Quantitative analysis of Sb and Ge contained in PET bottles and their recycled products were performed by microwave assisted acid digestion/ICP-AES. This test method was considered to be useful, because the analytical value of certified materials were corresponded to the certified value. Sb or Ge which used as a polymerization catalyst was remained in PET bottles, and the content of Sb were 128∼198 μg/g (11/21), and the content of Ge were 28∼50 μg/g (10/21), respectively. On the other hand, analytical results of their recycled materials and final products showed that the content of Sb in some cases, for example; a textile goods, a bottle for detergent and a pack of fruits, were high as same as PET bottles. We assumed that new Sb may be added in the new materials blended in the recycling materials.

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Charcoal was prepared from polyvinyl chloride resin (PVC) containing calcium carbonate in inert nitrogen flow at temperature ranging 500∼900 °C to examine the humidity control ability using adsorption isotherms of moisture. Prepared charcoal showed excellent humidity control ability due to calcium chloride formed during the carbonization. Conducting the humidity control experiments after boiled water washing, 700 °C carbonized charcoal exhibited superior humidity control to 500 °C charcoal. Calcium carbonate in the PVC is considered to be converted to calcium oxide at 700 °C, followed by forming calcium hydroxide by boiled water washing. Porous charcoal prepared with altering gases between air and nitrogen and heating pattern also revealed good humidity control compared to non-porous charcoal.

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The evolved gaseous samples from several metal halide particles upon heating at temperatures ranging from 200 to 500°C in a laboratory quarts tube reactor under dry air stream were analyzed to compare their potentials of active halogen formation. Total yields of the active halogen evolved were found to be one mole Cl per mole CuCl₂ and two moles Br per mole CuBr₂ at 300 °C for 30 min. A small amount of the active chlorine was detected when FeCl₃ was heated under the same conditions. However, FeCl₂, SnCl₂, SnCl₄, ZnCl₂ and ZnBr₂ did not produced the active halogen upon heating at temperature ranging 200 to 500°C for 60 min.
The efficiency of DD and DF halogenation by CuCl₂ or CuBr₂, and the distribution of halogenated DD/DF products were also measured using the tube reactor under the same pyrolysis conditions. At the gas velocity, corresponding to a resident time of 0.5 s in the reactor, monohalogenated DD/DF yields were largest, with yields decreasing with increasing DD/DF halogenation. The DD/DF halogenations were strongly favored at lateral sites, with the predominant halogenated DD/DF isomers within each homologue group those containing halogen substituents at only the 2,3,7,8 positions.

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Continuous sampling of dioxins in ambient air was carried out using a low-volume air sampler at the southeast site in Tokyo during a period of FY 2000 to FY 2004. The temporal trend of toxic equivalency quantity (TEQ) was evaluated the relation with Tokyo's inventory which was estimated to be almost completely emitted from combustion sources. The annual average of TEQ was observed to have a more similar tendency to a variation in the inventory than that of regular monitoring with a short term sampling. However, the reduction rate of TEQ for 5 years was less than that of the inventory. Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) increased from late autumn to winter, whereas those of coplanar polychlorinated biphenyls (Co-PCBs) elevated in summer and the seasonal variation seemed to be dependent on temperature. As PCB products and combustion were known to be the major sources of Co-PCBs, we have attempted to estimate the source contribution rates using the method of Bayesian chemical mass balance. Though Co-PCBs derived from PCB products were extrapolated a significant contributor at total concentration base, Co-PCBs emitted from combustion seemed to constitute over 90 % based on TEQ as consequence of higher toxic equivalency factor of their isomers.

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In this study, in order to elucidate benzene decomposition reaction path on V₂O₅ catalysis, ab initio molecular orbital calculation has been conducted for 5 elemental reaction steps involved in the reaction between benzene and V₂O₉H₈ cluster, proposed by Jaine, et al., i.e. benzene adsorption, hydrogen atom surface transfer, hydrogen gas de-sorption, oxygen gas adsorption and benzene ring decomposition. Molecular structures in stable state, transition state and intermediate molecular structures have been revealed in this proposed reaction steps. The reaction scheme can be described as follows; (1) electron in benzene transfer themselves to the catalysis cluster, whereby hydrogen atom transfer on the catalysis surface proceeds for the subsequent hydrogen molecular gas de-sorption, and (2) benzene ring decomposition takes place via the unique Mars-van Krevelen mechanism on V₂O₅ catalysis.

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Large-volume sample injection technique was utilized for gas chromatography-mass spectrometric determination of ergosterol to estimate fungal biomass of indoor and outdoor air. Sample was collected with a low volume air sampler onto a filer paper for 24 hours and saponified in methanolic KOH. Ergosterol was extracted with n-hexane and then derivatized to its TMS ether. The ergosterol-TMS ether was stable for a month in a refrigerator.
The measurements of ergosterol in the samples were carried out by sample injection of 50 μl using a large volume injector into GC/MS followed by SIM analysis using ions m/z 363, 337 and 468. The lowest detectable amounts of the TMS derivative of ergosterol was 5 pg (signal-to-noise ratio of 3, m/z 363).
Actual air samples had been collected monthly in Nara city from January to December throughout 2006. The samples of indoor and outdoor air contained ergosterol from 0.03 to 0.96 ng/m³ and from 0.04 to 0.49 ng/m³, respectively.

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A simple pre-concentration method of dalapon (2,2-dichloropropionic acid) in water for LC/MS analysis by two-step liquid-liquid extraction is proposed. Dalapon was extracted from 200 ml of water sample containing 2 ml of sulfuric acid and 80 g of sodium chloride into 10 ml of methyl-t-butyl ether (MTBE). Then, dalapon was back-extracted from 5 ml portion of the MTBE extract into 1 ml of aqueous solution (water, several concentrations of sodium hydroxide solution or phosphate buffer solution). An aliquot of the aqueous phase was directly injected to LC/MS apparatus. Recovery of dalapon depended on equilibrium pH after the second step extraction. The best recovery was observed in the pH range from 6 to 8. When the phosphate buffer solution (pH 6.87) was used as the aqueous phase in the second step extraction, no change in the pH value of the aqueous phase was observed between before and after extraction. Therefore, phosphate buffer solution was suitable for the second step extraction.
The recovery of dalapon (0.0008 mg/l) by the proposed method was about 120 % and the relative standard deviation of five replicate runs was below 3 %. This method is satisfactorily applicable to LC/MS analysis of detection limit of dalapon (0.0008 mg/l) in tap water provided by the Ministry of Health Labour and Welfare of Japan.

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The present paper describes the soil surveys of lead contamination at the clay target shooting range and around of the industrial waste incinerator located in Saitama Prefecture. In these surveys, lead leachabilities of soil samples without contamination frequently exceeded environmental quality standard (0.01mg/l) normalized in soil contamination countermeasures low. Lead leachabilities closely related to the soil type in the contaminated areas and exceedances of environmental quality standard of lead were mainly observed in the case of non-volcanic ash soils. In the case of volcanic ash soils, on the other hand, lead leachabilities did not exceed environmental quality standard at all, even at lead contents in soils more than 150mg/kg. Leads in the leached solution were present as colloid with organic-inorganic composites that were consisted of humic substances and clay particles. Parts of these soil colloids which were very fine particles were easily dispersed in the liquid phase during soil leaching test and any of them could not be captured by a 0.45 μm membrane filter. Lead colloids hardly permeated through the soil column and had little possibility of diffusion to the groundwater. For a correct estimation of lead contamination based on soil leaching test, an examination of the soil properties at the field and appearances of the leached solution obtained is extremely important as well as analytical results.

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