Uptake of atmospheric gaseous pollutants in respiratory conducting airways was studied on the basis of the mass transfer theory. The overall mass transfer coefficient K_a was determined as a function of four parameters, i. e., mass transfer coefficients in gas phase and liquid phase, k_g and k₁, solubility of pollutant q and ratio of pollutant transferred to circulatory system to that retained in tissue p. The mass transfer coefficients, k_g and k₁, were investigated in the previous report which presented the analysis of the literature experimental data. The rate of absorption of pollutant in respiratory conducting airways was obtained in terms of the overall mass transfer coefficient K_a. Thus the absorbed fraction of pollutant from inspired air was derived according to Weibel's model of regular dichotomy for human respiratory airways. These analysis showed that the absorption of SO₂, H₂S, NH₃, Cl₂, (CH₃)₂CO and (C₂H₅)₂O amounted to nearly 100 % through conducting airways. The absorptions of benzene, toluene and chloroform range between 20 and 70 %.

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The previous reports presented the application of the double film model to absorption of gaseous pollutants across mucus-tissue boundary in respiratory airways. The model was applied to those gaseous pollutants which dissolve into water at chemical equilibrium at gas-liquid interface. The resent paper aims at an extension of the double film model to uptake of nitrogen oxides. Dissolution of NO₂ into water does not proceed at chemical equilibrium at gas-liquid interface, since the rate of dissolution is slow. The overall mass transfer rate of NO₂ depends not only upon mass transfer process but upon the chemical process, i. e. dissolution. Thus the overall mass transfer coefficient K_a involves the mass transfer coefficients of gas and liquid phase k_g and k_l, and the rate of dissolution k₂. Uptake of nitrogen oxides in human respiratory conducting airways was given in terms of the overall mass transfer coefficient thus determined. The results of calculation are given as below. NO in inspired air is absorbed by 1.2 % in physical dissolution through respiratory conducting airways if NO₂ is not contained. NO₂ is absorbed by 13 %. If both NO and NO₂ are present in inspired air, NO is absorbed not only in physical dissolution but also in equimolar dissolution along with NO₂ (NO+NO₂+H₂O→2NO^-₂+2H⁺). If inspired air contains both NO and NO₂ in the proportion of 10 to 1, the absorption of NO₂ and NO are 13 % and 2.5 % respectively.

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Total mercury concentrations in the rain water collected in Kobe for one year were measured by using reduction-aeration, gold amalgamation and AAS.
The concentrations averaged 26.6 ng/l for 300 determinations (range 1-136 ng/l) and the order of their magnitude was winter, spring-autumn, summer. And they were able to be treated as a lognormal distribution.
The decreasing mode of mercury concentrations with increasing of rainfall amounts was compared with those of sulphate and nitrate concentrations.
As a result of regression analysis between mercury concentration and each component, a significant correlation between mercury concentration and H⁺ concentration was found.
Authors proposed on the basis of the experiments that there were following three pathways for the uptake of mercury species from air to rainwater;(1) washout of particles adsorbed and dissolved mercury, (2) dissolution of HgCl₂ and (3) dissolution of Hg° and successive oxidation to Hg (II).

