The growth-inhibitory and lethal effects of zinc ion and copper ion on a phenol-degrading microorganism, Acinetobacter calcoaceticus AH strain, was examined by measuring optical density of cells, total cell number, viable cell number and macromolecule contents per cell in a batch culture. The effects of heavy metal ion concentrations on the specific growth rate and the specific change rate of viable cell number were clarified, suggesting that the inhibitory effect of copper ion was stronger than that of zinc ion and the copper ion caused not only the growth-inhibition but also the death of cells. The immobilized cell culture using alginate calcium gel beads as a carrier of cells was more effective for degrading phenol in the presence of a higher concentration of heavy metal ion rather than the conventional liquid culture. The repeated batch culture using immobilized cells could degrade 100 mg/l phenol containing 30 mg/l of zinc ion for 10 batch cultures and therefore provided the attention toward the applications in the effective degradation of phenol in the presence of heavy metal ion.

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The problems caused by volatility of 4-8 chlorinated analogues on measuring PCDD/Fs in the atmosphere were examined. First, the sampling method for measuring PCDD/Fs in the atmosphere using high volume air sampler (HiVol) equipped with filter paper and polyurethane form (PUF) was inspected. ¹³C₁₂-1, 2, 3, 4-TCDD, which is more volatile but less toxic than other tetrachloro-through octachloro-PCDD/Fs, was used as a sampling spike and added on the filter paper to confirm the collection efficiency. As a result, most of the sampling spike passed through the filter paper and was collected by the first step of PUF. Non of the sampling spike was detected on the second and subsequent steps of PUF. The total collection ratio from filter paper and PUF was unexpectedly low (40-60%) and so we checked the cause of it. The sampling spike, we guessed, would have been volatilized anywhere, because the spiked filter paper had been left for ca. 2 hours by the time of starting the sampling. This was confirmed by testing the volatility of it on the filter paper. Next, the volatility of the sampling spike at the time of the concentration operation such as nitrogen blowing was tested . As a result, the sampling spike existing alone in the operation of nitrogen blowing volatilized easily. However, in the case of the sampling spike existing with less volatile PCDD/Fs, the volatility of it was suppressed.

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Photographic developing solution is a mixed solution containing some organic substances of developing agents and a large amount of sodium sulfite, i.e., an antioxidant of the organic substances. Therefore, the wastewater of developer displays a high COD value. The treatment of the contained organic substances such as metol (p-methylaminophenol sulfate) and hydroquinone (p-dihydroxy-benzene) are hardly oxidized or decomposed because of the large amount of sulfite ions which exist.
In this research, removal of the sulfite ions from waste developers with calcium ions was first examined to precipitate sulfite ions as calcium sulfite and reduce COD value. The optimum conditions for this reaction were examined. Oxidation of the organic substances with hydrogen peroxide was also examined to reduce the COD value in the solution after the separation.
The following results were obtained as experimental results. Most of the sulfite ions in the solution were instantaneously removed by the addition of calcium chloride as a precipitate of calcium sulfite hemihydrate. Addition molar ratio of calcium to sulfite ions was found to be 1.5 at pH 8 for the removal sulfite ions of about 100%. The crystalline and the size of the precipitate were desirable for separation of the precipitates from the solution. By using hydrogen peroxide, the oxidation and decomposition of metol and hydroquinone was performed, then COD value of 80-90% of the initial waste solution was decreased.

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A gas chromatography/mass spectrometric method was applied to determine 101 pesticides and 10 transformation products in environmental water by using a membrane extraction disk for solid-phase extraction. A filtered water sample of 500ml was passed through a membrane extraction disk SDB-XC. Pesticides extracted on the disk were eluted with 10ml of acetone, 10ml of ethyl acetate, and then 10ml of hexane. After the eluate was concentrated to 1ml, it was dried over anhydrous sodium sulfate. To the solution was added 100μg of PEG 200 and PEG 300 and 1μg of internal standards (1, 4-diiodobenzene and 9-bromoanthracene) for GC/MS determination. Overall recoveries were 70% to 108% except for 2, 6-dichlorobenzamide and thiometon from ground water and were 71% to 110% except for 2, 6-dichlorobenzamide from filtered river water.

