The protease activities of sediments were assayed at 22 sites in the Kamo Estuary Tideland. The contour map of the activities showed spots of high activity located in two habitat areas for Uca lactea and Sargassum fulvellum. Electrophoretic analysis showed that each site contained several proteases. The electrophoretic profile of proteases differed among sampling sediments, except those obtained from the habitat area of Zostera japonica, which showed high degrees of similarity in protease composition.
Statistical analysis indicated that the protease activity was correlated with the concentrations of organic carbon and nitrogen in the tideland sediments. Loading of sediments with serum albumin as a protein substrate induced marked enhancement of protease activities. The addition of soluble starch or oleic acid did not cause activation of proteases. The activation of proteases by protein loading is more effective under aerobic conditions than anaerobic conditions. Electrophoretic analysis clearly indicated the presence of specific protease bands induced by protein loading of the sediments. The active bands were more intense under aerobic conditions than an-aerobic conditions. These results suggest that protein loading stimulates the secretion of proteases by certain microorganisms.

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The concentration of perfluorinated compounds (PFCs) contained in waste samples and eluted from the waste samples were measured respectively using sensitive method. The PFCs contained in the samples were extracted with methanol, while the PFCs were eluted with water. Afterward, the PFCs were separated, concentrated with nitrogen-gas and analyzed by LC/MS/MS. The results were considered focusing on the proportion and the difference in elution ratio of each PFCs.
As a result, it was confirmed that the concentration of PFCs contained in the samples can be measured without pulverizing solid waste. The differences in the concentrations contained in various kinds of waste samples were found depending on the category of industry, and treatment process. The elution ratio for the contained amount was different based on compounds. The short carbon chain compounds (C5-C8) had high elution rate, while long compounds (C9-C14) were low.

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On the analysis of polychlorinated biphenyls (PCBs) in electrical insulation oils which contain polychlorinated naphthalenes(PCNs), there could be quantitative error from PCNs, because of their high sensitivity in gas chromatograph/electron capture detector (GC/ECD). Thus, we have developed the PCN trap method which can remove PCNs selectively by carbon fiber. Although PCNs could be removed by this method, non-ortho PCBs and a part of mono-ortho PCBs also could be removed. But, KC-Mix in insulation oils have a little of PCBs which could be removed by the PCN trap method, and their influence on total concentration is low. We showed that the PCN trap method had comparable performance to the conventional method. In addition, we performed experiment for JIS 1 ∼ JIS 7 oils and DOP which were spiked PCN and PCB standards mixture and PCN-containing insulating oils. The results indicated that the PCN trap method were more accurate than the conventional method.

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We have investigated a simultaneous collection method for sulfur oxide and gaseous boron compounds in the emission gas using a small inside stack sampler (type-1 stack sampler) with a quartz filter paper of 25 mm in diameter impregnated with 2 ∼ 10% sodium peroxide and 0.1 ∼ 1% Pt-Al₂O₃+5%K₂CO₃.
It was proved that the simultaneous measurement of sulfur oxide and gaseous boron compounds is possible under the following conditions with both filter papers: the flow rate is 0.5-2.0 L/min, the sulfur oxide is 0.2-2ppm, and the gaseous boron is 0.02-1.0 mg/m³.

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Dechlorination mechanisms of aromatic compounds such as chlorophenol and chloroaniline under various conditions (e.g. dissolved oxygen in solution, chemical property of adsorbents, different adsorbates) were examined in the process of adsorption onto activated carbons. The dechlorination reaction occurred at ambient temperature and pressure when chlorophenol and chloroaniline were adsorbed onto activated carbon. The introduction of nitrogen in the carbon frame could enhance the reduction ability of activated carbon, which promoted the dechlorination reaction. The advance of the reaction would be related to the oxygen activated through radical reaction on the surface of activated carbon. Therefore, the dissolved oxygen in solution was necessary for dechloriantion, and would be one of the important factors for the dechlorination reaction. The amount of dechlorination was greatly differed according to the adsorbates. The adsorption of 4-chlorophenol on activated carbon caused an increase of chloride ion concentration in solution, while few concentration was detected in the case of 3-chlorophenol adsorption. The effects of solution temperature, pH and particle size of activated carbon were also investigated to inspect dechlorination mechanisms of aromatic compounds.

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An analytical method of phthalate esters including dimethyl phthalate, diethyl phthalate, dipropyl phthalate, diisobutyl phthalate and dibutyl phthalate in cosmetics was investigated using head space gas chromatography mass spectrometry(HS-GC/MS). Equilibration in the head space using Tetrahydrothiophene 1,1-Dioxide (sulforan) as solvent under the temperature and duration of 130 °C and 30 minutes, respectively, gave the result of accurate analysis possible.
Using this method, the concentration of phthalate esters in cosmetics were determined, and the results showed that dibutyl phthalate concentration in an eyebrow pencil was around 2000 μg/g (0.2%).

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The concentrations of trace level organotin compounds (TBT and TPT) in 32 seawater samples were analyzed by TDS-GC-MS with the stir bar sorptive extraction method.
The concentration range of TBT was 0.02-0.83 ng/L and of TPT was 0.002 to 0.17 ng/L. The maximum concentration of TBT was 0.83 ng/L at port of Yokohama and for TPT was 0.17 ng/L at Ofunato bay.
The concentrations of both the organotin compounds at the basin sampling points were relatively higher than the points at open sea. And also, in all the sampling points the concentration of TPT is about one order lower than TBT.
However in the Sea of Japan, points of relatively higher concentration of TBT were found, such as Japan Basin(0.35 ng/L). From this analytical result it is suggested that the pollution of TBT at the Sea of Japan has progressed in a wide range.
In contrast it seems that the concentration of TPT in the open sea was almost constant with no high concentration points seen in the Sea of Japan.

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Gas chromatography/mass spectrometry (GC/MS) is generally used for analysis of bisphenols in field environments. However, there are the cases that the sensitivity is not enough to determine their concentration. In this work, a liquid-chromatographic determination based on intramolecular excimer-forming fluorescence derivatization with a pyrene reagent, 4-(1-pyrene)butyryl chloride was examined for the analysis of bisphenol A in river waters. This method is highly selective and sensitive fluorometric method for biogenic related compounds, polyamines, polyphenols and dicarboxylic acids though it has never been applied for analysis of bisphenols in field environments. With the method, we determined concentrations of bisphenol A in waters sampled form 6 rivers in Shizuoka Prefecture. As a result, the values determined were ranged from 0.0016-0.17μg/L. They agreed with those determined by conventional method with GC/MS.

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