Directory of Researchers

OKAMURA Hideo
Research Center for Inland Seas
Professor
Other Natural Science Field
Last Updated :2020/08/05

Researcher Profile and Settings

Affiliation

  • <Faculty / Graduate School / Others>

    Research Center for Inland Seas
  • <Related Faculty / Graduate School / Others>

    Faculty of Maritime Sciences / Department of Ocean Safety Systems Sciences, Graduate School of Maritime Sciences / Department of Maritime Sciences, Graduate School of Maritime Sciences / International Maritime Research Center

Teaching

  • Faculty of Maritime Sciences, 2019, Coastal Oceanography
  • Faculty of Maritime Sciences, 2019, Basic Experiments of Maritime Science 2
  • Faculty of Maritime Sciences, 2019, Basic Experiments of Maritime Science 2
  • Faculty of Maritime Sciences, 2019, Experiments in Marine Science and Technology
  • Faculty of Maritime Sciences, 2019, Experiments in Marine Science and Technology 1
  • Faculty of Maritime Sciences, 2019, Introduction to Marine Science and Technology
  • Faculty of Maritime Sciences, 2019, Introduction to Marine Science and Technology
  • Faculty of Maritime Sciences, 2019, Environmental Science for Inland Seas
  • Faculty of Maritime Sciences, 2019, Environmental Science for Inland Seas 1
  • Faculty of Maritime Sciences, 2019, Environmental Science for Inland Seas 2
  • Graduate School of Maritime Sciences / Department of Maritime Sciences, 2019, Aquatic Environmental Science2
  • Graduate School of Maritime Sciences / Department of Maritime Sciences, 2019, Advanced Aquatic Environmental Science1

Research Activities

Research Interests

  • antifouling compounds
  • marine environment
  • biocides
  • chemicals
  • environmental assessment

Research Areas

  • Environmental science/Agricultural science / Environmental dynamics
  • Environmental science/Agricultural science / Environmental impact assessment

Published Papers

  • ディーゼル機関からのススの変異原性と多環芳香族炭化水素の関係

    Kento Hayami, Akira Yoshida, Masashi Kusu, Go-ichi Kon, Hideo Okamura, Tomohisa Dan, Yoshinori Haga, Ryohei Nakatsubo, Senri Matsumura

    The Japan Institute of Marine Engineering, Oct. 2019, Proceedings of 89th Marine Engineering Conference, Japanese

    Symposium

  • Evaluation of Bio-Gasoline Combustion in Outboard Spark Ignition Engine

    Wataru Miyazaki, Toru Hayakawa, Kodai Nakano, Ichiro Asano, Hideo Okamura, Tomohisa Dan

    The Society of Naval Architects of Korea (SNAK), Oct. 2018, 8th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2018 (Busan), pp.597 - 601, English

    [Refereed]

    International conference proceedings

  • Analysis of Organic Contamination in Ship Engine Soot

    Senri Matsumura, Yoshinori Haga, Ryosuke Yoshiori, Ryohei Nakatsubo, Go-ichi Kon, Hideo Okamura, Tomohisa Dan, Toshiki Tojo, Hitomi Hasegawa, Takashi Miyawaki, Takahiro Nishino, Takeshi Nakano

    Japan Society on Water Environment, Sep. 2018, Proceedings of 21st Symposium of JSWE (Shimane), pp.157, Japanese

    Symposium

  • Vesna Lavtizar, Daisuke Kimura, Satoshi Asaoka, Hideo Okamura

    Copper pyrithione (CuPT) is a biocide, used worldwide to prevent biofouling on submerged surfaces. In aquatic environments it rapidly degrades, however, one of the degradation products (HPT) is known to react with cupric ion back to its parent compound. Not much is known about the behavior and toxicity of CuPT and its degradation product HPT in different water systems. Hence, our aim was to investigate the ecotoxicity of CuPT, HPT as well as Cu2+ to the brine shrimp Artemia salina in natural seawater and organic matter-free artificial seawater. Moreover, in order to elucidate the influence of ionic strength of water on CuPT toxicity, tests were performed in water media with modified salinity. The results showed that CuPT was the most toxic to the exposed crustaceans in a seawater media with the highest salinity and with no organic matter content. HPT in a presence of cupric ion converted to CuPT, but the measured CuPT concentrations and the mortality of A. salina in natural water were lower than in artificial water. The toxicity of CuPT to A. salina was significantly influenced by the organic matter content, salinity, and proportions of constituent salts in water. In a combination with cupric ion, non-hazardous degradation product HPT exhibits increased toxicity due to its rapid transformation to its parent compound.

    ACADEMIC PRESS INC ELSEVIER SCIENCE, Jan. 2018, ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY, 147, 132 - 138, English

    [Refereed]

    Scientific journal

  • 日本で使用される防汚システムの現状(2018)

    三重野紘央, OKAMURA HIDEO, 勝井辰博, 沖本洋幸

    2018, 神戸大学海事科学部紀要, 15, 77 - 88, Japanese

    Research institution

  • Evaluation of Bio-gasoline Combustion in Outboard Spark Ignition Engine

    Toru Hayakawa, Wataru Miyazaki, Hideo Okamura, Ichiro Asano, Tomohisa Dan

    In present days, ethanol mixed gasoline, so called bio-gasoline, is used as an alternative fuel in spark ignition engines. Especially, it is more used in the prime mover for the land in order to suppress the global warming and the air pollution, and establish as a sustainable energy resource. Outboard engine is a compact propulsion device usually used in small size boats. It co

    The Japan Institute of Marine Engineering (JIME), Oct. 2017, The 11th International Symposium on Marine Engineering (ISME2017 TOKYO), (A03-208), pp.213 - 217, English

    International conference proceedings

  • Takanari Hattori, Hideo Okamura, Satoshi Asaoka, Keiichi Fukushi

    Transient isotachophoresis (tITP) with a system-induced terminator (SIT) was developed for capillary zone electrophoresis (CZE) determination of aniline (An(+)) and pyridine (Py+) in sewage samples. After sample injection, a water vial was set at the sample-inlet side. Then voltage was applied to generate a system-induced terminator (H+). Experiments and simulations revealed a concentration effect by tITP with an SIT: background electrolyte (BGE) -100 mM acetic acid (AcOH) and 50 mM NaOH (pH 4.6); detection wavelength -200 nm for An(+) and 254 nm for Py+; vacuum injection period -15 s (190 nL); SIT generation -10 kV applied for 80 s with the sample inlet side anode; separation voltage -20 kV with the sample inlet side anode. The limits of detection (LODs, S/N = 3) of An(+) and Py+ respectively reached 10 and 42 mu g/L, with good repeatability (peak area RSDs <= 6.9%) and calibration graph linearity (R-2 = 0.9997). The proposed method was applied for determination of An(+) and Py+ in sewage samples. Recoveries of An(+) (0.50 mg/L) and Py+ (2.0 mg/L) in spiked sewage samples were 94-104%. (C) 2017 Elsevier B.V. All rights reserved.

    ELSEVIER SCIENCE BV, Aug. 2017, JOURNAL OF CHROMATOGRAPHY A, 1511, 132 - 137, English

    [Refereed]

    Scientific journal

  • Vladimir P. Beskoski, Katsuya Yamamoto, Atsushi Yamamoto, Hideo Okamura, Mitsuru Hayashi, Takeshi Nakano, Chisato Matsumura, Keiichi Fukushi, Shinpei Wada, Hideyuki Inui

    Perfluoroalkyl acids (PFAAs) including perfluoroalkyl sulfonates (PFSAs) and perfluoroallcyl carboxylates (PFCAs) were analyzed in sediment samples taken from Ajifu Waterway in Osaka city, from Osaka Bay, and from Kagoshima Bay, as well as in fifteen seawater samples collected from Osaka Bay and coastal waters of Western Japan. In all sediment samples, only PFCAs were detected, and the highest concentration was determined in Ajifu Waterway, where Sigma PFAA was 58990 ng kg(-1) dry weight. The total concentrations of PFAAs in sea water samples ranged between the limit of quantification and 53.4 ng L-1, and perfluorohexanoic acid was the most prevalent and had the highest concentration of 37 ng L-1. The changes in the patterns and concentrations of PFAA5 in Osaka Bay and coastal waters of Western Japan indicate that the PFAAs in surface waters are influenced by sources from Keihanshin Metropolitan Area, mainly the Yodo River basin, and the dilution effect which naturally occurs during their transport to the Pacific Ocean. (C) 2016 Elsevier Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Mar. 2017, CHEMOSPHERE, 170, 260 - 265, English

    [Refereed]

    Scientific journal

  • Satoshi Asaoka, Hideo Okamura, Kyunghoi Kim, Yuzuru Hatanaka, Kenji Nakamoto, Kazutoshi Hino, Takahito Oikawa, Shinjiro Hayakawa, Tetsuji Okuda

    Reducing hydrogen sulfide concentration in eutrophic marine sediments is crucial to maintaining healthy aquatic ecosystems. Managing fly ash, 750 million tons of which is generated annually throughout the world, is another serious environmental problem. In this study, we develop an approach that addresses both these issues by mixing coal fly ash from coal-fired power plants with blast furnace cement to remediate eutrophic sediments. The purpose of this study is to optimize the mixing ratio of coal fly ash and blast furnace cement to improve the rate of hydrogen sulfide removal based on scientific evidence obtained by removal experiments and XAFS, XRD, BET, and SEM images. In the case of 10 mg-S L-1 of hydrogen sulfide, the highest removal rate of hydrogen sulfide was observed for 87 wt% of coal fly ash due to decreased competition of adsorption between sulfide and hydroxyl ions. Whereas regarding 100 mg-S L-1, the hydrogen sulfide removal rate was the highest for 95 wt% of coal fly ash. However, for both concentrations, the removal rate obtained by 87 wt% and 95 wt% were statistically insignificant. The crushing strength of the mixture was over 1.2 N mm(-2) when the coal fly ash mixing ratio was less than 95 wt%. Consequently, the mixing ratio of coal fly ash was optimized at 87 wt% in terms of achieving both high hydrogen sulfide removal rate and sufficient crushing strength. (C) 2016 Elsevier Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Feb. 2017, CHEMOSPHERE, 168, 384 - 389, English

    [Refereed]

    Scientific journal

  • Satoshi Asaoka, Tamiji Yamamoto, Hironori Yamamoto, Hideo Okamura, Kazutoshi Hino, Kenji Nakamoto, Tadashi Saito

    Hydrogen sulfide generated in eutrophic marine sediment is harmful for living organisms. It is therefore necessary to remove hydrogen sulfide from the sediment to restore benthic ecosystems. Previous studies revealed that granulated coal ash, which is a by-product of coal thermal electric power stations, could remove and oxidize hydrogen sulfide. In this study, we propose a simplified simulation model to estimate the hydrogen sulfide removal efficiency of granulated coal ash. Hydrogen sulfide concentrations in eutrophic marine sediment pore water with and without the application of granulated coal ash were calculated by the proposed model, and the outputs were compared with semi-field or field observation data. The model outputs reproduced the observed data well. Using the proposed model outputs, we suggest an optimum application dosage of granulated coal ash for remediating eutrophic marine sediment. (C) 2015 Elsevier Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, May 2015, MARINE POLLUTION BULLETIN, 94 (1-2), 55 - 61, English

    [Refereed]

    Scientific journal

  • Satoshi Inoue, Yuta Igarashi, Yuko Yoneda, Shingo Kawai, Hideo Okamura, Tomoaki Nishida

    The imidazole fungicide miconazole (MCZ) and the antidepressant sertraline (SER) have the potential to adversely affect aquatic organisms when they are released into the environment. To assess if they could be broken down, MCZ and SER were treated with laccase and manganese peroxidase (MnP) from lignin-degrading white-rot fungi. The MnP-dependent lipid peroxidation system with Tween 80 containing unsaturated fatty acid was effective in eliminating MCZ and SER; the MnP-Tween 80 system helped eliminate 88% of MCZ and 85% of SER after 24 h of treatment. Furthermore, this system eliminated a metabolite of SER (desmethylsertraline or DSER), and no differences between the elimination rates of DSER and SER were observed throughout the treatment period. It was also confirmed that the MnP-Tween 80 system caused a complete loss of growth inhibition by MCZ of the gram-positive bacterium Bacillus subtilis and reduced the growth inhibition by SER of the green alga Pseudokirchneriella sub-capitate by 78% after 24 h of treatment. On the other hand, no appreciable elimination of MCZ and SER was obtained by treatment with laccase, MnP, or the laccase-mediator system with 1-hydroxybenzotriazole. (C) 2015 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, May 2015, INTERNATIONAL BIODETERIORATION & BIODEGRADATION, 100, 79 - 84, English

    [Refereed]

    Scientific journal

  • Satoshi Asaoka, Hideo Okamura, Yusuke Akita, Katsuyoshi Nakano, Kenji Nakamoto, Kazutoshi Hino, Tadashi Saito, Shinjiro Hayakawa, Misaki Katayama, Yasuhiro Inada

    It is important to remove hydrogen sulfide to maintain healthy ecosystems as well as viable aquaculture activities in enclosed water bodies. Granulated coal ash with high adsorption capacity for hydrogen sulfide is a by-product generated from coal combustion processes in coal-fired power plants. The purposes of this study were to (1) verify the regeneration of the adsorption sites for hydrogen sulfide on the granulated coal ash by redox reaction which changes between oxic and anoxic conditions and (2) prove the regeneration mechanisms of the adsorption site which leads to high adsorption capacity for hydrogen sulfide. XAFS analyses of the granulated coal ash revealed that the adsorption site for hydrogen sulfide on the granulated coal ash was regenerated at least 10 times through oxidation of manganese oxide under oxic conditions. A positive correlation (r = 0.995) between the peak top energy of manganese XAFS in the GCA collected from field trial sites and the Eh of the sediments applied with the GCA was observed. These results proved that hydrogen sulfide was adsorbed and oxidized by the granulated coal ash during the stratified season. During the vertical mixing seasons, oxygen regenerates the adsorption site for hydrogen sulfide. It is concluded that this regeneration of adsorption site gives the granulated coal ash high adsorption capacity for hydrogen sulfide. (C) 2014 Elsevier B.V. All rights reserved.

    ELSEVIER SCIENCE SA, Oct. 2014, CHEMICAL ENGINEERING JOURNAL, 254, 531 - 537, English

    [Refereed][Invited]

    Scientific journal

  • Identification of sulfur species adsorbed on particulate matters from ship exhaust gas using XAFS analyses

    Satoshi Asaoka, Hideo Okamura, Tomohisa Dan, Hisayo Okamoto, Shinjiro Hayakawa

    ディーゼルエンジンから排出される粒子状物質(Particulate Matters, PM)にはさまざまな有害物質が含有される。その中で,燃料中の硫黄分は水と反応して硫酸塩(サルフェート)としてPMに吸着されると言われている。本研究では,A重油100%と,A重油にDMEを混合した次世代燃料について,模擬硫黄化合物(DBDS)を添加した場合のPMを解析した。解析は重量法による定量解析と,XAFS(X線)解析を行った。その結果,DME混合によってPM重量が減少すること,PMに含まれる硫黄化合物の分子構造形態を明らかにした。

    Sep. 2014, Proceedings of the 18th Hiroshima International Symposium on Synchrotron Radiation, 18, 151 - 152, English

    [Refereed]

    International conference proceedings

  • Satoshi ASAOKA, Hideo OKAMURA, Ryosuke MORISAWA, Hiroshi MURAKAMI, Keiichi FUKUSHI, Toshihiro OKAJIMA, Misaki KATAYAMA, Yasuhiro INADA, Chihoro YOGI, Toshiaki OHTA

    Jul. 2013, Chemical Engineering Journal, 228, 843 - 849, English

    [Refereed][Invited]

    Scientific journal

  • Togosmaa,L, OKAMURA HIDEO, Satoshi ASAOKA

    Jun. 2013, 環境化学, 23 (2), 65 - 72, Japanese

    [Refereed]

    Scientific journal

  • Hideo Okamura, K. Shoji, Ka. Miyata, H. Sugawara, T. Moriwaki, Y. Ikemoto

    2013, J. Phys. Soc. Jpn., 82 (7), 1 - 74720, English

    [Refereed]

    Scientific journal

  • Tsunemasa,N, Tsuboi,A, OKAMURA HIDEO

    2013, Int.J.Molecular Sci., 14 (1), 421 - 433, English

    [Refereed]

    Scientific journal

  • Ai Tsuboi, Hideo Okamura, Netnapit Kaewchuay, Keiichi Fukushi, Xiaojian Zhou, Tomoaki Nishida

    Triphenylborane-pyridine (TPBP) is an antifouling compound used in Asian countries, including Japan, and its residue has not been detected in aquatic environments to date. There are limited data on its fate for environmental management. The purpose of this study was to evaluate whether TPBP is degraded by metal ions in aquatic environments. TPBP with metal ions in 20mM sodium acetate buffer at pH 8.0 was placed at 25 degrees C in the dark for 24h. The concentrations of TPBP and its degradation products, such as diphenylboronic acid, phenylboronic acid (MPB), phenol, benzene, biphenyl, and boron were determined. The presence of copper ions (50mg/l), but not zinc or manganese ions, resulted in complete degradation of TPBP in 24h. The TPBP degradation was much faster than the boron production in the initial reaction (0-1h) with copper salts, depending on the copper salts tested. TPBP was degraded by copper ions (5mg/l) in 24h, producing phenol, MPB, biphenyl, and borate. Cu2+ as copper(II) chloride or copper(II) acetate led to complete degradation of TPBP, and ethylenediaminetetraacetic acid disodium salt addition suppressed the TPBP degradation. Cu+ as copper(I) acetate also completely degraded TPBP, and bathocuproine addition suppressed the TPBP degradation. This suggests that copper ions existing in natural environments might degrade TPBP released from antifouling paint into water, and this could be one of the important mechanisms to dissipate TPBP residues in aquatic environments.

    TAYLOR & FRANCIS LTD, Oct. 2013, ENVIRONMENTAL TECHNOLOGY, 34 (20), 2839 - 2844, English

    [Refereed]

    Scientific journal

  • Netnapit Kaewchuay, Keiichi Fukushi, Ai Tsuboi, Hideo Okamura, Keiitsu Saito, Takeshi Hirokawa

    We proposed a capillary zone electrophoresis (CZE) procedure using field-amplified sample injection (FASI) for the simultaneous determination of pyridine-triphenylborane (PTPB) and its degradation products: diphenylborinic acid (DPB), phenylboronic acid (MPB), and phenol. The LODs for PTPB, DPB, MPB, and phenol were, respectively, 0.85, 0.88, 44, and 28 mu g L-1. The RSDs (n = 4) for the analytes listed above were in respective ranges of 6.2 - 14, 5.9 - 10, and 0.49 - 0.62% for the peak area, peak height, and migration time. The compounds were extracted from paint-waste samples collected from shipyards using a siliga-gel column. The extract was dissolved with acetonitrile containing 1% (v/v) pyridine. The samples were then analyzed using CZE, revealing respective concentrations of 0.076 - 0.53, 0.015 - 0.36, 1.7 - 22, and 1.2 - 13 mu g g(-1). The proposed FASI-CZE method is a simple and promising procedure that is expected to be useful for the determination of PTPB and its degradation products in paint wastes.

    JAPAN SOC ANALYTICAL CHEMISTRY, Dec. 2012, ANALYTICAL SCIENCES, 28 (12), 1191 - 1196, English

    [Refereed]

    Scientific journal

  • Remediation of eutrophic sediments using industrial byproducts

    Satoshi ASAOKA, Tamiji YAMAMOTO, Hideo OKAMURA

    Dec. 2012, 4th IWA Young Water Professional Conference 2012, 330 - 333, English

    International conference proceedings

  • YANO YOSHIJI, HIRAI TETSUYA, OKAMURA HIDEO, KINOSHITA HIROAKI, NAKANO TAKESHI

    日本分析化学会, Oct. 2012, 分析化学, 61 (11), 925 - 930, Japanese

    [Refereed]

    Scientific journal

  • Hideo Okamura, Luvsantsend Togosmaa, Takuya Sawamoto, Keiichi Fukushi, Tomoaki Nishida, Toshio Beppu

    Copper pyrithione (CuPT2) and zinc pyrithione (ZnPT2) are two popular antifouling agents that prevent biofouling. Research into the environmental effects of metal pyrithiones has mainly focused on aquatic animal species such as fish and crustaceans, and little attention has been paid to primary producers. There have been few reports on residues in environmental matrices because of the high photolabile characteristics of the agents. Residue analyses and ecological effects of the metabolites and metal pyrithiones are not yet fully understood. This study was undertaken to assess the effects of CuPT2, ZnPT2, and six metabolites (PT2: 2,2'-dithio-bispyridine N-oxide, PS2: 2,2'-dithio-bispyridine, PSA: pyridine-2-sulfonic acid, HPT: 2-mercaptopyridine N-oxide, HPS: 2-mercaptopyridine, and PO: pyridine N-oxide) on a freshwater macrophyte. A 7-day static bioassay using axenic duckweed Lemna gibba G3 was performed under laboratory conditions. Toxic effects of test compounds were assessed by biomass reduction and morphological changes were determined in image analysis. Concentrations of ZnPT2 and CuPT2 and those of PT2 and HPT in the medium were determined by derivatizing 2,2'-dithio-bispyridine mono-N-oxide with pyridine disulfide/ethylene diamine tetra-acetic acid reagent that was equimolar with pyrithione. The toxic intensity of the compounds was calculated from the measured concentrations after 7-day exposure. ZnPT2, CuPT2, PT2, and HPT inhibited the growth of L. gibba with EC50 ranging from 77 to 140 mu g/l as calculated from the total frond number as the conventional index, whereas the other four metabolites had less effect even at 10 mg/l. The presence of the former four toxic derivatives resulted in abnormally shaped and unhealthily colored fronds, whose size was about 20% of the control fronds. EC50, calculated from the healthy frond area determined in image analysis, ranged from 10 to 53 mu g/l. Thus, image analysis as part of a duckweed bioassay can detect the toxic effects of pyrithione derivatives with 3-10 times higher sensitivity than the traditional index.