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A low flow rate cascade impactor with 3 stage (larger than 10μm, 2.5-10μm and smaller than 2.5 μm) has been developed to analyze levels of indoor airborne particulates and particulate hazardous compounds simply. A quartz fiber filter and a polytetrafluoroethylene (PTFE) filter, used for collecting airborne particulates, were compared. ICP-MS was used for the determination of elements after samples were digested with nitric acid, perchloric acid and hydrofluoric acid. The results were as follows; (1) Elemental contents of PTFE filter and the variations were quite smaller than those of quartz fiber filters. (2) The amounts of airborne particulate collected by PTFE filter without grease were lower than those of quartz fiber filter. But a coat of apiezon grease on the PTFE filter gave an accurate collection. (3) When the PTFE filter was used, coefficients of variation of elemental concentrations were ranged from 5% to 10%. (4) Almost all target elements were detected in the houses when the PTFE filter was used. These results suggest that the present method using the PTFE filter coated with apiezon grease for collecting airborne particulates was useful for analyzing size distribution of indoor particulate elements.

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A treatment process of the decomposition of chlorinated hydrocarbons in aqueous solution by high intensity ultrasonic irradiation has been studied. In this work, the effects of bottom thickness and volume of pyrex-glass reaction vessel, temperature, ultrasound frequency, ultrasound intensity, ultrasound oscillator and reaction atmosphere on the decomposition were investigated. Under the obtained optimum operation condition, over 80% of 10ppm trichloroethylene, tetrachloroethylene and 1, 1, 1-trichloroethane are decomposed within 10min. The major products were chloride anion, carbon monoxide, carbon dioxide and hydrogen.

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An analytical method for the determination of heterocyclic amines with liquid chromatography/mass spectrometry (LC/MS) has been developed. Under reversed-phase liquid-chromatographic conditions, heterocyclic amines have been analyzed using electrospray ionization (ESI) methods. The effects of post-column modification of the liquid chromatographic mobile phase, the fragmentor voltage with ESI methods, the flow rate of the drying gas and the pressure of the nebulizer gas with ESI methods on the sensitivity for the detection of heterocyclic amines were examined. A membrane extraction disk was used as solid phase extraction (SPE) for the isolation and the trace enrichment of hererocyclic amines from river-water samples. The extracts were directly injected into LC/MS system. The limit of detection (LOD) of these heterocyclic amines ranged from 1 ppt to 30ppt. The overall recoveries of these compounds were from 86.0 to 93% {RSD (n=5) from 1.9 to 4.5%} for river water.

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The decomposition of dilute chlorinated hydrocarbons, such as carbon tetrachloride, chlorobenezes, chlorophenoles and chloroacetaldehydes, in aqueous solution by high intensity ultrasonic irradiation were investigated. Besides chloroacetaldehydes, more than 85% of their initial amounts are rapidly decomposed in less than 1 hour. The major products were chloride anion, carbon monoxide, carbon dioxide and hydrogen. This reaction rate was accelerated under argon atmosphere. The sonolytical reactivity of these chlorinated hydrocarbons are influenced by their solubility in water and their volatility from water.

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The previous paper demonstrated that emission from a municipal waste incineration (MWI) plant was probably a main potential PCDD/DF source in midstream of the Tama River. Thus, fish samples caught from the midstream of this river, one from a heavily polluted site and the other from comparatively a low polluted site by PCDD/DF, were analyzed for their PCDD/DF levels and patterns, to compare with those found for the surface sediments. Fish sample taken up from the heavily polluted site near the MWI facility showed high I-TEQ value (14.0pg/g) of PCDD/DF as fresh weight (f.w.), although the PCDD/DF congener pattern was somewhat different as compared with that found for the sediment sample. HRGC/HRMS determinations for PCDD/DF in other fish sample caught from the low polluted site, which is at distance of 1 km from the MWI facility and there is a small dam between both sampling points, showed also high I-TEQ value of 7.26pg/g f.w. This value was not only about 23 times higher than that (0.3pg/g) found for the sediment collected from the same point, but also a extreme difference in the PCDD/DF patterns was observed for both fish and sediment samples.

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Organotin species in seawater, collected by using a ferry between Osaka and Beppu, were determined by gas chromatography combined with inductively coupled plasma mass spectrometry after the ethylation with sodium tetraethylborate. Distributions of 9 organotin species below 1 ng Sn/l in the Seto Inland Sea were clarified for the first time. The concentrations of tributyltin (TBT) and triphenyltin (TPhT) were in the range of 0.21-1.02 ng Sn/l and 0.021.0.096 ng Sn/l, respectively. Three unknown species among them were identified as mono-, di-, and tri-octyltin species, which were used as plastic stabilizers. Butyltin and phenyltin species except for TPhT were found to occur as dissolved form, but di- and tri-octyltin species were found to occur as particular form. Principal component analysis revealed the origin of pollution at each sampling station, i.e., whether it come from antifouling paints or from plastic stabilizers.

