In Japan, acid rain has been recognized to be significant since drizzling injured people's eyesand caused skin irritation during the rainy seasons of 1973 to 1975 in the Kanto and Chubu Districts. Later, the acid rain has become one of a most global environmental problem, so, precipitation chemistry data were obtained in Phase-1 Study of Acid Precipitation Survey over Japan from 1984 to 1988 by Japan Environment Agency. Annual mean pH value over Japan was about 4.6 (4.5 4.7) and the value was not changed significantly in the past decade. The acidity of rainwater was caused by H₂SO₄ and HNO₃ mainly, but in the urban areas, the acidity was neutralized by alkaline species, such as NH₃ and Ca²⁺ species. We notice that the precipitation chemistry data obtained in many sites are useful to make clear the effects of acid rain on terrestrial ecosystems.

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We have been investigated the atmospheric concentration of polynuclear aromatic hydrocarbons (PAHs) in the Kitakyushu district, one of the industrial area in Japan.
Airborne particulate samples were collected on a glass fiber filters by use of a high-volume air sampler from November 1980 to March 1989 in the western part of the Kitakyushu district.
Three PAHs; Benzo [a] pyrene, Benzo [ghi] peryrene and Benzo [k] fluoranthene wereanalyzed by a reversed phase high-performance liquid chromatograph equipped wtih a spectrofluorometer. The results obtained are as follows;
(1) Yearly average concentrations of airborne particulate ranged from 77.9 to 54.5 pg/m³, and the high concentration was observed in the spring and the autumn and low in the summer. Through out the measurements, the highest concentration was 461.6μg/m³ on April 1988.
(2) The yearly mean of PAHs concentrations has decreased since 1985, and the benzo [a] pyrene concentration at present is less than 1μg/m³. Seasonal variations of PAHs concentrations show a tendency to rise in the winter and decline in the summer.
(3) A significant correlation was observed not only between the concentration of airborne particulate and these of PAHs, but also between the concentrations of the three PAHs.

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Dry deposition velocities for sulfur dioxide over the terrestrial and nearby oceanic regions in Japan were computed. Seasonal variations of surface roughness scale length, atmospheric stability and regidences for sulfur uptake were estimated from consideration of land use characteristics and the biological status of vegetation. Average deposition velocities for warm and cold season conditions for 80 km mesh grid cells were presented. Estimated deposition velocities of terrestrial regions in the warm season are about 0.5 cm/s, in the cold season, about 0.4 cm/s and in the snow season, less than 0.2 cm/s. The examples clearly illustrate that spatial and temporal variations in dry deposition velocities are important and cannot betignoted ro predict long term deposition patterns in Japan Islands.

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An application of non-suppressor ion chromatography (NS-IC) equipped with high efficient oven which controlled the flow system containing the detector cell to the determination of anions in rain water was examined.
It was found that the NS-IC method was suitable for rapid within 6 minutes and simultaneous determination of three anions (SO₄^2-, NO₃^-, Cl^-) with mobile phase (2.5 mM phthalic acid-2.4 mM tris (hydroxymethyl)-aminomethane), flow rate 1.5 ml/min and column temperature 40°C.
By adjusting sample solution to the same composition of mobile phase and measuringthe peak area, the NSIC method was superior with respect to reproducibility and detection limit.

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For CO₂ as global warming substance, CO₂ emissions from diesel and LPG vehicle were culculated from the emission factors and the statistical fuel marketing amount of these vehicles. And adding the emission from gasoline vehicle, total CO₂ emission from vehicles in Japan was calculated.
Theoretical CO₂ emission factors of diesel and LPG vehicles are respectively 2.61 (kg/l) and 3.09 (kg/kg), but the factors calculated from actual running mode were respectively 2.34 (kg/l) and 3.01 (kg/kg), affected by particulates and so on in exhaust gas. The CO₂ emissions calculated by these factors and the statistical fuel marketing amount were 50, 996×10³ ton and 4, 527×10³ ton respectively, and the total CO₂ emission added the emission of gasoline vehicle was 144, 077×10³ ton. The total CO₂ emission showed the samll increase almost every year, especially the emission from diesel vehicle showed the largest increase.

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A routine based air quality monitoring was made for airborne particulate matter at Seoul, Korea. Methods of sampling and analysis of National Air Surveillance Network, Japan were applied to this monitoring. Samplings at the Seoul station were started with a high volume air sampler (Hi-Vol) in May 1986 and a low volume air sampler (Lo-Vol) was added in April 1987. Total Suspended Particles (TSP) and their carboneous, anion and metal components were analyzed for Hi-Vol samples, while multi-elemental neutron activation analysis was made for 31 elements in Lo-Vol samples. In this paper, all data at Seoul prior to March 1989 are presented with some comments on the Hi-Vol data. The contribution of the carbonaceous material to TSP was 26%, and that of the elemental carbon from diesel exhaust emission was 15%, respectively. The atmospheric Pb concentrations in Seoul were 0.20-0.78μg/m³ and higher than those of Tokyo, Japan, by a factor of 5.4; this may be caused by the use sof leaded gasoline for automobiles. The annual variation of TSP concentrations was almost constant at higher levels than those of Japanese cities during the monitoring period.

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[in Japanese]

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