Studies and problems on the prediction of air pollutant concentration over complex terrain are discussed and the dispersion experiments conducted and the dispersion models proposed are reviewed.
According to these studies, the plume spread over complex terrain tends to become larger than that over fl at terrain. Although many dispersion models over complex terrain have been proposed to evaluate air pollutant concentration, most of them are rather facile in the treatment of plume axis and the precision of prediction is insufficient.

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In the previous paper authors presented the optimum design and quantitative evaluation of parameters of dispersion model by experimental regression analysis with orthogonal array table and Signal-Noise ratio (SN ratio).
In this paper the proposed method is applied to the dispersion experiment in Garfield area and Tochigi area by using the prediction system of pollutant dispersion in complex terrain proposed by authors.
The results are as follows:
1) The same effect as is obtained by calculations of all combinations of parameters can be obtained by much less calculations.
2) Parameters which have large contribution are atmospheric stability and pseudo resistance parameter, in addition, boundary condition in Tochigi area.
3) The SN ratio of the prediction system is -4-40 db when parameters are optimized.

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The effects of of oxidants on carotenes in plant leaves were investigated under laboratory condition or in field survey.
The plants used for controlled-chamber study were carrot (Daucus carota L.) and Ginkgo tree (Ginkgo biloba L.), both of which contain a-carotene and β-carotene. The Ginkgo and carrot were exposed to O₃ at 0.3 ppm, 6h/day for 3 days, and at 0.25 ppm, 6h/day for 2 days, respectively. In both cases, a-carotene in the leaves decreased significantly, whereas jS-carotene decreased slightly. Therefore, the reduction of the α-carotene/β-carotene ratio can be used as an indicator of O₃ in jury to the leaves.
The carotene contents and α-/β-carotene ratio in Ginkgo leaves were investigated for two years (1975-1976) in the air-polluted area (Osaka-shi and Sakai-shi). As control area Yamato highland in Nara prefecture was chosen. The Ginkgo leaves in the air-polluted area showed much more degradation of α-carotene than that of n-carotene. It was suggested that the reduction of the α-/β-carotene ratio was caused by oxidants in the air.

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In order to evaluate the atmospheric corrosion of metals in Ichihara area, Chiba prefecture, the relation between the air pollution and the corrosion of metals was investigated from August 1968 to July 1975. The weight changes of the metals were measured such as iron plate, copper plate, aluminium plate, brass plate, and galvanized iron plate. The contents of sulphur deposited on the surface of the metal and sulphur trioxide concentration in sampling area were analyzed by BaSO₄ and PbO₂ methods respectively. On the other hand, the surface roughness of metals was measured by a roughness meter. Each metal was exposed for three months in sampling area.
Results obtained are as follows:
1. The corrosion of metals exposed in atmosphere changed at sampling sites and the average weight gains of the samples increased as follows; galvanized iron plate (0.0085 g)<brass plate (0.0176 g)<copper plate (0.0232 g)<aluminium plate (0.0264 g)<iron plate (0.06289 g).
2. Copper, aluminium, and brass plates were remarkably corroded at A, B, C sites in winter than in summer, while iron and galvanized iron plates were corroded in summer than in winter.
3. The corrosion metals were compared with the air pollution. The aspect of weight gains by corrosion coincided with the distribution patterns of SO2 concentrations.
4. The weight changes of copper and aluminium plates were correlated with the concentration of SO₂ except for iron and galvanized plates in winter.
5. The degree of corrosion in atmosphere was evaluated by the surface roughness of metals corroded.

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An analytical method has been developed of elemental carbon in airborne dust samples collected on quarz fiber filters.
After organic carbon having been removed from the sample, elemental carbon was determined by use of ultimate analyzer (CHN corder).
In order to separate completely organic carbon and to prevent the loss of elemental carbon from the sample, two thermal separation methods were used:(1) heat separation method;(2) oxidation decomposition method. In the method (1), the sample was heated at 900°c for 2 min in purified He. In the method (2), the sample was heated at 390°C-410°C for 6 min in air.
It was shown from the results of residual H/C ratios in the samples that these separation methods are useful for the accurate determination of elemental carbon in airborne dust.

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The effects of flue gas temperature on dust measurement by the present JIS method were investigated in many facilities. For the test of dust collection part of type 1 combined with type 2 (the filter of type 2 is not heated), dust collection efficiency of type 1 (type 1/(typel + type 2)) greatly decreased as the flue gas temperature increased in boilers and glass melting furnaces. However, the slope of the regression line between dust concentration and flue gas temperature was different in the both facilities, it seems to be due to the composition of dust. Consequently, chemical composition of dust emitted from the above-mentioned two facilities was analysed. The composition of dust showed a clear difference between type 1 and type 2 at boilers. The concentrations of total carbon, sulfuric acid and metals of type 1 were 70%, 10% and 15%, respectively. On the other hand, the concentrations of total carbon, sulfuric acid and water of type 2 were 10%, 50% and 40%, respectively. In the case of glass melting furnace, there was no significant difference between type 1 and type 2 and sulfuric acidion was a major component.
Air dilution method and water-cooled method for dust measurement by type 2 were tested and they were compared with type 1 +type 2 method. As the result, there were no obvious differences between them.
From these results, dust concentration measured by the present JIS method (type 1) is dependent on flue gas temperature, so that it is necessary to use the dust sampling part scuh as type 1 combined with type 2.

