A liquid chromatography tandem-mass spectrometry (LC/MS/MS) method has been developed for highly sensitive determination of diethylstilbestrol (DES) in water.
Two grams of ascorbic acid and five nano grams of diethylstilbestrol-d8 as the surrogate were added to every 2000 mL of water sample. The sample was filtrated with glass fiber filter (GS25) and adjusted to pH2.5 with 6 mol/L of HCl followed by solid phase extraction with a cyclohexyl silica cartridge (InertSep CH). The fraction eluted with 5 mL of methanol was passed through a multilayer solid phase extraction cartridge (GC/SAX/PSA) to remove matrices. The analyte was eluted from the cartridge with 12 mL of methanol. The elute was concentrated to volume approximately 0.25 mL in a test tube at 40°C in water bath under nitrogen gentle stream, and then it was filled up to 0.5 mL with pure water for LC/MS/MS measurement.
Negative electrospray ionization (ESI-negative) was used to ionize diethylstilbestrol and the internal standard (i.e. diethylstilbestrol-d8). The determination was performed by the selected.reaction-monitoring (SRM) method using precursor/ product ion transition m/z 267.45 to 237.41 for diethylstilbestrol and m/z 275.43 to 245.47 for diethylstilbestrol-d8.
The method detection limit (MDL) and the method quantification limit (MQL) are 0.005 ng/L and 0.013 ng/L, respectively. The average recoveries (n =5) from river water and sea water spiked with 0.5 ng of diethylstilbestrol are 104% (RSD 4.0%) and 106% (RSD 2.9%), respectively.
In all the river waters and sea waters sampled in Nagoya city, the concentrations of diethylstilbestrol were below the MDL.

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In recent years, adverse effects on the environment caused by the tire rubber additives listed up as PRTR chemicals has become a great concern. Therefore, it is important to evaluate the fate and behavior of these chemicals in the environment. In this study, the effects of analytical conditions on the stability and extraction recoveries of them in the environmental samples were investigated to establish simultaneous analytical methods of these compounds.
Four hour ultrasonic extraction bellow 40°C was found effective to extract the tire rubber additives from tire rubber particles. Tire rubber additives contained in the atmosphere particles were stable after 4days aeration, their recovery rates were over 87%. Dehydration of solid phase cartridges for the analysis of water samples by centrifuge was more effective than N₂ gas purge method. In order to obtain sufficient recovery rates, water samples should be adjusted at pH6∼8, preserved in cool and dark place and extracted on the sampling day. Both the recovery rates of tire rubber additives in pure and river water were over 85%. Clean up with Florisil cartridge was necessary for the analysis of these chemicals in sediments by LC/MS/MS to get high peak intensity. The recovery rates of tire rubber additives in sediments were over 91%.

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The effects of surface properties of activated carbon (AC), pH and temperature of solution on Cr(VI) removal and reduction were investigated. AC oxidized by HNO₃ could possess large amount of surface functional groups and showed a higher Cr(VI) removal than AC with little amount of surface functional groups prepared by outgassing at 1000°C under neutral conditions. This result indicates that AC possessing the acidic functional groups had a reduction ability of Cr(VI). In contrast, under highly acidic conditions Cr(VI) was more easily reduced to Cr(III). The decrease amount of both adsorbents consequently showed the same value. The decrease amount increased with the increase in temperature. From the difference in reduction amount of Cr(VI) on AC which had different surface conditions, the carboxylic and/or carboxylate groups would be involved in the reduction process.

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Naphthalene is the most abundant polycyclic aromatic hydrocarbon for environmental exposure of humans and its carcinogenicity in rodents was recently demonstrated. Naphthalene concentrations in indoor and outdoor air of 30 residences of general public living in Metropolitan Tokyo and Hyogo Prefecture were measured. Median concentrations of naphthalene in indoor air was 0.37 (range: 0.15 to 58) and 0.43 (0.16-19) μg/m³ for living room (n=30) and bed room (n=18), respectively, with a great residence-to-residence variability. They were higher than the concentration in outdoor air (median: 0.16 μg/m³). Indoor to outdoor ratio (I/O) of naphthalene concentration ranged from 0.4 to 275: it was >1.0 for 26 out of 30 residences. This indicated that indoor source(s) of naphthalene is present in most of the residences. Since lifetime cancer risk posed by inhalation of naphthalene in indoor and outdoor airs at the present level was calculated to be >10⁵, risk reduction was desirable. Elevated concentration of indoor naphthalene was found after cooking in five residences indicating that cooking can be one of the common sources of naphthalene across residences. Investigation of two residences with greater I/O revealed that repellent can be a significant source of indoor naphthalene.

