Phosphate fertilizer is thought to be the major source of F input in agricultural soils. We consider that F accumulation in Japanese agricultural soil is caused by excessive application of phosphate fertilizer, because Japan is one of the major chemical fertilizer consumer nations in the world. In this study, we analyzed the F concentration in greenhouse soils sampled from farms in southern Kyushu, Japan, and investigated the possibility of the F accumulation in the soils by comparing the concentrations in the greenhouse soils with those in neighboring non-cultivated soils. The total F concentration in non-cultivated soils and greenhouse soils ranged from 53 to 248 mg/kg and from 163 to 471 mg/kg, respectively. Almost all greenhouse soils had a higher total F concentration than the neighboring non-cultivated soils, which indicates that total F concentrations were generally higher in almost all greenhouse soils. The water-soluble F concentrations in non-cultivated soils and greenhouse soils ranged from 0.15 to 4.89 mg/kg and from 1.75 to 20.3 mg/kg, respectively. As well as total F concentration, almost all greenhouse soils had a higher water-soluble F concentration than the neighboring non-cultivated soils. A positive correlation was observed between the total F and the total P concentrations in greenhouse soils, which indicates that the F in the greenhouse soils is derived from phosphate fertilizers. The above results indicate that soil F accumulation is due to excessive application of phosphate fertilizers that are widely used on greenhouse soils throughout Japan, and water-soluble F concentrations are correspondingly elevated in these soils.

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The contamination levels of bisphenol A (BPA) and tetrabromobisphenol A (TeBBPA) were determined in breast milk samples from seventeen Japanese mothers. BPA and TeBBPA were detected in most samples in the ranges of 1.4 –380 ng/g lipid (n ＝17, mean: 35 ng/g lipid) and n.d. – 8.7 ng/g lipid (n ＝17, mean: 2.0 ng/g lipid), respectively. Subsequently, we also observed an extremely interesting unknown peak in the samples, and this peak was identified as tribromobisphenol A (TriBBPA). Then, when we reanalyzed the samples, TriBBPA was also detected in most samples (mean: 6.0 ng/g lipid). The average concentration of TriBBPA was 3.0 times higher than that of TeBBPA. In addition, we investigated time-dependent changes for 24 hr in breast milk of two donors.It was estimated that higher levels of TriBBPA represent a debrominated metabolite of TeBBPA which has been ingested via food. Based on levels of the breast milk, we calculated and compared the daily intake of TeBBPA and TriBBPA for infants through breast milk. The intake of TriBBPA was about 4 times higher than that of TeBBPA.
Further study is needed to clarify the contamination level of not only TeBBPA but also its metabolites in the human, especially infants, and their detailed mechanism of toxicity.

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Mesoporous activated carbons were prepared from three types of bamboo materials, i.e. non-pretreated, acid-pretreated and base-pretreated bamboos, by H₃PO₄ and ZnCl₂ activation. Acid- and base-pretreatments of bamboo materials were performed using H₂SO₄ and NaOH, respectively, in order to alter bamboo components and enhance an activation effect. The change in bamboo components by acid- or base-pretreatment was examined by thermogravimetric analysis. The porous structure of prepared activated carbons was also characterized through N₂ adsorption-desorption isotherms at －196℃. The results showed that the base-pretreatment of raw materials had the positive effect on mesopore development during H₃PO₄ and ZnCl₂ activation processes, while such kind of effect by acid-pretreatment was observed only for ZnCl₂ activation. The most mesoporous sample prepared from base-pretreated bamboo by H₃PO₄ activation with the impregnation ratio of 6 g/g showed the S_BET, V_meso and D_ave values of 1380 m²/g, 1.54 cm³/g and 6.0 nm, respectively. The dye adsorption experiments were carried out through a batch test to evaluate each prepared activated carbon. Methylene blue and direct blue 71 were chosen as adsorbates. ZnCl₂ activated carbons had the better adsorption capacity for methylene blue compared to H₃PO₄ activated carbons, which were not well-suited for the methylene blue adsorption probably due to their smaller S_BET and positive charge on surface. The most mesoporous sample had the largest amount of direct blue 71 adsorption (0.97 mmol/g) among the all samples, suggesting that the prepared mesoporous activated carbons would be a valuable material for the removal of bulky dyes.