    SPRINGER, May 2012, ECOTOXICOLOGY, 21 (4), 1102 - 1111, English

    [Refereed]

    Scientific journal

  • OKAMURA HIDEO, Ai Tsuboi

    環境毒性学会, 2012, 環境毒性学会誌, 15 (2), 31 - 38, Japanese

    [Refereed]

    Scientific journal

  • OKAMURA HIDEO, Ai Tsuboi

    日本海水学会, 2012, 日本海水学会誌, 66 (5), 275 - 282, Japanese

    [Refereed]

    Scientific journal

  • Hirai,T, Kinoshita Y, OKAMURA HIDEO, Yano, Y, nakano, T

    2012, Bunseki Kagaku, 61 (11), 925 - 930, Japanese

    [Refereed]

    Scientific journal

  • Tomoyo Suda, Takayuki Hata, Shingo Kawai, Hideo Okamura, Tomoaki Nishida

    Tetracycline antibiotics are widely used in human and veterinary medicine; however, residual amounts of these antibiotics in the environment are of concern since they could contribute to selection of resistant bacteria. In this study, tetracycline (TC), chlortetracycline (CTC), doxycycline (DC) and oxytetracycline (OTC) were treated with laccase from the white rot fungus Trametes versicolor in the presence of the redox mediator 1-hydroxybenzotriazole (HBT). High performance liquid chromatography demonstrated that DC and CTC were completely eliminated after 15 min, while TC and CTC were eliminated after 1 h. This system also resulted in a complete loss of inhibition of growth of Escherichia coli and Bacillus subtilis and the green alga Pseudokirchneriella subcapitata with decreasing tetracycline antibiotic concentration. These results suggest that the laccase-HBT system is effective in eliminating tetracycline antibiotics and removing their ecotoxicity. (C) 2011 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, Jan. 2012, BIORESOURCE TECHNOLOGY, 103 (1), 498 - 501, English

    [Refereed]

    Scientific journal

  • Hideo Okamura, Masahiro Yagi, Masanobu Kawachi, Takeaki Hanyuda, Hiroshi Kawai, Iain Walker

    The environmental impact of two biocide-free antifouling paints, fluoropolymer and silicone types, painted on a test cylinder was assessed using a battery of ecotoxicity test and chemical analyses for organic micro-pollutants such as perfluoroalkyl substances (PFAS). A biocide paint containing zinc pyrithione (ZnPT2) and cuprous oxide was assessed as a positive control. A standardized laboratory rotating-cylinder method using each test cylinder with artificial seawater was performed for 45 days. After 1 h rotation, the leaked seawater was subjected for bioassay and chemical analyses twice weekly. The seawater extracts from the biocide paint showed adverse effects on bacteria, algae, and crustaceans, but those from the biocide-free paints did not. The leakage seawater from biocide-free paints, after 7-day continuous rotation, contained the same concentration levels of PFAS as blank seawater used to conduct the tests. Thus, no significant toxicities of the biocide-free paints were found under the conditions of this study. Simultaneous analysis of ZnPT2 and copper pyrithione (CuPT2) was developed using an HPLC with a polymeric resin column, showing that ZnPT2 was converted to CuPT2 by trans-chelation in the leakage seawater from the positive control paint. The experimental results using a laboratory rotating-cylinder method demonstrated that biocide-free paints did not markedly affect three species tested and no PFAS was detected. In contrast, biocide paint was significantly toxic to test species and toxicity of the extract on bacteria was partly responsible for CuPT2 produced in leakage seawater. Thus, a laboratory rotating-cylinder method may be applied for ecotoxicological assessment of antifouling paints.

    TAYLOR & FRANCIS LTD, 2012, TOXICOLOGICAL AND ENVIRONMENTAL CHEMISTRY, 94 (3), 545 - 556, English

    [Refereed]

    Scientific journal

  • Can Dimethyl Ether Diminish Environmental Impacts of Diesel Exhaust Particulates from Marine Diesel Oil?

    Hideo Okamura, Takuya Sawamoto, Tomohisa Dan, Hirotsugu Fujita

    Dimethyl ether (DME) can be added to marine diesel oil (MDO) or heavy fuel oil (HFO) to reduce green house gas emissions and diesel exhaust particulates (DEP=PM). The aim of this study was to clarify whether addition of DME to MDO or HFO could reduce environmental impacts of DEP in terms of toxic chemicals and toxicity. The soluble organic fraction (SOF) of DEP, obtained from M

    The Japan Institute of Mairne Engineering, Oct. 2011, The 9th International Symposium on Marine Engineering (ISME Kobe 2011), (C5-3), 1 - 4, English

    International conference proceedings

  • N. Tsunemasa, H. Okamura

    In September 2008, organotin (Ot) compounds were prohibited from being used worldwide. From 1997 onward in Japan, the production of paints containing TBT (tributylin) compounds was prohibited, and thus alternatives to Ot antifoulants have been used since then. It has been said that the decomposition characteristics of these materials are better than those of Ot compounds. The toxicity of alternative Ot antifoulants (e.g., diuron, irgarol 1051(A (R)), and Sea-Nine 211(A (R))) and Ot compounds (TBT and TPT (triphenyltin)), using oysters that inhabit a large area of Hiroshima Bay, were evaluated. The results showed that the toxicity of diuron and irgarol 1051 is very low, and the toxicity of Sea-Nine 211 is almost the same as that of TPT. Sea-Nine 211's effect was stronger on oysters than other shellfish, causing concern about the extent of Sea-Nine 211's impact on oyster development.

    SPRINGER, Jul. 2011, ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, 61 (1), 128 - 134, English

    [Refereed]

    Scientific journal

  • Takayuki Hata, Shingo Kawai, Hideo Okamura, Tomoaki Nishida

    The non-steroidal anti-inflammatory drugs diclofenac (DCF) and mefenamic acid (MFA) were treated with the white rot fungus Phanerochaete sordida YK-624. DCF completely disappeared and MFA decreased by about 90% after 6 days of treatment. It was also confirmed that the fungus almost completely removed the acute lethal toxicity of DCF and MFA towards the freshwater crustacean Thamnocephalus platyurus after 6 days of treatment. Mass spectrometric and H-1 nuclear magnetic resonance analyses demonstrated that two mono-hydroxylated DCFs (4'-hydroxydiclofenac and 5-hydroxydiclofenac) and one di-hydroxylated DCF (4',5-dihydroxydiclofenac) were formed via fungal transformation. The four metabolites of MFA were identified as 3'-hydroxymethylmefenamic acid (mono-hydroxylated MFA), 3'-hydroxymethyl-5-hydroxymefenamic acid (di-hydroxylated MFA), 3'-hydroxymethyl-6'-hydroxymefenamic acid (di-hydroxylated MFA) and 3'-carboxymefenamic acid. These results suggest that hydroxylation catalyzed by cytochrome P450 (CYP) in P. sordida YK-624 may be involved in the elimination and detoxification of DCF and MFA. This notion was further supported by the fact that smaller decreases in DCF and MFA were observed in cultures of P. sordida YK-624 incubated with 1-aminobenzotriazole, a known inhibitor of CYP.

    SPRINGER, Sep. 2010, BIODEGRADATION, 21 (5), 681 - 689, English

    [Refereed]

    Scientific journal

  • Takayuki Hata, Hideaki Shintate, Shingo Kawai, Hideo Okamura, Tomoaki Nishida

    Carbamazepine (CBZP) is used as an antiepileptic drug and is highly persistent. In this study, CBZP was treated with laccase from white rot fungus Trametes versicolor in the presence of a redox mediator 1-hydroxybenzotriazole (HBT). A single treatment with laccase and HBT eliminated CBZP by about 22% after 24 h, and repeated treatments with laccase and HBT, which were added to the reaction mixture every 8 h, helped eliminate about 60% of CBZP after 48 h. This suggests that repeated treatment is effective in eliminating CBZP. Mass spectrometric analyses demonstrated that two degradation products of CBZP, 10,11-dihydro-10,11-epoxycarbarnazepine and 9(10H)-acridone, were formed via repeated treatment with laccase and HBT. (C) 2010 Elsevier B.V. All rights reserved.

    ELSEVIER SCIENCE BV, Sep. 2010, JOURNAL OF HAZARDOUS MATERIALS, 181 (1-3), 1175 - 1178, English

    [Refereed]

    Scientific journal

  • Yukiko Inoue, Takayuki Hata, Shingo Kawai, Hideo Okamura, Tomoaki Nishida

    The antimicrobial and preservative agent triclosan (TCS) is an emerging and persistent pollutant with a ubiquitous presence in the aquatic environment. Thus. TCS was treated with manganese peroxidase (MnP), laccase and the laccase-mediator system with 1-hydroxybenzotriazole. MnP was most effective in eliminating TCS among the three enzymatic treatments, with TCS concentration being reduced by about 94% after 30 min following treatment with 0.5 nkat mL(-1) MnP and being almost completely eliminated after 60 min. Furthermore, MnP (0.5 nkat mL(-1)) caused the complete loss of bacterial growth inhibition by TCS after 30 min and reduced the algal growth inhibition of TCS by 75% and 90% after 30 and 60 min, respectively. These results strongly suggest that MnP is effective in removing the ecotoxicity of TCS. (C) 2010 Elsevier B.V. All rights reserved.

    ELSEVIER SCIENCE BV, Aug. 2010, JOURNAL OF HAZARDOUS MATERIALS, 180 (1-3), 764 - 767, English

    [Refereed]

    Scientific journal

  • Keiichi Fukushi, Yuki Yakushiji, Hideo Okamura, Youichi Hashimoto, Keiitsu Saito

    A commercial organoborane compound, pyridine-triphenylborane (PTPB), is often applied to ship hulls as an anti-fouling agent. We developed capillary zone electrophoresis (CZE) with direct UV detection for the simultaneous determination of PTPB and its estimated degradation products: diphenylborinic acid (DPB), phenylboronic acid (MPB), and phenol. The limits of detection (LODs) for PTPB, DPB, MPB, and phenol were, respectively, 25, 30, 50, and 29 mu g/l at a signal-to-noise ratio of three. At concentrations of 0.5 mg/l, values of the relative standard deviation (RSD, n = 6, intra-day) of peak area were obtained, respectively, for PTPB, DPB, MPB, and phenol, as 4.1, 4.1, 4.7, and 3.4% for peak heights 3.6, 3.2, 1.7, and 1.4%, and for migration times 1.1, 1.1, 1.0, and 0.73%. The analytes were detected within 14 min. Simple photodegradation experiments were conducted to verify the usefulness of the proposed method for additional FTPB degradation investigations. (C) 2010 Elsevier B.V. All rights reserved.

    ELSEVIER SCIENCE BV, Apr. 2010, JOURNAL OF CHROMATOGRAPHY A, 1217 (14), 2187 - 2190, English

    [Refereed]

    Scientific journal

  • Yuki Yakushiji, Keiichi Fukushi, Hideo Okamura, Youichi Hashimoto, Takashi Miyado, Keiitsu Saito

    A commercial organoborane compound, pyridine-triphenylborane (PTPB), is often applied to ship hulls as an anti-fouling agent in order to keep them free from marine organisms, such as barnacles and bivalves. However, the degradation process of PTPB and its degradation products have not been well understood, because of lack of an analytical method for both PTPB and its estimated degradation products. We previously developed a procedure using capillary zone electrophoresis (CZE) with direct UV detection for the simultaneous determination of PTPB and its estimated degradation products, such as diphenylborinic acid (DPB), phenylboronic acid (MPB), and phenol. For this study, simple degradation experiments were carried out to verify the usefulness of the proposed method for further PTPB degradation investigations. That is to say, PTPB samples dissolved in acetonitrile were put in the open air and a dark place to examine the effects of the light intensity and the temperature on the degradation of PTPB. The sample solutions were analyzed by the CZE method with the elapse of time. As a result, it was suggested that the degradation of PTPB was significantly affected by the light intensity, rather than the temperature. It has consequently been demonstrated that the CZE method is a useful tool to elucidate the degradation process of PTPB and its degradation products.

    JAPAN SOC ANALYTICAL CHEMISTRY, Apr. 2009, BUNSEKI KAGAKU, 58 (4), 301 - 304, Japanese

    [Refereed]

    Scientific journal

  • H. Okamura, S. Kitano, S. Toyota, H. Harino, K. V. Thomas

    Triphenylborane pyridine (TPBP) is an alternative to organotin antifouling compounds. This work aimed to identify the unknown Peak #1, and to evaluate the ecotoxicity of TPBP and its degradation products. Peak #1 was produced from TPBP dissolved in acetonitrile under UV-A photolysis using a high-pressure mercury lamp. The Peak #1 fraction was purified using two-step column chromatography from a TPBP-acetonitrile solution. The major compound of the fraction was identified as being biphenyl from the (1)H NMR and (13)C NMR spectra. The ecotoxicity of four degradation products (diphenylborane hydroxide, phenylborane dillydroxide, phenol, and biphenyl) and TPBP towards two marine planktons were assessed. The 48 h LC(50) values of the crustacean, Arternia salina, were 0.13 mg L(-1) for TPBP, 14 mg L(-1) for biphenyl, 17 mg L(-1) for phenol, and >50 mg L(-1) for the other degradation products. The 72 h EC(50) values of the diatom, Skeletonema costatum, were 0.0022 mg L(-1) for TPBP, 1.2 mg L(-1) for biphenyl, and >2 mg L(-1) for the other degradation products, Thus, the ecotoxicity of biphenyl and the other degradation products were not high compared to the parent compound, TPBP. (c) 2008 Elsevier Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Mar. 2009, CHEMOSPHERE, 74 (9), 1275 - 1278, English

    [Refereed]

    Scientific journal

  • 常政 典貴, 上野 博昭, 久保田 明利, 岡村 秀雄

    2008, 環境化学, 18 (1), 19 - 27, Japanese

    [Refereed]

    Scientific journal

  • Application of KU 5SDH-2 Pelletron Accelerator to Elememtary Analyses of Marine-Environmental Substances and Agricultural Products

    KITAMURA Akira, FURUYAMA Yuichi, TANIIKE Akira, OKAMURA Hideo, FUKUSHI Keiichi, HATTORI Satoshi

    Jul. 2007, Review of the Faculty of Maritime Sciences, Kobe University, No. 4, pp.147-154., Japanese

    Scientific journal

  • Xiaojian Zhou, Hideo Okamura, Shinichi Nagata

    The abiotic degradation of the new antifouling agent, triphenylborane pyridine (TPBP), was investigated in buffer solutions having different pH values (pH 5, 7, and 9), and in artificial and natural seawater to estimate environmental fate of TP13P. The TPBP in these waters was decomposed by a seven-day hydrolysis process at 50 degrees C both in the dark and a photolysis process under UV-A irradiation using a high-pressure mercury lamp for periods up to 24 h. TPBP hydrolysis was significantly enhanced by acidic pH solutions. The photolysis rate of TPBP was higher in acidic pH solutions than in neutral or basic pH solutions, and was highest in natural seawater, which could have contained naturally dissolved organic matter. Two degradation products, phenol and an unknown substance (Peak #1), were observed during the hydrolysis and photolysis studies of TPBP. The concentration of these substances after a one-day photolysis treatment was higher than after a seven-day hydrolysis treatment. The degradation rate of TPBP in the five test water samples was related to the simultaneous photolysis formation of phenol and Peak #1. However, the degradation rate of TPBP was not related to the formation of the hydrolysis products. Therefore, it is suggested that photodegradation of TPBP follows a different pathway to the hydrolysis degradation of TPBP. Our results indicate the chemical and photochemical reaction of TPBP in water occurs in natural aquatic environments. (c) 2006 Elsevier Ltd. Ali rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, May 2007, CHEMOSPHERE, 67 (10), 1904 - 1910, English

    [Refereed]

    Scientific journal

  • Hiroya Harino, Yoshikazu Yamamoto, Sayaka Eguchi, Shini'chiro Kawai, Yuko Kurokawa, Takaomi Arai, Madoka Ohji, Hideo Okamura, Nobuyuki Miyazaki

    Organotin compounds (OTs) and representative booster biocides were measured in sediment and mussels from Otsuchi Bay, Japan. The mean amounts of tributyltin (TBT) and triphenyltin (TPT) compounds in sediment were 13 mu g kg(-1) dry and 3 mu g kg(-1) dry, respectively. Representative booster biocides (Sea-Nine 211, Diuron, Dichlofluanid, Irgarol 1501, M1, which is a degradation compound of Irgarol 1051, and Copper pyrithione) were also detected in sediment from Otsuchi Bay. OT concentrations were higher than those of the measured booster biocides. Otsuchi Bay was divided into four parts by cluster analysis based on OT concentrations in sediment sampled from the bay. These areas included the vicinity of a shipyard, a small fishing port, the closed inner area of the bay, and the mouth of the bay. Higher concentrations of TBT and TPT and a higher ratio of TBT to total BTs were observed in the vicinity of the shipyard. A higher concentration of TPT in comparison with TBT was detected in a small fishing port. Furthermore, OT concentrations in the mouth of the bay were higher than those in the closed-off section. OT concentrations in mussels decreased with distance from the shipyard. Otsuchi Bay was then divided into three parts by cluster analysis based on the concentrations of representative booster biocides found in the bay's sediment. These areas included the vicinity of a shipyard, a small fishing port, and other sites. Concentrations of Diuron and Irgarol 1051 in the vicinity of a shipyard and a small fishing port were dramatically high in comparison with the other sites. Copper pyrithione and Dichlofluanid in addition to Diuron and Irgarol 1051 were also detected in the area of a small fishing port. The concentrations of antifouling biocides were highest in the water in front of the shipyard and showed a marked decrease with distance from the shipyard.

    SPRINGER, Feb. 2007, ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, 52 (2), 179 - 188, English

    [Refereed]

    Scientific journal

  • 西川 崇紘, 岡村 秀雄, 磯貝 恭史, 小野 雄策, 倉田 泰人, 渡辺 洋一, 毛利 紫乃, 小野 芳朗

    2007, 環境科学会誌, 20 (6), 493 - 501, Japanese

    [Refereed]

    Scientific journal

  • Xiaojian Zhou, Hideo Okamura, Shinichi Nagata

    Toxicities of antifouling chemicals and natural marine samples were evaluated by three assays, among which bioluminescence assay using freshly incubated Vibrio fischeri (V. fischeri) cells (NZ assay) and MicroTox were regarded as short-term assays, and growth inhibition assay was conducted as long-term assay. Short-term toxicity levels evaluated by NZ assay were in good agreement with those by MicroTox assay for all of the samples examined. Based on the EC50 values of each chemical by respective assay, NZ assay showed prior reproducibility and similar levels of sensitivity when compared with those of MicroTox assay. On the other hand, growth inhibition assay showed lower sensitivity and reproducibility than NZ and MicroTox assays. Four kinds of antifouling chemicals, Irgarol 1051, Diuron, thiabendazole (TBDZ), and N-dichlorofluoromethylthio-N ',N '-dimethyl-N-phenylsulfamide (DCF), were detected to possess delayed toxicity from the judgments on the difference of short-term and long-term toxicities. Four out of 16 seawater samples collected in Japan showed remarkable toxicity in NZ assay, suggesting that they were contaminated by several types of antifouling chemicals. Considering time consumed, facility for operation, cost, and requirements, NZ assay was proved to be efficient for toxicity evaluations for artificial and natural samples.

