open access

https://hdl.handle.net/2115/47137

Enhanced concentrations of citric acid in spring aerosols collected at the Gosan background site in East Asia

英語

East Asian aerosols

2011-09

Elsevier

Atmospheric Environment

45(30)

5266-5272

Elevated concentrations of atmospheric citric acid (range: 20-320 ng m^[-3]) were observed in total suspended particles collected at Gosan background site in Jeju Island, Korea during mid- to late April of 2007 and 2008. In order to specify the sources of citric acid, water-soluble dicarboxylic acids and related compounds were measured in the pollen sample collected at the Gosan site (Pollen_Gosan), authentic pollen samples from Japanese cedar (Pollen_cedar) and Japanese cypress trees (Pollen_cypress), and tangerine fruit produced from Jeju Island. Citric acid (2790 ng in unit mg of pollen mass) was found as most abundant species in the Pollen_Gosan, followed by oxalic acid (2390 ng mg^[-1]). Although citric acid was not detected in the Pollen_cedar and Pollen_cypress as major species, it was detected in the tangerine juice as a dominant species while malic acid was detected as major species in the tangerine peel, followed by oxalic and citric acids. Since Japanese cedar trees are planted around tangerine farms to prevent strong winds from the Pacific Ocean, citric acid that may be directly emitted from tangerine is likely adsorbed on pollens emitted from Japanese cedar and then transported to the Gosan site. Much lower malic/citric acid ratios under cloudy condition than clear condition suggest that malic acid may rapidly decompose to lower molecular weight compounds such as oxalic and malonic acids (<C4) via aqueous phase reaction in cloud during the atmospheric transport.

学術雑誌論文

Accepted Manuscript

1352-2310