The efficiency of the degradation of phenol in the presence of copper ion by immobilized cell was evaluated on the basis of the dynamic behavior of permeation of phenol and copper ion into gel bead. As a result of measuring concentration distribution of phenol and copper ion in the gel bead, it was found that the region where cell growth was not inhibited existed in the center part of the gel bead due to the low concentration of copper ion, and the cells could degrade phenol relatively easily in that region. The immobilized cell degraded phenol almost completely under fairly high concentration of copper ion, i.e. 1-10 mg/l. The mathematical model was presented for representing cell growth and phenol degradation in the gel bead, and the calculated values were verified experimentally in a batch treatment. It was suggested that the immobilized cell could degrade phenol in the presence of copper ion not only in a batch treatment but also in a continuous treatment.

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The leachability of boron in waste samples can vary both with boron content of the sample and with pH of the leachant. Boron leached more from dust, cinder and some waste ceramic samples when the solution was acidic, however, the mechanism of the leaching was not clear.
In order to better predict boron emission from waste landfill site into leachate, boron in waste samples (incineration ash, slag, waste glass etc) were fractioned (exchangable, carbonatebound, Fe-Mn oxide-bound, organic matter-bound and residual) by sequential extraction method followed by ICP atomic emission spectrometry and/or neutron guided prompt gamma ray analysis for the determination of boron in each fraction.
Distribution of boron among the five fractions differed from one sample to another. Correlation analysis of the results indicated that boron content in the “exchangeable” fraction was a better predictor of the leachability than was the total boron content of the sample.
Thermal treatment (1300°C) of the waste samples altered the original distribution profile of boron in the samples: more boron was found in less leachable fraction. Thus the present results indicated that waste fusion is a preferable approach to lessen boron emission from waste into leachate after landfill.

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The contamination level of polychlorinated dibenzo-p-dioxins (PCDII), polychlorinated dibenzofurans (PCDF), coplanar polychlorinated biphenyls (Co-PCB) and total PCB (PCBs) in fish, plankton, water and sediment samples from the administrated area of Tokyo Metropolitan Government in Tokyo bay were analyzed, and the sources and the transport of these chemicals were investigated. The range of concentrations of PCDD/DF and Co-PCB, and PCBs in the fishes were 4.5-18 pg-TEQ/g-wet and <100-460 ng/g-wet, respectively. The contamination level was considerably higher than other parts of Japan. Co-PCB accounted for 70-92 % based on TEQ in fish and plankton, and these ratio of Co-PCB were especially high. The isomer pattern of Co-PCB in each sample is similar to that of technical PCB product. The relation between concentrations of PCBs and Co-PCB in fish was observed. The isomer and homologue patterns of PCDD/DF in the sediments suggested that the contamination derived from herbicides and technical PCBs as well as combustion. The distribution of PCDD/DF Co-PCB and PCBs indicated that the contamination of Tokyo bay is due to transport and sedimentation caused by river inflows.

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The diethyl ether extracts from aqueous 4-alkylphenol solutions after treatment with chlorine were mutagenic to the Ames Salmonella tester strains TA98 and TA100 in the absence of rat liver homogenate. Gas chromatography/mass spectrometry (GC/MS) showed the occurrence of chlorinated products in the extracts; chloro-4-alkylphenols, chloro-4-alkylquinones and chlorinated 4-alkylphenol dimers. The diethyl ether extracts were fractionated into several fractions by polyamide thin-layer chromatography (TLC) . The fractionated components were examined for mutagenicity by means of Ames assay, and were identified by GC/MS. TLC fractionation of the extracts revealed that two components present in the extracts are mutagenic. GC/MS analyses indicated the presence of 2, 6 -dichloro-4-hydroxy-4-alkylcyclohexa-2, 5-dien-1-ones as the major mutagen and chlorinated 4-alkylphenol dimers as minor mutagenic compounds in the chlorinated 4-alkylphenol solutions.

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An infrared absorption determination method of sub-microgram oils was developed. Oil samples were extracted by hexane, and a 100 μl aliquot of the hexane solution was injected into a quartz boat. After hexane was evaporated under oxygen stream, the residue was burnt under oxygen stream at 850±20°C for two minutes. The resulting carbon dioxide was measured by none- disperse infrared spectrometer. The minimum detectable amount of oil was 0.1μg. The relation standard deviations were 0.8-1.8%. The recovery of oils were 90.3%-99.7% at 10μg.

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The fluorescence characteristics of humic and other fluorescence substances in river and sea water samples in Hamamatsu city were studied by analysing three-dimensional fluorescence spectra. The fluorescence intensity (λex=345nm, λem=430nm) and the absorbance at 250nm showed good correlation each other. Effects of filtration on the spectra were studied by using filter papers and membrane filters of various pore sizes. The effects varied considerably among samples as well as fluorescent peaks, but showed general dependence on the pore size of filters. Effects of solid extraction were examined using eight different types of solid extraction cartridge. Solid extraction suppressed fluorescence intensity in general, regardless of types or soluble conditions of fluorescent substances, and particularly AC2 cartridge could remove all the fluorescent substances.

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