    PHARMACEUTICAL SOC JAPAN, Dec. 2006, JOURNAL OF HEALTH SCIENCE, 52 (6), 811 - 816, English

    [Refereed]

    Scientific journal

  • The impacts on marine environments by the biocides in ship antifouling paints

    Xiaojian Zhou, Hideo Okamura, Shinichi Nagata

    Biocides are added into ship paints to protect ship's hull against the settlement of fouling organisms. But these biocides, named as antifouling chemicals, may also affect the non-target organisms in marine environments. TBT was applied as antifouling, chemical for many decades but found to be extremely harmful to marine ecosystem. Therefore, it was prohibited to use by International Maritime Organization (IMO) from 2003. In this study, the toxicity of several types of antifouling chemicals against aquatic organisms was discussed. The results showed that these chemicals possess serious inhibitory activity on bacteria, micro-algae, fish, and crustacean. Further the degradation of these biocides were studied, some of them possibly possess the abilities of hydrolysis and photolysis, which may enable the reduction of their concentrations in marine environments. Since usage of antifouling chemicals will continue until suitable alternative technology is developed, the degradation ability of antifouling chemical should be considered as an important factor to be granted for application in ship paints.

    JILIN SCI TECHNOL PUBL HOUSE, 2006, Progress of Green Oxidation/Reduction Technologies, pp. 468-473, 468 - 473, English

    [Refereed]

    International conference proceedings

  • Hideo Okamura, Naomasa Kobayashi, Masamitsu Miyanaga, Yusaku Nogami

    dZinc pyrithione (ZnPT) or copper pyrithione (CuPT) have been effectively used as ship-antifouling agents, as an alternative to organotin compounds. Because of their instability in light and a lack of suitable analytical procedures, there is little data on their residue levels in environmental matrices. It is possible to investigate the fate of such compounds by toxicity alteration with certain treatments. The purpose of this study was to evaluate the degradation of pyrithiones through toxicity reduction by near ultraviolet (UV-A) irradiation. Metal pyrithiones dissolved in acetonitrile were irradiated with a UV-A lamp for 0, 0.5, 1, and 2 h, and were subjected to UV spectral measurement and toxicity evaluation using both sea urchin and freshwater rotifer bioassays. For the bioassays, photolyzed samples were dissolved in dimethyl sulfoxide after evaporation of the acetonitrile. The changes in UV spectra of photolyzed ZnPT or CuPT showed a time-dependent degradation, and the UV spectra at 2 h irradiation suggested substantial decomposition. Toxicities of ZnPT and CuPT were 12 and 5 mu g/L as 24 h LC50 to the survival of rotifers and 10(-6) ng/L and 2.3 ng/L as 27 h EC50 to normal pluteus formation, respectively. By evaporation of the acetonitrile, the EC50 of ZnPT was 2.2 ng/L, which was the same as that of CuPT. The EC50s of ZnPT or CuPT for both species increased with longer irradiation times. Photolyzed ZnPT or CuPT demonstrated substantial degradation in the UV spectra, but possessed marked toxicity, which is probably due to toxic degradation products. One reason why photolyzed CuPT was toxic to rotifers was explained by the high toxicity of copper ions formed by UV-A irradiation. (c) 2006 Wiley Periodicals, Inc.

    JOHN WILEY & SONS INC, Aug. 2006, ENVIRONMENTAL TOXICOLOGY, 21 (4), 305 - 309, English

    [Refereed]

    Scientific journal

  • XJ Zhou, H Okamura, S Nagata

    A bioluminescent assay using Vibrio fischeri Deutsche Sammlung von Mikroorganismen (DSM) 7151 was applied to evaluate the toxicities of some new antifouling chemicals. First, the efficient concentration, led to 50% inhibition of bioluminescence (EC50) values of the single antifouling chemicals zinc 2-pyridinethiol-1-oxide (Zn-pt), copper 2-pyridinethiol-1-oxide (Cu-pt), CuSO4, zinc bis(N,N'-dimethyl)-dithiocarbamate (Ziram), 4,5-dichloro-2-(n-octyl)-3(2H)-isothiazolone (SeaNine 211), pyridine triphenylboron (PTPB), 3-iodo-2-propynyl butylcarbamate (IPBC), 3-(3,4-dichlorophenyl)-1,1-dimethylurea (Diuron), dichlofluanid (N-dichlorofluoromthylthio-N',N'-dimethyl-N-phynylsulfamide) (DCF), and 2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine (Irgarol 1051) were determined to be 0.08, 0.12, 0.22, 0.31, 0.35, 0.75, 8.49, 12.74, 39 and > 40 mg/l at 30 min of incubation, respectively. Then, 45 different combinations composed of two antifoulants each were evaluated. Based on the EC50 values at 30 min of incubation, typical patterns of interaction for the combinations were classified into three groups based on the comparison of inhibition difference between single chemicals and their mixtures. Mixture toxicity indices were also introduced to examine the interaction effect of each combination. The results showed that most combinations were partially additive, and there was no antagonistic effect among the present combinations of chemicals. Additive effects were observed in the case of Diuron, PTPB, or SeaNine 211 when mixed with IPBC. Marked synergistic effects were observed for Irgarol 1051, Ziram, Zn-pt, and Cu-pt when mixed with Cu2+, which will make these chemicals more toxic against organisms in marine environments.

    PHARMACEUTICAL SOC JAPAN, Jun. 2006, JOURNAL OF HEALTH SCIENCE, 52 (3), 243 - 251, English

    [Refereed]

    Scientific journal

  • Noritaka Tunemasa, Kazuhisa Hashimoto, Yuichiro Yamaoka, Hiroaki Ueno, Hideo Okamura

    2006, Environmental Chemistry, 16 (2), 201 - 211, Japanese

    [Refereed]

    Scientific journal

  • N Kobayashi, H Okamura

    Interactive toxic effects between heavy metals were investigated using a sea urchin (Anthocidaris crassispina) bioassay. An effluent from an abandoned mine showed significant inhibitory effects on embryo development as well as producing specific malformations. The effects on the embryos were reproduced by synthetic polluted seawater consisting of eight metals (manganese, lead, cadmium, nickel, zinc, chromium, iron, and copper) at the concentrations detected in the mine effluent. This indicated that the heavy metals were responsible for the effects observed. Five heavy metals were ranked in decreasing order of toxicity as follows: Cu > Zn > Pb > Fe > Mn. Among these, zinc and manganese could cause malformation of the embryos. From bioassay results using 27 combinations of heavy metals, 16 combinations including zinc could produce specific malformations, such as radialized, exo-gastrulal, and spaceship Apollo-like gastrulal embryos. Zinc was one of the elements responsible for causing malformations and its effects were intensified by the presence of the other metals, such as manganese, lead, iron, and copper. (c) 2005 Elsevier Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Dec. 2005, CHEMOSPHERE, 61 (8), 1198 - 1203, English

    [Refereed]

    Scientific journal

  • Marine Environment Symposium: Conservation and bioassay using marine organisms

    Shosaku Kashiwada, Hideo Okamura

    2005, J.Environ.Science, 18(2): 127-128., Japanese

    International conference proceedings

  • WJ Shim, UH Yim, NS Kim, SH Hong, Oh, JR, JK Jeon, H Okamura

    Triphenyltin (TPT) and tributyltin (TBT) concentrations were determined in two starfish species (Asteriapectinffra and Asterias amurensis), bivalves (Crassostrea gigas or Mytilus edulis), and seawater samples from sites around the coasts of Korea. Both TPT and TBT concentrations in starfish ranged from 8 to 1560 ng/g and from < 2 to 797 ng/g as Sri on a dry weight basis, respectively. TPT concentration accounted for 75.4% and 86.4% of total phenyltin concentration in A. pectinifera and A. amurensis, respectively, while monobutyltin, a degradation product of TBT, accounted for 86.3% and 57.2% of total butyltin, respectively. Triphenyltin concentrations in A. pectinifera were significantly correlated to water and bivalve TPT concentrations, which implies that dietary uptake of TPT from contaminated prey as well as direct uptake from surrounding water contribute to TPT body residues in the starfish. Starfish could be target organisms for monitoring TPT compound in the marine environment, due to their high accumulation and low degradation capacity towards TPT. (C) 2004 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, Feb. 2005, ENVIRONMENTAL POLLUTION, 133 (3), 489 - 499, English

    [Refereed]

    Scientific journal

  • H Okamura, Y Sugiyama

    Irgarol 1051 (2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine) is a herbicide analogue that is added to antifouling agents used on ships. Our former study on its degradation in sunlight suggested that unknown photosensitizers in natural waters accelerated the photodegradation to the degradation product, M1. In this study, the photodegradation of Irgarol in water was investigated in the presence of some photosensitizers. Test water containing Irgarol or M1, with or without photosensitizers, was irradiated with light from a UV-A fluorescent lamp for 48 h. The concentrations of Irgarol and M1 in the test water were determined by HPLC after solid-phase extraction. M1 was more stable than Irgarol when irradiated in the presence of photosensitizers such as acetone, benzophenone, tryptophan, and rose bengal. Hydrogen peroxide (HP) accelerated the photodegradation of Irgarol, and the product M1 was degraded in the presence of more than 100 mg l(-1) HP after 10 h. Natural humic substances (NHS) also accelerated the photodegradation of Irgarol, but in this case, the product M1 persisted even when Irgarol was completely degraded. Photosensitized degradation of Irgarol by NHS may result in the accumulation of M1 in aquatic environments. (C) 2004 Elsevier Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Nov. 2004, CHEMOSPHERE, 57 (7), 739 - 743, English

    [Refereed]

    Scientific journal

  • N Kobayashi, H Okamura

    The toxicity of the polluted waters originating from a disused lead mine was evaluated using both sea urchin bio-assays and heavy metal analysis. Samples from three polluted waters (a seawater and two freshwaters) were collected from the mine area and one seawater sample was taken from a non-contaminated reference site. The test waters contained higher concentrations of heavy metals such as manganese, lead, cadmium, zinc, chromium, nickel, iron, and copper than did ambient seawater. The three test waters had inhibitory effects, in a dose-dependent manner, on the first cleavage of sea urchin embryos and on pluteus formation during the development. Some malformations, such as a radialized pluteus, exo-gastrula, and spaceship Apollo-like embryos were induced by the test waters without dilution. Zinc alone also induced the same anomaly. Zinc in the test seawater was ascertained as one of the metals that caused the anomalies, but not all of the toxicity was caused by zinc. It was speculated that interactive effects, involving zinc and possibly manganese and nickel, were occurring. (C) 2003 Elsevier Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Jun. 2004, CHEMOSPHERE, 55 (10), 1403 - 1412, English

    [Refereed]

    Scientific journal

  • N Ogawa, H Okamura, H Hirai, T Nishida

    Irgarol 1051 (2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine), a derivative of s-triazine herbicide, is an antifouling compound used as an alternative to organotins. The compound is highly persistent and is known to be biodegraded only by the white rot fungus, Phanerochaete chrysosporiunt. We used partially purified manganese peroxidase (MnP) prepared from P. chrysosporium to evaluate its capacity to degrade Irgarol 1051. MnP degraded Irgarol 1051 to two major products, one identified as M1 (identical to GS26575, 2-methylthio-4-tert-butylamino-6-amino-striazine) and the other not identified but with same mass spectrum as M1 and a different ultraviolet spectrum. This report clearly demonstrates that this ligninolytic enzyme is involved in the degradation of Irgarol 1051. (C) 2003 Elsevier Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Apr. 2004, CHEMOSPHERE, 55 (3), 487 - 491, English

    [Refereed]

    Scientific journal

  • Effects of TBT-substitute antifouling agents on marine plankton species

    Hirohisa Mieno, Hideo Okamura, Noritaka Tunemasa

    2004, Irrigation and effluent, 46: 1031-1036, Japanese

    [Refereed]

    Scientific journal

  • Hideo Okamura, Shino Mohri, Masato Yamada, Yuzo Inoue, Hirohisa Mieno, Yuuki Ito, Ai Fujita

    2004, Environmental Science, 17 (6), 451 - 460, Japanese

    [Refereed]

    Scientific journal

  • Mingo Park, Hideo Okamura, Isao Aoyama, Miki Sudo, Takuya Okubo, Masahisa Nakamura

    2004, Jap. J. Environ. Toxicology, 7 (1), 23 - 33, Japanese

    [Refereed]

    Scientific journal

  • Photosensitized degradation of Irgarol 1051 in water.

    Okamura, H

    Jan. 2004, Proceedings in International Symposium on Antifouling paint and Marine Environment (InSAfE), 223-227

    [Refereed]

    International conference proceedings

  • Ecotoxicity of seawater in and out dockyards

    H Okamura, A Fujita, H Harino, Zhou, X, S Nagata, Y Yano, K Ishida

    Seawater pollution around dockyards was assessed by two kinds of standard bioassay and chemical analysis targeting new antifouling compounds. Seawater samples were collected at thirteen sites in and out dockyards in 2003. Ecotoxicity of the samples without concentration was assessed using marine microalgae Skeletonama costatum and marine crustacean Artemia salina. All the samples had no significant effects on crustacean. Four samples collected in the dock before and after repair practice with sandblast had severe toxic effects on algal growth with low 72-hour EC50s. Chemical analysis showed the toxic seawater contained three antifouling compounds such as Diuron, Irgarol 1051, and Irgarol's metabolite M1. The concentrations in the seawater were ranging 51 similar to 85 mu g/L for Diuron, 2.4 similar to 25 mu g/L for Irgarol, and 1.4 similar to 19 mu g/L for M1. It was speculated that both Diuron and Irgarol were responsible for the toxicity of seawater according to the relationship between the residue concentrations and the EC50s obtained from algal bioassay. The experimental results clearly indicated that the state-of-the-art practice at dockyard could discharge contaminants to marine environment around the dockyards. It is needed to minimize toxic discharge from dockyards.

    IEEE, 2004, OCEANS '04 MTS/IEEE TECHNO-OCEAN '04, VOLS 1- 2, CONFERENCE PROCEEDINGS, VOLS. 1-4, 1793-1796, 1793 - 1796, English

    [Refereed]

    International conference proceedings

  • H Okamura, T Nishida, Y Ono, WJ Shim

    SPRINGER-VERLAG, Nov. 2003, BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, 71 (5), 881 - 886, English

    Scientific journal

  • H Okamura, Aoyama, I, Y Ono, T Nishida

    Residue analyses of some antifouling herbicides (Diuron, Irgarol 1051 and the latter's degradation product M1, which is also known as GS26575), were conducted in waters collected along the coast of western Japan. In total, 142 water samples were collected from fishery harbours (99 sites), marinas (27 sites), and small ports (16 sites) around the Seto Inland Sea, the Kii Peninsula, and Lake Biwa, in August 1999. A urea-based herbicide, Diuron, was positively identified for the first time in Japanese aquatic environments. Diuron was detected in 121 samples (86%) up to a highest concentration of 3.05 mug/l, and was found in 86% of samples from fishery harbours, 89% from marinas, and 75% from ports. Four freshwater samples out of 11 collected at Lake Biwa contained Diuron. Neither Irgarol 1051 nor M1 was found in the lake waters, but both were found in many coastal waters. Irgarol 1051 was found in 84 samples (60%) at a highest concentration of 0.262 mug/l. The concentrations detected were of similar magnitude to those in our previous surveys, taken in 1997 and 1998. M1 was found in 40 samples (28%) up to a highest concentration of 0.080 mug/l. The concentrations detected were generally lower than those found in our previous surveys. The detection frequency among fishery harbours, marinas, and ports was 57-70% for Irgarol 1051 and 25-30% for M1. Ninety-five per cent of the coastal waters in which M1 was detected also contained Irgarol 1051, and 93% of the samples in which Irgarol 1051 was detected also contained Diuron. These results clearly suggest that commercial ship-bottom paints containing both Diuron and Irgarol 1051 are used extensively in the survey area. (C) 2003 Elsevier Science Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, 2003, MARINE POLLUTION BULLETIN, 47 (1-6), 59 - 67, English

    Scientific journal

  • N Kobayashi, H Okamura

    Tributyltin oxide (TBTO) has been used worldwide in marine antifouling paints as a biocide for some time. However, it produced toxic effects, especially in marine water/sediment ecosystems. Consequently, its use in antifouling paints has been prohibited in many countries. In this study, the toxicity of alternative and/or new antifouling biocides compared with TBTO is assessed by a biological method. The effects of these chemicals on marine species have not been well studied. This paper assesses, comparatively, the effects of eight biocides on sea urchin eggs and embryos. The chemicals assessed were TBTO, Irgarol 1051, M I (the persistent degradation product of Irgarol), Diuron, zinc pyrithione, 'KH101', 'Sea-Nine 211', and copper pyrithione. For these chemicals, toxicity appears to be in the order zinc pyrithione > Sea-Nine 211 > KH101 > copper pyrithione > TBTO > Diuron similar to Irgarol 1051 > M1. Here, we show that zinc pyrithione, Sea-Nine 211, KH101, and copper pyrithione are much more toxic to sea urchins than TBTO or the other chemicals. (C) 2002 Elsevier Science Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Aug. 2002, MARINE POLLUTION BULLETIN, 44 (8), 748 - 751, English

    [Refereed]

    Scientific journal

  • H Okamura

    The antifouling compound Irgarol 1051 and its degradation product M1 (also known as GS26575), along with another antifouling compound Diuron, have recently been found in Japanese coastal waters. This study was undertaken to find the origin of these chemicals and investigate their aquatic fate. Five glass plates, each coated with I g of antifouling paint containing Irgarol and Diuron, were submerged in 250 ml of five different test waters and the plates removed after several months. The aqueous solutions were divided into two groups: one exposed to natural sunlight, and the other kept in the dark as a control. Irgarol and Diuron were detected in all aqueous solutions, suggesting leaching from antifouling paints is the origin of these antifouling biocides found in Japanese coastal waters. Under sunlight conditions, Irgarol underwent a rapid degradation to produce M1, which remained even after Irgarol had disappeared from the system. These compounds were persistent in any aqueous solutions tested under dark conditions, indicating high stability to hydrolysis. Diuron and M I were more persistent than Irgarol under sunlight irradiation. Since these compounds have high herbicidal activities, their ultimate impact on aquatic ecosystems is closely related to their aquatic fate. (C) 2002 Elsevier Science Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Jul. 2002, CHEMOSPHERE, 48 (1), 43 - 50, English

    [Refereed]

    Scientific journal

  • H Okamura, T Watanabe, Aoyama, I, M Hasobe

    A simple, rapid toxicity test was developed using the suspension-cultured fish cell line CHSE-sp derived from chinook salmon Oncorhynchus tshawytscha embryos in order to assess the toxicity of new marine antifouling compounds. The compounds tested were copper pyrithione, Diuron, Irgarol 1051, KH101, Sea-Nine 211, and zinc pyrithione, all of which have been nominated in Japan as possible replacements for organotin compounds. The in vitro acute toxicity (24h EC50) of the six compounds to these fish cells was evaluated using the dye Alamar Blue(TM) to determine cell viability, and then correlated with the results of in vivo chronic toxicities (28-day LC50) to juvenile rainbow trout Oncorhynchus mykiss. The suspension-cultured fish cells were found to be suitable for the screening of such chemicals before performing an in vivo test. The toxicities of the test compounds obtained from both tests, shown in decreasing order, were as follows: copper pyrithione > zinc pyrithione > KH101 > Sea-Nine 211 greater than or equal to Diuron > Irgarol 1051. The herbicides Diuron and Irgarol 1051 showed the least toxicity, while the pyrithiones had the greatest toxicity. (C) 2002 Elsevier Science Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Feb. 2002, CHEMOSPHERE, 46 (7), 945 - 951, English

    [Refereed]

    Scientific journal

  • Hideo Okamura, 小野 芳朗, 加納 佐江子, 剣持 堅志

    2002, 廃棄物学会誌, 13(6): 370-378, Japanese

    [Refereed]

    Scientific journal

  • H Okamura, M Piao, Aoyama, I, M Sudo, T Okubo, M Nakamura

    An ecotoxicological Study of river water discharged from the agricultural area around Lake Biwa was performed by using algal bioassays to guide chemical analysis. Water samples were collected once a week, at least, for 1 year starting in April 1997 and continuing, until April 1998. The toxicities of the dissolved and particulate-adsorbed extracts of water samples were evaluated by the algal growth inhibition test and concentrations of individual pesticides were determined. Most of the river water that was collected during the periods when pesticides were applied to the paddy fields caused algal growth inhibition. Some extracts were found to contain herbicides (molinate, mefenacet, simetryn, or esprocarb) as major compounds. According to chemical assay and bioassay, simetryn was identified as the most toxic compound that caused algal growth inhibition. (C) 2002 Elsevier Science Ltd. All rights reserved.

    ELSEVIER SCI LTD, 2002, ENVIRONMENTAL POLLUTION, 117 (3), 411 - 419, English

    [Refereed]

    Scientific journal

  • Ecotoxicological assessment of agricultural land runoff around Lake Biwa, Japan.

