Employing a wind tunnel, the effect of wind velocity was examined on the simplified measuring methods of nitrogen dioxide (NO₂) concentration in the ambient atmosphere using a filter paper treated with triethanalamine. The methods used were triethanolaminetreated filter paper method, Amaya's simplified method, and TGS filter paper method.
Measured values of the simplified methods varied on a large scale against the wind velocity and were fitted as a power function of the wind velocity. Furthermore, it became evident that the valus also depended on the wind direction. The above mentioned simplified methods of atmospheric NO₂ monitoring were unsuitable because the wind velocity and direction were changing in the actual atmosphere.

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Metabolic fate of inhaled NO was studied by exposure to ¹⁵NO and intraperitoneal in jection of ¹⁵N-nitrite and ¹⁵N-nitrate using rats and mice.
1) After exposure to ¹⁵NO (145 ppm, 123 min) and intraperitoneal in jection of ¹⁵N-nitrite (2 mg as ¹⁵N/animal) and ¹⁵N-nitrate (2 mg as ¹⁵N/animal), the recoveries of ¹⁵N in rat urine of 48 hours period were estimated. These values were 55, 53 and 78% of ¹⁵N exposed or in jected respectively.
2) The ¹⁵N-nitrite-ion in the urine was converted into the 6-nitro-derivative of 3, 4-xylenol, and was identified, determined by GC-MS method. The ¹⁵N-urea in the urine was identified and determined by using urease. The composition of ¹⁵N in rat urine after exposure to ¹⁵NO was 75 and 24% in the form of NO₃^- and urea respectively. At the case of rat urine, after in jection of ¹⁵N-nitrite, the unknown ¹⁵N compound was found in the considerable content, although it was not found in the case of inhalation. The amount of urea-¹⁵N after in jection of ¹⁵N-nitrate was lower than these of ¹⁵N-nitrite in jection.
3) Distribution of ¹⁵N was estimated after intraperitoneal in jection of ¹⁵N-nitrite (0.62 mg as ¹⁵N/mouce) using mice, and 60.7, 7.8, 0.3 and 1.6% of ¹⁵N in jected were found in the urine, fecal, exhaled gas during 48 hours, and the whole body after 48 hours, respectively. The ¹⁵N of remaining 30% was not recovered.

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In four species of laboratory animals (rabbit, guinea pig, rat, and hamster) of limited ages, we compared the static volume-pressure (V/P) curve of lung, and the content and composition ofphospholipid (PL) in the fraction of white layer (a crude lung surfactant) obtained from the lung lavage fluid. The V/P curve was hardly obtained in the guinea pigs because of so high openning pressure of their lungs. The distensibility per unit weight of the lung was found to be different among the other three species. The content of PL and phosphatidyl choline (PC) in the fraction of white layer appeared to be lower in the rats than in the other species when normalized for the lung weight, although no meaningful difference in the composition of PL and the fatty acid composition of PC was noted among the species.
Effects of the exposure to 2.3 ppm O₃ for three hours were also compared. The effect on the V/P curve was more evident in the rats than in the rabbits and hamster, demonstrating the reduced distensibility and the increased air-trapping in the lungs at lower distending pressures. Differed changes in the content of PL and PC in the fraction of white layer were noted among the species.
Age difference is an additional factor to be considered, but we present these datato contribute to basic informations concerning the species difference of lung physiology and biochemistr which are required in inhalation experiment with atmospheric pollutants.

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Conversion of NO_x to NO₂^- on filters was investigated by using NaOH (NaCl) impregnated on filter, NaCl aerosol (H₂O vapor) generated by nebulizer and 6.22-600ppm (v/v) NO_x, to estimate the amount of particulate NO₂^- formation in the atmosphere.
By the reaction of NO₂ with NaOH, particulate NO₂^- concentration formed (and/or collected) on filters was increased with a increase in both NO₂^- and NaCl-concentration, and the NO₃^--N/NO₂^--N ratio was decreased with a increase in NaOH concentration, but the ratio less than 1 was scarcely obtained.
By the reaction of NO₂-NO-H₂O-air mixture with NaCl, the amount of NO₂^--formation depended mainly on H2O and NaCl, as well as NO_x and other experimental conditions, but thatof NO₃^- was almost constant, and the ratio of NO₂^--N/NO₃^--N formed under these conditions was about 1%.
Additional production of NO₂^- resulting from absorption of gaseous NO₂ on particulate NO₂^- was not observed.

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Rats were exposed to 0.1 and 0.5 ppm SO₂ continously for 4 weeks. The histopathological examinations revealed the inflammatory changes such as submucosal histiocytic infiltration, submucosal lymphoid hyperplasia and thickning of alveolar wall on respiratory tract in both group. These findings were not evident in the control group. The histopathological findings of rats exposed to 0.5 ppm SO₂ showed higher severity than those exposed to 0.1 ppm SO₂. The histochemical findings of activities of acid phosphatase, alkaline phosphatase, NADH diaphorase in the tissue of trachea and lung revealedthe similar inflammatory changes as noted in histopathological examinations.
The loss of fur in vitamin B₁-deficient rats exposed to 0.5 ppm SO₂ was observed earlier than in those exposed to 0.1 ppm SO₂ or in those non-exposed rats. General emaciation of vitamin B₁-deficient rats seemed to be promoted by exposure to 0.5 ppm SO₂.

