A comprehensive retention and selectivity characterization of five hydrophilic interaction chromatography (HILIC) stationary phases was performed with seven polar pesticides (acephate, methamidophos, asulam, mecoprop, triclopyr, dalapon and amitrole), in order to study the effect of surface chemistry and mobile phase composition on chromatographic behavior and ESI-MS response. Selectivity differences were compared for all columns operated in neutral condition. Additionally,the influence of mobile phase condition on retention behavior was studied for each column. In our results, an increase of the percentage of organic solvent in the mobile phase led to an increase of the retention factor and the number of theoretical plate for all analytes and all columns, whereas the significant differences in the effect of salt concentration were observed for different stationary phases. In addition, moderate differences in selectivity were observed on the same column operated at different pH, especially in acidic compounds. In general, higher column temperature led to weaker retention and, however, the decreasing rate of retention time depended on the characteristics of stationary phase and target compound. In some case, the retention increased with the temperature on HILIC column. The data from this study can be used to establish guidelines for rapid HILIC method development of polar compounds.

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This paper reports on a one-month sampling method using a low-volume air sampler (LV-1M) for long-term monitoring of dioxins and polychlorinated biphenyls (PCBs) in ambient air. The effectiveness of an activated carbon fiber felt(ACF) for sampling of PCBs, particularly low chlorinated PCBs, was examined. Atmospheric dioxins were quantitatively collected using a quartz fiber filter and two polyurethane foams (PUFs), but low chlorinated PCBs could not be accurately sampled using PUFs, particularly in the summer season. Accordingly, it was found the use of ACF is very effective for accurate monitoring. In addition, the quantitative results of the LV-1M method were comparable to those of the one-week sampling method using a high-volume air sampler, which is the official method for monitoring dioxins in ambient air. This finding indicates that it is possible to monitor atmosphere through the LV-1M method at a sufficiently precise level. Using this LV-1M method, ambient air was continuously monitored for 5-6 years in the city of Sapporo and Muroran. From the monitoring results, it was observed that although the amount of dioxins in Muroran is decreasing every year, the concentration of dioxins increases from autumn to winter and the concentration of PCBs increases in summer and decrease in winter as an effect of the change in air temperature.

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In the present study, variations in daily PAH concentrations were investigated in relation to meteorological data and concentrations of other air pollutants in order to verify the effectiveness of the current estimation method. From January 2000 to March 2001, airborne particulates were collected at one site in Okayama, Japan, for 24 h on 7 days each month using a high-volume air sampler equipped with a quartz-fiber filter. The sampling site is in a rural area; however, because the Mizushima industrial zone is located about 15 km southwest of the sampling site and national highway 2 is located about 5 km north of the sampling site, the site usually has high PAH concentrations. From the 105 samples obtained at the sampling site, 23 kinds of PAHs were measured by the gas chromatography/mass spectroscopy (GC/MS) method, and the daily concentrations of 16 out of the 23 kinds of PAHs in air were obtained. As a result, large differences in daily total PAH concentrations, which ranged from 0.69 to 83 ng/m³, were observed at the sampling site. This result suggested that the current estimation method was ineffective. For example, there is a possibility of higher health risks being overlooked if the PAH concentrations are not measured on days on which the concentrations are high. Investigations of the relationship between PAH concentration and meteorological data such as wind direction and wind velocity revealed that the PAH concentrations were significantly and positively correlated with the number of hours per day of southwest wind and that the PAH concentrations were significantly and negatively correlated with the average wind velocity. This result implies that the PAH concentrations in air will be influenced by the Mizushima industrial zone, and that the PAH concentrations will be high on days experiencing southwest wind and low wind velocity at the sampling site.

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In the present study, the mutagenicity of chlorinated cow dung was measured by the Ames preincubation method using S. typhimurium TA100 and the TA98 strain. It was found that chlorination might induce mutagenicity in cow dung, and it could be detected without S9mix. Analysis revealed that the most reliable conditions for analyzing this effect, might be the use of extracts of dung chlorinated at 20°C for 2 hours with 6% chlorine solution. When the mutagenicity of five samples of chlorinated cow dung and three samples of chlorinated horse dung were measured under these conditions, there was no difference in mutagenicity between individual cows and individual horses. In general, mutagenicity sensitivity of the TA100 strain tended to be higher than that of the TA98 strain.

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A highly sensitive analytical method of epichlorohydrin (ECH, 1-chloro-2,3-epoxyethane) using derivatization, solidphase extraction, and liquid-chromatography/mass spectrometry was applied to river and sea waters. The aminolysis reaction of 3,5-difluorobenzylamine with ECH was effective as derivatization. The derivative obtained was enriched by solid-phase extraction and quantitated by liquid chromatography/mass spectrometry. The reaction of derivatization and preparation of solutions of volatile ECH were optimized. Method detection limit (MDL) was determined by the examination of fortified environmental samples. The MDL of ECH was 0.003 μg/L for actual environmental samples spiked at 0.03 μg/L (the detection limit, prescribd by analytical method of Monitoring Substances in water environment). The recovery of ECH was over 90% (n =7). ECH was detected in only one station out of 20 in Osaka city rivers and estuaries at a concentration of 0.2 μg/L.

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