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Human and rat (Sprague-Dawley, male; Body weight, 320+10 g) erythrocytes were nitrosylated anaerobically and the rheological alterations induced by exposure to air were examined. Further, acute exposure experiment on rats to 25-250 ppm NO was carried out by using an exposure chamber for single animal.
(1) The suspension viscosity of human erythrocytes (measured by a cone-plate viscometer) increased in 10-20% in low shear rates compared with the control after 4 hr exposure to air. The deformability of erythrocytes (measured by a high shear rheoscope) was not altered significantly, but the rouleaux formation of erythrocytes in autologous plasma (measured by a low shear rheoscope combined with TV-image analyzer) was suppressed. The phenomena were explained by the echinocytic transformation of nitrosylated erythrocytes after exposing to air. The biochemical analyses of erythrocyte membrane revealed (a) no changes of the composition of major fatty acids of phospholipids but (b) oxidative crosslinking of proteins by disulfide bridge formation (detected by 1% sodium dodecyl sulfate-4% polyacrylamide gel electrophoresis).
(2) The similar experiments for rat erythrocytes showed the remarkable and rapid oxidative crosslinking among membrane proteins (mainly, spectrin) and denatured globin. The crosslinking was restored completely by a reducing agent, mercaptoethanol.
(3) In in vitro experiment in rats to 25 250 ppm NO for 1 hr, 0.08-3% nitrosylhemoglobin and 0.6-20 % methemoglobin were formed dependent on exposed NO concentration. The viscosity of rat blood was not influenced by NO exposure within experimental error, but some echinocytes (with poor deformability) were detected. The oxidative crosslinking of membrane proteins as observed in in vitro experiments was not detected, perhaps due to the analytical limitation, some repairing mechanisms in erythrocytes, the selective removal of damaged erythrocytes in the reticuloendotherial system, and so forth.

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Seasonal variations of personal NO₂ exposures were measured for 10 housewives living in Suginami Ward, a residential area in central Tokyo. A year round survey were performed from. January to December 1982. Daily average of the exposures was measured by filter badge for continuous 7 days in every month.
Subjects could be devided into two groups from the seasonal pattern of the exposures. Subjects in the first group were exposed to high concentrations of NO₂ in wintertime, because they used unvented space heaters and/or did not use ventilators in kitchens frequently enough. In the other group, seasonal variations were not significant and their exposure levels were almost equivalent to the summer exposure levels of the first group. Subjects in the second group were found to be using vented space heaters or consume only little amount of fuel on unvented space heaters. Distribution pattern of year round exposures was nearer to logarithmic niormal distribution than to normal distribution. The ratio of the exposures to outdoor NO₂ concentrations of the first group depended on the minimum temperature of the day and switched from 1.5 to 1.0 at 10°C. Annual geometrical averages of the exposures could be estimated with the personal exposures in February and in July and the ratio of days of the minimum temperature being below 10°C in a year. Annual averages thus estimated agreed with the observed data.

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A liquid chromatographic method is presented for trace determination of 10 polynuclear aromatic hydrcarbons (PAHs), i. e., fluoranthene, pyrene, chrysene, perylene, benzo (k) fluoranthene, benzo (e) pyrene, benzo (a) pyrene, benzo (ghi) perylene, indeno (1, 2, 3-cd) pyrene, and coronene, in airborne particulates. Airborne particulates were collected on a quartz fiber filter for 24 hr by using conventional high volume air sampler. A part of the filter was cut out and placed in a centrifuge tube. Ethanol-benzene (3: 1, v/v) as an extracting medium was added to the tube. After removing bubbles attached to the filter, PAHs were extracted by ultrasonic agitation at 15-20°C for 15 min. Bubbles, which were still attached to the filter, were removed again and PAHs were completely extracted by ultrasonic agitation for another 10 min. The tube was centrifuged at 3, 000 rpm for 10 min. Supernatant of the extract was transferred to another centrifuge tube, 5 % sodium hydroxide aqueous solution was added and the tube was vigorously shaken for 1 min. After centrifugation at 3, 000 rpm for 10 min, upper layer (benzene layer) was transferred to a test tube, concentrated under a reduced pressure and dried under a nitrogen stream. A residue was dissolved in small amount of acetonitrile and analyzed by high performance liquid chromatography with spectroflurometric detection at the specific excitation and emission wavelengths for each PAH. The column consisted of a guard column (4.6 mm i.d.× 33 mm stainless steel column packed with Nucleosil 7C₁₈) and an analytical column (Analytical-PAH, 2.0 mm i.d.×250 mm). Mobile phase was water-acetonitrile (from 65 to 90 vol% acetonitrile, 2.5%/min gradient). Column temperature was 30°C. Recoveries of PAHs from the extract of airborne particulates were 99.2-107 % with 2.0-5.9 % relative standard deviation. The detection limits of PAHs (S/N=2) were 8200 pg. A good agreement was obtained between the analytical results for 10 airborne particulate samples by the proposed method and those by a conventional method including ultrasonic extraction, one-dimensional dual band thin-layer chromatography and spectrofluorometry.