    Okamura, H, Piao, M, Aoyama, I, Sudo, M, Okubo, T, Nakamura, M

    Nov. 2001, Proceedings in 9th International Conference on the Conservation and Management of Lakes. Ohtsu, Japan.

    [Refereed]

    International conference proceedings

  • 明石 竹弘, 岡村 秀雄, 青山 勳

    2001, 環境毒性学会誌, 4 (1), 19 - 28, Japanese

    [Refereed]

    Scientific journal

  • Pesticides in the aquatic environment- Fate, ecotoxicity, and risk assessment.

    Okamura, H, Aoyama, I

    2001, Proceedings in International symposium on Bioresources and Environmental Stress., 17-20

    [Refereed]

    International conference proceedings

  • D Liu, RJ Maguire, YL Lau, GJ Pacepavicius, H Okamura, Aoyama, I

    Microbial degradation is one of the most important processes responsible for the removal of chemical contaminants from the environment. Since the aquatic compartment is frequently the ultimate depository for many man-made substances, there is a need to understand factors that control and/or affect the rate of biodegradation for chemical substances in the aquatic environment. In this study, several priority chemicals encompassing various biocides (2,4-dichlorophenoxy acetic acid, carbaryl, fenitrothion, pentachlorophenol) and a nitroaromatic (2,4-dinitrotoluene were assessed for their biodegradability in cyclone fermenters under aerobic and anaerobic conditions, with and without co-metabolites. Among those factors investigated, aerobic and anaerobic conditions, availability of co-metabolites, and pre-exposure of microorganisms to the test chemical were found to be the most significant elements in controlling the rate of biodegradation. Other factors (e.g., acclimation period) requiring attention in calculating the rate of biodegradation were also discussed. (C) 2000 by John Wiley & Sons, Inc.

    JOHN WILEY & SONS INC, Dec. 2000, ENVIRONMENTAL TOXICOLOGY, 15 (5), 476 - 483, English

    [Refereed]

    Scientific journal

  • H Okamura, Aoyama, I, D Liu, RJ Maguire, GJ Pacepavicius, YL Lau

    Residue analyses and ecotoxicity assessment were conducted on the new antifouling compound Irgarol 1051 (2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine) and its degradation product M1 (2-methylthio-4-tert-butylamino-6-amino-s-triazine) in order to delineate the environmental fate and impact of Irgarol 1051 on the aquatic ecosystem. For the first time, the Irgarol degradation product (M1) was positively identified in environmental samples. During the 1998 Irgarol survey, concentrations of M1 (up to 1870 ng/l) were generally higher than those of Irgarol in the coastal waters of the Seto Inland Sea in Japan, suggesting a greater environmental persistence for M1 than for the parent compound Irgarol 1051 in the aquatic ecosystem. Ecotoxicity testing revealed that Irgarol 1051 and M1 were moderately toxic to a marine bacterium and the four crustaceans tested, but were highly toxic to some algae and higher plants. In the root elongation inhibition bioassay, M1 showed a phytotoxicity at least 10 times greater than that of Irgarol and six other triazine herbicides (terbutryn, terbutylazine, terbumeton, simetryn, atrazine and simazine). These results strongly suggest that both Irgarol 1051 and its persistent degradation product M1 may potentially affect and/or damage the primary producer community in aquatic ecosystems. To safeguard the aquatic ecosystem from the damaging impact of micro contaminants, it is recommended that, besides monitoring for the target parent compound, major degradation products should also be included in environmental surveys. Otherwise, then is a risk of underestimating the ultimate impact of a particular toxicant on the environment. (C) 2000 Elsevier Science Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Oct. 2000, WATER RESEARCH, 34 (14), 3523 - 3530, English

    [Refereed]

    Scientific journal

  • H Okamura, Aoyama, I, T Takami, T Maruyama, Y Suzuki, M Matsumoto, Katsuyama, I, J Hamada, T Beppu, O Tanaka, RJ Maguire, D Liu, YL Lau, GJ Pacepavicius

    The phytotoxicity of the new antifouling compound Irgarol 1051 (2-methylthio-4-tert-butylamino-6-cycloamino-s-triazine) and its degradation product M1 (2-methylthio-3-tert-butylamino-6-amino-s-triazine) was assessed by a battery of bioassays with marine and freshwater species, Both compounds at low concentrations affected aquatic plant species such as the red macroalga Porphyra yezoensis conchospores, the brown macroalga Eisenia bicyclis gametophytes, the freshwater green microalga Closterium ehrenbergii, the floating macrophytes Lemna gibba G3 and Lemna minor 1769, The toxicity of Irgarol 1051 was higher than that of M1 for all the aquatic plant species tested, but MI showed a higher toxicity to root elongation of a terrestrial plant. The NOEC (0.3 mu g/l) of Irgarol to the brown seaweed was identical to the maximum concentration (0.296 mu g/l) detected in Japanese coastal waters, and the maximum concentration of M1 (1.87 mu g/l) detected amounted to only 20% of the NOEC value. The bioassay results suggest the possibility that both Irgarol 1051 and M1 may influence the primary producer community in the aquatic environment, (C) 2000 Elsevier Science Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Sep. 2000, MARINE POLLUTION BULLETIN, 40 (9), 754 - 763, English

    [Refereed]

    Scientific journal

  • 朴 明玉, 岡村 秀雄, 羅 栄, 青山 勳

    2000, 環境毒性学会誌, 3 (1), 23 - 32, Japanese

    [Refereed]

    Scientific journal

  • 西田 友昭, 堤 祐司, 毛見 誠, 羽田 崇, 岡村 秀雄

    1999, 水環境学会誌, 22 (6), 465 - 471, Japanese

    [Refereed]

    Scientific journal

  • 岡村 秀雄, 青山 勳, Liu, D

    1999, 環境技術, 28(5): 315-319, Japanese

    [Refereed]

    Scientific journal

  • 小野 芳朗, 岡村 秀雄, 河原 長美, 青山 勳, 小田 美光

    1999, 水環境学会誌, 22 (7), 561 - 567, Japanese

    [Refereed]

    Scientific journal

  • Photodegradation of Irgarol 1051 in water

    H Okamura, Aoyama, I, D Liu, J Maguire, GJ Pacepavicius, YL Lau

    The photodegradation of a novel antifouling agent with high algicidal activity, Irgarol 1051 (2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine), has been investigated. Irgarol 1051 is fairly stable toward hydrolysis in water, and has been detected in European coastal and lake waters since its introduction in the late 1980's. Irgarol 1051 dissolved in six different aqueous solutions was exposed to solar irradiation for 6 months. Its rates of photodegradation in natural sea water and river water were much higher than those in pure water and buffered solutions (pH 5, 7, and 9). It appears that unknown photosensitizers in the natural waters accelerated the photodegradation of Irgarol 1051. Three significant photodegradation products ("RT5.8", "RT7.8", and "RT8.7") were observed. The degradation product RT7.8 was produced just in the natural waters and persisted for only several weeks. The other two degradation products (RT5.8 and RT8.7) were much more stable, even after 6 months irradiation. The latter (RT8.7) was produced mainly in buffer solutions, and the former (RT5.8) was produced in all the 6 aqueous solutions tested and was identified by GC-MS analysis as the compound 2-methylthio-4-tert-butylamino-6-amino-s-triazine, which had been found as a biodegradation product during the fungal biotransformation of Irgarol 1051. Thus biodegradation and photodegradation processes in natural waters both have the same major degradation product.

    MARCEL DEKKER INC, 1999, JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART B-PESTICIDES FOOD CONTAMINANTS AND AGRICULTURAL WASTES, 34 (2), 225 - 238, English

    [Refereed]

    Scientific journal

  • D Liu, GJ Pacepavicius, RJ Maguire, YL Lau, H Okamura, Aoyama, I

    Irgarol 1051, 2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine, is a newly developed herbicidal additive for use in copper-based antifouling paints. It is intended to replace the antifouling agent tributyltin, which has been regulated internationally due to its severe impact on the aquatic ecosystem. However, there is no information in the open literature on the abiotic degradation of Irgarol, a fact that hinders the assessment of its ultimate impact on the environment. This study showed that mercuric chloride was capable of rapidly catalyzing the hydrolysis of Irgarol 1051 in distilled water and buffer solutions. The degradation appeared to follow the reaction of a catalyzed hydrolysis and was not significantly affected by the pH tested (5 to 9). All other 5 heavy metal salts tested (AgNO3, CdCl2, CuSO4, PbCl2 and ZnCl2) had practically no catalytic property on Irgarol hydrolysis, implying the involvement of a specific activity for Hg2+ in this reaction. The mechanism for the catalyzed hydrolysis may be the formation of bidentate chelation through nitrogen: (No. 5) on the ring and the nitrogen on the cyclopropyl-amino side chain in Irgarol 1051 with the Hg2+ ion. The resulting four member chelate complex would weaken the cyclopropyl-amino bond considerably, thus facilitating the hydrolysis reaction. Ultraviolet spectroscopy of the reaction mixtures and the identification of Irgarol hydrolysis product M1 (2-methylthio-4-tert-butylamino-6-amino-s-triazine) by GC-MS and LC-MS provided the basis for the proposed mechanism on the HgCl2-catalyzed hydrolysis of Irgarol 1051. M1 appeared to be more stable than the parent compound Irgarol 1051, thus implying its possible accumulation in the environment. One practical aspect of this work is that HgCl2 should not be used in preserving water samples in Irgarol 1051 monitoring programs. (C) 1998 Elsevier Science Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Jan. 1999, WATER RESEARCH, 33 (1), 155 - 163, English

    [Refereed]

    Scientific journal

  • Okamura, H, Omori, M, Luo, R, Aoyama, I, Liu, D

    1999, Total Environ., 234 (1/3), 223 - 231

    [Refereed]

    Scientific journal

  • D Errampalli, H Okamura, H Lee, JT Trevors, JD van Elsas

    The green fluorescent protein (encoded by gfp gene) was used as a marker to estimate survival of a phenanthrene-degrading Pseudomonas sp, UG14Gr in a creosote-contaminated soil from Alberta, Canada, The gfp was integrated via Tn5 transposition into the chromosome of UG14r and resultant gfp-marked colonies were identified by green fluorescence emission under UV light. The gfp was stably maintained in UG14Gr and the gfp insertion had no apparent adverse effect on the metabolic capability of the marked isolate, which showed unhindered ability to mineralize C-14-labelled phenanthrene. Colony forming units were used to monitor parent strain UG14r and gfp-marked UG14Gr in creosote-contaminated soil at 22 degrees C. Green fluorescence in the gfp-marked colonies allowed detection of UG14Gr, on antibiotic-amended and non-amended Trypticase soy agar (TSA), up to 13 months after inoculation into soil while the parent UG14r strain could be detected, on TSA amended with rifampicin, for only up to 25 days after inoculation into soil. Our studies indicated that the gfp marker can be used for survival studies of marked bacterial cells in contaminated soil. When the gfp-marked UG14Gr strain was co-inoculated with a lux-lac-marked Pseudomonas aeruginosa UG2Lr strain, both strains were unambiguously detected by their respective markers. Comparison of the effect of water holding capacity (WHC) of soil on [C-14]phenanthrene mineralization showed that mineralization proceeded faster in treatments at 60% WHC than at 85% WHC, Nitrogen amendment in soils had no effect on [C-14]phenanthrene mineralization at 60% WHC while treatments at 85% WHC showed higher mineralization in unamended soils than in N-amended soils. (C) 1998 Published by Elsevier Science B.V. All rights reserved.

    ELSEVIER SCIENCE BV, Jul. 1998, FEMS MICROBIOLOGY ECOLOGY, 26 (3), 181 - 191, English

    [Refereed]

    Scientific journal

  • H Maki, H Okamura, Aoyama, I, M Fujita

    We simulated the formation of halogenated by-products of biodegradation products of a nonionic surfactant, nonylphenol ethoxylate (NPE), and evaluated the toxicity of these by-products. Most NPE derivatives bearing shortened ethylene oxide (EO) chains (abbreviated as NPnEO) and nonylphenol carboxylate (NPnEC) disappeared within 24 h. In both NPnEO and NPnEC, benzene rings are substituted by monobromine. In contrast, chlorine-substituted derivatives were scarcely detected. However, the stoichiometrical bromination of NPnEO and NPnEC was not found. Total amounts of NPnEO, NPnEC, and their bromine-substituted products (BrNPnEO and BrNPnEC, respectively) tended to diminish with increasing level of residual chlorine concentration. Hence, it was suggested that both NPnEO and NPnEC were transformed to unknown by-products. The optimum pH for the formation of both BrNPnEO and BrNPnEC was approximately 7, and these formations decreased remarkably at higher pH. The formation of both BrNPnEO and BrNPnEC was shown to be dependent on the bromide anion concentration but independent of the level of residual chlorine. In the umu assay, a mutagenicity test that uses genetically engineered Salmonella bacteria, neither BrNPnEO nor BrNPnEC showed significant mutagenicity irrespective of metabolic activation by S9-mix. However, both BrNPnEO and BrNPnEC showed higher acute toxicity to Daphnia magna than their nonbrominated precursors, NPnEO and NPnEC. The toxicity of BrNPnEO to Daphnia was higher than that of BrNPnEC.

    SETAC PRESS, Apr. 1998, ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 17 (4), 650 - 654, English

    [Refereed]

    Scientific journal

  • 岡村 秀雄, 青山 勲, 羅 栄, Liu, D, Persoone, G

    1998, 環境毒性学会誌, 1 (1), 43 - 50, Japanese

    [Refereed]

    Scientific journal

  • 青山 勳, 岡村 秀雄, 羅 栄, Liu, D, Persoone, G

    1998, 環境技術, 27 (5), 330 - 334, Japanese

    [Refereed]

    Scientific journal

  • 羅 栄, 青山 勳, 岡村 秀雄

    1998, 水環境学会誌, 21 (4), 244 - 249, Japanese

    [Refereed]

    Scientific journal

  • D Liu, RJ Maguire, YL Lau, GJ Pacepavicius, H Okamura, Aoyama, I

    A laboratory experiment was performed to study the role of microorganisms in producing the non-extractable residues by anaerobically incubating cyanazine (2-[[4-chloro-6-(ethylamino)-1,3,5,-triazin-2-yl]-amino]-2-methoxy-1-methylethyl)acetamide] and metolachlor [2-chloro-N-(2-ethyl-6-methoxy-1-methylethyl)acetamide] in culture media that had been inoculated with sewage bacteria from anaerobic sludge. Based on the gas chromatographic analyses of extracts from the degradation, adsorption, and abiotic controls for the parent herbicide and its possible metabolites, this study provided the first direct evidence that bacterial biomass, rather than metabolism, was mainly involved in the formation of bound residues with cyanazine. Anaerobic bacteria appeared to be incapable of forming bound residues with metolachlor. The common phenomenon of age-dependent extractability for bound residues was observed with cyanazine. These results imply that bacteria may adsorb pesticides selectively with preference for certain chemical structures over others.

    TAYLOR & FRANCIS INC, 1998, JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART B-PESTICIDES FOOD CONTAMINANTS AND AGRICULTURAL WASTES, 33 (1), 1 - 15, English

    [Refereed]

    Scientific journal

  • D Liu, RJ Maguire, YL Lau, GJ Pacepavicius, H Okamura, Aoyama, I

    Irgarol 1051, 2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine, is a newly developed herbicidal additive for use in copper-based antifouling paints. It is intended to replace the antifouling agent tributyltin, which has been regulated internationally due to its severe impact on the aquatic ecosystem. However, there is no information in the open literature on the persistence and degradation of Irgarol, a fact that hinders the assessment of its ultimate impact on the environment. This study showed that the white rot fungus Phanerochaete chrysosporium was capable of biotransforming Irgarol 1051. It appears that the metabolism of Irgarol by the fungus proceeds mainly via partial N-dealkylation. Metabolic dealkylation occurs at the cyclopropylamino group resulting in metabolite M1, which has tentatively been identified as 2-methylthio-4-tert-butylamino-6-amino-s-triazine. M1 appeared to be a stable and/or terminal metabolite. No evidence of the heterocyclic ring cleavage of Irgarol 1051 was observed, thus implying a possibility of its degradation product(s) accumulating in the environment. (C) 1997 Elsevier Science Ltd.

    PERGAMON-ELSEVIER SCIENCE LTD, Sep. 1997, WATER RESEARCH, 31 (9), 2363 - 2369, English

    [Refereed]

    Scientific journal

  • 青山 勳, 羅 栄, Hideo Okamura

    1997, 環境技術, 26 (4), 255 - 259, Japanese

    [Refereed]

    Scientific journal

  • G Pacepavicius, YL Lau, D Liu, H Okamura, Aoyama, I

    JOHN WILEY & SONS INC, Feb. 1997, ENVIRONMENTAL TOXICOLOGY AND WATER QUALITY, 12 (1), 97 - 100, English

    [Refereed]

    Scientific journal

  • D Liu, Aoyama, I, H Okamura, BJ Dutka

    Organic solvents are commonly used in many sediment toxicity bioassays to facilitate the extraction and concentration of adsorbed contaminants from sediment samples. However, the inherent biotoxicity of most solvents to the bioassay organism may complicate greatly the interpretation of the toxicity test results. To alleviate this problem, a solvent-less extraction procedure was developed for use in the assessment of sediment toxicity. Basically, it involves the use of sonication and sodium ligninsulfonate to enhance the release of the adsorbed contaminants from the sediment. The procedure was applied to sediment samples collected from the St. Clair River at a site approximately 25 m offshore of Dow Chemicals (Sarnia, Ontario). Test results indicate that the most toxic components of the St. Clair River system near Dow Chemicals were associated mainly with the sediment fraction, and there appeared to be very little or no biotoxicity in the overlaying water column. Several of the major contaminants were identified as chlorinated hydrocarbons. The impact of these chemicals on the aquatic environment is discussed. (C) 1996 by John Wiley & Sons, Inc.

    JOHN WILEY & SONS INC, Aug. 1996, ENVIRONMENTAL TOXICOLOGY AND WATER QUALITY, 11 (3), 195 - 203, English

    [Refereed]

    Scientific journal

  • H Okamura, R Luo, Aoyama, I, D Liu

    To reduce the impact of chemical substances on the aquatic ecosystem, it is essential to understand their ecotoxicological properties in the natural aquatic environment. Consequently, we conducted an ecotoxicological study on the aquatic environment around Lake Kojima, a man-made lake located in the southwest of Japan. Lake Kojima receives its chemical inputs mainly from two rivers that flow through various agricultural and industrial areas. For ecotoxicity screening, surface water and sediment samples were collected 4 times in 1993 from 16 preselected sites, Then, the solutes in the filtered surface water were concentrated by ODS resin, and the organic chemicals in the suspended solids (SS) and sediments were extracted by acetone. A battery of five ecotoxicity tests (agar plate test using bacteria and yeast, algal growth inhibition test, Daphnia magna immobilization test, and root elongation test using lettuce seeds) was used to assess these extracts. The results show that the surface water extracts had a lethal effect on D. magna, the SS extracts suppressed algal growth, and the sediment extracts were inhibitory to the growth of yeast. A significant inhibitory effect by the sediment extracts from 4 lake sites and 3 river sites was detected by these ecotoxicity tests. Attempts also were made to identify the putative ecotoxic chemicals in the collected samples. Elementary sulfur was identified as one of the major toxicants in the sediment extracts that were inhibitory to the yeast growth. Moreover, samples of surface water around Lake Kojima, collected weekly from June to September in 1994, were found to contain three pesticides and were toxic to D. magna, But the concentration of the pesticides detected was too low to cause daphnia immobilization. It is believed that the toxicity of the water extracts was mainly due to the combined toxic effect of natural and man-made components. (C) 1996 by John Wiley & Sons, Inc.

    JOHN WILEY & SONS INC, Aug. 1996, ENVIRONMENTAL TOXICOLOGY AND WATER QUALITY, 11 (3), 213 - 221, English

    [Refereed]

    Scientific journal

  • GJ Pacepavicius, D Liu, RJ Maguire, H Ng, JD Gaynor, H Okamura, Aoyama, I

    Cyanazine (2-[[4-chloro-6-(ethylamino)-1,3,5,-triazin-2-yl]-amino]-2-methylpropanenitrile) is an important selective herbicide used for the control of several annual grassy weeds and certain broad-leafed weeds in fields of corn, soybeans, and triazine-resistant canola. It is one of the most heavily used agricultural herbicides in Ontario. There is, however, very little information in the open literature on the aquatic fate and persistence of cyanazine, a fact that hinders the assessment of its ultimate impact on the aquatic ecosystem. This research showed that cyanazine was very stable in natural surface runoff and soil leachate. It was also very resistant to microbial degradation in water under both aerobic and anaerobic conditions. No apparent biodegradation or biotransformation of cyanazine was observed in a test using mixed cocktails of farmland runoff and soil leachate after an incubation period of 98 days. Its biological persistence was further demonstrated by a cyclone fermenter study in which cyanazine was found to be totally immune to the biodegradation potential of a polynuclear aromatic hydrocarbon degrading bacterial culture and sewage microorganisms after an incubation period of 110-195 days. Using the herbicide metolachlor as a biodegradability reference compound and the white rot fungus Phanerochaete chrysosporium as the test organism, cyanazine was estimated to have a persistence in water much greater than that of metolachlor. Thus, the extensive herbicidal use of cyanazine may have a long-lasting impact on Canadian aquatic ecosystems. (C) 1996 by John Wiley & Sons, Inc.

