone was also identified in a highly mutagenic fraction of the dark reaction products in the presence of O3. Nitrated oxygenated benzo[a]pyrene derivatives such as nitrobenzo[a]pyrene lactone were considered to largely contribute to direct-acting mutagenicity of the products of the dark reaction in the presence of O3 and photoreaction. (C) 2000 Elsevier Science Ltd.
Synthesis, Spectral Analysis, and Mutagenicity of 1-, 3-, and 6-Nitrobenzopyrene
Chou, M. W.,Heflich, R. H.,Casciano, D. A.,Miller, D. W.,Freeman, J. P.,et al.
, p. 1156 - 1161 (2007/10/02)
The mutagenic environmental pollutants 1-, 3-, and 6-nitrobenzopyrene were synthesized.Nitration of 7,8,9,10-tetrahydrobenzopyrene with sodium nitrate in trifluoroacetic acid and acetic anhydride at ambient temperature gave a mixture of 1-, 3-, and 6-nitro-7,8,9,10-tetrahydrobenzopyrene, which was separated by chromatography.Dehydrogenation of the isolated nitrotetrahydrobenzopyrenes with 2,3-dichloro-4,5-dicyano-1,6-benzoquinone produced 1-, 3-, and 6-nitrobenzopyrene in high yield.Comparison of the spectral data of these compounds with those obtained from direct nitration of benzopyrene confirmed that 1- and 3-nitrobenzopyrenes are indeed the minor products of the latter reaction.This confirmation also verifies that 1- and 3-nitrobenzopyrene were the minor nitrated products of benzopyrene formed in model air atmospheres.The 1-, 3-, and 6-nitrobenzopyrene were mutagenic in Salmonella typhimurium tester strains TA98 and TA100 in the presence of a mammalian microsomal (S9) activating system.Both 1- and 3-nitrobenzopyrene, but not 6-nitrobenzopyrene, were also direct-acting mutagens in these strains.However, only 6-nitrobenzopyrene exhibited weak mutagenic activity when tested in Chinese hamster ovary cells, while only 3-nitrobenzopyrene produced a concentration-dependent decrease in cellular survival.
