Measurements of ozone concentrations were made at urban and nonurban stations in Kanto district during August to September 1982. The contribution of background ozone on the ground-level air quality in the metro politan area was discussed on the basis of the data obtained. Typical mean ozone levels of 16-25 ppb were evaluated in the August to September period. Meteorological analysis suggested that intrusions of ozone from stratosphere to lower troposphere took place behind cyclonic disturbances. However, hypothesis that stratospheric ozone contribute large amount of high oxidant spisodes could not be supported from the analysis. In the urban summer atmosphere, diurnal variations of ozone concentration were not produced by the intrusion of stratospheric ozone but by the photochemical reaction near the ground.

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Pollutants emitted from an elevated offshore source often bring a higher level concentration pattern due to the strong mixing in the internal boundary layer over land. This phenomenon is well known as fumigation and has been analysed by the conventional fumigation model. In this paper, however, it is analysed by a puff model which is more widely applicable to unsteady conditions around the offshore airport, such as the interaction of sea and land breezes and moving sources.
A good many tracer experiments were carried out around the proposed site of New Kansai Offshore Airport. In those experiments, there was a case in which two kinds of tracers were emitted simultaneously from the elevated and lower sources and the concentration patterns were obtained. In a previous paper the diffusion process for the lower source was studied in detail and three dimensional diffusion parameters as well as a few meteorological ones were determined with optimization technique by matching the calculated isopleths to the observed ones.
These parameters are modified by the unknown coeffficients in the present analysis and applied to the diffusion process for the elevated source. These coefficients are determined by using the optimization technique again.
All obtained parameters are quite reasonable compared with the characteristics of the dispersion process in the internal boundary layer and observed meteorological conditions. Good agreement is also presented between calculated and observed concentration isopleths.

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An analytical method for the rapid determination of total mercury in the rain water by using reduction-aeration, gold amalgamation and AAS was described.
The inorganic mercury which had been resistant to reduction in the rain water was not reduced in the acid solution, and was necessary to be reduced in the alkalized solution. The organic matter in the rain water was supposed to have no interference with the determination of organic mercury by this method.
The percentage of recovery and the coefficient of variation were 96-98% and 2.0-7.0% respectively at the level of 0.24-4.0ngHg/50ml. And the limit of detection was about 1ng/l, when 50ml of the sample was treated. The coefficient of variation and limit of detection obtained by this method was nearly equal to those by UV irradiation method.
This method was applied to the total mercury analysis of the rain water samples collected in the constant volume (100ml) in Kobe area.

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An analytical method for the determination of organic mercury in the rain water was described.
Organic mercury was transfered quantitatively into dithizonehexane solution from the last cysteine extract. The dithizonate was decomposed by heating and elementary mercury was determined by gold amalgamation and AAS.
Inorganic mercury adsorbed on the suspended particles in the rain water sample mixed into the benzene and cysteine extracts, and was analyzed as organic mercury.
The percentage of recovery was 84-85% and the detection limit was about 0.20 ng/l, when 800 ml of the rain water was treated.
The organic mercury concentrations and the ratios to total mercury concentration in the rain water collected in Kobe area ranged 0.20-1.5 ng/l and 0.5-6.2% respectively.
The organic mercury concentration in the atmosphere was calculated from those values and the Henry constant of CH₃HgCL. The highest concentration was 0.025 ng/m³, which was 1-3 orders of magnitude smaller than the literature values.

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The purpose of this paper is to present a method to predict the regional distribution of air pollutant concentration from the data obtained at monitoring network stations and its application.
Analyses are made to find the areas of high concentrations of pollutants with the application of the present method of estimating NOx concentrations in the atmosphere of the Tokyo Metropolitan Area. Subsequently, the important factors for such occurrences were determined with the applicationof statistical factor analysis based on a combination vector of wind direction and concentrations.
The results of the analysis are summarized as follows.
(1) There are five areas of high concentrations. Two areas are the central downtown with numerous emission sources and the eastern area with small-and medium-sized factories. Otherthree areas are in the central and western areas with fewer emission sources.
(2) By applying the combination vector of wind direction and pollutant concentrations, the correlation matrix of air pollutant concentrations among minotoring stations concerned is calculated. Then alnayses are made by means of statistical factor analysis, which extracts five factors. As the relationship between the areas of high concentrations and advection of the pollutant can be explained well by the factors, it is concluded that the combination vector of the wind direction and concentrations carries validity.

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An automatic analyzer for ammonia based on the oxydation activity of a reaction product between ammonia and sodium hypochlorite was developed.
The analyzer consists mainly of two parts, a reaction vessel and detection circuit device: Ammonia existing in the air sample is trapped and reacted with sodium hypochlorite in the former, and then is determined by coulometric analysis of the resulted reaction product in the latter.
According to the analytical program settled at a given measurement condition, trapping of ammonia existing in the air sample, its reaction with sodium hypochlorite, transfer of the resulted reaction product to the detection circuit device, electrolysis of free iodine in the coulometric cell and recording of the electrolytic current are all done automatically in the sequence-automatic system.
The lower detection limit was 50 μg/m³ and the measurement range of ammonia was (50-1000)μg/m³ in case of using a 10 liter air sample, and the coefficient of variation of analysis was 1.82% in case of an absorbent solution containing 5 μg of ammonia.
It was further found by an indirect confirmation test that the reaction product between ammonia and sodium hypoclorite was a chloramine-like substance.

