A new methods have been developped for the determination of nitrite in the environmental water samples by HPLC with post-column and the flow injection analysis (FIA) using diazotization reaction.
The optimum temperature and reaction time were investigated on the diazotization reaction of nitrite.
We could detect 0.001ppm of nitrite by HPLC and FIA using diazotization reaction and spectrophotometric detection where 540 nm of wave length was used. But it was observed in this method that some interferences existed.
Finally, we determined successfully nitrite in samples conteining high concentration of chloride such as tap and sea water by post-column HPLC using derivarization with diazonium salt.

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Cartap in air, which was collected on the Carbotrap^TMsorbent and introduced into GC/MS by using the TCT instrument, was determined as nereistoxin. The analytical method for thiophanate-methyl in air was composed of sampling with the ascorbic acid-impregnated paper and high-performance liquid chromatography with UV detection. The detection limit of nereistoxin was 0.3ng/m³for 30L of air sampled, and that of thiophanate-methyl was 22ng/m³for sum of 5 samples, where 200L of air was collected in each. Both compounds were not detected in any samples.

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Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in indoor air after cigarette smoking were determined by high resolution gas chromatography/high resolution mass spectrometry. Concentrations of total PCDDs and PCDFs in control indoor air were 4.65 and 6.08pg/m³, respectively. Concentration of PCDDs and PCDFs in indoor air where 20 cigarette were smoked for 7 hour were 10-30% higher than those in control indoor air. Cigarette were smoked at a rate of l cigarette/min by using a cigarette-smoke generator. After 20 cigarette were smoked, concentrations of PCDDs and PCDFs in the indoor air were 8.6 and 6.8pg/m³, respectively. This level was 1.4 times higher than that in the control indoor air. After 100 cigarette were smoked, concentrations of PCDDs and PCDFs in the indoor air were 13.6 and 8.3 pg/m³, respectively. This level was 2 times higher than that in the control indoor air. The increase of daily intake of PCDDs and PCDFs by passive smoking was estimated 0.7pg/person/day as2, 3, 7, 8-TCDD equivalent, which is around 250 time less than daily intake of total PCDDs and PCDFs as 2, 3, 7, 8-TCDD equivalent.

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An analytical method of pesticide intermediates, methyl 3, 3-dimethyl-4-pentenoate and 3-chloro-4-fluoronitrobenzene, in atmosphere has been developed. Those compounds in atmosphere were collected by using a commercially available polystyrene gel cartridge (Sep-Pak Plus PS-1) and then were eluted with 5mL of hexane from the catridge. They were concentrated and analyzed by high-resolution gas chromatography/mass spectrometry using selected monitoring technique. The detection limits of methyl 3, 3-dimethyl-4-pentenoate and 3-chloro-4-fluoronitrobenzene were 1.0 and 0.3ng/m³, respectively. The recoveries of methyl 3, 3-dimethyl-4-pentenoate and 3-chloro-4-fluoronitrobenzene were 97.8% and 96.0%, respectively. Humidity of air and small temperature variation did not affect collection efficiency.

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A capillary column gas chromatography/mass spectromertic procedure is described for the determination of molinate, which is a representative thiocarbamate paddy herbicide, in environmental samples. A liquid-liquid extraction method with hexane is applied to the separation and concentration of molinate residues in water samples. On the other hand, the pretreatment technique for sediment and fish samples is combined with steam distillation and column chromatography using a Sep-Pak Florisil cartridge. The detection limits in water, sediment and fish samples are 12ng/l, 380ng/kg and 520ng/kg, respectively. The recoveries of molinate from water samples spiked (60ppt) and sediment samples spiked (3ppb) are more than 90%, and those from fish samples spiked (3ppb) are about 80%. This method enables the reliable determination of molinate residues in environmental samples at ppt or ppb level.

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A method for the determination of toluenesulfonamides in environmental samples such as river waterand bottom sediment has been developed. Toluenesulfonamides in river water were extracted with ethy acetate, and ones in bottom sediment with acetonitrile. The extracts were cleaned up by florisil column chromatography and determined by capillary gas chromatographicmass spectrometry (GC/MS) . The determination limits on river water were 0.30μg/l for o-toluenesulfonamide and 0.29μg/l for p-toluenesulfonamide. The detection limits on bottom sediment were 0.96μg/kg for o-toluenesulfonamide and 0.60μg/kg for p-toluenesulfonamide. The recoveries from river water and bottom sediment were over 90% with coefficient of variation below 6%. This method shows sufficient sensitivity, selectivity and accuracy to be applied to environmental samples.

