Quantitative analyses with ELISA adopting monoclonal antibody for PCB #118 and DRCALUX dioxin receptor/reporter gene assay were applied to 33 samples of PCB preparations and waste PCB stockpiles in order to grasp the concentration of major PCB congeners (e.g., #118) and evaluate TEQ of the complex mixtures of PCBs, respectively. Cleanup procedure was designed to separate PCBs from sample matrices by conducting DMSO partition and the following silica gel/sulfuric acid (44%) reflux treatment. With the cleanup, both the ELISA and DR-CALUX yielded a linear correlation with the corresponding chemical analysis results (PCB sum and WHO-TEQ, etc.) . Pole transformer oils (mineral oil-based) especially required the cleanup for the both assay evaluation due to the presence of strong matrix interferences. However, for the ELISA, only dilution of high PCB oil samples (transformer insulation oil, capacitor insulation oil, stabilizer oil and heat transfer medium containing 30-100% PCBs) with DMSO gave results in agreement with those obtained for the Kanechlor preparation counterparts.

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The data base system was developed to understand the pollution of dioxin. This data base is composed of 118 isomer concentrations, TEQ concentrations and congener concentrations with sampling date, sampling site, their position informations etc. We accumulated over 700 samples in this data base by past continuous survey. This data base can show isomer pattern graph, congener pattern graph, radar chart of selected isomers and TEQ composition graph. It also can make distribution map of TEQ concentrations and some isomers. Statistical analysis such as principal component analysis and multiple regression analysis is available to estimate dioxin sources. Source apportionment of dioxin is calculated by Chemical Mass Balance (CMB) method.
Based on the data base, it becomes clear that air is mainly polluted by emission from waste incinerator, while river water and soil are mainly polluted by impurities in herbicide such as pentachlorophenol (PCP) and chloronitrophen (CNP) . Source contribution of dioxin was predicted by multiple regression analysis and CMB method. These results indicate that waste incinerator accounts for over 60% of air samples, on the other hand, herbicide (PCP, CNP) accounts for over 60% of river water and soil samples.

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The analytical procedure for trace level organotin compounds in seawater by TDS-GC-MS method using the stir bar sorptive extraction method was developed. Using this technique, it was possible to shorten the pretreatment time drastically (about 3 hours), and to reduce sample volume to 100ml by the simplification of the pretreatment. Background Equivalent Concentration (BEC) of this method are 0.19 for tributyltin (TBT), and 0.14 pg ml^-1 for triphenyltin (TPT) . These blank levels showed the sufficient sensitivity of this method in order to analyze trace organotin compounds in open sea water. In the result, it was possible to analyze under 0.1 pg ml^-1 concentration range of TBT and TPT using this method. By using this technique, the improvement of simplification of the pretreatment and lower detection became possible.

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A generation apparatus of volatile boron compounds was constructed, and the produced boron was introduced into a plant exposure chamber in order to examine plant damage caused by the exposure.
The apparatus produced volatile boron at concentrations of 1.3mg/m³-2.7mg/m³ for several hours at temperature of 40-100°C.
After the exposure experiment, tips and peripheral regions of Geranium leaves were damaged similarly to the damaged plants observed at an event in Toyama prefecture in 2001. The concentration of boron in the leaves ranged between 160 to 5, 000μg/g, increasing nearly proportionally to the square of exposure days.
Boron concentrations in tips /peripherals of exposed leaves were found to be 1.2-3.6 times higher than those in central parts of exposed leaves, and 2.2-45 time higher than those in tips/peripherals of unexposed leaves. Lowest adverse effect levels as boron concentrations in damaged leaves were not clarified.
From the above results, the mechanism of plant damage observed in Toyama prefecture was estimated to be produced by volatile boron compounds which were adsorbed through stomata and accumulated in tips/peripheral regions of leaves.