    JOHN WILEY & SONS INC, Feb. 1996, ENVIRONMENTAL TOXICOLOGY AND WATER QUALITY, 11 (1), 27 - 36, English

    [Refereed]

    Scientific journal

  • Hideo Okamura, 大森 元子, 羅 栄, 青山 勲

    1996, 環境技術, 25 (3), 145 - 148, Japanese

    [Refereed]

    Scientific journal

  • Hideo Okamura, 羅 栄, 青山 勲

    1995, 環境技術, 24 (4), 196 - 202, Japanese

    [Refereed]

    Scientific journal

  • D LIU, RJ MAGUIRE, GJ PACEPAVICIUS, AOYAMA, I, H OKAMURA

    Metolachlor is an important selective herbicide used for the control of several annual grassy weeds and certain broad-leafed weeds in corn, soybean, peanut, and other crops. It is the most heavily used agricultural pesticide in Ontario. There is, however, very little information in the open literature on the aquatic fate and persistence of metolachlor, a fact that hinders the assessment of its ultimate impact on the aquatic ecosystem. This study showed that metolachlor was very stable in natural water systems. No apparent biodegradation or biotransformation of metolachlor was observed in three test lake waters after an incubation period of 170 days. With a polynuclear aromatic hydrocarbon (PAH) degrading bacterial culture as the test organism, metolachlor was estimated to have an environmental persistence much greater than medium molecular weight PAHs. Thus the extensive herbicidal use of metolachlor may have a long-lasting impact on Canadian aquatic ecosystems. The white rot fungus Phanerochaete chrysosporium was able to biotransform metolachlor. Based on the three identified metabolites, a tentative metabolic pathway of metolachlor biotransformation by P. chrysosporium was proposed, involving demethylation, hydroxylation, and hydrolytic dechlorination. (C) 1995 by John Wiley & Sons, Inc.

    JOHN WILEY & SONS INC, Nov. 1995, ENVIRONMENTAL TOXICOLOGY AND WATER QUALITY, 10 (4), 249 - 258, English

    [Refereed]

    Scientific journal

  • Ecotoxicity assessment of agricultural effluent and surface water during the application of paddy pesticides.

    Okamura, H, Luo, R, Omori, M, Mitsui, T, Aoyama, I, Liu, D

    1995, Proceeding of 6th International Conference on the Conservation and Management of Lakes -Kasumgaura '95, 1195-1198

    [Refereed]

    International conference proceedings

  • H OKAMURA, AOYAMA, I

    Assessing the interactive toxic effect of chemicals in the environment is becoming a matter of increasing public focus on and concern with ecotoxicological aspects. The purpose of this study is to find the relationship between an interactive toxic effect and distribution of heavy metals in algal cells. The green alga Chlorella ellipsoidea Gernec(IAMC-27) was cultured for 6 days in the presence of cadmium and/or chromium. Algal cells were divided into 4 fractions by centrifugation after the cells were disrupted using a French press. The amounts of the metals in each fraction were determined. The interaction effect between the two metals on algal growth was investigated. The amount of one metal taken up in the cells and the growth inhibition rate increased with the concentration of metals in the medium. The amount of one metal in the cells was increased due to the presence of the other metal. Accordingly, the growth inhibition rate also increased. The amounts of Cd accumulated in the soluble fraction and in the membrane fraction of algal cells were 50 and 20%, respectively, of the total amount in the cells. The presence of Cr changed the Cd concentration in both fractions to 40%. The amount of Cr accumulated in each fraction was almost the same in the absence of Cd. The amount of Cr accumulated in the cell wall fraction rose to 90% after 3 days of exposure and it stayed as high as 50% even at the end of the six-day study period in the presence of Cd. It was assumed that the presence of one metal influenced the distribution of the other metal in the cells, which resulted in the synergistic toxic effect. (C), 1994 by John Wiley & Sons, Inc.

    JOHN WILEY & SONS INC, Feb. 1994, ENVIRONMENTAL TOXICOLOGY AND WATER QUALITY, 9 (1), 7 - 15, English

    [Refereed]

    Scientific journal

  • AOYAMA, I, H OKAMURA

    Numerous studies have been conducted on the effects of toxic chemicals using algal batch culture. On the other hand, continuous culture research has the advantage of allowing optimal cell growth. Few studies on the interactive toxic effect between chemicals have been carried out either with batch culture or with continuous culture. The purpose of this study is to find the relationship between interactive toxic effects and the bioconcentration of heavy metals using continuous algal culture. The green alga Chlorella ellipsoidea was used as a test organism. As test substances cadmium and chromium were used. The amount of heavy metals both in algae and in the medium was determined after the cells had been exposed to heavy metals for 10 days. The amount of Cd taken up in the cells and the growth inhibition rates caused by Cd increased as the concentration of Cd in the medium became higher. The inhibition rates rose drastically but the amount of Cd in the cells remained at almost the same level even if Cr was added. The bioconcentration factors of Cd were ca. 10,000 in all the cases tested, regardless of the presence of Cr. The amount of Cr in the cell exposed to Cr was low, while that amount and the growth inhibition rates for all the concentrations tested increased when Cd was added to the medium containing Cr. The bioconcentration factors of Cr reached 156,000 as the concentration of Cd in the medium increased. It seems that the toxicity of Cr was enhanced because the presence of Cd in the medium raised the amount of Cr in the cell. (C) 1993 John Wiley & Sons, Inc.

    JOHN WILEY & SONS INC, Aug. 1993, ENVIRONMENTAL TOXICOLOGY AND WATER QUALITY, 8 (3), 255 - 269, English

    [Refereed]

    Scientific journal

  • H OKAMURA, A MIMURA, Y YAKOU, M NIWANO, Y TAKAHARA

    Antioxidant activity of an extract from Eucalyptus rostrata was the highest among 16 Eucalyptus species tested. From the leaves of Eucalyptus rostrata nine active compounds were isolated: 1,2,6-tri-O-galloyl-beta-D-glucose and tellimagrandin 1 as tannins; spiraeoside, hyperoside, isoquercitrin, and myricetin 3-O-alpha-L-arabinopyranoside as flavonol glycosides; quercetin 3-O-alpha-arabinopyranoside-2''-gallate, kaempferol 3-O-a-arabinopyranoside-2''-gallate, quercetin 4'-O-beta-D-glucopyranoside-6''-gallate as acylated flavonol glycosides. Antioxidant activity of the tannins and acylated flavonol glycosides, all with galloyl groups, was much higher than that of a synthetic antioxidant. Two of the compounds, spiraeoside and quercetin 4'-glucosylgallate, showed high superoxide dismutase activity.

    PERGAMON-ELSEVIER SCIENCE LTD, Jun. 1993, PHYTOCHEMISTRY, 33 (3), 557 - 561, English

    [Refereed]

    Scientific journal

  • H OKAMURA, A MIMURA, M NIWANO, Y TAKAHARA, H YASUDA, H YOSHIDA

    From the leaves of Eucalyptus rostrata, two new acylated flavonol glycosides were isolated together with quercetin 3-0-alpha-arabinopyranoside-2''-gallate and quercetin 4'-O-beta-D-glucopyranoside. The structures of the new compounds were identified as quercetin 4'-O-beta-D-glucopyranoside-6''-gallate and kaempferol 3-O-alpha-arabinopyranoside-2''-gallate.

    PERGAMON-ELSEVIER SCIENCE LTD, May 1993, PHYTOCHEMISTRY, 33 (2), 512 - 514, English

    [Refereed]

    Scientific journal

  • Hideo Okamura, 青山 勲, 八木 正一

    1989, 水質汚濁研究., 12(10): 654-663, Japanese

    [Refereed]

    Scientific journal

  • Aoyama, I, Okamura, H, Yagi, M

    1989, Toxicity Assessment., 2 (3), 341 - 355

    [Refereed]

    Scientific journal

  • Satoshi Asaoka, Yoshiaki Kiso, Tsubasa Oomori, Hideo Okamura, Toshiro Yamada, Masahiro Nagai

    Phosphorous monitoring is important for eutrophication control in aquatic ecosystems, but ultratrace level concentrations may not be detected by conventional analytical methods. A method for measuring ultratrace level phosphate by online solid-phase extraction combined with HPLC was developed. A short column (50 mm) packed with octadecylsilane (ODS) was used for extraction of phosphoantimonylmolybdenum blue and dodecyltrimethylammonium hydrophobic ion-pair complexes. The ion-pair complexes entrapped on the ODS column were eluted with CH3CN/H2O (35/65; flow rate, 1.0 ml min(-1)) and monitored by an ultraviolet/visible spectrophotometer (lambda = 872 nm). Phosphate concentration was determined from the peak area of the ion pair. The limit of detection for orthophosphate was 0.15 mu g PO4 l(-1) and the dynamic range was 0.15-100 mu g PO4 l(-1). Although our method was susceptible to silicate interference, it could be corrected by a proposed interference correction equation. (C) 2014 Elsevier B. V. All rights reserved.

    ELSEVIER SCIENCE BV, Jul. 2014, CHEMICAL GEOLOGY, 380, 41 - 47, English

    [Refereed]

    Scientific journal

  • Satoshi Asaoka, Yoshiaki Kiso, Masahiro Nagai, Hideo Okamura

    The concentration of phosphate in surface and oligotrophic waters is sometimes below the detection limit of conventional analytical methods. In this work, a membrane extraction method using a hydrophilic PTFE (H-PTFE) membrane filter was developed to detect trace level phosphate. Phosphoantimonyl-molybdenum blue (PAMB) was prepared under conventional conditions. The PAMB was made to react with hexadecyltrimethyl ammonium (HTMA) ions by ultrasonication in an ice bath to form an ion pair of PAMB and HTMA. The ion pair was entrapped on a H-PTFE filter by filtration, and the ion pair on the filter was extracted with CH3CN. When 10 mL of CH3CN was used as the extraction solvent for 100 mL of water sample (10 times of concentration factor), 0.80 mu g PO4 L-1 (0.26 mu g P L-1) was successfully detected using a conventional spectrophotometer equipped with a 5 cm cell. The total phosphorus could also be detected after oxidation with potassium peroxosulfate.

    ROYAL SOC CHEMISTRY, 2015, ANALYTICAL METHODS, 7 (21), 9268 - 9273, English

    [Refereed]

    Scientific journal

  • Toxicity testing in Japan and the use of Toxkit microbiotests

    Aoyama, I, H Okamura, L Rong

    Management of toxic chemicals in the aquatic environment is performed in Japan by setting environmental standards by law. Forty-nine chemicals are regulated and measured once a month at specific sites in rivers and lakes. Many of these chemicals are detected at various places in Japan, but in concentrations below the standard values. Dioxins, which are not regulated, have been detected in leachates from a landfill area of industrial wastes and also in human mother milk. In Japan, bioassays are not used to date as a monitoring tool. However, a manual of ecotoxicological test methods for chemicals is presently under examination by the Ministry of international Trade Industry, the Ministry of Agriculture, Forestry and Fisheries and the Environmental Agency. In most cases, the methods proposed are in accordance with OECD Guidelines for the testing of chemicals; they comprise algal, Daphnia and fish tests. Many toxicity test methods have already been described in Japanese scientific literature, based on various types of test organisms from different phylogenetic groups such as e.g. bacteria, yeasts, protozoans, micro- and macro-algae, crustaceans, molluscs, insects, amphibians, fish and birds. Taking into account the difficulties associated with the culturing and/or maintenance of live stocks, the "culture free" Toxkit microbiotest technology appeared appealing to the authors and is now used for environmental monitoring purposes in their laboratory. A new toxicity testing method using mobility analysis of Daphnias obtained from ephippia has recently been developed and will be reported. The test criterion is the change in mobility of Daphnia neonates, which is measured by computer analysis of videocamera-pictures (0.013 sec) during 5 seconds. The mobility per time unit is calculated subsequently. Toxicity is evaluated by comparing the change in mobility of Daphnias exposed to chemicals, versus that in the controls. The technology allows to detect the increase in mobility by stimulus at low concentration and the decrease at higher concentrations of toxicants. The method has a high sensitivity and allows for toxicity detection in less than 3 hours. Results with the new mobility analysis method with Daphnia neonates will be compared with those obtained with the conventional Daphnia method prescribed by the OECD.

    KLUWER ACADEMIC/PLENUM PUBL, 2000, NEW MICROBIOTESTS FOR ROUTINE TOXICITY SCREENING AND BIOMONITORING, 123 - 133, English

    [Refereed]

    International conference proceedings

  • Toxicity assessment of water environment using biomonitoring

    H Okamura, Aoyama, I

    PESTICIDE SCI SOC JAPAN, 1998, JOURNAL OF PESTICIDE SCIENCE, 23 (2), 166 - 173, Japanese

    [Refereed]

    Scientific journal

  • Development of Simultaneous Determination Method of Hydroxylated Polycyclic Aromatic Hydrocarbons in Urine by LC/MS/MS and Its Application to Assessment of Polycyclic Aromatic Hydrocarbons Exposure

    Tetsuya Hirai, Hiroaki Kinoshita, Hideo Okamura, Yoshiji Yano, Takeshi Nakano

    Polycyclic aromatic hydrocarbons (PAHs) are a group of chemicals released into the air during the incomplete burning of fossil fuels, such as gasoline and other organic substances. Some PAHs are reasonably anticipated to be human carcinogens. In this study, a high-performance liquid chromatography-tandem mass-spectrometry method has been developed for the simultaneous quantification of eight urinary OH-PAHs, including 1-hydroxynaphthalene (1-OH-Nap), 2-hydroxynaphthalene (2-OH-Nap), 1-hydroxyphenanthrene (1-OH-Phe), 2-hydroxyphenanthrene (2-OH-Phe), 3-hydroxyphenanthrene (3-OH-Phe), 4-hydroxyphenanthrene (4-OH-Phe), 9-hydroxyphenanthrene (9-OH-Phe) and 1-hydroxypyrene (1-OH-Pyr) in human urine. Deuterated 3-OH-Phe-d(9) and 1-OH-Pyr-d(9) were used for quantification of the analyte as an internal standard. Considerable amounts of PAHs are present in the workplace. PAHs exposure is reported to exist high in coke plants, aluminium work and paving work. In order to assess the potential health risks posed by exhaust gas from ships, and to obtain a better understanding of the occupational hazards connected with PAHs exposure, the concentration of OH-PAHs in urine collected from mariners has been analyzed. This method was applied to the analysis of OH-PAHs in 29 urine specimens collected from the crews on a ship. The median concentrations of urinary 1-OH-Nap, 2-OH-Nap, 1-/9-OH-Phe, 2-OH-Phe, 3-OH-Phe, 4-OH-Phe and 1-OH-Pyr were 0.36, 0.57, 0.12, 0.07, 0.14, 0.07 and 0.11 mu g/g creatinine in the crews, respectively. The developed method was applied to occupational exposure to urine in order to assess human exposure due to the working environment.

    JAPAN SOC ANALYTICAL CHEMISTRY, Nov. 2012, BUNSEKI KAGAKU, 61 (11), 925 - 930, Japanese

    [Refereed]

    Scientific journal

  • Survey for the occurrence of the new antifouling compound Irgarol 1051 in the aquatic environment

    D Liu, GJ Pacepavicius, RJ Maguire, YL Lau, H Okamura, Aoyama, I

    Irgarol 1051, (2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine), is a newly developed herbicidal additive for use in copper-based antifouling paints. It is intended as replacement for the highly toxic antifouling agent tributyltin, which has been regulated internationally. Currently, there is no information in the open literature on its environmental occurrence outside Europe. A two-year survey was conducted in 1996-1997 to investigate the occurrence of Irgarol 1051 in Canadian and Japanese aquatic environments. Six large trade ports (Vancouver, Toronto, Montreal, Halifax, Mizushima and Kobe), 73 marinas and 13 fishery harbors were surveyed. Irgarol 1051 was not detected in the Canadian aquatic environment, but was positively identified in the enclosed coastal waters of the Sere Inland Sea in Japan. Among the six trade ports surveyed, only the Mizushima Port had low levels of Irgarol 1051, up to 19.5 ng/L. Approximately 27% of the marinas surveyed in the Seto Inland Sea were found to have been contaminated by Irgarol 1051, ranging in concentration between 12.5 and 264.2 ng/ L. Irgarol 1051 was found more frequently in fishery harbors than in marinas, indicating that besides marinas and trade ports, fishery harbors can also be a significant source of contamination for the aquatic environment. Survey for Irgarol 1051 in the fishery harbors has not been reported before, and it is suggested that fishery harbors, in addition to ports and marinas, should be included in the survey list during the Irgarol 1051 monitoring study. Irgarol 1051 has been reported to be highly toxic to nontarget marine algae with the observable growth inhibition at a concentration as low as 50 ng/L, which is well within the ambient concentration levels found in some localities of the Seto Inland Sea. (C) 1999 Elsevier Science Ltd. All rights reserved.

    PERGAMON-ELSEVIER SCIENCE LTD, Aug. 1999, WATER RESEARCH, 33 (12), 2833 - 2843, English

    [Refereed]

    Scientific journal

  • Higher Bioavailability and Contamination by Copper in the Edible Mussels, Snails and Horseshoe Crabs at Kampung Pasir Puteh: Evidence of an Industrial Effluent Receiving Site at Pasir Gudang Area.

    Chee Kong Yap, Weiyun Chew, Wan Hee Cheng, Hideo Okamura, Hiroya Harino

    2019, Advancements in Bioequivalence and Availability., 2 (5), 1 - 8

    [Refereed]

  • Early developmental responses of three sea urchin species to tralopyril and its two degradation products.

    Lavtizar,V and Okamura,H

    2019, Chemosphere, 229, 256 - 261

    [Refereed]

MISC

  • 船体付着による水生生物の移動を最小化する対策

    OKAMURA HIDEO

    生物研究社, Aug. 2017, 海洋と生物, 39 (4), 332 - 337, Japanese

    [Invited]

    Introduction scientific journal

  • 海技者の尿中PAH代謝物の分析

    YANO YOSHIJI, HIRAI TETSUYA, OKAMURA HIDEO, NAKANO TAKESHI

    2012, 第21回 環境化学討論会 口頭発表, Japanese

    Lecture materials

  • Determination of hydroxylated polycyclic aromatic hydrocarbons in mariner's urine by high performance liquid chromatography-tandem mass spectrometry

    YANO YOSHIJI, HIRAI TETSUYA, KINOSHITA HIROAKI, OKAMURA HIDEO, NAKANO TAKESHI

    19th IMSC 2012, 2012, 19th IMSC 2012 Poster presentation, English

    Others

  • Hideo Okamura

    2009, Sessile Organisms 26(1): 33-41, 26 (1), 33 - 41, Japanese

    [Refereed]

    Introduction scientific journal

  • Hideo Okamura

    2009, 日本海水学会誌, 63 (5), 307 - 311, Japanese

    [Refereed]

    Introduction scientific journal

  • Hideo Okamura

    2006, 安全工学, 45 (6), 399 - 407, Japanese

    [Refereed]

    Introduction scientific journal

  • 千田 哲也, 高橋 一暢, 張野 宏也, Hideo Okamura

    2006, 日本マリンエンジニアリング学会誌, 41: 561-562, Japanese

    [Refereed]

    Introduction scientific journal

  • 海洋汚染とバイオアッセイ.

    Hideo Okamura

    2006, 水環境学会誌, 29: 433-437, Japanese

    [Refereed]

    Introduction scientific journal

  • Hideo Okamura

    2005, J.Japan Inst.Marine Engineering, 40 (1), 35 - 38, Japanese

    [Refereed]

    Introduction scientific journal

  • Present status of Japanese antifouling systems

    Hirohisa Mieno, Hideo Okamura

    2005, Review of the Faculty of Maritime Sciences, Kobe University, 2: 79-86., Japanese

    Others

  • Environmental fate of antifouling compound Irgarol 1051.

    Hideo Okamura

    2005, Water, 47(3): 37-40., Japanese

    Introduction scientific journal

  • Hideo Okamura

    2004, 日本海水学会誌, 58(4): 361-366, Japanese

    [Refereed]

    Introduction scientific journal

  • 日本海水学会第4回若手の集いを終えて.

    Hideo Okamura

    2004, 日本海水学会誌., 58(4): 334, Japanese

    [Refereed]

    Others

  • 第18回環境科学会セミナー報告.

