Publications by authors named "Sokichi Takagi"

In order to protect human health and the environment, highly efficient, low-cost, labor-saving, and green analysis of toxic chemicals are urgently required. To achieve this objective, we have developed a novel database-based automated identification and quantification system (AIQS) using LC-QTOF-MS. Since the AIQS uses retention times (RTs), exact MS and MS-MS spectra, and calibration curves of 484 chemicals registered in the database instead of the use of standards, the targets can be determined with low-cost in a short time.

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Benzotriazole ultraviolet stabilizers (BUVSs) used in consumer products are raising concerns as new pollutants in the aquatic environment. We determined the agonistic activities of eight BUVSs and a chemically distinct UV absorber (4-methylbenzylidinecamphor) toward the human aryl hydrocarbon receptor (AhR) and thyroid hormone receptors alpha and beta. Although none of the BUVSs showed ligand activity against the thyroid hormone receptors, four of them (UV-P, UV-9, UV-326, and UV-090) showed significant AhR ligand activity.

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This study estimated daily exposure to Dechlorane Plus (DP) and polybrominated diphenyl ethers (PBDE) via inhalation and diet. Samples of atmospheric particles and food (obtained by market basket method) from Osaka, Japan were analyzed for DP (syn-, anti-) and PBDE using gas chromatography-mass spectrometry. DP was detected in both atmospheric particles and food samples.

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Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) have been recognized as global environmental pollutants. Although PFOS and PFOA have been detected in tap water from Japan and several other countries, very few studies have examined the fate, especially removal, of perfluorinated compounds (PFCs) in drinking water treatment processes. In this study, we analyzed PFOS and PFOA at every stages of drinking water treatment processes in several water purification plants that employ advanced water treatment technologies.

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Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) have been recognized as emerging environmental pollutants because of their ubiquitous occurrence in the environment, biota, and humans. PFOS and PFOA have been detected in water in Japan. Nevertheless, occurrence of PFOS and PFOA in potable water from municipal water treatment plants is not clearly known.

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Perfluorooctanoate (PFOA) are environmental contaminants posing special public health concerns because of their long-term persistence and bioaccumulation in the environment. Fluorotelomer alcohols are volatile and may undergo long-range transport. Air samples were collected at five sites in the Keihan area, Japan: Sakyo, Morinomiya and three sites in Higashiyodogawa.

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Many methods for the determination of pesticide residues in food have been reported. Although natural medicines should be confirmed to be as safe as food, few methods for the determination of pesticide residues in natural medicines have been reported. In this study, 17 organochlorine pesticides were detected in natural medicines using GC/MS with negative chemical ionization (NCI).

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