The method observing fluorescence-labeled bacteria under fluorescence microscope is an excellent cell analysis to obtain information biochemical and physiological activities, and morphological and genetic evidence in bacteria. Using this method we can analyze cells at the single cell level and also in the shorter period than using ordinary methods based on culture. Therefore, the application of this method can be expected in various fields, such as medical science, food industry, water quality control and so on. From this point of view, we overview recent evidence on total direct counting, vital staining, fluorescence in situ hybridization (FISH), and in situ PCR.

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"The Law on the Prohibition of Chemical Weapons and the Regulation of Specific Chemicals" was enacted in 1995 as the national implementation law for the "Chemical Weapons Convention". The Convention stipulates the general prohibition of the development, production, stockpiling and use of chemical weapons, and the destruction of chemical weapons that each State Party concerned with the establishment of this Convention owns. And under the Convention, the verification programme implemented by the international organization is established in order to secure these obligations. In addition, regulations with respect to chemicals, which are used in civil life but include materials for potential chemical weapons, are introduced. The primary object of this law is to ensure the adequate implementation of the Chemical Weapons Convention in Japan. Therefore, this law stipulates the prohibition of the production, possession, and transfer of chemical weapons as well as the regulation of the production and the use of specific chemicals required by the Convention.

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Since the end of 1960s, with an increase in the economic growth, a large amount of chemical products made from fossil fuel have been used. In addition to the development and the modification of the products for building materials containing many kinds of hazardous chemicals, the techniques for the airtight construction of houses have been remarkably developed. In the latter half of 1970s, among people living in U.S.A. and northern Europe a new syndrome with headache, dizziness, and eye irritation, etc., which was later called as a sick building syndrome (SBS), has emerged. This syndrome was found to be caused by concentrated multiple pollutants such as volatile organic compounds (VOCs) and allergens from fungi and ticks in high airtight rooms with lower ventilation. Recently, the number of patients suffering from biological allergens and VOCs tends to increase. But in Japan the standard values we have in the law on the sanitary management for buildings are limited to those for such three materials as carbon dioxide (CO₂), carbon monoxide (CO) and suspended particulate matter (SPM). Therefore, we describe in this report the necessity of the establishment of a new law on the indoor environmental standards for the prevention of our health against some kinds of indoor pollutants such as VOCs in cluding formaldehyde, nitrogen dioxide (NO₂), ozone (O₃) and asbestos produced not only in offices and working places but also in houses.

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The photodegradation method of polychlorobiphenyls (PCBs) in the TiO₂/Fe³⁺/H₂O₂/UV light system below 100°C was studied, focusing on the conduction band electrons reduction pathway in concert with Fe³⁺ and H₂O₂ at a higher concentration. It was found that PCBs were degraded effectively by the use of the photocatalyst, TiO₂ particle, suspended in a solution of ferric chloride, hydrogen peroxide and alcohols under irradiation at 253.7 nm. The degradation rate of PCBs at a concentration of ca. 333 μg/ml by the system was significantly improved when a newly developed TiO₂ rutile, ST-R1, and amphipathic solvents such as tert-butanol-metanol (9 : 1) were used. The degradation rates of KC 400, KC 500 and KC 600 were 94.6%, 82.7% and 61.4%, respectively, as measured by their decreasing amount in the solutions by GC-MS. Furthermore, the system was able to degrade p, p'-DDT by 87.1% and aldrin by 97.9%, respectively, and volatile organic compounds, 1, 1, 2, 2-tetrachloro-1, 2-difluoroethane (CFC-112), tetrachloroethylene (PCE) and trichloroethylene (TCE) by 70-92% at room temperature.

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To identify the metabolic pathway of selenomethionine (Se-Met), the behaviors of methylated metabolites in male Sprague-Dawley rats (6 weeks of age) treated orally with a single dosage (1 mg Se/kg body weight) of Se-Met, selenocystine (Se-Cys) or sodium selenite (Na₂SeO₃) were compared. The total Se contents in the kidney and in the liver from rats treated with these three Se compounds were both markedly higher than those in other organs. The highest accumulation of the total Se was recognized in these two organs of the group of rats given Se-Met. Although the cumulative total Se content excreted into the urine for 48 h after administration of Se-Met was highest, almost no difference could be detected among the urinary trimethylselenonium ion (TMSe) contents in these three administration groups. However, the total Se and TMSe contents excreted in the urine of rats in these groups for 12 h after administration of Se-Met were both twice those given Se-Cys or Na₂SeO₃. Furthermore, the amount of production of TMSe in the liver was rapidly elevated for 30 min after administration of Se-Met. In contrast, in the liver of rats given Se-Cys or Na₂SeO₃ TMSe was produced slowly. The findings that the TMSe formation in the liver of the group of rats given Se-Met occurs earlier than that in the group of rats given Se-Cys or Na₂SeO₃ suggested that Se-Met may be directly and enzymatically catabolized to produce methylselenol, which is easily methylated to TMSe.

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The cyanobacteria Microcystis which produces microcystin, as a hepatic toxin, has been found in the eutrophic water area including the source of water supply. The contamination of drinking water with these algae could be presumed. Therefore, the determination of microcystin in water by HPLC using a disk type solid phase extraction was studied. Microcystins-RR, -YR and -LR in the water were treated with Empore disks C-18 and SDB-XD (styrene divinyl benzene polymer). As a result, the SDB-XD disk using 10% H₂O-methanol as an eluent showed good recovery and reproducibility. This method can rapidly treat a water sample about ten times faster than the cartridge type solid phase extraction method. To clean the extract from the water sample, a method with a Sep-Pak silica cartridge which connects two pieces was tried using 0.2% TFA·10% H₂O-methanol as an eluent and this method also showed good recovery. The recovery of microcystin from spiked water was 102.3% for -RR, 103.2% for -YR and 91.2% for -LR. In the analysis of water samples collected from the water area yielding "water bloom", microcystin -RR 0-0.05 μg/l, -YR 0-0.02 μg/l and -LR 0-0.05 μg/l were detected in the water and in the samples collected from the algae cell, microcystin-RR 0.15-3.67 μg/l, -YR 0-1.21 μg/l and -LR 0.07-2.03 μg/l were detected. The release rate of microcystin from the algae to water was about 1%.

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The recently abused substances called "legal drugs", such as Natural Ecstacy, Herbal Ecstacy and RUSH, were analyzed to confirm that they contain no controlled drugs using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Seventeen samples were examined for narcotics, stimulants or other controlled substances. While none of them were detected, ephedrine and pseudoephedrine were found in five samples. Their concentrations were determined by high-performance liquid chromatography (LC) to be below ten per cent, within the limit regulated by the stimulants control law. Caffeine was also detected in seven samples. Therefore, the exciting effect of the "legal drugs" was considered to be caused by ephedrine, pseudoephedrine and caffeine.

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