    信川 貴子, Hideo Okamura

    2004, 環境科学会誌, 17(1): 83-84, Japanese

    [Refereed]

    Others

  • 環境毒性学における単一種試験の適用と解釈に関する指針文書(カナダ環境省出版物Guidance Document on Application and Interpretation of Single-species Tests in Environmental Toxicologyの訳書)

    Hideo Okamura

    2004, Guidance Document on Application and Interpretation of Single-species Tests in Environmental Toxicology, 第3921号, pp.258, Japanese

    [Refereed]

    Others

  • 関口 幹周, 小野 芳朗, 岡村 秀雄

    廃棄物学会, 28 Nov. 2002, 廃棄物学会研究発表会講演論文集, 13 (0), 1185 - 1187, Japanese

  • 日本水環境学会第36回年会総括報告

    Hideo Okamura

    2002, 水環境学会誌, 25(6):310-315, Japanese

    [Refereed]

    Others

  • 化学物質の生態系影響評価試験の開発動向 -試験キットを用いた毒性試験法とその適用-.

    Hideo Okamura

    2002, 瀬戸内海区水産研究所 調査研究叢書, 第2号、37-43, Japanese

    [Refereed]

    Introduction scientific journal

  • 有機スズ剤に替わる防汚剤の今.

    Hideo Okamura

    2000, 瀬戸内海., 23: 15-20, Japanese

    [Refereed]

    Introduction scientific journal

  • 第9回毒性評価に関する国際シンポジウムへの参加報告書

    Hideo Okamura

    2000, 昭和シェル石油環境研究助成財団-1998年度助成研究成果報告書, pp.86-87, Japanese

    [Refereed]

    Others

  • 生物活性物質は消えてどこへ行く?.

    Hideo Okamura

    2000, 京都大学環境保全センター「環境保全」, 15: 58-67, Japanese

    [Refereed]

    Introduction scientific journal

  • 水環境の診断ツール -マイクロバイオテスト.

    Hideo Okamura

    2000, 生物工学会誌, 78(3):102, Japanese

    [Refereed]

    Introduction scientific journal

  • バイオレメディエーション研究事例 -クレオソート油汚染土壌浄化への光るタンパク質の利用-.

    Hideo Okamura

    2000, 水, 42(1): 25-29, Japanese

    [Refereed]

    Introduction scientific journal

  • 第8回毒性評価に関する国際シンポジウム後記

    青山 勳, Hideo Okamura, 羅 栄

    1998, 環境毒性学会誌, 1(1): 70-71, Japanese

    [Refereed]

    Others

  • Hideo Okamura, 青山 勲

    1998, 日本農薬学会誌, 23(2): 166-173, Japanese

    [Refereed]

    Introduction scientific journal

Books etc

  • Sediment watch (Ed. Yap,C.K.)

    Yap CK, OKAMURA HIDEO, Harino H

    Joint work, Nova Science Publishers, 2018, English, Managing sustainable coastal environments by sediment watch: A review. Chapter 1, 1-21

    Scholarly book

  • Antagonistic and synergistic effects of antifouling chemicals in mixture

    Shinichi Nagata, Zhou Xiajian, Hideo Okamura

    Joint work, Encyclopedia of ecology, Jun. 2008, English, ISBN: 9780444520333

    Scholarly book

  • 有機スズ代替防汚剤は底質中で無害となるか?

    Hideo Okamura

    Single work, 科学研究費補助金基盤研究B研究成果報告書., 2008, Japanese

    Report

  • 「固体・ガス状試料の安全性評価システムの開発」成果報告書.

    Hideo Okamura

    Joint work, 文部科学省リーディングプロジェクト. 一般・産業廃棄物・バイオマスの複合処理・再資源化プロジェクト., 2008, Japanese

    Report

  • Detoxification of steroidal hormones in the aquatic environment. In Drinking Water

    Nishida T, Okamura H

    Joint work, Nova Publishers, 2008, English

    Scholarly book

  • 廃棄物処分場の有害物質の安全・安心保障、最終成果報告書.

    Hideo Okamura

    Joint work, 文部科学省科学技術振興調整費 重要課題解決型研究., 2007, Japanese

    Report

  • Antifouling Paint Biocides. The Handbook of Environmental Chemistry.

    Hideo Okamuraq, Hirohisa Mieno

    Joint work, Springer, 2006, English

    Scholarly book

  • 環境・健康科学辞典(日本薬学会編)

    Hideo Okamura

    Joint work, 丸善, 2005, Japanese

    Scholarly book

  • 2003年度環境助成研究成果概要集.

    Hideo Okamura

    Joint work, 鉄鋼業環境保全技術開発基金., 2005, Japanese

    Report

  • 平成15年度学術研究支援事業 研究成果報告書.

    Hideo Okamura

    Joint work, 財団法人ひょうご科学技術協会, 2004, Japanese

    Report

  • 「最終処分場管理における化学物質リスクの早期警戒システムの構築」総合研究報告書.

    Hideo Okamura

    Joint work, 環境省廃棄物処理等科学研究費補助金, 2004, Japanese

    Report

  • ソルト・サイエンス研究財団-平成14年度助成研究報告集

    Hideo Okamura

    Joint work, ソルト・サイエンス研究財団, 2004, Japanese

    Report

  • Indicators of Sustainable Development: Assessing Changes in Environmental Conditions

    Heng, L.Y, Mokhtar, M.B, Aoyama, I, Rong, L, Okamura, H

    Joint work, LESTARI, 2004, English

    Scholarly book

  • 水環境における新規防汚剤の運命および生態影響.

    Hideo Okamura

    Single work, 科学研究費補助金基盤研究C2研究成果報告書., 2003, Japanese

    Report

  • 新規船底防汚剤が海産プランクトンに及ぼす影響評価平成14年度クリタ水・環境科学振興財団 研究成果報告書.

    Hideo Okamura

    Joint work, 環境科学振興財団, 2003, Japanese

    Report

  • 滋賀県琵琶湖研究所プロジェクト研究(H9〜12年度)「湖内現象を考慮したノンポイント負荷削減対策の検討」報告書,390-394

    Hideo Okamura

    Joint work, 滋賀県琵琶湖研究所, 2002, Japanese

    Report

  • ソルト・サイエンス研究財団-平成12年度助成研究報告集 2000

    Hideo Okamura, 青山 勳

    Joint work, ソルト・サイエンス研究財団, 2002, Japanese

    Report

  • ソルト・サイエンス研究財団-平成11年度助成研究報告集 1999

    Hideo Okamura, 青山 勳

    Joint work, ソルト・サイエンス研究財団, 2001, Japanese

    Report

  • ソルト・サイエンス研究財団-平成10年度助成研究報告集 1998

    Hideo Okamura, 青山 勳

    Joint work, ソルト・サイエンス研究財団, 2000, Japanese

    Report

  • New Microbiotests for Routine Toxicity Screening and Biomonitoring

    Aoyama, I, Okamura, H, Luo, R

    Joint work, Kluwer Academic/Plenum Publishers, 2000, English

    Scholarly book

  • 両備木聖園記念財団研究報告書

    Hideo Okamura

    Joint work, 両備木聖園記念財団, 1999, Japanese

    Report

  • 住友財団-平成9年度環境研究助成報告書

    Hideo Okamura

    Joint work, 住友財団, 1999, Japanese

    Report

  • 滋賀県琵琶湖研究所所報

    Hideo Okamura, 大久保 卓也, 須戸 幹, 濱田 仁, 今泉 真知子, 市木 敦之, 伏脇 裕一

    Joint work, 滋賀県琵琶湖研究所, 1999, Japanese

    Report

  • Modern Soil Microbiology

    Leung, K.T, Errampalli, D, Cassidy, M, Lee, H, Hall, B, Trevors, J.D, Okamura, H, Bach, H.J

    Joint work, Marcel Dekker Inc., New York, 1997, English

    Textbook

  • 日産科学振興財団研究報告書

    青山 勲, 八木 正一, Hideo Okamura

    Joint work, 日産科学振興財団, 1986, Japanese

    Report

  • Toxicity Screening Procedure Using Bacterial Systems.

    Aoyama, I, Okamura, H

    Joint work, Marcel Dekker Inc., New York, 1984, English

    Scholarly book

Presentations

  • Antifouling compounds in Japan and its environmental risk.

    Okamura,H., Kawai,H.

    PICES2019, Victoria, BC, Canada, 24 Oct. 2019

    [Invited]

    Invited oral presentation

  • ディーゼル機関からのススの変異原性と多環芳香族炭化水素の関係

    速水健斗、楠将史、吉田明輝、今吾一、岡村秀雄、段智久、羽賀雄紀、松村千里.

    第89回マリンエンジニアリング学術講演会, 講演論文集. p.245-246., 03 Oct. 2019

  • 海藻類の増殖に及ぼす防汚剤の有害影響

    岡村秀雄,安田諒子,乾秀之,Vladimir P Beskoski,川井浩史.

    第25回日本環境毒性学会研究発表会, P21, 70,, 26 Sep. 2019

  • 船舶から排出されるPM及びその主要成分の特徴

    中坪良平,松村千里,羽賀雄紀,平木隆年,今吾一,楠将史,吉田明輝,速水健斗,浅川大地,岡村秀雄

    第60回大気環境学会年会, Sep. 2019

  • 航行中の船舶から排出されるPMの成分組成

    中坪良平, 松村千里, 羽賀雄紀, 平木隆年, 今吾一, 楠将史, 吉田明輝, 速水健斗,浅川大地,岡村秀雄.

    第36回エアロゾル科学・技術研究討論会, 06 Sep. 2019

  • 舶用ディーゼル機関からのススの変異原性と多環芳香族炭化水素

    楠将史、吉田明輝、速水健斗、今吾一、岡村秀雄、段智久、羽賀雄紀、松村千里

    第88回マリンエンジニアリング学術講演会講演論文集, Oct. 2018

  • ウニの受精・初期発生に対する船底塗装由来粒子の影響

    加納 研多, 浅岡 聡, OKAMURA HIDEO

    第24回日本環境毒性学会, Sep. 2018, Japanese, Domestic conference

    Oral presentation

  • 沿岸域の汚染を評価するための海藻類増殖阻害試験法の開発

    OKAMURA HIDEO, 安田 諒子, 乾 秀之, 川井 浩史

    平成30年度瀬戸内海研究フォーラムin兵庫, Aug. 2018, Japanese, 63040, Domestic conference

    Poster presentation

  • Embryotoxicity of the antifouling biocide tralopyril on sea urchin Pseudocentrotus depressus.

    Vesna Lavtizar, OKAMURA HIDEO

    27th Symposium on Environmental Chemistry, May 2018, English, Okinawa, International conference

    Oral presentation

  • Distribution of Dissolved Copper in Coastal Surface Seawater of Japan.

    Yingqing Lin, Tokuji Kitano, Masayuki Matsubayashi, Satoshi Asaoka, OKAMURA HIDEO

    The 11th International Symposium on Marine Engineering (ISME2017 Tokyo), Oct. 2017, English, International conference

    Oral presentation

  • 船底防汚剤と海洋汚染

    OKAMURA HIDEO

    第23回日本環境毒性学会研究発表会シンポジウム「海洋汚染」, Sep. 2017, Japanese, 東洋大学, Domestic conference

    [Invited]

    Invited oral presentation

  • 沿岸海水中の溶存態銅のモニタリング及びMarine BLMを用いた有害性評価

    北野徳治, 林穎卿, 松林雅之, 浅岡聡, OKAMURA HIDEO

    日本環境毒性学会, Sep. 2017, Japanese, 東洋大学, Domestic conference

    Oral presentation

  • Distribution of perfluoroalkyl acids from Osaka Bay to coastal waters of Western Japan

    Hideyuki INUI, Katsuya YAMAMOTO, Atsushi YAMAMOTO, Hideo OKAMURA, Mitsuru HAYASHI, Takeshi NAKANO, Chisato MATSUMURA, Keiichi FUKUSHI, Vladimir, p. BESKOSKI

    The 14th International Symposium on Persistent Toxic Substances, Sep. 2017, English, Nagoya(Aaichi), International conference

    Oral presentation

  • Water stability of a new antifouling biocide tralopyril and its toxicity to freshwater algae Pseudokirchneriella subcapitata.

    Vesna Lavtizar, OKAMURA HIDEO

    Pollution Control Congress (PCC) 2017., Jul. 2017, English, Melbourne, Australia, International conference

    Oral presentation

  • 日本沿岸の表層海水中の溶存態ニッケルの分布

    林穎卿, 北野徳治, 松林雅之, OKAMURA HIDEO, 浅岡聡

    日本水環境学会, Mar. 2017, Japanese, 熊本大学, Domestic conference

    Oral presentation

  • The Interactive effect of salts and copper pyrithione on a brine shrimp survival.

    Vesna Lavtizar, Daisuke Kimura, Satoshi Asaoka, OKAMURA HIDEO

    International Conference on Emerging Trends in Environmental Engineering and Control (ICETEEPC) 2017, Mar. 2017, English, Beijing, China, International conference

    Oral presentation

  • 溶出試験による漁網防汚塗料から海水に溶出した銅が海産藻類に及ぼす影響.

    北野徳治, 田中風太, 中村紗矢香, OKAMURA HIDEO, 浅岡聡

    第22回日本環境毒性学会, Sep. 2016, Japanese, 愛媛大学, Domestic conference

    Oral presentation

  • Effects of Exhaust Gas from Diesel Engine using Heavy Fuel Oils with Dimethyl Ether on Aquatic Species

    Yu Shinohara, Takashi Otani, Hisayo Okamoto, Tomohisa Dan, Satoshi Asaoka, Hideo Okamura

    84th Conference on Marine Engineering, Proceedings, pp.155-156, Nov. 2014, Japanese, Shimonoseki city, Kaikyo Messe Shimonoseki, Domestic conference

    Oral presentation

  • 天然海水中でのピリチオン防汚剤と銅イオンが塩水性甲殻類に及ぼす影響

    木村太輔, Guo Xin Li, 仁多一徳, 岡村秀雄, ASAOKA SATOSHI

    日本マリンエンジニアリング学会 海洋環境研究委員会第3回ワークショップ, Sep. 2013, Japanese, 神戸大学, Domestic conference

    Oral presentation

  • Mutagenicity of Diesel Exhaust Particulates from DME Blend Oil

    Hisayo Okamoto, Tomohisa Dan, Hideo Okamura

    83rd Conference on Marine Engineering, Proceedings pp.107-108, Sep. 2013, Japanese, Shizuoka, Japan, Domestic conference

    Oral presentation

  • 閉鎖性水域における環境改善材料のXAFSによる性能評価

    ASAOKA SATOSHI, 岡村秀雄, 与儀千尋, 太田敏明, 片山真祥, 稲田康宏, 早川慎二郎

    立命館大学SRセンター研究成果報告会, Jun. 2013, Japanese, 立命館大学, Domestic conference

    [Invited]

    Invited oral presentation

  • 好気・嫌気環境の繰り返しによる石炭灰造粒物への硫化物イオンの吸着機構の解明

    ASAOKA SATOSHI, 斉藤 直, 岡村秀雄, 早川慎二郎

    第73回分析化学討論会, May 2013, Japanese, 北海道大学, Domestic conference

    Poster presentation

  • 野外水槽を用いた炭酸化製鋼スラグによる閉鎖性水域の底質改善効果の検証

    ASAOKA SATOSHI, 森澤亮介, 曽我浩征, 岡村秀雄, 村上 裕

    第47回日本水環境学会, Mar. 2013, Japanese, 大阪工業大学, Domestic conference

    Oral presentation

  • 炭酸化製鋼スラグを用いた底質改善方法における底生生態系への影響評価

    曽我浩征, 岡村秀雄, ASAOKA SATOSHI, 村上 裕

    第47回日本水環境学会, Mar. 2013, Japanese, 大阪工業大学, Domestic conference

    Oral presentation

  • 炭酸化製鋼スラグの硫化物イオン除去メカニズム

    森澤亮介, ASAOKA SATOSHI, 岡村秀雄, 福士惠一, 村上 裕

    第47回日本水環境学会, Mar. 2013, Japanese, 大阪工業大学, Domestic conference

    Oral presentation

  • Oxidation mechanisms of hydrogen sulfide on the surface of manganese oxside in granulated coal ash

    Satoshi ASAOKA, Shinjiro HAYAKAWA, Hideo OKAMURA, Tadashi SAITO

    17th Hiroshima International Symposium on Synchrotron Radiation, Mar. 2013, English, Hiroshima University, International conference

    Poster presentation

  • 産業系リサイクル材料各種による閉鎖性水域の環境改善効果の比較

    ASAOKA SATOSHI, 岡村秀雄, 山本民次, 早川慎二郎, 竹田一彦, 片山真祥

    日本分析化学会広島地区分析技術講演会, Feb. 2013, Japanese, 広島大学, Domestic conference

    Invited oral presentation

  • Remediation of eutrophic sediments using industrial byproducts

    Satoshi ASAOKA, Tamiji YAMAMOTO, Hideo OKAMURA

    4th IWA Young Water Professional Conference 2012, Dec. 2012, English, Tokyo, International conference

    Oral presentation

  • Toxic Substances Absorbed on Diesel Exhaust Particles from Jatropha Oil

    NAKAMURA Sayoka, ODA Erina, MATSUMOTO Saori, OKAMOTO Hisayo, DAN Tomohisa, OKAMURA Hideo

    82nd Conference on Marine Engineering Proceedings pp.59-60, Sep. 2012, Japanese, 日本マリンエンジニアリング学会/The Japan Institute of Marine Engineering, Takamatsu, Domestic conference

    Oral presentation

  • Nitrated Polycyclic Aromatics Hydroarbons Absorbed on Diesel Exhaust Particulates from Jatropa Oil

    OKAMOTO Hisayo, NAKAMURA Sayoka, MATSUMOTO Saori, DAN Tomohisa, OKAMURA Hideo

    82nd Conference on Marine Engineering Proceedings pp.61-62, Sep. 2012, Japanese, 日本マリンエンジニアリング学会/The Japan Institute of Marine Engineering, Takamatsu, Domestic conference

    Oral presentation

  • Abnormal duckweed fronds occurred by metal pyrithione.

    Okamura H, Togosmaa L

    16th International Congress on Marine Corrosion and Fouling, Jun. 2012, English, Seattle, USA, International conference

    Poster presentation

  • The Addition Effect of DME on Environmental Toxixity of Diesel Exhaust Particulates

    Takuya SAWAMOTO, Hideo OKAMURA, Hirotsugu FUJITA, Tomohisa DAN

    81st Conference on Marine Engineering Proceedings pp.49-50, May 2011, Japanese, 日本マリンエンジニアリング学会, Tokyo, Domestic conference

    Oral presentation

  • 誘導体化HPLC法によるピリチオン化合物の定量

    Hideo Okamura

    第2回ワークショップ「船底塗料と海洋環境に関する最新の話題」, 2011, Japanese, 日本マリンエンジニアリング学会, 千葉工業大学, Domestic conference

    Oral presentation

  • 水環境中におけるトリフェニルボラン防汚剤の運命に及ぼす光の影響

    Ai Tsuboi, Seiji Koyama, Hideo Okamura, Keiichi Fukushi

    第81回マリンエンジニアリング学術講演会, 2011, Japanese, 日本マリンエンジニアリング学会, 東京海洋大学, Domestic conference

    Oral presentation

  • ピリチオン防汚剤がウキクサ葉状体に及ぼす影響

    Hideo Okamura

    第17回日本環境毒性学会, 2011, Japanese, 日本環境毒性学会, 鹿児島大学, Domestic conference

    Oral presentation

  • Mutagenic evaluation of the ship diesel exhaust gas from marine diesel engine

    Takuya SAWAMOTO, Hideo OKAMURA, Hirotsugu FUJITA, Tomohisa DAN

    80th Conference on Marine Engineering Proceedings pp.55-56, Aug. 2010, Japanese, 日本マリンエンジニアリング学会, Niigata (TOKI-Messe), Domestic conference

    Oral presentation

  • 重金属イオンが防汚剤トリフェニルボランピリジン(TPBP)の運命に及ぼす影響

    Hideo Okamura

    日本海水学会第61年会, 2010, Japanese, 日本海水学会第61年会, 石巻専修大学, Domestic conference

    Oral presentation

  • 広島湾北部海域における有機スズ代替化合物汚染とカキに与える影響

    Hideo Okamura

    第80回マリンエンジニアリング学術講演会, 2010, Japanese, 日本マリンエンジニアリング学会, 朱鷺メッセ, Domestic conference

    Oral presentation

  • バイオアッセイによる港湾表層底質の汚染評価

    Hideo Okamura

    第80回マリンエンジニアリング学術講演会, 2010, Japanese, 日本マリンエンジニアリング学会, 朱鷺メッセ, Domestic conference

    Oral presentation

  • 遺伝子マーカーによる船体付着藻類の多様性解析

    川井 浩史, 羽生田 岳昭, 河地 正伸, 岡村 秀雄

    ワークショップ「船底塗料と海洋環境に関する最新の話題」, Nov. 2009, Japanese, 日本マリンエンジニアリング学会, 函館, Domestic conference

    Oral presentation

  • ECOTOXICITY ASSESSMENT OF NEW BIOCIDE-FREE ANTIFOULING PAINTS.

