From April to November in 2008, we observed altitudinal and seasonal changes in the monthly mean ozone concentrations using passive samplers at two mountains in Niigata Prefecture: Mt. Bunagahira on Sado Island and Mt. Hakkai, located on the mainland. The mean ozone concentrations at both mountains were the highest in spring (May), and decreased in summer. The ozone concentrations at Mt. Bunagahira increased in autumn again. Such a seasonal change in the mean ozone concentrations was the same pattern observed at other mountains in central Japan as well as plains in western part of Japan. The monthly mean ozone concentrations increased with the altitude at Mt. Hakkai. Such an altitudinal change in ozone concentrations was the similar pattern observed at other mountains in central Japan. In contrast, the mean ozone concentrations of each month showed similar values at all altitudes on each slope side of Mt. Bunagahira showing a different tendency with other mountains observed in Japan. This phenomenon might be resulted from few local origins of air pollutants around Mt. Bunagahira that generate or decompose ozone. The mean ozone concentrations on the slope of Mt. Bunagahira facing northwest were higher than those facing southeast in every month. This phenomenon might suggest that the mean ozone concentrations transported from the direction of East Asian continent were higher than those of the mainland in Niigata Prefecture.

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Brominated flame retardants (BFRs) leaching in water (for 24hours), amylase aqueous solution (for 24hours) and ethanol (for 10) minutes from 18 kinds of babies′ toys were determined by LC/MS, and the some other chemicals were identified by LC/ToFMS. The aim of the study is to determine or identify chemicals leaching from baby toys with a method roughly simulating baby′s behavior of licking, sucking or biting. Bisphenol A leaching in water and ethanol were 3∼430ng/item and 1.3∼92ng/item, respectively. Tribromophenol leaching in water, amylase aqueous solution and ethanol were 13∼220ng/item, 0.5∼200ng/item and 0.1∼0.2ng/item, respectively. Tetrabromobisphenol A leaching in water, amylase aqueous solution and ethanol were 5.0∼590ng/item, 0.4∼6.9ng/item and 2.3∼4.4ng/item, respectively. Hexabromocyclododecane diastereoisomers were not found in water in the limit of detection of 1ng/item, however those in amylase aqueous solution and ethanol were 3.0∼18ng/item and 0.6∼25ng/item, respectively. Chemicals identified in the leachates by LC/ToFMS were a nucleating agent, a light stabilizer, an intermediate in organic syntheses which were plastic synthesizers for food package, plastic lens, liquid crystal and other plastic items, and lubricants. It is suggested that most of plastic baby toys would be contaminated with BFRs and various chemical additives not used for baby toys.

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Perchlorate concentrations in raw and tap water in Osaka, Japan, were determined by IC-MS/MS. The concentrations of perchlorate in raw water and tap water were in the ranges from <0.015 to 0.48 μg/L and from <0.015 to 0.82 μg/L, respectively. Except for only a few cases, the perchlorate concentration in each tap water sample was at nearly equivalent level to that in the corresponding raw water. The results indicate that perchlorate in raw water was not removed effectively by the ordinary water treatment methods such as ozonation, granular activated carbon adsorption, rapid and slow sand filtrations. On the other hand, perchlorate was found to be contained in sodium hypochlorite solutions, used in the chlorination process, at wide concentration range between 4.9 and 5900 μg/L. In the case using disinfectant with the highest perchlorate content, the significant increase in perchlorate concentration in tap water was observed, compared to that in raw water. However, when 2 L of tap water was ingested every day, the corresponding perchlorate intake was estimated to be at most 1.8 μg/day from the observed perchlorate concentrations in tap water samples. This value was sufficiently lower than the calculated daily intake for a person weighing 50 kg from reference dose value of perchlorate. Therefore, the health risk to humans from perchlorate in tap water in Osaka, Japan, is very low.

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The author compared the six pretreatment methods for the analysis of PCBs in marine sediment, including the warming alkaline treatment method. The results of the six pretreatment methods showed nearly equal total PCBs concentration, but the analysis for each homologue and each congener indicated that in the case of the warming alkaline treatment method, high chlorinated congeners decreased and the amount of low chlorinated congeners was significantly low compared with the other methods. The other pretreatment methods showed almost the same results for each homologue and each congener, and surrogate recoveries were good. In addition, it was found that the pressurized liquid extraction with toluene-room temperature alkaline treatment method and the Discovery^®Ag-ION SPE tube-based treatment are effective for removing impurities, such as mineral oil, in the pretreatment.

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