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We developed a sample preparation method for mutagenicity assay of soil, and surveyed mutagenicity of soils collected in Tokyo area. Benzo (a) pyrene (BaP) contents were also surveyed in the same samples.
Soils were collected at 51 road-sides and parks located in various places of Tokyo in spring 1982 (industrial area, 17; commercial area, 9; residential area, 25). Fine particles in the soils were obtained by passing them through a 60 mesh sieve. Tarry matter in the fine particles was extracted ultrasonically with benzene-ethanol (3: 1, v/v) and dried under a reduced pressure. The tarry matter was sterilized by ethanol and dried again under a reduced pressure. The residue was dissolved in a small amount of ethylether. The resulting solution was stirred well after addition of a known amount of dimethyl sulfoxide (DMSO) and then ethylether was evaporated completely at a low temperature under a reduced pressure. These processes were essential for the elimination of interfering factors in the mutagenicity assay. Mutagenicity of the DMSO solution thus obtained was measured by the pre-incubation method using Salmonella typhimurium TA 100 and TA98 stains with and without S-9 mix. BaP contents in the soil samples were measured by the method which consisted of ultrasonic extraction, one-dimentional dual band thinlayer chromatography and spectrofluorometry.
Many soil samples showed positive response for the mutagenicity assay: number of samples showed positive response in the 51 soil samples was 25 for TA100 strain with S-9 mix, 0 for TA100 strain without S-9 mix, 46 for TA98 strain with S-9 mix and 44 for TA98 strain without S-9 mix. Number of soil samples which showed positive response for at least one of these 4 tests system was 49 out of 51 samples tested. Mutagenic activity was not so differed in the sampling areas. BaP contents in the soil were ranged from 191 to 282 ng/g, soil and not so differed in the sampling areas. Furthermore, BaP contents (μg/g, tar) were correlated well with the mutagenic activity (rev./mg, tar), especially with the activity in the test with S-9 mix. These results suggest strongly that Tokyo's soil has been contaminated with mutagens which mainly come from incomplete combustion including auto-exhausts.

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Acute in vivo exposure of rat (Sprague-Dawley SPF, male; body weight, 320±10g) to 100 and 200 ppm NO was performed in a small exposure chamber, and the time course of nitrosylhemoglobin (Hb-NO) and methemoglobin (Met Hb) formation in blood was simulated by the computer.
(1) The exposure chamber (volume, 1400 ml) for single rat was constructed so as to minimize NO₂ formation by the reaction of NO with O₂. The rat was anesthetized under NO exposure in the chamber by ether.
(2) The content of Hb-NO and Met Hb in the blood approached to a steady state at 30 to 60 min after exposure to 100 and 200 ppm NO. The concentration of Met Hb was 7 to 15 times of those of Hb-NO. Both hemoglobins disappeared within a half time of 20 min by the successive exposure to fresh air.
(3) The computer simulation for Hb-NO and Met Hb formation under NO exposure was carried out on the simplified reaction model by varying the following velocity constants: the association of 0₂ with deoxyhemoglobin, the dissociation of 0₂ from oxyhemoglobin, the association of NO with deoxyhemoglobin, the conversion of Hb-NO to Met Hb, and the reduction of Met Hb. The processes with unknown mechanisms were included in some velocity constants. The time courses of Hb-NO and Met Hb was semiquantitatively discussed on the basis of the computed kinetic parameters.
(4) In conclusion, (i) Hb-NO content under a steady inhalation of NO is maintained at fairly low level (0.4% for 100 ppm NO), (ii) Met Hb content is also kept at low level (less than 10% for 100 ppm NO) due to the enzymatic reduction of Met Hb in red cells. However (iii) the activity of Met Hb reductase seems to be inhibited by exposure to higher concentrations of NO.

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As to analysis of anions in rain water, ion chromatography (IC) incorporated with fast-run separator column and fiber-suppressor column (non suppressor column using ion exchange membrance) was able to measured six anions (F^-, Cl^-, NO₂^-, SO₃^2-, NO₃^-, SO₄^2-) with the eluent (3.0mM NaHCO_3-3.0mM Na₂CO₃) at a flow rate of 1.65 ml/min, simultaneously, rapidly and stably. Moreover, concerning to the aspect of detection limits for analysis, IC was superior to conventional method such as colorimetric analysis.
However, analytical method of cations (Na⁺, K⁺, Ca²⁺, Mg²⁺, NH₄⁺) in rain water by conventional method such as atomic absorption analysis, flame analysis and colorimetric analysis was superior to IC, since IC was not simultaneously measured univalent and divalent cations and was not so good as the aspect of speed for analysis and detection limits for analysis compared to conventional method.
S0₃^2-in rain water was oxidized gradually by affects of temperature, intensity of light and dissolved Fe ion in rain water, while NO₂^- was relatively stable compared to S0₃^2-.

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