    Hideo Okamura, Kawachi, M, Hanyuda, T, Kawai, H

    14th International Symposium on Toxicity Assessment., Sep. 2009, English, Metz, France, International conference

    Poster presentation

  • 底質コアサンプル中の船底防汚剤分布.

    常政 典貴, 岡村 秀雄, 張野 宏也, 山崎 秀夫

    ワークショップ船底塗料と海洋環境に関する最新の話題講演集., 2009, Japanese, 函館, Domestic conference

    Oral presentation

  • 船舶ディーゼル排ガス由来粒子状物質に吸着した有害化学成分に関する研究.

    沢本 拓也, 岡村 秀雄, 藤田 浩嗣, 河原林 威一郎

    第79回マリンエンジニアリング学術講演会講演論文集. 161-162., 2009, Japanese, メルパルク広島, Domestic conference

    Oral presentation

  • 船底用および漁網用防汚剤の水環境における運命.

    壺井 愛, 井谷 武, 岡村 秀雄

    日本海水学会第60年会講演要旨集. pp.16-17., 2009, Japanese, 東大, Domestic conference

    Oral presentation

  • 水環境におけるトリフェニルボラン防汚剤の生態影響評価.

    Ai Tsuboi, Okamura, H, 常政 典貴

    ワークショップ船底塗料と海洋環境に関する最新の話題講演集., 2009, Japanese, 函館, Domestic conference

    Oral presentation

  • 海産発光細菌を用いた港湾底質の汚染評価.

    高取 紘平, 常政 典貴, 岡村 秀雄

    第79回マリンエンジニアリング学術講演会講演論文集. 163-164., 2009, Japanese, メルパルク広島, Domestic conference

    Oral presentation

  • キャピラリーゾーン電気泳動法によるピリジントリフェニルボラン及び分解生成物の同時定量.

    福士 惠一, 薬師寺 雄樹, 岡村 秀雄, 橋本 陽一, 齋藤 惠逸

    ワークショップ船底塗料と海洋環境に関する最新の話題講演集., 2009, Japanese, 函館, Domestic conference

    Oral presentation

  • カキ発生に与える有機スズ代替船底防汚剤の影響.

    常政 典貴, 岡村 秀雄

    第79回マリンエンジニアリング学術講演会講演論文集. 165-166., 2009, Japanese, メルパルク広島, Domestic conference

    Oral presentation

  • The influence of organotin alternative antifoulants on the oyster's embryology.

    Tsunemasa, N, Okamura, H

    14th International Symposium on Toxicity Assessment.62., 2009, English, Metz, France, International conference

    Poster presentation

  • Fate of triphenylborane-pyridine antifouling agent in sediments (POSTER).

    Hideo Okamura, Kitano, S

    5th SETAC World Congress, Aug. 2008, English, Sydney, Australia, International conference

    Oral presentation

  • Triphenylborane-pyridine antifouling agent degrades by metal ions? (POSTER)

    Tsuboi, A, Hideo Okamura, Harino, H, Tsunemasa, N, Thomas, K, Shim, WJ

    14th International Congress on Marine Corrosion and Fouling., Jul. 2008, English, Kobe, International conference

    Poster presentation

  • Simultaneous determination of pyridine triphenylborane (TPBP) antifouling agent and its estimated degradation products by capillary zone electrophoresis (POSTER).

    Fukushi, K, Yakushiji, Y, Okamura, H, Hashimoto, Y

    14th International Congress on Marine Corrosion and Fouling., Jul. 2008, English, Kobe, International conference

    Oral presentation

  • Contamination of organotin alternative antifoulants in coastal seawater and sediment of Hiroshima Bay (POSTER).

    Tsunemasa, N, Hideo Okamura

    14th International Congress on Marine Corrosion and Fouling., Jul. 2008, English, Kobe, International conference

    Oral presentation

  • 新規防汚剤の環境影響.

    Hideo Okamura

    2008年度日本付着生物学会研究集会, Apr. 2008, Japanese, 東京海洋大学, Domestic conference

    Invited oral presentation

  • 船舶ディーゼル排ガス由来微粒子が動植物プランクトンに及ぼす影響評価.

    河原林 威一郎, Hideo Okamura, 藤田 浩嗣

    日本マリンエンジニアリング学術講演会, 2008, Japanese, Domestic conference

    Oral presentation

  • Ecotoxicity reduction of leachates from model waste columns using permeable reactive barrier (PRB) (POSTER). 119.

    Nishikawa, T, Hideo Okamura, Isogai, T, Ono, Y, Kurata, Y, Watanabe, Y, Mohri, S, Ono, Y

    13th International Symposium on Toxicity Assessment., Aug. 2007, English, Toyama, Domestic conference

    Oral presentation

  • Degradation products of triphenylborane-pyridine antifouling agent in water (ORAL).

    Kitano, S, Hideo Okamura, Toyota, S, Kawarabayashi, I, Harino, H, Thomas, K.V

    13th International Symposium on Toxicity Assessment., Aug. 2007, English, Toyama, Domestic conference

    Oral presentation

  • Consideration of salinity in the evaluation of landfills and solid wastes using aquatic and terrestrial higher plant test (POSTER). 121.

    Mohri, S, Hideo Okamura, Izmo, T, Ono, Y

    13th International Symposium on Toxicity Assessment., Aug. 2007, English, Toyama, Domestic conference

    Oral presentation

  • An evaluation of some PAHs in seawater of the Seto Inland Sea and the Pacific Ocean near west Japan (POSTER). 112.

    Miyanaga, M, Kaneda, K, Hideo Okamura, Yano, Y, Nogami, Y

    13th International Symposium on Toxicity Assessment., Aug. 2007, English, Toyama, Domestic conference

    Oral presentation

  • 「トリブチルスズ代替防汚剤による沿岸域の汚染とバイオアッセイを用いた毒性評価」講演要旨集 9.

    Hideo Okamura

    平成19年度日本水産学会近畿支部シンポジウム-近畿の水環境の現状とその制御に向けて., Jul. 2007, Japanese, 神戸女学院大学, Domestic conference

    Invited oral presentation

  • Protection of Marine Environment. Man-made chemicals used on ship hulls on purpose.

    Hideo Okamura

    2nd Oxford Kobe Institute International Maritime Seminar: Sustainable Maritime Transport., Jun. 2007, English, Kobe Institute, Domestic conference

    Invited oral presentation

  • Acute toxicity of the ash from a gasification test plant on earthworm survival (POSTER).

    Hideo Okamura, Suzuki, K, Mohri, S, Ono, Y

    SETAC Europe 17th Meeting, May 2007, English, Porto, Portugal, International conference

    Oral presentation

  • 瀬戸内海及び太平洋におけるPAHsの濃度レベルのモニタリング第40回日本水環境学会年会講演集.

    兼田 和彦, 宮永 政光, 野上 祐作, Hideo Okamura, 矢野 吉治

    第40回日本水環境学会年会, Mar. 2007, Japanese, 大阪産業大学, Domestic conference

    Oral presentation

  • 浸出水対策のための浸出水の毒性評価

    Hideo Okamura

    平成18年度中国四国地域産業廃棄物処理等技術研修会, Oct. 2006, Japanese, 岡山県生涯学習センター, Domestic conference

    Invited oral presentation

  • 「サンゴと化学物質」「バイオサイドとは?-沿岸域汚染の現状と環境管理」

    Hideo Okamura

    世界自然保護基金ジャパン 講演会, Sep. 2006, Japanese, 環境省国際サンゴ礁研究モニタリングセンター、沖縄県石垣市, Domestic conference

    Invited oral presentation

  • ウキクサ葉状体の異常を指標とした浸出水中の化学物質の影響評価.52. 第12回環境毒性学会講演要旨集.

    西川 嵩紘, 久地井 美央, Hideo Okamura, 毛利 紫乃, 小野 芳朗

    第12回環境毒性学会講演, Sep. 2006, Japanese, 北里大学, Domestic conference

    Oral presentation

  • 水中での硝酸ミコナゾールの光分解性評価(Oral).

    北野 翔太, Hideo Okamura

    日本海水学会第57年会研究技術発表会講演, May 2006, Japanese, 高松, Domestic conference

    Oral presentation

  • 瀬戸内海と太平洋における海水中の多環芳香族炭化水素濃度の比較.

    兼田 和彦, 宮永 政光, 野上 祐作, Hideo Okamura, 矢野 吉治

    第40回日本水環境学会年会, Mar. 2006, Japanese, 仙台, Domestic conference

    Oral presentation

  • Comparison in seawater PAH concentrations taken in Seto Inland Sea and Pacific Ocean

    Kazuhiko Kaneda, Masamitsu Miyanaga, Yusaku Nogami, Hideo Okamura, Yoshiji Yano

    40th Annual Conference on Japan Water Environment, Mar. 2006, Japanese, 宮城県仙台市, Domestic conference

    Oral presentation

  • 高等植物における生長評価エンドポイントの検討.

    毛利 紫乃, 出雲 貴巳, Hideo Okamura, 小野 芳朗

    第40回日本水環境学会年会, Mar. 2006, Japanese, 仙台, Domestic conference

    Oral presentation

  • Investigation of endpoints in grwoth evaluation for higher plant.

    Shino Mohri, Takami Izumo, Hideo Okamura, Yoshiro Ono

    40th Annual Conference on Japan Water Environment, Mar. 2006, Japanese, Sendai, Miyagi, Domestic conference

    Oral presentation

  • The impacts on marine environments by the biocides in ship antifouling paints.

    Zhou, X, Hideo Okamura, Nagata, S

    2nd Asia Pacific International Symposium on Air and Water Treatments by green oxidation/reduction technologies-catalyst plasma and hybrid systems, 2006, English, Dalian, China, International conference

    Oral presentation

  • The impacts on marine environments by the biocides in ship antifouling paints

    Xiaojian Zhou, Hideo Okamura, Shinichi Nagata

    The Progre of Green Oxidation/Reduction Technology, 2006, English, International conference

    Oral presentation

  • Effect of salt concentration on bioluminescence of Vibrio fischeri: Applications on screening for quorum sensing inhibitors

    Zhou Xiaojian, Hideo Okamura, Shinichi Nagata

    Abstracts of International Symposium on Extremophiles and Their Applications, pp. 362, Nov. 2005, English, Tokyo, Japan, International conference

    Poster presentation

  • Single and joint toxicity of some new antifoulants against Vibrio fischeri by bioluminescent assay

    Zhou Xiaojian, Hideo Okamura, Shinichi Nagata

    Abstracts of Pacem In Maribus XXXI Conference, pp. 108, Oct. 2005, English, Queensland, Australia, International conference

    Oral presentation

  • Luminescent bioassay using Vibrio fischeri to assess the pollution of antifoulants

    Zhou Xiang, Hideo Okamura, Shinichi Nagata

    Abstracts of the Conference on Health and Biodiversity 2005, pp. 98, Aug. 2005, English, Galway, Ireland, International conference

    Oral presentation

  • 有機ホウ素系船底防汚剤が水生生物に及ぼす影響(Oral).

    井藤 悠貴, Hideo Okamura, 羽曽部 正豪, 白戸 孝明

    第39回日本水環境学会年会, Mar. 2005, Japanese, 千葉, Domestic conference

    Oral presentation

  • 広島県北部における有機スズ代替船底防汚剤による底質の汚染状況 (Poster).

    常政 典貴, 上野 博昭, 今村 光徳, Hideo Okamura

    第39回日本水環境学会年会, Mar. 2005, Japanese, 千葉, Domestic conference

    Oral presentation

  • Effects of zinc on aquitic macrophyte Lemna minor.

    Hideo Okamura, Mio Kuchii, Takahiro Nishikawa, Shino Mohri, Yoshiro Ono, Masato Yamada

    2005 Conference on Easte Management, 2005, Japanese, Sendai, Miyagi, Domestic conference

    Oral presentation

  • Heavy metals in green mussel and sediments in Otsuchi Bay, Iwate.

    Sayaka Eguchi, Eri Maeda, Mai Miyata, Naoko Takihara, Yoshikazu Yamamoto, Hiroya Harino, Hideo Okamura, Nobuyuki Miyazaki

    Annual Conference on Fishery Science, 2005, Japanese, Kochi, Domestic conference

    Oral presentation

  • Toxicity reduction of metal pyrithiones by near ultraviolet irradiation.

    Hideo Okamura, Kobayashi N, Miyanaga M

    12th International Symposium on Toxicity Assessment, 2005, English, Skiathos, Greece, Domestic conference

    Poster presentation

  • Toxicity assessment of the sediments around dockyards using marine algal test.

    Hirohisa Mieno, Hideo Okamura

    12th International Symposium on Toxicity Assessment, 2005, English, Skiathos, Greece, International conference

    Poster presentation

  • Phytotoxic effects of landfill leachate in Japan.

    Hideo Okamura, Kutchii M, Kose T, Mohri S, Yamada M, Ono Y

    10th International Waste Management and Landfill Symposium, 2005, English, Sardinia, Italy, International conference

    Oral presentation

  • PAHs level in seawater of the Seto Inland Sea and the Pacific Ocean near West Japan.

    Nogami Y, Miyanaga M, Okamura H, Yano Y

    12th International Symposium on Toxicity Assessment, 2005, English, Skiathos, Greece, International conference

    Poster presentation

  • An examination on oxidative decomposition of esterogen like substances using photocatalyst.

    Shimamura J, Miyanaga M, Okamura H, Nogami Y

    12th International Symposium on Toxicity Assessment, 2005, English, Skiathos, Greece, International conference

    Poster presentation

  • Effects of new antifouling biocides on marine plankton.

    Mieno, H, Hideo Okamura

    OCEANS ‘04 MTS/IEEE/TECHNO-OCEAN’04., Nov. 2004, English, Kobe, Domestic conference

    Oral presentation

  • Antibacterial activity of the marine sponge Psammaplysilla purpurea: Importance of its surface-associated bacteria (ORAL).

    Kangasababathy, M, Nagata, K, Fujita, Y, Tamura, T, Hideo Okamura, Nagata, S

    OCEANS ‘04 MTS/IEEE/TECHNO-OCEAN’04., Nov. 2004, English, Kobe, Domestic conference

    Oral presentation

  • 「船舶塗料の水環境に対する影響」

    Hideo Okamura

    中日水環境修復学術研究発表会. トヨタ財団助成国際共同研究 ファイトレメディエーションによる水質浄化, Sep. 2004, Japanese, 無錫市、中国, International conference

    Invited oral presentation

  • 代替船底塗料物質による海域の汚染状況について (Oral).

    常政 典貴, 尾川 健, 今村 光徳, Hideo Okamura

    第13回環境化学討論会, Jul. 2004, Japanese, 静岡県立大学, Domestic conference

    Oral presentation

  • バイオアッセイを用いた代替防汚剤の分解性の評価.

    井藤 悠貴, Hideo Okamura, 羽曽部 正豪, 皆川 敬志

    日本海水学会第55年会研究技術発表会, Jun. 2004, Japanese, 岡山, Domestic conference

    Oral presentation

  • Ecotoxicity of landfill leachates using a battery of bioassay.

    Hideo Okamura, Mohri, S, Yamada, M, Inoue, Y, Mieno, H, Ito, Y, Fujita, A

    SETAC Europe 14th Annual Meeting, Apr. 2004, English, Prague, Czech Republic., International conference

    Oral presentation

  • “新”神戸大学における「海事科学部」と「内海域環境教育研究センター」の連携に関する調査・研究

    SHINICHI NAGATA, OSAMI NISHIDA, Noboru NAKAI, KENJI ISHIDA, Keiichi FUKUSHI, HIROSHI ISHIDA, SHIOTANI SHIGEAKI, KOZAI KATSUTOSHI, YANO YOSHIJI, NISHIO SHIGERU, OKAMURA HIDEO, MIMURA HARUO, MITSURU HAYASHI, Tomohiko IKEUCHI

    神戸大学海事科学部プロジェクト研究報告会, Mar. 2004, Japanese, 神戸, Domestic conference

    Oral presentation

  • 代替防汚剤の環境影響評価

    岡村 秀雄

    日本マリンエンジニアリング学会船底防汚塗料研究委員会 第3回研究会講演要旨集pp.1-4, 2004, Japanese, 日本マリンエンジニアリング学会 船底防汚塗料研究委員会, 未記入, Domestic conference

    Invited oral presentation

  • 瀬戸内海と太平洋における海水中の多環芳香族炭化水素濃度レベルについて

    織田 昌利, 宮永 政光, 野上 祐作, 岡村 秀雄

    第38回日本水環境学会年会講演集 pp.33, 2004, Japanese, 日本水環境学会, 札幌コンベンションセンター, Domestic conference

    Oral presentation

  • 海産動植物プランクトンに及ぼす新規防汚剤の影響評価

    三重野 紘央, 岡村 秀雄, 井藤 悠貴, 藤田 あい

    第38回日本水環境学会年会講演集 pp.92, 2004, Japanese, 日本水環境学会, 札幌コンベンションセンター, Domestic conference

    Others

  • Photosensitized degradation of Irgarol 1051 in water

    OKAMURA Hideo

    Proceedings in International Symposium on Antifouling Paint and Marine Environment, 2004, English, 未記入, 未記入, International conference

    Oral presentation

  • 船底防汚塗料バイオサイドによる沿岸域汚染

    岡村 秀雄

    第6回日本水環境学会シンポジウム講演集p.225, Sep. 2003, Japanese, 日本水環境学会・身近な生活環境研究委員会, 神戸女学院大学, Domestic conference

    Oral presentation

  • 新規防汚剤の生態影響

    岡村 秀雄

    平成15年度日本水産学会近畿支部シンポジウム「有機スズ化合物問題その後と新規防汚剤開発の動向」講演集 pp.5, Jul. 2003, Japanese, 日本水産学会近畿支部, 近畿大学農学部, Domestic conference

    Invited oral presentation

  • 船体防汚剤の生態影響研究

    岡村 秀雄

    第18回環境科学会セミナー「化学物質が生態系に及ぼす影響に関する研究展開と国内法制化の動向」講演集 pp.73-87, May 2003, Japanese, 未記入, 神戸商船大学, Domestic conference

    Invited oral presentation

  • 代替船底塗料物質による海域の汚染状況について

    常政 典貴, 尾川 健, 今村 光徳, Hideo Okamura

    第37回日本水環境学会年会講演集. 268., Mar. 2003, Japanese, 熊本県立大学, Domestic conference

    Oral presentation

  • 生態毒性試験

    Hideo Okamura

    「バイオアッセイ実習セミナー」, Mar. 2003, Japanese, 熊本県立大学., Domestic conference

    Invited oral presentation

  • Environmental risk assessment of new antifouling compound.

    Okamura, H

    Second International Workshop on Bioassay of the Marine Environment in the Northwest Pacific Region., Mar. 2003, English, Toyama., Domestic conference

    Invited oral presentation

  • 有機スズ代替防汚剤と沿岸域環境

    岡村 秀雄

    日本海水学会海水のフロンティア技術シンポジウム講演要旨集 pp.21-24, 2003, Japanese, 日本海水学会西日本支部, 四国電力㈱総合研修所, Domestic conference

    Invited oral presentation

  • 生態毒性試験バッテリーの確立

    岡村 秀雄

    平成14年度環境省廃棄物処理等科学研究費補助金「最終処分場管理におけ化学物質リスクの早期警戒システムの構築」研究報告書 p.8-1~8-13, 2003, Japanese, 未記入, 未記入, Domestic conference

    Others

  • 水環境における新規防汚剤の運命及び生態影響

    岡村 秀雄

    科学研究費補助金助成基盤研究C(2)(課題番号11680530)研究成果報告書 p.98, 2003, Japanese, 未記入, 未記入, Domestic conference

    Others

  • 最終処分場浸出水が動物に及ぼす影響評価

    岡村 秀雄, 藤田 あい, 井藤 悠貴, 三重野 紘央, 毛利 柴乃, 山田 正人, 井上 雄三

    環境科学会2003年会講演論文集 pp.56-57, 2003, Japanese, 環境科学会, 東京大学駒場キャンパス, Domestic conference

    Oral presentation

  • 最終処分場浸出水が植物に及ぼす影響評価

    岡村 秀雄, 井藤 悠貴, 藤田 あい, 三重野 紘央, 毛利 柴乃, 山田 正人, 井上 雄三

    廃棄物学会2003年会講演論文集, 2003, Japanese, 廃棄物学会, 未記入, Domestic conference

    Oral presentation

  • バイオアッセイを活用した新規防汚剤の分解性評価

    岡村 秀雄

    ソルトサイエンス研究財団第15回助成研究発表会要旨集 pp.39, 2003, Japanese, ソルトサイエンス研究財団, 未記入, Domestic conference

    Oral presentation

  • Photosensitized degradation of Irgarol 1051 in freshwater

    OKAMURA Hideo, SUGIYAMA Y

    Proceedings in SETAC Asia/Pacific and ASE 2003, 2003, English, 未記入, 未記入, International conference

    Oral presentation

  • 新規船底防汚剤Irgarol 1051の毒性及びbioavailablity評価.

