A statistical analysis was carried out to evaluate the relationship between NO₂ concentration and traffic density. Environmental monitoring NO₂ concentration data were obtained by diffusive sampler method between April, 1989 and March, 1993 at 22 monitoring site in Sendai City.
The average monthly NO₂ concentration at all the sites ranged from 14.4 ppb to 38.9 ppb (mean, 27.2 ppb) . The annual distribution of monthly adjusted treatment means for NO₂ concentration formed a V-shaped curve, with the lowest value observed in August and the highest in March. The pattern of monthly change of NO₂ concentration in Sendai City was similar to that reported for areas with high atmospheric NO₂ concentration. Analysis of covariance revealed the greatest effect for traffic density. The partial regression coefficient for traffic density was 2.2×10^-4 (ppb/vehicle), indicating that an increase of NO₂ concentration on the order of 2.2 ppb could be predicted for every traffic density increase of 10, 000 vehicles. The partial regression coefficient for distance to the road was -0.1 ppb/m. Partial regression coefficient for measurement year was significant and showed positive value (0.32 ppb/year) . However, the magnitude of annual increase (1.2%) is low. About 63% of the total observed variance could be accounted for by the mathematical model used in this study.

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Organophosphoric acid triesters (OPEs) in the leachate from Osaka North Port Sea-Based Solid Waste Disposal Site and in the surrounding seawater were examined.
OPE concentration in the leachate was ten to a hundred times higher than that in the surrounding seawater. In the leachate from Sitel, TCEP showed the highest concentration (0.4-30μg/l), with concentration of the other OPEs (TCPP, TEP, TBP, TDCPP, TPP, TBXP) ranging from 0.1 to 17.0μ g/l. Because of the low level of biodegradation activity resulting from the anaerobic and reducing conditions, no notable decrease in OPE levels was observed inside the waste disposal site. In the leachate at dredged soil disposal sites (Sites 2 and 3), however, OPE concentrations were relatively low, being the same as those in the surrounding seawater. The composition of OPEs in the leachate at waste disposal site was different from that in the surrounding seawater, and might reflect the general characteristics of the leachate from waste disposal sites.

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Estimation of factors affecting SPM concentration was carried out by statistical analysis using the data obtained from air pollution monitoring stations. Data used in the analysis were extracted from six monitoring stations in Sendai City in the 1992 fiscal year (number of data was 52, 560: defined as the“whole year data”) . The yearly mean value was 0.030mg/m³, which was almost equal level to the national average (0.038mg/m³) . The result of the analysis of variance shows that the fluctuation among monitoring stations is large, especially on the“high concentration days' data (n=1, 296) .” SPM was greatly influenced by temperature in the“whole year data, ” but not in the“high concentration days' data.” It was found that SPM concentration was correlated negatively to the wind velocity, positively to the temperature and the difference of vertical temperature through the analysis of partial regression coefficients of each meteorological condition and air pollutant. In the case of the analysis considering the effects of other pollutants, the fluctuation of SPM was affected conspicuously by NO and NO₂, but the effect of the month of measurement and temperature became small. This may show that the level of nitrogen oxide greatly affects the fluctuation of SPM in Sendai City.

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Strain H2-5, a gram positive and rod bacterium which was capable of degrading pyrene, was isolated from soil. The bacterium was positive for acid-fast staining. The optimum growth temperature was 34.3°C, and the upper limit temperature for the growth was around 45°C. At low concentration (1.3 μg/ml) of polycyclic aromatic hydrocarbons (PAHs), H2-5 cells (45μg dry weight/ml) grown on TSB degraded 90% of pyrene in 12 hr, and degraded 60% of Benzo (a) pyrene (BaP), 25% of Benz (a) anthracene (BaA), and 8% of Benzo (ghi) perylene (BghiP) in 3 days. At high concentration (26.7μg/ml) of PAHs, H2-5 cells (226μg dry weight ml) grown on TSB degraded more than 80% of pyrene and BaP, 40% of BaA, and 30% of BghiP in 11 days. Mixture of cells (5.4μg dry weight/ml) grown on pyrene-enriched culture, from which H2-5 was isolated, degraded pyrene more rapidly at early reaction stage, but less effectively at later stage, than the isolated H2-5 (226μg dry weight ml) grown on TSB, and both degraded 90% of pyrene in 11 days.

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A new method for the calculation of polychlorinated biphenyls (PCBs) by an ECD-GC tech-nique using a Supelco SPB-5 capillary column was developed. A mixture of Japanese commercial PCB products (Kanechlor 300 : 400: 500 : 600=1: 1: 1: 1) was used as a standard for the determination. This method enabled the separate quantification of 78 peaks resulting from PCB constituents in the ECD-GC chromatogram. The comparison of total PCB concentrations in four samples of fish and human adipose tissue revealed that our analytical data are in good agreement with those obtained by the official method using an OV-1 packed column, and showed the concentration ratios of PCBs analysed with a capillary column versus those obtained by a packed column method to be in the range of 0.85 to 1.17 with an average of 0.96.
In addition, the combination of this method with GC MS analysis makes it possible to deter-mine 103 PCB congeners.