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Relations between respiratory symptoms and their possible effecting factors of air pollution, smoking, home heating, age and sex, were investigated on 3, 302 inhabitants with the self-completion questionnaires of ATS-DLD. And, 153 persons who showed any respiratory symptoms in answers of the questionnaires were asked again with same questionnaires by direct interview to compare the two methods.
Results are as follows:
1) Self-completion questionnaires
Prevalence rate of persistent cough and/or phlegm and rate of breathlessness were increased by aging. The persistent cough and/or phlegm in males was higher than in females. The rate of persistent cough and/or phlegm in smokers was hihger than that in non-smokers. The rate of persistent cough and/or phlegm and rate of wheezing and/or asthmatic attack increased with number of cigarettes per day. The investigated area was divided into 4 zones, power plant zone, surrounding zone of the plant, urban zone and suburbs. No significant differences of the prevalences were observed. Air pollution levels in these zones are less than the national air quality standards in all items, so it shows the pollution had no effects under the conditions of less than the standard. Relation was found between the rate of respiratory symptom and exhaust from kerosene heater of living room. The rates were 2.21% on chronic bronchitis syndrome (cough and phlegm, consecutively over 3 months/year, over 2 years) and 3.65% on asthmatic attack in group of over 40 years old.
2) Comparison of the self-completion to direct interview
In general, agreements between two methods reached over about 80%. Number of the people who replied with same answer to same question in two methods increased with intensity of the symptom. In smoking and living conditions, the answers were also satisfactorily agreed.

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Effects of polynuclear aromatic hydrocarbons on the mutagenic activity of nitro aromatic compounds were investigated by the pre-incubation method using Salmonella typhimurium strain TA98 without S-9 mix.
Pyrene gave an enhancing effect for the mutagenicity of trinitrochlorobenzene. On the other hand, pyrene or BaP gave inhibitory effects for the mutagenicity of tetramitrocarbazole. Formation of charge-transfer complex was suggested for one of reason of these effects.

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While high volume sampling of air borne particulates for consecutive days, a fire of a house happened at 20 m distance from the sampling site. The sampler was surrounded with fire smoke for about 30 min.
The concentration of total suspended particulates (TSP) was 0.10 mg/m³ (24 hr average) in the before or after (ordinary) days, and the benzene extracts (tar) were 7.0-7.9 %, while the concentration of TSP in the fire day was 0.16 mg/m³ and the tar was 10.6 %.
Supposed that the increase of TSP in the fire day was due to the fire smoke, the concentration of TSP in fire time was estimated at 2.4 mg/m³, about 24 fold higher than in ordinary day and the tar in TSP at 17.7 %, 2.4 fold higher than in ordinary day. These estimations suggested that components of TSP in the fire time was rather different from those in ordinary days.
Tar of the fire day, half of which originated from the fire smoke, was as mutagenic as those of ordinary days toward TA98 and TA 100 and showed linear dose dependency under 200μg/plate. The mutagenic activity was enhanced by S9 mix. At 400μg/plate, however, the increase of revertant colonies with the tar of the fire day was less than that with the tars of ordinary days in the presence of S9 mix or not. This effect did not seem to be due to toxicity of the tar.
Inducibility of SCE of these tars was compared at 2 doses, 40μg/ml and 80μg/ml. SCEs were induced dosedependently by all the tars and statistically significant differences were not found among their SCE frequencies.
Although mutagenic and SCE inducible activities per tar weight were similar in the fire day and ordinary days, those activities per air volume of the fire day were much higher, the former 30-90 fold and the latter 60 fold, than in ordinary days.

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