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Methods for measuring hair dye ingredients in urine, shampoo-water mixture, and river water were developed using solid phase extraction (SPE) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Coloring of hair results in the deposition of aromatic amine constituents on the hair and scalp, a portion of which passes through the skin, accumulating in the human body or being excreted. Ingredients in hair dye have been implicated in many kinds of adverse effects in humans, for example, dermatitis, allergies, and cancer. For purposes of this study, we checked for aromatic amines routinely present in hair dyes, and selected three target chemicals that are the most frequently used, namely, 2-methyl-5-aminophenol, 2,5-diaminotoluene, and 4-aminophenol. These amines are extremely water soluble and highly susceptible to oxidation. In the case of river water analysis, fifty milliliters of the sample with added ascorbic acid, as the antioxidant, was passed through an ion exchange cartridge. In the analysis of shampoo-water mixture, ten milliliters of the sample diluted nineteen fold with 1% ascorbic acid was passed through the ion exchange cartridge. In the case of urine, the sample containing ascorbic acid was diluted with a mixture of methanol and 2-propanol followed by centrifugation, and the supernatant was filtered.
Before concentrating the eluted samples under a stream of nitrogen, acetonitrile was added as a keeper solvent to the solution eluted from the SPE cartridge, and the temperature of the solution was maintained below 37 ℃ to prevent the evaporation and oxidation of the target chemicals. The recoveries of the target chemicals were 96.5 ～123.8% (RSD 3.8 ～12.8%) for river water, 75.8 ～129.0% (RSD 3.3 ～8.3%) for shampoo-water mixture, and 75.8 ～127% (RSD 7.7 ～14.8%) for urine.

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To prevent groundwater pollution with NO₃^－ from fertilizer and manure used in tea field, we evaluated the performance of anion exchange resins A-D by examining whether they adsorb NO₃^－ in soil water from tea field using a soil column test. Anion exchange resin A, which gave the best results, was selected for the soil column test. Low concentrations of NO₃^－ and SO₄^2－ were detected in eluates when 185 mL of NO₃^－ aqueous solution was passed through a column packed with 30 g of soil from tea field and 10 g of anion exchange resin A. Similarly, low concentrations of NO₃^－ and SO₄^2－ were detected in eluates when 185 mL of spring water from a catchment area of tea field was passed through a column.

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Although each step in the quantitative analysis of trace substances is susceptible to marked variability, it is assumed that there is only a negligible difference in the quality of concentration tubes, and that the concentration step, which is performed in such tubes under a nitrogen gas stream to obtain the desired volume, generates very few sources of variation. Therefore, using a quantitative method for measuring benzo(a)pyrene (B(a)P) as a test procedure, we estimated uncertainties involved in each step, from sampling to instrumental analysis, and evaluated the effect of concentration tubes on the measurement accuracy based on an uncertainty analysis. As the results, the combined relative standard uncertainty for the determination of 1.0 mg/L of (B(a)P) was 3.3-5.4%, of which the contribution of concentration tubes was 67.3-87.8%. The present study demonstrated that uncertainty on use of concentration tubes affects measurement accuracy, and highlighted the need to introduce precision control in vessel use.

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A highly sensitive method for the quantification of poly(oxyethylene)octylphenyl ether homologues (OPEs, where OPEn is an OPE homologue with n ethoxy units), which are nonionic surfactants, in environmental water has been developed using solid phase extraction (SPE) and liquid chromatography tandem-mass spectrometry (LC/MS/MS).
Methanol was added to environmental water samples as a preservative in 10% v/v concentration. The water samples were passed through a preconditioned SPE cartridge (EDS-1) to collect the OPEs, which were then eluted from the cartridge using a mixed solvent of methanol and ethyl acetate (1:1, v/v). The eluate was concentrated and dissolved in a mixed solvent of methanol and deionized water (Milli-Q) (1:1, v/v). The OPEs in the prepared solutions were then analyzed by LS/MS/MS.
The method detection limits (MDLs) for the detection of OPEs range from 0.17 ng/L for OPE5, to 2.0 ng/L for OPE1. The MDL of total OPEs is 6.1 ng/L, which was obtained by adding all the individual MDL values. The method quantification limits (MQLs) for quantification of OPEs range from 0.42 ng/L for OPE5, to 5.2 ng/L for OPE1. The MQL of total OPEs is 17 ng/L. The average recovery of OPEs in water samples ranged from 78% to 100% (c.v. 1.2-10%). The MQL of total OPEs was below the predicted "no effect" concentration used by the Ministry of the Environment, Government of Japan, for the initial assessment of ecological risk. In samples from Hokkaido, the OPEs in seawater were below the MQL and those in river water below the MDL when using this method.

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