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A study was carried out on the runoff of four fungicides used for prevention of snow molds in actual golf course, model green and model fairway.
Oxine-copper and tolclofosmethyl were analyzed in effluent water from the flow-control pond in the actual golf course. Oxine-copper was detected only in a few days after rainfall and tolclofosmethyl was detected during the period examined (from November to April) .
In model green experiments, tolclofosmethyl was detected at very low level in leaching water. On the other hand, isoprothiolane and flutolanil applied in the previous year were detected at the same levels as the previous experiments. Oxine-copper was not detected in leaching water.
In model fairway experiments, oxine-copper, tolclofosmethyl, isoprothiolane and flutolanil were detected at high concentration in surface water. The concentration of oxine-copper de-creased rapidly by repetition of watering.

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A simple mutagenicity detection method for gaseous compounds in tobacco smoke was examined as a part of study for the evaluation of mutagenicity of air pollutants. A main stream and a side stream of tobacco smoke were introduced separately to impinging tubes containing bacterial solutions and bubbled them. The mutagenicity was estimated by the umu test using Salmonella typhimuriumOY413 and TA1535/pSK1002 strains. The enzymatic activity obtained by the umu test was corrected with the survival rate of the tester strains which was evaluated by testing the strains to hydrogen peroxide. The correction by the plate spread method gave more exact mutagenicity than the conventional correction with absorbance at a wavelength of600 nm. For the detection of the mutagenicity of the gaseous compounds in the tobacco smoke, it was required to connect 6 impinging tubes in a series. The gaseous compounds showed lower mutagenicity than the particles containing in the tobacco smoke both for the main stream and the side stream of the tobacco smoke.

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Polychlorinated biphenyls (PCBs) were measured in surface sediments and sediment cores from Masan Bay of Korea. Samples were digested with 1N KOH / EtOH, extracted and cleaned up by silica gel and Florisil PR column chromatography. The recoveries of chemicals were more than 93%. The quantative analyses were carried out by gas chromatograph-electron capture de-tector (GC-ECD) equipped with a capillary column. PCBs concentrations of surface sediments ranged from 8 to 210ng / g.
PCBs were also detected in the core samples analyzed. As a result of the investigation, we estimated that PCBs might be used industrially from the 1950s in Korea, because the PCBs contaminantion level remarkably increased in the late 1950s part on the samples. This study is invaluable due to the first investigation about the environmental pollution and situation by PCBs in Korea.

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A big gust, which was suddenly broken out in Gansu desert area on 5th May 1993, gave the heavy disaster in many places. This gust was transported by the strong wind to Xian after 1 day, and its particles were collected with a plastic thin sheet in the suburbs of Xian. The gust particles and the loess particles in Xian were analyzed after acid digestion for bulk concentration of many elements, and were also analyzed by X-ray photoelectron spectrometry for the chemical state of sulfur at the particle surface and for the surface composition of major elements in particles. The lower concentration ratios of alkaline elements, especially calcium, to aluminium in the gust particles compared with those in the Xian loess were thought to be due to weathering. Sulfur has been found to be present as sulfate form rather than the sulfide in the gust particles as well as Xian loess particles and Kosa aerosols. Sulfur to calcium ratios are higher at the sur-face than in the bulk of gust particles, indicating that sulfur tends to be rich at the surface of the particles.

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Five original Kosa soils, collected in the locations of being thought to be the origins of Kosa aerosol in China, were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) to determine the lead isotope ratios²⁰⁷Pb: ²⁰⁶Pb and ²⁰⁸Pb: ²⁰⁶Pb. To minimize mass bias and drift in Pb isotope measurement, the mass discrimination correction, based upon the addition of thallium to the samples and measurement of ²⁰⁵Tl: ²⁰³Tl ratio, was used. At the same time, concentrations of 12 elements were determined as a function of particle-size by ICP-MS and inductively cou-pled plasma atomic emission spectrometry (ICP-AES) .

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Atmospheric concentrations of α, ω-dicarboxylic acids (succinic acid, glutaric acid and adipic acid) were measured at eight National Air Sampling Network (NASN) sites. Atmospheric particulate matter samples had been collected on quartz fiber filters by a high-volume air sampler during April 1991 to March 1992. Dicarboxylic acids in the samples were analyzed by direct determination method using pyrolysis-methylation technique. Succinic acid was the dominant species, followed by glutaric acid and adipic acid. Average concentrations of succinic acid, glutaric acid and adipic acid ranged 0.063-0.19, 0.019-0.056, and 0.007-0.033 μg / m³, respectively.
The obtained data were analyzed by the following two means : 1) comparison with the ratio of organic carbon (OC) / elemental carbon (EC) and dicarboxylic acids (DCA) / EC, 2) regression analysis between DCA's concentrations to EC and NO^-₃ concentrations. As a result, it was suggested that origins of DCA were both secondary formation via photochemical reaction from primarily emitted hydrocarbons such as cycloalkenes and diolefins, and direct emission by combustion of fossil fuels. Though most of atmospheric DCA were regarded as secondary forma-tions, these results suggested the existence of direct DCA emissions.

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