A three dimensional Eulerian grid model for a long-range transportation of air pollutants was used to evaluate the amounts and the source-receptor relationships of sulfate and nitratedepositions in East Asia. The analytical domain was divided into 6 regions (5 countries and the others). Contribution of deposition to receptors from each country sources and sources contribution to total deposition in each country in 1990 were estimated. Furthermore, the area including Japan was divided into 5 regions and seasonal source contribution to deposition in each region was evaluated.
10896 Gg.S of SO_x and 2886 Gg.N of NO_x were disharged, and 8885 Gg.S (81.6%) of sulfate and 2347 Gg.N (81.9%) of nitrate were deposited in the domain. The ratios between wet and dry depositions were 67% and 33% for sulfate and 56% and 44% for nitrate respectively. The large amount of sulfate and nitrate were deposited in China, and the deposition flux in South Korea and Taiwan were relatively large among East Asian countries. In Japan, the contribution of domestic anthropogenic sources to deposition of sulfate was estimated as 36.6%, and the contribution of volcanic source and Chinese source were very large. Contribution of abroad sources to deposition of sulfate and nitrate in Japan was relatively high in Winter and very low in Summer. Contribution of abroad sources to deposition in the coastal area of the Sea of Japan was especially high in Winter.

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Hourly measurements of nine C₂-C₅ species were made for a period of 15 months, in the center of Osaka city, Japan. The measurements were done by an automatic system consisted of a sample preconcentrator and gas chromatograph. The number of samples obtained was 8007, which corresponds to 81.2% of all potential measurements.
The concentrations of all components were high in early winter and low in summer. The C₂H₄ concentration was the highest amont the nine hydrocarbons while C₃H₆ showed the lowset concentration throughout the year, and was rarely detected in summer. For C₄-C₅ hydrocarbons concentrations, there were small annually variations in their concentrations. Regular diurnal patterns of hydrocarbons were observed, which were caused from emissions and meteorological effects. From the characteristic of their diurnal variations, three separate groups could be seen within the characteristic of their diurnal variations, three separate groups could be seen within the nine hydrocarbons;(1) C₂H₆ and C₃H₈, (2) C₂H₄, C₂H₂ and C₃H₆, and (3) C₄ and C₅ hydrocarbons. Each hydrocarbons ratio to measured nine hydrocarbons were also examined. The significant difference were presented by different wind direction, which reflect characteristics of the source area and time progress from their sources to the monitoring point. A characteristic common to all wind direction was the increase of C₄-C₅ ratio in summer. This phenomenon was correlated with ambient temperature indicating stronger emission of higher molecular hydrocarbons in summer.

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Acid deposition has emerged as great environmental issues of increasing concern in China. Although air pollution at South-Fujian was not severe compared with heavily polluted area, such as Chongqing and Guiyang, where precipitation of relatively high acidity was observed. In order to grasp the relation of atmospheric acidity induced by atmospheric aerosol with rainwater acidity in the district, various aerosol samples were collected in the urban and suburban area of Xiamen, Quanzhou and Zhangzhou cities in summer, 1992 and spring, 1993 and their physical and chemical characterizations were done. Then, several pollution characteristics at South-Fujian were found out. The pollution due to atmospheric aerosol was not serious, and contribution of anthropogenic sources to it was relatively low. However, contents of nitrate and sulfate ions were much higher than those of ammonium and calcium ions. Thus, the relatively high acidity and low-buffering ability of the atmospheric aerosol must be one of the important causes to induce the acidification of precipitation at South-Fujian.

