2017 Volume 52 Issue 4 Pages 118-128
15 organic tracer compounds were analyzed at 3-hr intervals of PM2.5 samples collected by a PTFE tape filter during a high concentration event on December 9 and 10, 2015, in Nagoya. Compounds indicating primary emission burning from biomass, such as levoglucosan, and plastics, such as terephthalic acid, showed a similar temporal variation in the PM2.5 concentration which had peaks during the nights of 9 and 10 December. However, some organic tracer compounds originating from a secondary formation in the atmosphere, such as malic acid, showed a peak only on December 10. The primary emission sources contributed to the high concentration event of PM2.5, because the averaged weight fractions of the primary emission tracers relative to the PM2.5 concentration showed a similar variation to the PM2.5. However, those of the secondary formation tracers did not increase during the evening of 9 December, and only those of both succinic acid and 3-hydroxyglutaric acid showed a peak at midnight on 10 December. These results indicated different contributions of the primary emission and secondary formation to the high concentration event of PM2.5 during the observation period of this study. A higher time-resolution analysis of organic tracer compounds is a powerful tool to reveal factors causing high concentration events with a large temporal variation.
