It has been known that dioxin-like polychlorinated biphenyl (DL-PCB) is present in almost all types of environments worldwide. Adsorption treatment of DL-PCB has been expected for one of the simple and low-cost removal technology. In the present study, DL-PCB adsorption capability of bamboo powder charcoal and activated carbon were investigated. Bamboo charcoal and activated carbon were prepared by carbonization and activation with air, carbon dioxide, and steam. The pore properties of obtained adsorbents were analyzed by the Brunauer-Emmett-Teller (BET) for surface area, t-plot analysis for micropore, and the Barrett-Joyner- Halenda (BJH) method for mesopore. Then, adsorption experiments using DL-PCB in hexane solution were conducted. These experiments revealed that every charcoal samples did not show high DL-PCB adsorption activity. On the other hand, activated carbon samples prepared by air and carbon dioxide activation having area of over 1000 m²/g and micropores with diameters of about 0．7 nm exhibited high activity for the adsorption of DL-PCB.

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At Tateyama Murodo (altitude : 2,450m) and Tateyama Gondola (altitude : 1,180m) in Mt. Tateyama area, 30 components of VOCs were measured from the beginning of May to the end of October 2010.
Most of 30 VOCs components were detected. Benzene, toluene, and ethyl benzene showed relatively higher average values.
Acording to the results of back trajectory analysis, air parcels transported from the East Asia occupied about 67% at Tateyama Murodo and about 42% at Tateyama Gondola. It was proved that both points showed a clear environment than the urban area since the average value of all VOCs at both points were lower than those at urban areas.
We have compared the concentrations at both measuring points with the background data in the four directions at Cape Hedo in Okinawa. Although the concentrations of toluene at both points were almost equivalent or slightly lower than the background data in the four directions, the others were almost equivalent or slightly higher than the background data.
Benzene/toluene ratios of the East Asia source at Tateyama Murodo were proved to be extremely higher than those of the other sources. The benzene/toluene ratio is considered to be used for the judgment of contribution of the East Asia source.

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Hexabromocyclododecanes (HBCDs), widely used as additive brominated flame retardants, were determined in muscle of crucian carp (Carassius auratus (gibelio) langsdorfii) taken from 14 freshwater areas throughout Japan during 2003-2005; these sampling sites comprised 10 rivers and 4 ponds and were categorized into 4 groups based on local circumstances; large cities, small cities, agricultural areas and remote areas. HBCDs were detected in all samples analyzed, and total HBCDs ranged from 0.068 to 150 (average: 12, median: 0.37) ng/g wet wt. and 5.0 to 15000 (average: 1200, median: 29) ng/g lipid wt. The higher levels of HBCDs were found in urban areas. α -HBCD was the predominant isomer of HBCDs except for 5 rivers in urban areas where γ -HBCD was abundant. Minor isomers of technical HBCD, δ - and ε -HBCD were not found. To estimate maternal transfer rates of HBCDs, samples (male and female) were taken at the Murasaki River in the spawning season and analyzed their muscles and eggs. Maternal transfer rates of α -, β - and γ -HBCD were 11, 20 and 14%, respectively, which were slightly lower than those of dioxins and organochlorine pesticides.

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In environmental analysis, the commercial reagent and reference material products of analyte compounds are indispensable for chromatography such as GC/MS and LC/MS. However, most of their purities are not certificated traceability to the International System of Units (SI). Hence the possibility that their obscure purities greatly ruin the reliability of the quantitative value is incontrovertible. In this study, the purities of forty one commercial pesticide reagent products (new or old) were determined by a quantitative analytical method which is traceable to SI using nuclear magnetic resonance (qNMR). qNMR is a rapid and simple quantitative analysis method and no reference compound of analyte is needed. The purities of ten commercial reagent products among our measured forty one products are different more than 5% to their labeled purities by the manufacturers, and the values were found in 47.9-94.8%. Therefore it consequently seems that the differences between SI traceable purities and labeled purities cause the error of 5.1-50.8% to the quantitative values of analytes. This result represents that qNMR analysis has potential to work as a bridge of SI traceability and the quality control of reagent product using qNMR is greatly important to secure the accuracy of analytical data.

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