This review is extracted from April 1984 to June 1988. A major source of information was JICST: enviromental pollution. In addition journals in the areas of air pollution and annual reports of institutes for air pollution were surveyed.
This review is divided into three section: sampling methods, analytical methods of odorants and surveys of odor sources

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Hg vapour (Hg°) removal from exhaust gas of a municipal refuse incinerator was tested using a pulsecorona-induced plasma chemical process (PPCP). The exhaust gas was mixed with Hg° to make a test gasof 0.5 mg/Nm³ Hg° concentration. An extremely rapid rising pulse, with a 100 ns rise time, was applied o a concentric cylinder corona system (inside diameter: 100.0 mm, discharge electrode: 4 mm×4 mm wire, effective length: 370 mm). Active species such as 0, Cl, etc. which oxidize Hg°are supposed to be generated by an intense corona discharge. The oxidized Hg was removed at a gas wash bottle with distilled water. For example, at gas temperature of 300°C, corona power of 3W and gas residense time of 7.5 s with negative polarity, Hg°removal efficiency was almost 100%. The Hg°removal efficiency increased with increasing pulse voltage, while it decreased with increasing gas temperature in the range of 150°Cand 350°C.

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Experimental studies have been undertaken on NO and SO₂ oxidation by pulse-corona-induced plasma chemical process (PPCP) at a pulse voltage of a 100 ns rise time. The exhaust gas from a municipal refuse incinerator added with NO and SO₂ were led to a concentric cylinder corona system. As both waveform of pulse voltage and gas residence time were constant, the removal efficiency (η) can be expressed as follows:η= 1-exp (-kf) where f is a pulse frequency ranging from 50 to 250 Hz and k is a constant coefficient. Therefore, NO removal efficiency (ηN) and SO₂ one (ηs) increased with increasing frequency. The pulse corona power required to gain the same ηN was only 10-20% of direct current one.ηN increased with increasing CO concentration, while ηs decreased as well as Hg vopour removal efficiency. From chemical analysis, it was found that the decrease in NO concentration was mainly due to the oxidation of NO and that the NOx concentration remained almost constant. The reaction was influenced by the concentration of O₂, H₂O, CO, etc. in exhaust gas. This may imply that the active species such as O, OH, HO₂, etc. produced by intense corona discharge were concerned with these reactions.

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The diffusion wind tunnl is wellknown very useful to predict pollutant gas concentrations released from continuous sources in the complex terrain and the similarity law for atmospheric diffusion entails turbulent simulation of wind direction fluctuation, σ_A observed over the concentration averaging time in the wind tunnel.
The new concentration overlapping technique with use of the turntable in the wind tunnel working section is here developed and shown useful to simulate high wind direction fluctuation which is beyond the convetional turbulence generators or wind oscillators.

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Radish plants (Raphanus sativus L. cv. Comet) were grown at 20/13°C, 25/18°C and 30/23°C (day/night) for 18 days after sowing. The plants were exposed to ozone (O₃) at 0. 1 ppm (v/v) for 4 hrs a day for 7 days from the 11th to 17th day after sowing. The dry weight growth of the plants grown at 25/18°C and 30/23°C was significantly reduced by 20% by the exposure to O₃ for 7 days. However, the dry weight growth of the plants grown at 20/13°C was not affected by the exposure to O₃ for 7 days. The results of growth analysis suggested that O₃-induced inhibition of dry weight growth is mainly due to the reduction in net assimilation rate.
Effects of 0.1ppm O₃ on net photosynthetic rates were examined for the plants grown at different temperatures. Net photosynthetic rates were measured at respective daytime temperatures under 1, 800, μmol·m^-2.s^-1 (60 Klux). Net photosynthetic rates of the plants grown at 25/18°C and 30/23°C were reduced by theexposure to O₃ for 4 hrs by 10.8% and 13.5%, respectively. Net photosynthetic rate of the plants grown at 20/13°C was not reduced by the exposure to O₃. The inhibition rates of net photosynthesis during exposure to O₃ for 4 hrs and the inhibition rates per unit O₃ absorption of net photosynthesis were ranked as follows: 30/23°C≥25/18°C<20/13°C
It is concluded that the increase of O₃-induced reduction in dry weight growth at relatively high temperatures (25/18°Cand 30/23°C) is mainly due to the greater inhibition of net photosynthesis at high temperatures.

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Chemical Mass Balance (CMB) method is one of the most popular techniques to evaluate quantitatively the apportionment of release sources using the chemical data of particulates measured at the source and environment.
In this study, the reliability of CMB method was investigated according to data either inhereing errors in source and environmental profiles or involving fluctuation in source profile data. Monthly concentrations of chemical elements at 4 receptor sites were calculated using an atmospheric diffusion model for artificial source profile data, and the “real apportionments F*” of each source type were determined for all of 48 samples. The source apportionments F were determined using the data involving errors or fluctuations. The reliability of CMB method was evaluated by comparing F* with F. Measurement error was assumed to be random in the range of 0-30%, and fluctuation in source profile data was assumed to obey the lognormal distribution in the range of 1-3 of fluctuation factor.
Source type having poorly characteristic indicator element does not have obvious quantitative relation between concentration of indicator element and the source apportionment, and then reliability of apportionment of such a source is low. On the other hand, in the case of source having highly characteristic indicator element, the apportionment is inversely proportional to the concentration of indicator element.
Assuming the allowable limit of error in the estimation of each source apportionment to be 25% of the “real” value, the maximum error permitted is 15% in the measurement of source and environmental profile data, and the maximum permissible fluctuation factor is 1. 3 for the source profile.

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In order to select the best distributional models for size fractionated particles and sulfates concentrations, measurements were carried out with Andersen sampler for continuous 1-year period in Hiroshima City. Sampling time was about 10 days. Four distributional models were chosen for selection: Normal, Lognormal, Gamma and Inverse Gaussian. Estimation of the parameters for these models are obtained using the maximum log-likelihood method. Normal is best for fine particles (D_p ≤ 1. 1 μm), Inverse Gaussian for coarse particles (D_p≥ 2. 1 μm), fine sulfates and coarse sulfates, Gamma for suspended particulate matter (fine plus coarse particles), respectively.
The size distributions of 10, 50, 90 percentile values indicate bimodal patterns with the peak at 0.65μm and 3. 3μm or 4. 7μm for particles, monomodal patterns with the peak at 0. 65μm for sulfates, respectively. It is suggested that these results are attributed to differences of the formation mechanism between fine and coarse particles and most of sulfates are secondary constituents.

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A β-ray attenuation type dust monitor was developed for continuous measurement of mass concentration of stack dust. The dust monitor has the isokinetic sampling system using microcomputor, the abatement system for dust deposition inside of the sampling nozzle by in jection of heated sheath air, and the compensation system for gas adsorption. Comparison of mass of dust collected on the filter between β-ray attenuation type dust monitor using Pm-147 and microbalance showed a good agreement with little error. Dust deposition inside of the 90 degree bend of sampling nozzle was decreased from 15 to 5% by heating sheath air from 25 up to 110°C and also decreased from 10 to 2% by flow rate of increasing sheath air from 7 to 12l/min. The measurements by the, β-ray attenuation type dust monitor showed a good agreement with those by the manual gravimetric method by JIS Z 8808, especially in the low concentration range below about 100mg/m³N.

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