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Simultaneous analytical method of acetonitrile and acrylonitrile in environmental samplessuch as water and sediment by capillary gas chromatograpy/mass spectrometry using isotopedilution technique has been developed. Trace acetonitrile and acrylonitrile in environmental samples are steam-distilled and extracted with dichloromethane. Recoveries of both compounds weresatisfactory.
Contamination of water and solvent with acetonitrile was observed. Detection limits of acetonitrile were 0.3μg/l in water and 3.8μg/kg (dry weight) in sediment and detection limits ofacrylonitrile were 0.1μg/l in water and 1.6μg/kg (dry weight) in sediment.
In the application of this method to actual environmental samples, acetonitrile was detectedin river water, sea water and sediment.

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It is very important to study toxic chemical substances formed from hazardous wastes by combustion. Most of the wastes are disposed on landfill or incinerated. Regarding the formation ofchemical substances produced during the incineration process, many aspects are still unknown including the mechanism of formation. We have investigated the formation of semi-volatile chlorinated organic compounds in waste incinerators. Polychlorinated phenols (PCPs) and polychlorinated benzenes (PCBzs) were analyzed by HRGC/MS-SIM and the PTRI data of all congeners were calculated. Vapor-phase components and components bound on particle in the stack gas were sampled. The circulating water for scrubber, cooling water and NaOH solution for desulfurizing apparatus were also sampled. Components in aqueous phase and components bound on particles were analyzed individually. PCBzs and PCPs isomer contents were determined and isomer contents of polychlorinated naphthalenes (PCNs) were evaluated. Isomer patterns of those compoundsin the circulating water suggested that 2, 4, 6-trichlorophenol was dominant among trichlorophenol isomers. Most of volatile chlorinated hydrocarbons which was discharged from disposal facility would be emitted into exhaust gas. On the other hand, high-boiling point organiccompounds would exist on particles or in aqueous phase in the circulating water and be hardly emitted into the atmosphere as exhaust gas components.

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In the rain water analysis, developments of rapid analysis methods have been required.
In this paper, we examined a rapid analysis of anions in rain water using capillary electrophoresis (CE) .
The analytical time for three anions (Cl^-, NO₃^-and SO₄^2-) in rain water by the CE method, was within 3 min, whereas the analytical time for the three anions by ion chromatography (IC) as a standard method, was necessary at least 8 min.
Correlation coefficients between CE and IC were over 0.99. The coefficient of variation of retention time in IC method was slightly smaller than that of migration time in CE method.
These results suggest that the CE is a useful method for the analysis of components in rain water for its rapidity and reproductivity.

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Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs) in aerial deposition were investigated. The dry-wet deposition (total amounts of dry and wet deposition) was collected into the jug with a glass funnel opened over a sampling period, and the wet-only deposition was collected into the jug equipped with a automatic wet-only collector. The concentration of total PCDDs and PCDFs in the dry-wet deposition were 91-559pg/l, and those in the wetonly deposition were 34pg/l and 25pg/l, respectively. The PCDD/PCDF fluxes in the dry-wet deposition were estimated to be 436-1206ng/m²/year (3.5-13.7ng (TEQ) /m²/year), and those in the wet-only deposition were 56ng/m²/year and 42ng/m²/year (0.10ng (TEQ) /m²/year and 0.13ng (TEQ) /m²/year, respectively) . The PCDD/PCDF fluxes for the dry-wet deposition were evaluated to be 10-30 times (30-100 times, TEQs) higher than those for the wet-only deposition. These results suggest that the dry deposition is the predominant pathway of PCDDs/DFs removal from the atmosphere.

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Gas chromatography/mass spectrometry is the best method for identification of unknown compounds in environmental samples. The most convenient technique for identification is a use of library search system. But commercially available search system and data base of mass spectra have several disadvantage such as wrong spectra or insufficient search algorism. Therefore, a new library search system has been developed in this study. In this part of our report, studies performed in the Okayama Prefectural Institute for Environmental Science and Public Health are described. Furthermore, a new technology has been established for correction of mass spectra which are significantly different from mass spectra in data base because of difference of instruments used and operational conditions. Evaluation of the new system in actual environmental analysis and crosscheck were performed and satisfactory results were obtained.

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