Atmospheric Formation of Hydroxynitrofluoranthene from Photochemical Reactions of 2-Nitrofluoranthene

Abstract

The formation of hydroxynitrofluoranthene (OHNF) via photochemical reactions of 2-nitrofluoranthene (2-NF) was demonstrated using a UV irradiation system. The photoreaction of 2-NF in acetonitrile/water (3/1, v/v) gave a product that was hydroxynitro-substituted. Moreover, we detected an OHNF isomer, which was found in the 2-NF photoreaction products, in soluble organic fractions of ambient airborne particles collected in Kanazawa, Japan. The atmospheric concentration of the OHNF isomer was estimated to be less than 2 fmol m⁻³, which was comparable to that of 1-hydroxy-3-nitropyrene, but lower than that of 1-hydroxy-6-nitropyrene by a factor of 10. The results suggests that atmospheric OHNF is partly formed via secondary formation processes, i.e., photochemical reactions of 2-NF appear to have a significant effect on the occurrence of OHNF in the atmosphere.

Key Words:

• 2-nitrofluoranthene
• airborne particles
• atmospheric secondary formation
• hydroxynitrofluoranthene
• photochemical reaction

Acknowledgments

This research was supported by MEXT/JSPS Grant-in-Aid for Scientific Research (21200031, 22510010) and the Environment Research and Technology Development Fund (RF-0905) of the Ministry of the Environment, Japan.