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The purpose of this paper is to examine countermeasures for exhaust prevention of organic solvents at a given print shop in preparation for its reconstruction.
First, the composition and concentration of exhaust gaseous organic solvents and the woking environment of the print shop were investigated. The composition of the organic solvents was ethyl acetate, isopropyl alcohol and toluene. The total concentration of the exhaust gas was 448 ppm, which is over the Tokyo Metropolitan standard regulation value (total concentration of the three components should be 200 ppm or less). The maximum total concentration in the working environment was 762 ppm.
A bench-scale removal experiment with activated carbon adsorptive deodorization apparatus was conducted on the actual exhaust gas of the print shop by using two kinds of activated carbon.
The breakthrough time was defined as the time when the total concentration in the outlet gas of the deodrization apparatus came to 10 ppm. The breakthrough time for the granular activated carbon was 38 hr for a bed height of 260 mm and a contact time of 1.3 sec, while that for the pelletized activated carbon was 29 hr for a bed height of 330 mm and a contact time of 1.65 sec.

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The purpose of this paper is to examine countermeasures for exhaust prevention of organic solvents at a given print shop in preparation for its reconstruction.
Experiment on the removal of organic solvents with a bench-scale catalytic oxidative deodorization apparatus was performed on the actual exhaust gas of the print shop. The relation between the reaction temperature and the removal efficiency, with space velocity (SV) as the parameter, in four kinds of catalysts were investigated. The removal efficiency of platinum catalyst (catalyst A) for ethyl acetate and that of manganese plus copper catalyst (catalyst C) for toluene were low.
The catalyst which showed the highest removal efficiency was a combination of catalyst A (platinum) and catalyst C (manganese plus copper). Removal efficiency was nearly 100% under conditions of SV = 33, 000 hr^-1 and reaction temperature of 20°C
Taking these results into consideration, the exhaust gas was treated by catalytic oxidative deodorization method when a new print shop was constructed. The results were as follows: the average concentration of the inlet exhaust gas was 528 ppm, the removal efficiency of the catalytic oxidative deodorization apparatus was 97.9-98.7% at a reaction temperature of 20°C, and the concentration in the working environment was 120.9 ppm.
All data were satisfactory to meet the initial purpose.

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In order to evaluate the influences of The Great Hanshin-Awaji Earthquake, which happened on 17 Jan. 1995, on the atmospheric environment, six heavy metals which were monthly measured from Dec. 1994 through Jan. 1996 in the ten sampling sites were analyzed.
In Kobe, Ashiya and Takaraduka city, which had been damaged heavily by the earthquake, ratio of the each concentration to the monthly average during five years before the earthquake was standardized with the ratio of contrasted sampling sites, then the standardized ratios before and after the earthquake were compared.
Consequently, the ratio of Zn, Pb and Cd increased notably from Jan. to Mar. 1995 and the concentrations were 1.6 to 2.0 times larger than those of common year, whereas the ratio of Fe, Mn and Ni was smaller than these elements.
The fact that the ratio of fine particles such as Zn, Pb and Cd increased notably indicates that the particles were produced principally by combustion process and the field incineration of wastes such as houses collapsed by the earthquake was one of the factors influenced on the increase of these heavy metal concentrations.

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Poisoning accident by sarin occurred on June 27, 1994, in Matsumoto City of Nagano Prefecture. A visible damage was observed clearly in the plants at the accident site. Brown spotted damage spread from the circumference to center in the leaf of Houttuynia cordata Thunberg. Observation of injured leaf H. cordata and analysis of chemical substances extracted with water from the leaf were carried out in order to clear up the causes of the damage. Also, leaves were exposed to hydrogen fluoride and comparative examination was carried out.
The result showed that H. cordata was damaged with gases of halogen compounds, and F^- was detected in the water extract of injured leaves, so, cause substance was estimated to be hydrogen fluoride.

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The purpose of this paper is to examine a method to improve the working environment and to decrease the volume of deodorization apparatus exhaust at a given print shop.
For these purposes, we installed the hoods which were fitted over one-color gravure printing press and two-color gravure printing press. It is estimated that the minimum flow rate of exhaust air in the hoods to satisfy the maximum allowable concentration (147 ppm) of organic solvents is 1, 000 m³/hr for a one-color gravure printing press and 1, 100 m³/hr for a two-color gravure printing press. If all of the printing presses are in operation, the total flow rate of exhaust air and the total concentration of exhaust gas are estimated to be 10, 400 m³/hr and about 690 ppm, respectively.

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