Seasonal variability of 1-chloropyrene on atmospheric particles and photostability in toluene.
The occurrence of a mutagenic compound, 1-chloropyrene (Cl-Py), in extracts of ambient particulate matter at an urban site in Japan has been investigated. Samples were collected with a high-volume air sampler for 24 h periods over the course of 1 week in winter (February), spring (May), summer (August), and autumn (November) 2002. The Cl-Py levels showed seasonal variation, ranging from 2.4 pg/m(3) (summer) to 18.9 pg/m(3) (winter). This variation would indicate that the lower temperatures in winter results in an increased distribution of Cl-Py from vapor phase to the particle phase. In addition, there is also the possibility that ambient Cl-Py is emitted from seasonal sources or is susceptible to photodegradation by sunlight, or both. The photodegradation of Cl-Py in a laboratory experiment was conducted to simulate the compound's fate on airborne particle surfaces. The degradation of Cl-Py proceeded by a first-order reaction with a rate constant of 0.72 h(-1). In the presence of a radical sensitizer, 9,10-anthraquinone (AQ), the photodegradation rate of Cl-Py was elevated in comparison with the rate in the absence of AQ. In addition, the dechlorination of Cl-Py (i.e., the formation of Py) occurred in the presence of AQ.
Institute for Environmental Sciences, University of Shizuoka, 52-1, Yada, Shizuoka 422-8526, Japan. ooura@smail.u-shizuoka-ken.ac.jp
Takeshi
T
Ohura
Atsushi
A
Kitazawa
Takashi
T
Amagai
D000393:Air Pollutants / Q000032:analysis*; D000880:Anthraquinones / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D008401:Gas Chromatography-Mass Spectrometry; D007564:Japan; D044367:Phase Transition; D010782:Photolysis; D011721:Pyrenes / Q000032:analysis*; D012621:Seasons; D013050:Spectrometry, Fluorescence; D013696:Temperature; D014050:Toluene / Q000737:chemistry
D000393:Air Pollutants; D000880:Anthraquinones; D011721:Pyrenes; C040345:1-chloropyrene; D014050:Toluene