Occurrence and photostability of 3-nitrobenzanthrone associated with atmospheric particles
- 作者：Feilberg ; Anders ; Ohura ; Takeshi ; Nielsen ; Torben ; Poulsen ; Morten West Bach ; Amagai ; Takashi
- 关键词：3-Nitrobenzanthrone ; Polycyclic aromatic compounds ; Aerosols ; Photodegradation ; Sources in ambient air
- 刊名：Atmospheric Environment
- 出版年：2002
- 期刊代码：11_13522310
- 类别：env
- 出版时间：August, 2002
- 卷：36
- 期：22
- 页码：3591-3600
- 文件大小：156 K
摘要
The occurrence of the carcinogenic and extremely mutagenic compound, 3-nitrobenzanthrone, in extracts of ambient particulate matter has been investigated at a semi-rural sampling location. A total of seventeen 24-h samples and fourteen 12-h samples were analyzed for their content of 3-nitrobenzanthrone. 3-Nitrobenzanthrone was unambiguously detected in one-fourth of the samples in the lower pgm−3 range (mean=17.1±14.8 or 9.8±4.2pgm−3 excluding one high value), but in the majority of the samples no signal due to 3-nitrobenzanthrone was observed. By comparison with the levels of nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) and other air pollution components, it is suggested that 3-nitrobenzanthrone is a directly emitted primary pollutant and that it is not formed in the atmosphere to a significant degree. The photodegradation of 3-nitrobenzanthrone was studied in order to understand the low levels of this compound in ambient air. In the presence of a radical sensitizer, anthraquinone, the degradation rate of 3-nitrobenzanthrone is comparable to that of 1-nitropyrene (NP), a directly emitted nitro-PAH present in ambient air in significantly higher levels than 3-nitrobenzanthrone. The rate of direct photolysis is slightly smaller than that for 1NP. The conclusion of this study is that the dominant sources of 3-nitrobenzanthrone are unidentified combustion processes from which it is emitted in relatively small amounts. Accordingly, 3-nitrobenzanthrone should mainly be considered a health problem at locations close to these sources.