The data of atmospheric PCDDs and PCDFs, determined by HRGC/HRMS in 1996 and also by HRGC/LRMS in 1986-1994 in Osaka, were analyzed to clarify compositions of their congeners in summer and winter and effects of wind and emission sources on the concentrations. In 1996, penta- and hexachlorinated PCDDs and PCDFs were found to be major, and to contribute mainly to the respective total TEQs. The concentrations of PCDDs and PCDFs in 1986-1996 were relatively high at 1.5-2.0m/s of averaged wind speed. In some urban areas, the data showed that PCDDs and PCDFs were distributed in higher concentrations down the wind of urban garbage incinerators.

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Adsorption and desorption isotherms of Simazine on a decomposed granitic (DG) soil, two natural loam soils, and selected soil particle size fractions were measured in batch experiments. Soil-water content (air-dry compared to oven-dry) markedly influenced the amounts of simazine adsorbed and desorbed on the low-organic DG soil and its soil size fractions while only slight effects were observed for the higher-organic loam soils and their soil size fractions. Decreasing adsorption and increasing desorption with increasing pH was observed for all soils. For both DG and loam, the largest soil size fraction (1.0-2.0 mm) was the most effective adsorber based on unit surface area. The Freundlich isotherm equation well described the measured adsorption and desorption data. The Freundlich adsorption and desorption coefficients (k_{f, a} and k_{f, d}) were both highly correlated with specific surface area for the DG and soil organic matter content for the loam. Also, k_{f, d} was highly correlated with k_{f, a} Three step desorption experiments gave a final desorption of simazine from the DG soil and its size fractions between 91-95 % of the total amount initially adsorbed compared to only 12-22 % for the loam soils and their size fractions. Minor sorption hysteresis was observed for DG. Large hysteresis effects were seen for the loam soils where the hysteresis index was controlled by the soil organic matter content. The difference in sorption characteristics and hysteresis for the two soil types was confirmed in micro-column transport experiments, where significant retardation and tailing of the simazine effluent concentration curve was observed only for the loam soil.

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An analytical condition of ICP-MS has been developed for precise and rapid determination of thallium in environmental samples. The sample was digested with HF/HNO₃/HClO₄, then thallium was determined by calibration method. Platinum was found to be effective as an internal standard to correct for the non-spectroscopic interference.
Analytical results of 7 certified reference materials showed good agreement with the certified or reference values. The analytical precisions of Buffalo River Sediment and JLK-1 were both 0.8%.
Thallium was detected in the range from 0.25 to 0.47μg/g in sediments and fly ash, 1.2 to 1.9μg/g in sewage sludge and suspended particulates.
The determination limit (10σ) was 0.0012μg/l in solution or 0.0012μg/g in environmental samples.

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The oil-tanker, Nakhodka was wrecked in the Sea of Japan in January, 1997. The oil-spill from the vessel's damaged tanks polluted the coastline of Ishikawa prefecture. In order to evaluate the oil-degrading potential of coastal areas and to develop bioremediation techniques, surveys the distribution and numbers of hydrocarbon-degrading bacteria (HDB) and degradation of spilled oil by micriobial populations in sea water at the oil-polluted sites of Ishikawa were carried out. The numbers of HDB ranged from 10²-10⁴ MPN 100 ml^-1 of sea water during the 11 months after the spill at 2 sampling points. In the laboratory experiments, degradation activity of the Nakhodka's heavy fuel oil, spilled oil and weathering oil attached to sand by microbial populations in sea water was examined on the basis on the rate of reduction of the components in heavy oils. In regards to oil-biodegrading ability, the percentage and rate of reduction was 17 % and 3.3g/m³ sea water/day on weight of exracts with dichloromethane and 33% and 5.2g/m³ sea water day on weight of extracts with n-hexan-extract, respectively. The addition of nutrients (N, P) enhanced the biodegradation of the Nakhodka's heavy fuel oil and the spilled oil by microbial populations in sea water. Adding nutrients to the sea water sample doubled rate of reduction of exracts with n-hexane from the Nakhodka's heavy fuel oil and spilled as compared to those without nutrients. Concerning the components of heavy oils, the decomposition percentages of n-paraffins, dibenzothiophene, pyrene, fluoranthene were 62 %, 100 %, 63 %, 68 % and 81 % respectively after 38 days of incubation at 20 °C.. In conclusion, it is suggested that biostimulation treatment by adding nutrients would be able to accelerate oil removal from oil-polluted coasts.

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Measurement method for gaseous and particulate Polynuclear Aromatics (PNAs) using quartz fiber filter and adsorbent (Empore Disk) was investigated. At 25 degrees, the recoveries of Fluoranthene, Pyrene, 2, 3-benzofluorene, Chrycene, Benzo [e] Pyrene, Benzo [a] Pyrene, Perylene, Benzo [g, h, i] Perylene, Dibenzo [a, h] Anthracene and Coronene, which were spiked on quartz fiber filter, were 97%, 102%, 45%, 90%, 105%, 16%, 31%, 93%, 93%, 105%, respectively. Similar results were obtained at 40 degrees. B [a] P-d12 spiked on quartz fiber filter was oxidized to corresponding quinones after drawing air through the filter for 24hours, which can explain low recavery of B [a] P. PNAs in ambient air and incinerator exhaust gas were determined with the method.