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Two collection methods for ammonia in the atmosphere were investigated, which were the filter impregnatedwith phosphoric acid etc. and the diffusion denuder coated with oxalic acid etc. As the result of collection tests in the field sampling, the filter impregnated with 5% phosphoric acid and 5% glycerin and the diffusion denuder coated with 1% oxalic acid in ethanol had a sufficient collection efficiency for ammonia in the atmosphere, while the impregnated filter and the diffusion denuder used with boric acid were not sufficient for ammonia collection. The collection efficiency of ammonia in the atmosphere were 96% for the filter impregnated with 5% phosphoric acid and 5% grycerin, and 92% for the diffusion denuder coatad with 1% oxalic acid in ethanol, respectively, at an air flow rate of 20l/min. Therefore, it was found that both of the impregnated filter and the diffusion denuder enable to collect sufficiently ammonia in the atmosphere at trace level.
The determination of ammonia was usually used by indophenol method. However, a variation of pH at coloring reaction occured due to phosphoric acid and oxalic acid in the sample solutions collected by the above method, so that it was difficult to determine ammonia in these sample solutions by usual indophenol method. In this study, the determination of ammonia was used by the modified indophenol method, which pH at coloring reaction was adjusted with a phosphate buffer added to sodium phenolnitroprusside solution. The modified method had a good precision. In case of an air sampling volume of 4.8 m³, more than O.13 μg/m³ of ammonia in the atmosphere could be detected by this method.

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The precise method for determination of small amounts of chlorobenzenes (monochlorobenzene and dichlorobenzenes) in air was studied and applied to the survey in wardrobes, indoors and in atmosphere. Air sampling was accomplished by adsorbing the pollutants in the collection tube packed with TENAX^® GC. The pollutants collected were desorbed from the tube by heating the tube at 220°C and injected with carrier gas into a gas chromatograph with a mass spectrometer (GC/MS). In the survey of an urban area (Kawasaki city) and rural area (Tanzawa Mountains), a concentration of para-dichlorobenzene (PDCB) which has been used as a moth repellent and deodorant was much higher than that of any other chlorobenzenes outdoors and indoors.
The concentrations of PDCB were as follows: 13 to 25 ppt in the rural area; 0.16 to 0.95 ppb in the urban area; 0. 044 to 2.0 ppm indoors; 0.2 to 88 ppm in the wardrobes. The concentrations of ortho-dichlorobenzene were 2 to 4 and 2 to 52 ppt in the rural and urban area, respectively. The concentrations of meta-dichlorobenzene were less than 1 ppt in both the rural and urban area. The concentrations of monochlorobenzene were 3 to 4 and 6 to 36ppt in the rural and urban area, respectively.

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Transport and transformation processes of air pollutants in long-range transport from coastal region to inland mountainous region were investigated using the cooperative field observation data. The observation was conducted during 26-30 July 1983 in the wide area from the coastal region around Tokyo Bay to the northeastern part of Nagano prefecture which is located in central Japan.
An air mass polluted around Tokyo Bay in the early morning and stayed there till noon, was transformed by photochemical reactions. Then it was transported inland by large-scale winds which blowing toward thermal low generated in the central mountainous region. At about 1600 JST, polluted air mass penetrated in the mountainous region, and after sunset it flowed down toward Japan Sea in the form of gravity current.
Path of the polluted air mass was in good correspondence with the air trajectory at the altitude of 100m calculated from pilot-balloon data. Its transport speed reached maximum at about 1500 JST, the average transport speed in daytime being 4.6 ms^-1.
The Lagrangian variation of NO, NO₂, O_x and hydrocarbon concentrations along the trajectory were in good correspondence with that observed by smog chamber experiment. This confirmed that the same photochemical reactions as observed in smog chamber were proceeded in the transported air mass, although there occured some deposition and feed of pollutants.

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Gaseous formaldehyde of known concentration was prepared by passing purified air through or over the solid paraformaldehyde which had been washed with water and dried at 60°C. The concentration could arbitrarily be changed in the range from ppb to ppm by changing the temperature, the flow rate of air, and the amount of paraformaldehyde and its packing geometry. The relative standard deviations of the concentrations at 1 l/min and 20 l/min of dilution air flow rates, determined gravimetrically every 10 days of generation, were 1.2% and 5.6% for 191 ppb and 9.8 ppb of formaldehyde, respectively.

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Personal exposure levels of NO₂ for office workers and housewives living in Tokyo and neighboring prefectures were measured in four seasons with NO₂ filter badge.
NO₂ concentrations in indoor and outdoor air in their offices and houses were also measured in the same periods.
Personal exposure levels in winter ranged from 13 to 132 ppb and its distribution pattern was remarkably different from the other seasons. Furthermore, the mean value of the levels in winter (37.7 ppb) showed two times or more than those of the seasons (15.2-17.9 ppb). This fact suggests that use of heating apparatus affects largely NO₂ indoor air pollution in winter seasons. Actually, NO₂ exposure levels of subjects used kerosene heater (43.6 ppb) and gas heater (33.4 ppb) were higher than those of subjects unused heating apparatus (18.0 ppb). Personal exposure levels of NO₂ for man and woman living in the same houses were correlated well each other.
The time spent indoors for office workers and housewives were both longer than 22 hours a day. Home staying time was about 60% of total indoor staying time for office workers and 90% or more for housewives.
Personal exposure levels were significantly related to indoor exposure levels at home in all seasons, and at office and kitchen in spring. Furthermore, personal exposure levels could be estimated from NO₂ concentrations and staying times in various living environment.

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