It is important to investigate the relations between the level of air pollutant concentration, its exposure time and their associated adverse effects on plant, animal and man.
We define “dosage” Dk (T) , which is the new measure of the level of air pollution, as follows,
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where x (t) is the air pollutant concentration at time t, x_c is the threshold concentration, T is the exposure time and U [x] is the unit step function.
The expectation and the variance of dosage are theoretically derived, when the probability density function of air pollutant concentration is approximated by log-normal distribution. The expected value of dosage is equivalent to the product of the k' th moment about origin and the exposure time when threshold value is zero.
The expected dosage is also calculated when the repair mechanism is considered. It is assumed in this dosage analysis that the adverse effect on plant and animal is related to the accumulation of tacit impairment, which is proportional to the square of concentration on the plant injury test and to the cube of concentration on the animal test.

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Measurements on the total concentration and size distribution of submicron aerosols in the mixing layer were performed over the Izu Islands of Japan, during October to November 1981. The purpose of observations was to get informations about transport, transformation and removal processes of anthropogenic materials from land to ocean. Continuous records were obtained by using Eiectrical aerosol analyzer (EAA) and Light-scattering particle counter which, overlapping steps, covered a size range 0.003 to 10μm diameter.
Results of observations showed that there were differences in the fate and behavior of aerosols depending upon meteological conditions. In the case of quiet and settled weather condition such as anticyclone over the mainland of Japan, concentration of aerosols showed maximum value (10³cm^-3) near the coastal area of Sagami Bay and minimum value (10²cm^-3) near Hachijo Is. Their dilution facter associated with spatial dispersion was estimated the order of 10^-6 to 10^-5m^-1. In the case of westerly wind prevailing, concentration of aerosols was immediately increased and the wind analysis suggested that pollutants had been transported from Chukyo district. At the condition of stratocumulus precipitation with medium cloud base, concentration of aerosols was decreased and distribution curve was deformed from Junge's power law of average maritime component. The collection efficiency of submicron aerosols calculated from observational results was much higher than the value which recent theories predict. Some possible explanations of these discrepancies were also discussed.

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For the evaluation of density distribution patterns of trace metallic compounds in the atmosphere, the fractions of atmospheric aerosols obtained by the heavy-liquid separation method with a series of dichloromethanemethylene iodide mixtures were subjected to elemental analysis for Zn, Fe, Mn, Cu and so forth using inductively coupled plasma-atomic emission spectrometry. The aerosol samples involve urban dust collected from air-inlet filters of air conditioning system, suspended particulate matter collected on polystyrene filters using a concentional high-volume sampler, a Japanese standard low-volume sampler and an Andersen size-fractionating sampler, and dustfall collected in a dust jar.
Concentration profiles as a function of density appreciably differ one another among these samples. Metallic compounds with the density lower than 2.3g/cm³ predominate in suspended particulate matter. On the other band, metallic compounds in dustfall are mainly associated with aerosols of high density (>3.3g/cm³). The density distribution curves also have the maxima at the density of 2.7g/cm³ which corresponds to the density of wind-blown silica. Differences in the density distributions of metallic compounds are also evident among the aerosols collected separatively in the size ranges 0.06-0.43, 0.43-1.1, 1.1-3.3, 3.3-11 and 11-33μm effective aerodynamic diameter at unit density. Aerosols with lower density tend to be collected on the higher stage of the Andersen sampler. For example, the concentration of Fe aerosols collected on stage 1 (11-30μm fraction) goes through a maximum at the density of 2.5g/cm³ and another small maximum at the density of >3.3g/cm³, while low-density Fe aerosols with the density of 1.7g/cm³ are predominant in the 0.06-0.43μm fraction.

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Adsorption behavior of N-containing compounds on porous polymer beads was studied in terms of the breakthrough curve with a dynamic adsorption technique.
A sample gas stream for each compound in a constant concentration was prepared with a permeation tube by diluting with a dry air. The collection tube was a glass tube (i. d. 6mm) packed with about 0.6 g of adsorbents, such as TENAX-GC, Porapak T, Chromosorb T, Chromosorb 103 and alkalized Porasil A.
From S-shaped breakthrough curve, the breakthrough volumes (V_b) for the nitrogen compounds on the adsorbents were calculated by multiplying a sampling rate to the breakthrough time. The temperature dependence curve for all of compounds studied exhibits a linear relationship between log V_b and 1/T but a saturation for amines in a region of low temperatures.
The adsorbed amount in the collection tube measured with FID-GC after enrichment and thermal injection increased with sample volume but reached the constant value around the equilibrium point. The magnitude of the maximum amount adsorbed (maximum loading capacity) varied with a gas concentration.
Adsorption isotherms were constructed from the maximum loading capacity as a function of gas concentration for TMA, acetonitrile and acrylonitrile on TENAX-GC, Chromosorb 103 and alkalized Porasil A.
From the results obtained, alkalized Porasil A turned out to be suitable for the adsorbent for air sampling and to make a sampling of at least 20 l for amines and nitriles at ppb levels.

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Total hydrocarbon concentration in emitted gas from the gasoline filling Process were 18.7-64.6%(v/v) with the temperature range of 0°C-40°C, and the major components were C₄-C₅ hydrocarbon, which accounted for 87.8-81.4% in total hydrocarbon. The concentration of aliphatic and aromatic hydrocarbons were respectively 18.4-63.8% and 0.26-1.53% with the same range.
The amount of the emitted gas during filling increased with the rising of the gasoline temperature. When the gasoline was filled at 0°C, it was almost the same as filled gasoline amount (1), but at 40°C about 1.2 times. Hydrocarbon emission factor was in proportion to the gasoline temperature and the regression formula was Y=0.0492x+0.247.(Y: emission factor (g/l), X: gasoline temperature (°C)).

