Abstract
Enoshima area, Kanagawa Pref. is located in the southern part of densely populated areas such as Yokohama and Tokyo, and the land-sea breeze is often observed especially in summer. Air pollutants emitted in inland area are transported by the land breeze toward the sea in the early morning, and then after the wind direction changes to the sea breeze, they are brought back to the land area. In order to investigate the chemical behaviors of organic vapor pollutants while staying in the atmosphere, measurement of organic vapor pollutants was carried out from 7: 00 to 13: 00 at the coast of Enoshima on September 11, 1990. The land-sea breeze was observed on the day, and organic vapor pollutants emitted in inland area were observed at the coast early in the morning, and chemically changed organic compounds were observed later in the morning.
Paraffins and aromatic hydrocarbons contained in exhaust gas of gasoline fuelled vehicles showed a similar trend, and ethyl acetate, which is not contained in exhaust gas of gasoline fuelled vehicles was also similar tothem. Chlorinated hydrocarbons such as 1, 1, 1-trichloroethane, trichloroethylene, tetrachloroethylene and carbon tetrachloride were contained more in the sea breeze than other organic pollutants. The concentrationsof ethylbenzene and xylenes were decreased in accordance with the respective reaction rates with OH radical, but chemical behaviors of benzene and toluene were seemed not to agree with the reactivities with OH radical. Several unidentified peaks were also observed in the chromatogram of the air sampled after the wind direction turned to the sea breeze.