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On the rats exposed to 500ppm carbon monoxide for 1 week, the congestion of brain tissue and degeneration of Betz cells or Purkinje cells were found. These findings were not shown on the rats 1 month after the discontinuance of the exposure. The difference of the amount on the urinary excretion of coproporphyrin between exposed rats and control was not clear.
On the rats exposed to 100 ppm carbon monoxide for 22-45 days, the slight alterations such as congestion of brain tissue and degeneration of nerve cells were found. On the rats exposed to 30 ppm carbon monoxide for 22-45 days, there was shown no more than the slight swelling of brain tissue.

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It is necessary to find a simple technique for extracting mutagens in airborne particulates in the mutagenicity monitoring of air pollutants. At present, soxhlet extraction method has losen widely used for this purpose. This method, however, has several difficulties such as possibilityof artifact mutagen formation, poor ability to treating many samples at one time-consuming process involved. To overcome these difficulties, we studied a new technique, ultrasonic method, for the extraction of mutagens in airborne particulates.
At first, mutagenic activities of the ultrasonic extracts of airborne particulates were compared with those of the soxhlet extracts using benzene-ethanol (4: 1, v/v), methanol and acetonitrile as extracting solvent. Mutagenic activities of these extracts were measured by the pre-incubation method using Salmonella typhimurium TA 100 and TA 98 strains with and without S-9 mix. This test showed that mutagenic activities of benzene-ethanol and methanol extracts by the ultrasonic extraction were slightly higher or equivalent as compared with those by the soxhlet extraction. However, acetonitrile extract by soxhlet extraction showed higher mutagenic activity than the extract by the ultrasonic extraction. This discrepancy was remarkable in the mutagenicity test without S-9 mix. In due consideration of the previous results on mutagenicity of extracts of airborne particulates by the soxhlet extraction using many kinds of organic solvent as extracting agent [this journal, 18, 18-25, (1981)], it was judged that this discrepancy was due to artifact mutagen formation in the soxhlet extraction process using acetonitrile as a extracting agent.
In the second experiment, mutagenic activity was tested for 10 organic solvent-extracts of airborne particulates to find the most suitable extracting solvent in the ultrasonic extraction. Solvent used were acetone, acetonitrile, benzene, benzene-ethanol (4: 1, v/v), cyclohexane, 1, 2-dichloroethane, dichloromethane, ethanol, ethylacetate and methanol. Among these extracts, benzene-ethanol and methanol extracts showed the highest response.
The ultrasonic method allows to extract mutagens in many airborne samples at one time for about 15 min. Artifact mutagens was not produced when benzene-ethanol, methanol were used as an extracting solvent. Furthermore, benzene-ethanol ultrasonic extraction has been used in a chemical analysis of organic matter such as polynuclear aromatic hydrocarbons in airborne particulates. Considering these facts, it is concluded that the ultrasonic extraction method using benzene-ethanol is the most suitable technique for the biological and chemical monitoring of mutagens in airborne particulates.

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In order to facilitate the determination for extremely small amount of amine content in a lot of samples from the ambient air eliminating the preliminary concentrating procedure, the analysis method for monomethylamine (MMA), dimethylamine (DMA) and trimethylamine (TMA) consisting of the headspace method and the sampling method which amine component is collected on the filtering paper impregnated with sulfuric acid has been examined.
In this study, both gas chromatographic separation of amines and analytical sensitivity are improved.
Detection limit of MMA, DMA and TMA in 25l air sample are 5 ppb (v/v), 1 ppb (v/v) and 0.4 ppb (v/v), respectively.
Each coefficient of variation for head space analysis of MMA, DMA and TMA are 25.9%, 18.7% and 9.3%.

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An attempt was made to determine the heavy metal concentration of the epiphytic mosses on three barks in contaminated areas. Moss samples were collected in three contaminated areas (Omuta, Kanda and Tagawa) and three control areas (Kurume, Dazaifu and Maebaru). The great majority of the samples were the specimens of Entodon Challengeri (Par.) Card. The moss samples collected were ashed and examined for heavy metal contains by atomic absorption spectrometry.
The levels of certain heavy metals determined in the moss samples were characteristic of contaminated areas: Cd was higher in Omuta, Kanda and Tagawa areas than in the control areas, Zn in Omuta and Kanda areas than in the control areas, Pb in Omuta A (the region within 10 km of the zinc smelters), Kanda and Tagawa than in the control areas, and Cu and Fe in Kanda area than in the control areas. Two zinc smelters have conducted operations on large scales in Omuta area, and several factories have produced a large amount of cement in Kanda and Tagawa areas. The studies in Omuta area showed that Cd, Zn and Pb concentrations in the moss samples decreased with increasing distance from the zinc smelters.
From the above findings, it may be said that the determination of the heavy metal contents of the epiphytic mosses provides convincing data to the assessment of heavy metal contamination in terrestrial environments.

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