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An analytical procedure using two cartrides coated with 2, 4-dinitrophenyl hydrazine (DNPH) in series has been developed for the determination of crotonaldehyde in air. Air sample was collected on the DNPH-silica cartridge with an ozone scrubber, which was heated with a pocket heater to remove the loss of crotonaldehyde. The detection limit and quantification limit for crotonaldehyde were 4 and 14 ng/m³;, when air sample was collected at 0.1l/min for 24-h. The warming effect with a pocket heater was also observed in the case of formaldehyde and acetaldehyde.

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Low flow rate cascade impactors were developed to measure indoor airborne particulates simply. The airborne particulates were size fractionated by a 3 stage cascade impactor (larger than 10μm, 2.5-10μm and smaller than 2.5μm) . Flow rate was 3.0l/min or 25l/min. To examine the accuracy of this method, simultaneous measurement of particulate and polycyclic aromatic hydrocarbons (PAHs) concentrations were performed by using this cascade impactor and a TEOM particulate monitor which was the standard device for measuring particulate concentration.
(1) Concentrations of indoor airborne particulates collected by this cascade impactor were almost same as those of the standard method using the TEOM in a tabacco-smoked room or less contaminated room.
(2) PAH concentrations in indoor airborne particulates collected by the cascade impactor were also same as those of standard method using the TEOM. The order of size-fractionated PAH concentrations in indoor airborne particulates were as follows; larger than 10μm<2.5-10μm< smaller than 2.5μm.
(3) Coefficient of variations (CV) of particulate concentration were below 8.8% if the mass of collected particulates were more than about 50μg. CV of PAHs concentration were also excellent. These results suggest that the low flow rate cascade Impactor developed in this study is a simple and useful method for measurement of fine airborne particulates.

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The amounts of ozone generated from air cleaners were determined for 14 air cleaners that were available on the market. Elimination rates of ozone were also measured after the air cleaners stopped. Ozone generation was observed from some electrostatic precipitation system. These generation rates varied from 316 to 5100μl/hour. Seasonal variation of ozone generation rates, degeneration of ozone by deodorant filter and correlation between ozone generation rates and voltages on the ionizer were investigated using several air cleaners that generated ozone considerably. Ozone concentrations were measured in chamber and actual rooms, and the results were compared with each other. The results obtained were as follows; ozone generation rates in summer was lower than that of winter. Deodorant filter could degrade ozone. The ionizer that have negative potential generated much more ozone rather than that have positive potential.
Ozone concentration in actual rooms were significantly lower than that in chamber when the air cleaner worked on. Ozone elimination rates in actual rooms were also higher than that in chamber after the air cleaner stopped, because ozone could react various chemicals in actual rooms. Ozone concentration, however, exceeded 60 ppb (the environmental quality standard of ozone in Japan) in actual rooms when the air cleaner that had highest generation rate of ozone was used.

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We have developed quartz crystal resonator (QCR) sensors coated with gas-sorption films produced by radio-frequency sputtering of porous sintered-polyethylene (PS-PE), polychlorotrifluoroethylene (PCTFE), and biomolecules including amino acids. We have measured the sensing capabilities of these sensors for vapors of gasoline, fuel oil, and their ingredients at ppb level. The sensing capabilities of PS-PE sensors were profoundly affected by the sputtering conditions; they were enhanced by the photo-excitation effect, and were reduced by carbonization and water treatment. The photo-excited PS-PE sensor was so sensitive that it could detect linear hydrocarbon (>C₁₂) vapors below the ppb level. The time constant of the sorption curve, however, was large, indicating a slow sensing speed. Amino-acid-film-coated sensors showed poor detection capabilities and PCTFE-film-coated sensor showed negligible sensing signals for the test vapors. The PS-PR film had higher affinities for organic vapors than for water vapor, and therefore is thought to be useful for environmental sensing.

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Effect of preincubation time and density of bacterial suspension on the sensitivity of Kado's microsuspension assay (modified liquid incubation assay) were studied by using Salmonella typhimurium TA100 and extract of airborne particles.
Detection sensitivity increased in proportion to the cell concentration in the range from 1.3×10⁸ cells/ml to 1.4×10¹⁰ cells/ml. It showed 7 times higher sensitivity than that of the lowest density (1.3×10⁸ cells/ml) when a high cell density (1.1×10¹⁰ cells/ml) was used. Prolonged preincubation (50-140 min) increased the sensitivity at a higher cell density. At the highest cell density employed, cell growth was suppressed probably due to evaporation of water during the preincubation. Employment of seal to the microvial showed the good result. These modifications gave us more sensitive and useful mutagenic test with very small amount sample.

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Nowadays, automotive exhaust carbonyls are collected as 2, 4-Dinitrophenylhydrazine (DNPH) derivertives and mostly analysed by high performance liquid chromatography with ultra violet detection. In this study, sensitivities, reproducibilities, suitable wavelength for detection, and stability with elapsed time on the sample tray of DNPH-aldehydes analysed by high performance liquid chromatography are investigated.

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