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The concentration of Cu and Zn in the compost produced from Horse dung (HDC) was 10.4 and 108 mg kg ^-1. The concentration of Cu and Zn in the compost produced from Swine manure (SMC) was 183 and 670 mg kg ^-1. Moreover, Cu was mainly collected into a fraction of Organic-complexes, and Zn into a fraction of Iron and manganese oxide.
For cultivation experiments, HDC and SMC was mixed with polytetrafluoroethylene (TF) powder and used as a medium for Peas (Pisum sativam L.). Cu in HDC-TF medium and SMC-TF medium mainly existed as Organic-complexes form. Additionally, Zn in these mediums mainly existed as Carbonate and Iron and manganese oxide forms. It was considered that Cu and Zn in Organic-complexes form were gradually transferred to a water-soluble fraction which is bioavailable according to cultivation time. Finally, it is supposed that the fraction of Organic-complexes form played as a storage (so called “Sink”) of Cu and Zn.

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The occurrence and ubiquitous distribution of persistent emerging pollutants, benzotriazole UV stabilizers (BUVSs), have been reported in the environment. However, little information is available on their potential sources of environmental exposure to BUVSs. In this study, we analyzed four BUVSs, such as UV-320, UV-326, UV-327, and UV-328, in road dust samples collected from Route 3 in Kumamoto Prefecture. BUVSs were detected in most samples analyzed, at geometric mean concentrations of 0.61, 11, 3.3, and 12 ng/g dry wt. for UV-320, UV-326, UV-327, and UV-328, respectively. Significant correlations were found between BUVSs concentrations in road dusts and traffic density, suggesting that automobile was a major source of BUVSs in road dust. The amounts of BUVSs on the surface of the Route 3 in Kumamoto city was estimated as 1,700 μg, and a samples of 60 ∼ 250 μm particles was the dominant fraction to accumulate BUVSs in road dust. These results indicates that road dust may be a non-point source of BUVSs into the environment.

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Total and inorganic arsenic (tAs and iAs) analysis of soils and house dust samples, collected pair-wise from 41 residences of general public in Japan, was carried out to estimate contributions of these non-dietary oral sources to total daily exposure level of iAs, an established human carcinogen. Total As concentration in the samples was determined after mixed acid digestion followed by ICP mass spectrometric (ICPMS) determination. Non-spectroscopic interference arising from residual carbon in the digest was successfully compensated by addition of 3% acetic acid to sample digest and standard solution. Concentration of iAs in soil and house dust samples (n=20 each) was measured by liquid chromatography- ICPMS after extraction with synthetic gastric juice. Median tAs concentration in soil (n=38) and house dust (n=40) was 10 and 2.5 mg/kg, respectively. Median iAs (AsIII+AsV) concentration was <0.01 and 0.24 mg/kg, respectively. Assuming that adult unintentionally ingest 50 mg each of soil and house dust, daily exposure level was estimated to be 0.0005 and 0.012 μg/day, respectively. When recently reported daily dietary iAs intake (mean of two estimates: 15.4 μg/day) is considered, contributions from soil and house dust to total daily oral exposure was estimated to be 0.003 and 0.08%, respectively. Soil and house dust ingestion, as well as inhalation exposure (estimated to be 0.02 μg/day), was found to be insignificant for total daily iAs exposure of Japanese.

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The degradation of 4-chloro-4′-hydroxybiphenyl (4-CHBP), as a model compound of polychlorinated biphenyls, was studied in aqueous solution using advanced oxidation processes (O₃/TiO₂ and O₃/TiO₂/H₂O₂ systems). TiO₂ was immobilized by a dip-coating method on the external surface of several glass sheets. The effects of operating variables, including the initial concentrations of ozone and hydrogen peroxide and solution pH, on the degradation rates of 4-CHBP and total organic carbon (TOC) were investigated. In the O₃/TiO₂/H₂O₂ system, the effect of varying the mass ratio of hydrogen peroxide to ozone from 0 to 4 (w/w) on the degradation rates of 4-CHBP and TOC was also determined. The degradation of 4-CHBP and TOC increased as a function of ozone concentration in ozonation. Furthermore, the degradation of 4-CHBP was also enhanced by increasing the pH in the O₃/TiO₂ and O₃/TiO₂/H₂O₂ systems. Hydrogen peroxide initially enhanced 4-CHBP and TOC degradation in aqueous solution. However, further increases in the H₂O₂:O₃ mass ratio above 1 (w/w) in the O₃/TiO₂/H₂O₂ system negatively affected the degradative action of H₂O₂ and led to a decrease in 4-CHBP and TOC degradation.

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In this study, an analytical method for perfluorinated compounds (PFCs) in granular activated carbon (GAC) was investigated. The investigation of analysis was conducted by using GAC which adsorbed PFCs from artificial waste water containing PFCs of known amount. As results, it was confirmed that Accelerated solvent extraction (ASE) method using acetone as the solvent was appropriate for the extraction of PFCs in GAC.
PFCs in used GAC samples, regenerated GAC samples, and a new GAC sample were analyzed by using the investigated method. The concentration of PFCs in the regenerated GAC was decreased by more than 99.9% compared with the used one. PFCs in GAC may transform and/or desorb at regeneration processes.

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