The supply of Chlorofluorocarbons (CFCs) is regulated because of its destructive reactivity to the stratospheric ozone layer. When using substitutes for CFCs, however, there are many obstacles at cost and in ability. In this situation, the best way to release no CFC is to catch the gas at source, then to recycle or decompose it.
In the study, the catalytic ability of the zeolitic pores of NaX zeolite for CFC-11 and CFC-12 was investigated. To examine in detail on catalysis mechanism of CFCs in the zeolitic pores, crystal structures of the zeolite pores before and after decomposition of CFCs molecules were analysed by using powder Xray diffractometry and IR spectroscopy. The bonds of Si-O and Al-O in zeolite structures were severed by the hydrochloric and hydrofluoric acid, which had been produced from CFCs and zeolitic water. It caused the deterioration of zeolite catalists.

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In order to clarify the effect of ozone on vitamin C, the changes of ascorbic acid and dehydroascorbic acid in lung tissue of mouse exposed to 0.2 to 4.1 ppm ozone for 4 to 16 hours were studied. The results were as follows:
1. Ascorbic acid levels in whole lung were decreased significantly by the exposure to more than 0.5 ppm for 4 hours or more than 0.2 ppm for 8 hours. Dehydroascorbic acid levels were not changed. Within 8 hours exposure, the decrease in ascorbic acid levels was proportional to the degree of exposure (concentration × time). The threshold of the degree of exposure to elicit decrease of ascorbic acid levels was calculated to be 0.6 ppm·Ehour.
2. After the cessation of exposure the decreased ascorbic acid levels turned to increase to higher than control level, then decreased to control level.
3. About 5% of ascorbic acid in whole lung was obtained by the bronchoalveolar wash. That ascorbic acid levels in airway were greatly decreased than the ascorbic acid levels in lung tissue by ozone exposure.
4.α-tocopherol levels in whole lung were not changed by the exposure to 4.1 ppm ozone for 4 hours.
5. Reduced glutathione levels in whole lung were decreased significantly by the exposure to 4.1 ppm ozone for 4 hours. The reduced glutathione levels in airway, which constituted about 1% of those in whole lung, were decreased significantly by the exposure to 2.0 ppm ozone for 4 hours.
6. These observations indicate that vitamin C in lung tissue is easily susceptible to ozone action than α-tocopherol and reduced glutathione, and this susceptibility is suggested to be mainly due to the presence of vitamin C in high proportion in the airway. The protective effect of vitamin C against ozone toxicity is suggested to be based on its high reactivity to ozone in lung.

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Two-year-old seedlings of Sugi (Japanese cedar: Cryptomeria japonica D. Don) and Hinoki (Japanese cypress: Chamaecyparis obtusa Sieb. et Zucc.) were grown for 4 months in 1/5 Hoagland's No.2 nutrient culture solution containing aluminum chloride in the concentration range of 0.5 to 20 mM within the pH range of 3.5 to 4.0.
Aluminium supplied at or below 1 mM of Al had no effect on the mortality of these species. However, the increase Al concentration higher than 2 mM increased the mortality. While they showed significant growth reduction at or higher Al concentration of 5 mM, there were no difference in growth response to Al between the two species in this experiment.
While Al contents in leaf and root significantly increased with increasing Al concentration in the solution, contents of Ca, Mg and P in leaf decreased. Roof P content in Sugi increased with the increase of Al concentration in the solution, while no such change was observed in Hinoki root. This result suggests that Al migth make phosphate immobile or inviolable form in Sugi root and this might lead to the reduced translocation of P into the leaf. In contrast, Al did not interfere with the uptake of phosphate in the root, however, it might interrupt phosphate transport into leaf from root system in Hinoki.
The Al concentration such as 5 mM in the root sphere induced growth reductions in Sugi and Hinoki, with no significant difference in the response between the two species. This concentration was much higher than those reported in the field crops, vegetables and/or herbs. Thus, if soil acidification will be induced by acidic deposition in future, these herbaceous plants will be influenced faster than the conifer trees. This also means that ground vegetaion change will be observed earlier than the conifer decline by the soil acidification stress.

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The single and combined effects of O₃, NO₂ and SO₂ on net photosynthetic rate (Pn) and leaf diffusive conductance (LDC) in 3-year-old Japanese cedar clones (Cryptomeria japonica D. Don, cv. Shibahara) were investigated. Moreover, the effects of air temperature (15, 25 and 35°C) and humidity (50 and 70% RH) on the response of Pn and LDC in the clones of two cultivars (Shibahara and Nakagen) to the mixture of 0.1 ppm O₃ and NO₂ were also investigated. At 25°C and 70% RH, the Pn and LDC in Shibahara clones did not reduce when they were exposed to 0.1 ppm O₃, NO₂ and SO₂ alone for three hours. However, the exposure to the mixture of the three gases resulted in the significant reductions in Pn and LDC. The reduction in Pn was caused not only by reduction in stomatal conductance but also by that in mesophyll conductance.
Although there were no effects of the mixture of 0.1 ppm O₃ and NO₂ on Pn, the effects on LDC depended on cultivars, air temperature and relative air humidity. By the exposure to the mixture of O₃ and NO₂, the LDC in Shibahara clones was significantly reduced at 15 and 35°C under the condition of 70% RH, while it was not reduced at 50% RH. On the other hand, no change in the LDC in Nakagen clones simultaneously exposed to O₃ and NO₂ was detected under all experimental conditions.

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In order to investigate the effect of dusts from opencut mines and cement factories on pH of the reservoir water, water soluble components in the falling dusts collected by the deposit gauge method were analyzed from February 1987 to February 1988 at 9 locations in Yukuhashi City, Fukuoka. The partial neutralization of acidic substances was shown to be caused by non-seasalt (nss-) alkaline calcium compounds in winter. The formation of magnesium hydroxide in the deposit gauges was confirmed as a characteristic phenomena in a cement industrial area. The nss-Cl^- deposition at location No.4 was affected by HCl and HClO gas from water purification plant. In summer, the Sea of Suou was the dominant source of sea salt particles deposited in Yukuhashi City. In winter months, however, sea salt transported far from the Sea of Genkai by the prevailing westerly wind was found to be the dominant sea salt components.

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An automated system has been developed for continuously monitoring atmospheric C₂-C₉ hydrocarbons in combination of a sample preconcentration technique and a capillary gas chromatography. The analytical column used is a 0.53 mm I.D. Alumina PLOT column connected to a 0.32 mm I. D. Methyl Silicon column as a resistance in series. A 100-200 ml of air sample is sampled on a trap packed with TENAX GC, activated alumina and activated carbon in series cooled at -10°C by using liquid carbon dioxide. The trapped components are foucused on the head of the analytical column at 40°C followed by determination by temperature-programmed gas chromatography. The analytical run time is 90 min for detecting 0.1 ppb of atmospheric hydrocarbon concentrations. The coefficients of variation are less than 2% of the determined values for consecutive 7 days.
This sytem is useful for on-site monitoring the prominent atmospheric hydrocarbons for long period even in the absence of an operator.

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