Atmospheric and precipitation samples were taken at Niigata site (urban region which is in Niigata-city) and at Kasabori site (mountains area which is in Sanjou-city) in Niigata Prefecture during the period from August, 2005 to May, 2006. Polycyclic aromatic hydrocarbon (PAHs) of 19 substances were determined by using the pressurized liquid extraction (PLE) method and GC-MS to investigate the behavior of PAHs. New collection method of combining Quartz fiber filter paper (QFP), ENVI-C18 disk (C18) and Active carbon fiber filter paper (ACFP) was employed for collecting atmospheric PAHs in this work.
The following matters have been mainly clarified from this work. (1) The atmospheric PAHs having more than 5 rings were collected by QFP for 89.8∼100 %, the PAHs having 4 rings were collected by C18 for 58.0∼72.3 %, and the PAHs having 3 rings were by ACFP for 41.6∼73.6 % (though low recovery of PAHs having 3 rings in winter). (2) The annual average concentration of PAHs is 21 ng/m3 at the urban region and 9.9 ng/m3 at the mountains area. In winter and spring, similar concentration level of total PAHs were found between at the urban region and at the mountains area. On the other hand, in summer and autumn, the concentration of total PAHs at the urban region is 4∼6 times larger than that at the mountains area. (3) PAHs amounts in precipitation increased in winter at the mountains area. (4) The PAHs composition ratio in precipitation showed two composition patterns (i.e. in case of (I) summer and autumn, (II) winter and spring) at 2 sites in Niigata Prefecture. (5) Both the concentrations of PAHs in air and those in precipitation increased in winter, but no clear correlation was observed between them by correlation analysis.