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This study was aimed at developing a biotechnological treatment to biodegrade dioxins and chlorophenols, and to remove NH₃-N simultaneously in landfill leachate using immobilized microorganisms.
Pseudomonas aeruginosa degrading dioxins and anaerobic-aerobic sludges habituated by landfill leachate from a treatment plant were immobilized by polyacrylamide.
Test result showed that biodegradability of dibenzofuran (DBF) and chlorophenols was higher under coexistence of Pseudomonas aeruginosa and anaerobic-aerobic sludges than that when only Pseudomonas aeruginosa was present. In order to establish condition for both biodegradation of DBF and 2, 4, 6-tetrachlorophenol (2, 4, 6-TCP) which has strong toxicity among chlorophenols, and removal of NH₃-N simultaneously, we studied aerobic-anaerobic treatment and anaerobic-aerobic circulating treatment. In a continuous cultivation system, DBF and 2, 4, 6-TCP were degraded to the level of detection limits of GC-FID after a month.

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A passive sampler of diffusion type is one of useful apparatus for the monitoring of gaseous substances in the open field where electric supply is limited. An improved passive sampler of pencil type for gaseous mercury was developed and applied to a preliminary survey of atmospheric gaseous mercury on landfill sites. The amount of collected mercury by the sampler was revealed to vary in proportion to the diameter of diffuser opening, and in inversely proportion to the length of diffuser. The efficiency of mercury absorption was approximately constant regardless of atmospheric concentration range (0.01-1 ng/day) . The atmospheric gaseous mercury concentration on landfill sites could be estimated to be about 2-2000 ng/m³ by the proposed passive sampler, which was in agreement with the data obtained by an active sampler.

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We determined the concentrations of 34 halogenated disinfection by-products in raw and tap water in an area by our new multi-component systematic analytical method.
The total concentration of all halogenated disinfection by-products was under 15 ng/ml in all raw water samples in the investigated area but under 5 ng/ml in many of them. According to the classes of halogenated by-products, the concentration of haloacetic acids was extremely high, and halogenated by-products showing the second highest concentration (haloacetones, haloacetaldehydes, or trihalomethanes) differed according to the characteristics of the raw water. Among haloacetic acids, the concentrations of dichloroacetic acid and trichloroacetic acid were high in river water for supplying drinking water while the concentration of tribromoacetic acid was high in river water containing sea and waste water.
On the other hand, the total concentration of all halogenated disinfection by-products in tap water in special districts of the mainland and OG districts of the islands was about 50-140 ng/ml (mean, about 100 ng/ml) . According to the classes of halogenated by-products, haloacetic acids and trihalomethanes were major by-products, and their concentration was about 15-90 ng/ml (mean, about 20-65 ng/ml) . Haloacetonitriles, haloacetones, and haloacetaldehydes were medium by-products with their concentration being about 1-15 ng/ml (mean, several-slightly less than 15 ng/ml) . Halonitromethanes and halopropionic acids were minor by-products, and their concentration was under 2 ng/ml . Concerning individual halogenated by-products in each class, halogenated by-products in tap water derived from river water were mainly chlorine series, and those in tap water derived from river and ground water containing sea and waste water were mainly bromine series.The concentrations of all individual halogenated by-products were lower in tap water purified by advanced water treatment than in tap water purified only by chlorination.
Similarly, the total concentration of all halogenated disinfection by-products in tap water in non-special districts of the mainland and OH districts of the islands was about 5-70 ng/ml (mean, about 25 ng/ml) . According to the classes of halogenated by-products, haloacetic acids and trihalomethanes were major by-products and their concentrations were about 0.5-40 ng/ml (mean, about 3-20 ng/ml) . Haloacetonitriles, haloacetones, and haloacetaldehydes were medium by-products and their concentrations were below the detection limit-about 30 ng/ml (mean, about 0.5-3 ng/ml) . Halopropionic acids and halonitromethanes were minor by-products and their concentrations were under 1 ng/ml. Concerning individual halogenated by-products in each class, halogenated by-products in tap water derived from river water were mainly chlorine series, and those in tap water derived from river water containing sea and waste water were mainly bromine series.
The difference in the concentration of halogenated by-products between tap water and raw water was very marked in the special districts of the mainland and the OG districts of the islands. However, compared with these districts, the difference in the concentration of halogenated by-products between tap water and raw water was slight in the non-special districts of the mainland and the OH districts of the islands.

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