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This research was carried out to analyze polychlorinated dibenzothiophenes (PCDTs) in soil and fly ash samples collected in Japan and to estimate dioxin-like endocrine disrupting potency and photodegradability of PCDTs. PCDTs were detected in both fly ash and soil samples, though the concentrations were lower than that of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurane (PCDFs) . An assay using an Ah-immnoassay kit for the 5 isomers with chlorine atoms substituted at 2, 3, 7, 8-positions demonstrated the Ah receptor binding activities of the isomers except for OCDT, indicating that PCDTs have potency to cause dioxin-like endocrine disruption. The degradation of PCDTs by UV irradiation proceeded in connection with dechlorination. The photodegradation rates of 2, 3, 7, 8-TeCDT and OCDT were lower than the corresponding isomers of PCDFs, i.e. 2, 3, 7, 8-TeCDF and OCDF, indicating that PCDTs are more stable against photodegradation.

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The concentrations of surfactant-derived impure and degradation compounds in water samples from the TE river differ among water sampling station. The concentration ranged from about 0.01 to about 0.20μg/l for alkylbenzene, from under quantification limit to about 0.010μg/l for 4-t-butylphenol, from about 0.005μg/l to about 0.050μg/l for 4-t-octylphenol, from under quantification limit to about 0.50μg/l for nonylphenol, from under quantification limit to about 0.10μg/l for nonylphenol monoethoxylate, from under quantification limit to about 0.02μg/l for 4-t-butylphenoxy acetic acid, and from about 0.02μg/l to about 0.07μg/l for 4-t-octylphenoxy acetic acid; chlorides and n-type alkylphenols were not detected.
In the TE river water, the anion surfactant concentration was estimated to be higher about 2, 000 times than alkylbenzene concentration, and the nonionic surfactant concentration to be higher about 200 times than the total concentration of nonylphenol and 4-t-octylphenol.
No impure and degradation compounds derived from surfactants were detected in the water supplies. This is because these compounds react with chlorine, forming by-products.

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We have studied a solvent extraction method for determination of five nitrogen-containing cyclic compounds (NCCCs), pyridine, quinoline, indole, acridine, and carbazole, in distilled water, tap water and river water by high performance liquid chromatography (HPLC) with ultraviolet detector (UV) . As a result, good linearity of the calibration curve was obtained in the concentration range from 0.05 mg·l^-1 to 2 mg·^-1. The recoveries for five NCCCs from river water at a concentration of 1μg·l^-1 was 66.6-84.6%, and coefficient of variation was 6.9-8.7% by using solvent extraction method. This measurement method could be successfully applied to the determination of five NCCCs in distilled water, tap water and river water.

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A gas chromatography/mass spectrometry (GC/MS) method by an adsorption/liquid extraction has been developed for the determination of organic pollutants in indoor air. Round robin tests using this method for eight organic pollutants such as toluene, ethylbenzene, o-and p-xylene, styrene, p-dichlorobenzene, trichloroethylene and tetrachloroethylene were conducted by 15 laboratories.
Three kinds of test samples were analyzed by each laboratory: a) an adsorbent of activated charcoal (sample A) on which gaseous sample of the pollutants was collected, b) an adsorbent of activated charcoal (sample B) to which methanol solution of the pollutants was directly added, c) carbon disulfide solution (sample C) of the pollutants. The pollutants were extracted from the adsorbents by carbon disulfide and then determined by gas chromatography/mass spectrometry (GC/MS) after addition of toluene-d₈ as an internal standard.
The observed values of the pollutants except for those of styrene and p-dichlorobenzene after rejection tests were coincident with the calculated values. The recoveries of styrene and p-dichlorobenzene from the adsorbent of charcoal, that is, the ratios of the observed values to the calculated ones were 0.34-0.57 and 0.51-0.66, respectively. The intra-laboratory relative standard deviations (RSD) of the ratios for all samples were 0.74-12%. The interlaboratory RSDs of the ratios for sample A were 49% for styrene, 33% for p-dichlorobenzene, and 8.512% for the others. The RDSs for sample B were 33% for styrene, 22% for p-dichlorobenzene, and 14-19% for the others. The RDSs of sample C were in the range of 2.8-8.0% for all pollutants.
These results indicated that the six pollutants in indoor air except for styrene and p-dichlorobenzene could be determined precisely by using this method. It should be necessary to develop the alternative calibration method and/or improve the recovery of those two pollutants from the adsorbent of charcoal for precise and simultaneous determination of all the pollutants.

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