Elements in Aerosol at Hokkaido
OTSUKA Hideyuki, NIWA Shinobu, and AKIYAMA Masayuki
Hokkaido Institute of Environmental Sciences, Kita19 Nishi12 Kita-ku, Sapporo, Hokkaido, Japan 060-0819
Including Fe with that has serious role in breathing and photosynthesis, many elements are essential for life. On the other hand, many elements have toxicity when those are extremely concentrated. And the cancer-causing elements give us a due risk in proportion to its concentration. In addition, it become clear that atmospheric suspended particulate matter become toxic when this particulate size is smaller to sub micrometer. Moreover, it is worried about the integrated effects of metal components on human health. Accordingly, it is very important to estimate the behavior of metal components in aerosol during long-term. Furthermore, it can be calculated the source attribution of aerosol when the composition of metal components is monitored in ambient air and emission sources. Therefore, we are investigating about aerosol and these components during long-term in some background and urban area over Hokkaido for estimating the effects of local source and long-range transported. From our results, it is suggested that the transported air pollution including the yellow sand phenomena, from the Asian continent and Honshu Island of Japan, influence in east-end background areas like cape Ochiishi. In particular, the concentrations of Al and Fe are increased when an air mass flowed in from the Asian continent. The tendency becomes more remarkable since 2000, caused by high frequency of the transportation of yellow sand. In addition, in while the majority of metal components show lower concentration in Ochiishi than in Rishiri according the distance from the continent, some elements show a different tendency. This suggests that the influences of each local emission can not be ignored.
Keywords: aerosol, back trajectory, background area, elements, suspended particulate matter