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Frequency distributions of air pollutant concentrations are analyzed generally by assuming that they are lognormally distributed. However, the concentrations are not always lognormally distributed. The distribution model with good fitness to the observed distributions should be applied to the establishment of the environmental quality standard for regulation.
Hybrid-lognormal distribution is proposed and is validated to be applicable to the distribution of occupational radiation exposure, which is similar to the distribution of air pollutant concentrations.
In this paper, the statistical characteristics of hybrid-lognormal distribution is discussed, and it is shown that hybrid-lognormal distribution can well describe the distributions whose distribution function is between lognormal and normal on a curve paper, and that hybrid-lognormal distribution is applicable to the analysis of frequency distribution of air pollutant concentrations.

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The toxicological effects of photochemical oxidant mixtures (O_x) and Ozone (O₃) on Jet: ICR female mice were compared. The animals were exposed to O_x (peak concentration: 0.8-1.4 ppm), O₃ simulated to O_xpattern and O₃ at 3 ppm in constant concentration for 3 hours. O_x was generated by UV-irradiation in the smog chamber containing diluted automobile exhaust gas, nitric oxide and propylene. Immediately after the exposure, rectal temperature, blood pH, erythrocyte acetylchotinesterase and 2, 3-diphosphoglycerate (2, 3-DPG), serum cholinesterase (ChE), GPT, total bilirubin, total cholesterol, urea nitrogen and alkaline-phosphatase (ALP, basic and Mg activated types) and erythrocyte osmotic fragility were measured.
O_x was more effective than O₃ with simulated pattern of O_x on the changes of 2, 3-DPG, Mg activated type ALP, ChE and erythrocyte osmotic fragility, but less effective on urea nitrogen and total cholesterol. The effects of O_x and 0₃ on body temperature were in opposition. These results indicated that the toxicological effects of O_x could not be explained by O₃ alone.
We reported previously that leucocyte count, leuco-index and erythrocyte count increased in the mice exposed to O_x in accordance with clinical findings of the seriously suffered patients during the smog episodes. In the present report, arise of body temperature and the increase of ChE activity in animals exposed to O_x were also similar with the findings in the episodes. However, the facts that all of the clinical findings were not the same with those in animals exposed to O_x generated in the smog chamber suggested the presence of the other hazardous substances in real photochemical smog.

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In order to study on the relationships between the putrefaction and the offensive odor of solid waste, the volatile compounds produced by putrefaction of foods have been investigated. A variety of foods including fish, potato, cabbage, rice and apple were kept separately in20-litterr polyethylene bottle at 23°C for 2 months under anaerobic condition. Some substances contained in the headspace gas were identified by gas chromatography-mass spectrometry and determined by gas chromatography at regular intervals. At the same time, the offinsive odor was characterized by sensory test. The following results were obtained.
The quantitative increase of volatile components was almost complete after 3 weeks. In all foods, various esters were detected after a week. The intensity of offensive odor estimated by sensory test increased in the order apple, rice, cabbage, potato and fish. It was proved that the volatile profiles for different varieties of foods were qualitatively similar, but individual component concentrations differed among varieties. The more, sulfur compounds were produced by putrefaction of foods, the more intenstive the offensive odor of foods became. But, alcohols do not play an important role with regard to offensive odor of solid waste.

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The within-individual variability of olfactory thresholds was analyzed, for the purpose of investigation of influence of panel on olfactory sensory test. Three standard odorants (iso valeric acid, skatole, methyl cyclopentenoron) were used for olfactory accuity test. 13 panel members (males 5, females 8) were repeated this test 30 times. The following results were obtained.
1) The ratio of C.V.(coefficient of variation) of within-individual variability to C.V. of between-individual variability was about 5: 3.
2) About change of olfactory sensitivity with time, there was a little decrease in the sensitivity at the first time and the last time of the day. The same statement was true for just before and after noon recess.
3) As a result of 30 repetitive tests, there was significant difference between the first time and the second time. It may be caused by unskilfulness.
4) From this investigation, the correct answer ratio that express olfactory threshold was about 62%.

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Aldehydes in exhaust gas from dryers or apparatuses of the Zimmermann processes in night soil treatment plants can be removed by the addition reaction with sodium sulfite. The selection of anti-oxidant for Na₂SO₃ solution and the condition for aldehyde absorption were investigated in this paper. The following results were obtained. Glycerol is the most effective anti-oxidant. The optimum condition for aldehyde absorption at room temperature is specified as follows: superficial gas velocity; 1.0-1.7m/s, liquid/gas ratio: 2l/m³ (or larger), pH of the absorptive solution: around 7, Na₂SO₃ concentration: 5×10-2mol/l for 250 ppm aldehyde content (1×10-1mol/l for actual gas). Under this condition, exhaust gas for the Zimmermann process could be removed almost completely.

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Having examined the measurement wavelength range free from interference by coexistent substances in exhaust gas, a 340 nm single beam absorptiometric analyzer for hypochlorite was made and installed in a deodorization plant for controlling hypochlorite concentration.
Long-term continuous control was proved to be feasible within a deviation of ±5% from a set hypochlorite concentration (lower than 1, 000 ppm) in the absorption solution (pH 11), under the following conditions; flow rate at the cell: 100ml/min, span adjustment: once two every weeks, zero calibration: automatically.

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