    関口 幹周, 小野 芳朗, Hideo Okamura

    第13回廃棄物学会研究発表会, Nov. 2002, Japanese, 国立京都国際会館, Domestic conference

    Oral presentation

  • リグニン分解酵素によるIrgarolの分解

    小川 直人, 平井 浩文, 西田 友昭, Hideo Okamura

    第47回リグニン討論会., Oct. 2002, Japanese, アクロス福岡国際会議場, Domestic conference

    Oral presentation

  • ウニ卵を用いた生物検定による汚染原因物質の推定-重金属の場合

    小林 直正, Hideo Okamura

    第36回日本水環境学会年会, 2002, Japanese, 岡山大学, Domestic conference

    Oral presentation

Association Memberships

  • THE JAPAN INSTITUTE OF MARINE ENGINEERING

  • 日本環境科学会

  • 日本腐植物質学会

  • 日本環境化学会

  • 日本環境毒性学会

  • 日本水環境学会

Research Projects

  • 岡村 秀雄, 川井 浩史, 乾 秀之

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kobe University, 01 Apr. 2018 - 31 Mar. 2021, Principal investigator

    Competitive research funding

  • 段 智久, 松村 千里, 岡村 秀雄

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kobe University, 01 Apr. 2017 - 31 Mar. 2020

    本年度は,液化ジメチルエーテル(DME)を連続混合する装置製作の基礎実験として,液化DMEと木タールの混合燃料の流動特性を調べ,既得の加圧型定容容器混合装置を使用して噴霧特性解析及び燃焼特性解析を行なった。 昨年度は木タール単体の流動特性を解析し,その結果,供試木タールの粘度範囲は比較的軽質な重油と同程度であることを得た。今年度は木タールに液化DMEを30wt.%混合した燃料について,密封式のセルに封入した毛細管式粘度計で流動特性を計測した。その結果,木タールの粘度は液化DMEを混合することで大幅に低下し,わずかな過熱でエンジン燃料として使用できる可能性を明らかにした。そこで,この混合割合を条件として連続混合装置の追加設計を行ない,本年度は加圧条件下で攪拌実験装置を使用できる容器部分を製作した。 つぎに液化DME混合木タール燃料の微粒化特性を解析するために,既得の単発燃料噴射装置を使用して,大気雰囲気場における燃料噴霧の拡散状況を調べた。揮発するDMEを可視化するためにシュリーレン光学系を用いて,高速度ビデオカメラによって拡散画像を撮影した。その結果,液化DMEを混合した場合,噴霧周辺に揮発するDMEが広範囲に分散し,噴霧体積が著しく増大するという結果を得た。今後はさらに詳細な噴霧特性の解析を行なっていく予定である。 また液化DME混合時における燃料の燃焼特性について,定容量燃料混合装置を使用して液化DME混合燃料を調製し,予備的な燃焼解析を行なった。木タールに液化DME30wt.%を混合した試験油について,燃焼試験を実施した。エンジン試験の途上,不完全燃焼成分の生成によって運転性能が安定せず,今年度は十分な燃焼解析を行なうことができなかった。今後は吸気温度の高温化,燃料噴射圧力の高圧化などの燃焼改善対策を行なって,燃焼試験を実施していく必要がある。

    Competitive research funding

  • 岡村 秀雄, LAVTIZAR VESNA

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows, Grant-in-Aid for JSPS Fellows, Kobe University, 07 Nov. 2016 - 31 Mar. 2019, Principal investigator

    1、新規防汚剤トラロピリル(TLP)の水中での安定性を評価した。水中のTLPとその主要な分解産物CLを分離定量する方法を、蛍光検出器付HPLCを用いて開発した。人工海水中のTLPの半減期は高水温および高pH条件下でより短く、酸性下では分解しなかった。太陽光近紫外線(UVA)は海水中のTLPの分解に影響しなかったが、天然淡水中でのTLPの分解を促進した。TLPは分解に伴ってCLを生成し、CLはUVA照射によって分解した。 2、水生生物に対してTLPおよび防汚剤の亜鉛ピリチオン(ZnPT)は強い阻害を示したが、TLPの分解産物による阻害は極めて弱かった。藻類増殖に対するTLPの有害性は経時的に減少したことから、TLPは暴露初期に迅速に分解したと考えられた。カキの幼生に対してTLPは強い影響を及ぼした。1時間暴露でのウニ受精率に対するTLPのEC50は、ZnPTに比較して8倍程度であり、48時間暴露後の発生に対するTLPのEC50は、ZnPTの5倍程度であった。このようにウニの受精・発生に対しては、TLPよりもZnPTの方が強い影響を示した。 3、防汚剤の銅ピリチオン(CuPT)の分解産物であるHPTは、銅イオンが存在すると容易にCuPTを生成した。有機物フリーで塩分濃度が高い海水中では、CuPTは塩水性甲殻類に対して強い急性致死影響を示した。CuPTの毒性は供試海水中の有機物濃度、塩分濃度だけでなく、塩類組成によっても有意に影響を受けることを明らかにした。TLPおよびZnPTがそれぞれ銅と共存した場合のウニの受精・発生に対する影響を評価した。1時間暴露でのウニ受精率に対するTLPの毒性に対して、銅は有意な影響を及ぼさなかった。一方、ZnPTの毒性は銅が共存した場合には10倍程度増強し、銅イオンがZnPTと反応してより毒性の強いCuPTを生成したと考えた。

    Competitive research funding

  • OKAMURA Hideo, HARINO Hiroya, DAN Tomohisa, ASAOKA Satoshi

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research, Grant-in-Aid for Challenging Exploratory Research, Kobe University, 01 Apr. 2013 - 31 Mar. 2015, Principal investigator

    The seawater bubbled with exhaust gas emitted from marine diesel engine using a future-generation fuel (new fuel), a 70 % heavy fuel oil with 30% dimethylether, or a traditional heavy fuel oil (C fuel oil) was subjected for ecotoxicity assay and chemical analyses. The seawater bubbled with the gas using C fuel oil indicated higher toxicity on algal growth than that using new fuel. Toxic substances to inhibit algal growth were adsorbed on the particles whose diameter ranging from 0.1 to 1 μm in the seawater. The total amount of polycyclic aromatic hydrocarbons (PAHs) adsorbed on the particles in the seawater bubbled with the gas using new fuel was higher than that using C fuel oil. Carcinogenic PAHs were adsorbed on the particles whose diameter ranging from 0.1 to 1 μm in the seawater bubbled with the gas using C fuel oil, but they were not detected in the seawater with the gas using future-generation fuel.

    Competitive research funding

  • OKAMURA Hideo, DAN Tomohisa, FUJITA Hirotugu, OKAMOTO Hisayo, SAWAMOTO Takuya, MIZUNO Rui, MATSUMOTO Saori

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research, Grant-in-Aid for Challenging Exploratory Research, Kobe University, 2010 - 2012, Principal investigator

    Environmental hazard of the particulate matters (PM) in ship exhaust gas emitted with next generation fuels was evaluated using chemical analyses and ecotoxicity testing. The PM emission, the ecotoxicity, and the mutagenicity of the PM generated from Jatropha oil were lower than the ones from marine diesel oil (MDO: heavy oil A) and heavy fuel oil (HFO: heavy oil C). The PM emission and the ecotoxicity/mutagenicity of the PM generated from the 70 % heavy oils mixed with 30 % dimethyl ether (DME) did not quantitatively decreased in comparison with the ones from MDO or HFO. New compounds produced from heavy oils and DME might explain non-reduction in the toxicity.

    Competitive research funding

  • OKAMURA Hideo, DAN Tomohisa, FUJITA Hirotsugu

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kobe University, 2008 - 2011, Principal investigator

    Biomonitoring procedure using some environmental organisms was applied to assess pollution of port sediments collected at high maritime activity. Some sediments were very toxic to marine photobacteria, which could respond according to the quality of the port sediments. It was, however, difficult to ascertain the observed toxicity with residues of some antifouling compounds and polycyclic aromatic hydrocarbons in the toxic sediments. It was suggested that a wide variety of toxic compounds existed in port sediments.

    Competitive research funding

  • 閉鎖性海域における化学物質の蓄積と海洋生物に与える影響

    岡村 秀雄

    三井物産環境基金, 研究助成, 2008 - 2010, Principal investigator

    Competitive research funding

  • 岡村 秀雄, 藤田 浩嗣, 段 智久

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research, Grant-in-Aid for Challenging Exploratory Research, Kobe University, 2008 - 2009, Principal investigator

    1.船舶排ガス由来粒子状物質(SDEP)中の多環芳香族炭化水素(PAH)およびニトロ化PAH(NPAH)の定量 フォークリフトディーゼルエンジン由来の粒子状物質(標準試料:SRM2975)を供試し、ジクロロメタンを抽出溶媒として高速溶媒抽出装置を用いて有機溶媒可溶画分(SOF)を調製し、アミノプロピルカラムおよびアミノプロピルHPLCカラムを用いた2段階処理の後、15種類のPAHおよび11種類のNPAHをそれぞれ定量する分析方法を確立した。標準試料の他に、(1)A重油を燃料とした本学部練習船の煙突付着スス、(2)C重油を燃料とした実験エンジンIの冷却器内部付着スス、(3)A重油を燃料とした実験用エンジンIIからのSDEP、(4)植物油を燃料とした実験用エンジンIIからのSDEPを供試した。総PAH量が多かったのは、(3)>(4)=(2)>(1)の順であった。分析対象としたNPAHの中で検出されたのは1-nitropyreneのみであり、量が多かった順に(2)>(1)>(4)>(3)であった。 2.SDEPが海洋生態系に及ぼす影響および化学的・毒性学的特性の評価 海産発光細菌に対して、4種類のSOFの中で(1)のみが有意な阻害を示した。一方、Salmonella typhimurium NM2009株を用いた変異原性試験では、試料(1)と(2)が直接変異原性を示し、(2)は間接変異原性も示した。変異原性を示した試料(2)、および(2)から調製したSOFにそれぞれ紫外線UV-Cを8時間照射した。SOFに紫外線を照射して8時間後には全PAHの99.9%が分解したが、変異原性に顕著な減少は認められず、また発光細菌への阻害は逆に強まった。スス粒子そのものに同じ強度の紫外線を8時間照射しても、PHA量、変異原性に顕著な減少は認められなかった。以上のことから、紫外線照射によってSDEPに付着する有機有害成分の生物活性を消去することは困難であると推測された。

    Competitive research funding

  • OKAMURA Hideo

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kobe University, 2004 - 2007, Principal investigator

    Environmental fate of the new antifouling compound, triphenylborane-pyridine (TPBP), was evaluated in terms of its kinetics with sediments and ecotoxicity of its degradation products. Phenol and biphenyl was detected as major degradation products via biodegradation with natural seawater and via photodegradation with near ultra-violet irradiation. TPBP was adsorbed with sediment depending on organic matter contents of sediments and was not desorbed from the sediments. TPBP adsorbed with sediments produced phenol and biphenyl. Ecotoxicity of the two degradation products detected and other putative products such as benzene, diphenylborane, and monophenylborane was much lower than one of TPBP. The fate of TPBP in natural environment was estimated as follows: TPBP released from ship bottom paint is incorporated with suspended solids and finally fall into sediments. TPBP will be partly photodegraded in upper water column but may be less degraded in sediments with less organic matter contents at sea bottom, this may lead possible adverse effects on benthic organisms. A toxicity kit, TOX Screen 2 using Photobacterium leiognathi SB, was applied for sediment toxicity evaluation. Test bacteria was directly exposed to natural sediments using an improved method to interpolate the effects by turbidity and color of sediment on biochemiluminescence. Pollution of the sediment s collected in three bays were quantitatively evaluated with EC50 based on wet weight of sediments. No toxicity was detected in Othuchi Bay, moderate toxicity was detected in some specimen from Maizuru Bay, and high toxicity was bind in several sediments from Osaka Bay. The toxicity was dependent on the organic matter contents of sediments. More research is needed to investigate how the toxicity observed was related with the persistence of antifouling biocides and other toxic chemicals.

    Competitive research funding

  • 太陽光と光触媒を用いたバラスト水の殺菌に関する研究

    岡村 秀雄

    造船学術研究推進機構, 研究助成, 2004 - 2006, Principal investigator

    Competitive research funding

  • 廃棄物処分場の有害物質の安全・安心保障

    岡村 秀雄

    2006, Principal investigator

    Competitive research funding

  • 廃棄物処分場の有害物質の安全・安心保障

    岡村 秀雄

    2005, Principal investigator

    Competitive research funding

  • 石田 廣史

    科学研究費補助金/基盤研究(B), 2005

    Competitive research funding

  • 沿岸域底質の汚染評価

    岡村 秀雄

    鉄鋼業環境保全技術開発基金, 平成15年度一般研究助成, 2003 - 2003, Principal investigator

    Competitive research funding

  • バイオアッセイを活用した沿岸海洋環境の診断

    岡村 秀雄

    ひょうご科学技術協会, 研究助成, 2003 - 2003, Principal investigator

    Competitive research funding

  • 新規船底防汚剤が海産プランクトンに及ぼす影響評価

    岡村 秀雄

    クリタ・水環境科学振興財団, 平成14年度研究助成, 2002 - 2002, Principal investigator

    Competitive research funding

  • バイオアッセイを活用した新規防汚剤の分解性評価

    岡村 秀雄

    ソルト・サイエンス研究財団, 研究助成, 2002 - 2002, Principal investigator

    Competitive research funding

  • Fate and ecotoxicity of new antifouling compounds in aquatic environments.

    OKAMURA Hideo

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), 1999 - 2002, Principal investigator

    The aim of this study was to establish management strategy for the new antifouling compounds alternative to organotins. Compounds used were Irgarol 1051, Diuron, KH 101, Zinc pirithione, Copper Pyrithione, and Sea-Nine 211. Conclusions obtained were as follows : 1) Pollution of Japanese aquatic environment The highest concentrations of three compounds detected in Japanese ambient waters were as follows ; 0.30 μg/L for Irgarol 1051, 1.9 μg/L for M1, and 3.1 μg/L for Diuron. Three-year survey at two stations indicated the concentrations in higher order as Diuron > Irgarol 1051 > M1, generally. 2) Degradation study Mercuric ion could catalyze hydrolysis of Irgarol in water to produce M1. Solar irradiation also degraded Irgarol in water to produce M1. Photodegradation rate of Irgarol was accelerated by natural components in water, suggesting photosensitive degradation with humic substances. The origin of Irgarol, M1, and Diuron detected in water was ascertained to commercial antifouling paints available in Japanese market. 3) Ecotoxicity study Ecotoxicity of Irgarol and M1 was evaluated using environmentally relevant organisms such as marine bacteria, microalgae, seaweed, duckweed, zooplankton, and terrestrial plants. The environmental risk of them was assessed with both the ecotoxicological data and residue concentrations. Toxicity of several new antifouling compounds were evaluated using juvenile fish, suspension-cultured fish cells, fertilized egg of sea urchin, and non-target plant species. The toxicity of metal pyrithiones was high to those species tested, especially zinc pyrithione inhibited sea urchin egg development at femtgram per liter. The metal pyrithiones irradiated with UV-A lamp decreased its toxicity to sea urchin, depending on the duration of light treatment. This suggested that metal pyrithiones could be degraded by solar irradiation.

    Competitive research funding

  • 農薬及びその由来物質によるヒメダカ誘導蛋白をバイオマーカーとする評価系の開発

    小野 芳朗, 岡村 秀雄

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research on Priority Areas (A), Grant-in-Aid for Scientific Research on Priority Areas (A), Okayama University, 2001 - 2001

    新規船底塗料材イルガロール(Irgarol 1051:2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazin)は、我が国で除草剤として使用されているs-triazine系化合物atrazine, simazine, simetrynなどと同じ仲間である。本物質は1993年以降、地中海北部・西部沿岸、イギリス東部・南部沿岸、スイス、スウエーデン、ドイツにおいて、海水、湖水、底質、生物等の環境試料中の残留分析が報告されている。1999年には、瀬戸内海およびオーストラリアの北東部沿岸においても残留が報告されたので、イルガロールはヨーロッパだけでなくアジアやオセアニアにおいても、防汚剤として使用されていると考えられる。メダカに誘導されるビテロジェニンに関しての評価を適用した。濃度0.1mg/Lのイルガロール溶液を0.69mL/minの流速で連続的に流し、ヒメダカ雄成魚15尾を1000mL容ガラス製ビーカー内で飼育しながら14日間曝露した。曝露濃度は、96時間急性毒性試験の結果に基づき決定した。曝露試験は1日16時間の光照射の条件の下で25±1℃の恒温室内で行い、1日1回給餌を行った。曝露期間中、7日目および14日目に採血を行い血清を採取した。この血清を用いて電気泳動した後、全タンパクの非特異的検出を行うCBB染色とヒメダカビテロジェニン抗体による抗原抗体反応を利用したビテロジェニンの特異的検出を行った。特異的検出にはWestern blottingを行った。Western Blottingにメダカ雄に、7日間、14日間でビテロジェニンの誘導がみられた。14日曝露の方がより強く誘導され、ビテロジェニンがイルガロールによって誘導されていることが示された。現在、再現試験を行うと共に、ビテロジェニンの定量を行った。

    Competitive research funding

  • Research for Bio-preventions of Environmental Endocrine Disrupters in Polluted Water by Using Some Useful Plants

    MURAMOTO Shigeki, OKAMURA Hideo, NAKASHIMA Susumu

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Okayama University, 1999 - 2001

    This research was mainly composed next of three subjects. (1) The concentration of some kinds of environmental hormones (agrichemicals, organic chemicals, heavy metals) was investigated at the urban rivers and sea Side. (2) The primary culture experiments on the absorption of environmental hormones by some kinds of plants were carried out in phytotron. The removing of some environmental hormones, benomyl and atrazine was observed by using some kinds of Ocimum basilicum, Var. botorytis, Carchorus calacularis, and Crisanthmum. (3) Also, the plant for used treatment of absorption of environmental hormones from the polluted water is possible as a making materials of the storage bags of crops or papers, especially Carchorus calacuaris and Ciperus alternifolius L. (4) However, the plant absorption of environmental hormones was relatively low compared with those of heavy metals. Future study is needed on the choice of the useful plants for high accumulation of environmental hormones, and the making the protect system for the environmental hormones by planting of many kinds of useful plants inpolluted water area. Also, the research for the chemical composition with the meta-bolite in plants by absorption from the water is a necessary theme.

    Competitive research funding

  • 内分泌撹乱物質の生態毒性評価に関する調査研究

    青山 勲, 藤田 正一, 畠山 成久, 岡村 秀雄, 若林 明子, 田辺 信介

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Okayama University, 2000 - 2000

    有害化学物質による環境汚染は、内分泌攪乱化学物質の存在の発見によって、一層緊急な課題となってきた。このような状況の下で、本研究は世界のエコトキシコロジー研究の動向を把握しつつ、一方では我が国における現状を分析し、内分泌攪乱化学物質による環境汚染及び生態系への影響評価についての研究を行うことを目的とする。また本企画調査研究は、特に内分泌攪乱化学物質を対象として、研究のプライオリティーを明確にしつつ、どのように研究を進めていくべきかを明らかにすることである。このために3つの研究グループを構成した。 第1グループ:バイオアッセイの手法に関する研究 本研究グループは、内分泌攪乱化学物質の生態影響を評価するための個別の手法の問題点課題について検討した。高等動物に対しては様々な方法が提案されているが、生態系に及ぼす毒性評価法はまだきわめて不十分である。まずは内分泌攪乱化学物質が生態系に及ぼす毒性作用の現象そのものにつての知見が必要な段階である。 第2グループ:内分泌攪乱化学物質の環境における運命に関する研究 本研究グループでは、外洋における内分泌攪乱化学物質による影響の実態について、海洋哺乳動物に関するデータの整理を行った。また河川における内分泌攪乱化学物質の動態について、分析化学的な研究を行い、環境資料を濃縮することにより、検出されることが明らかになった。 第3グループ:内分泌攪乱化学物質の生態系に及ぼす総合的な影響評価に関する研究 上述のように、内分泌攪乱化学物質の環境中における存在が、世界の高等動物に現れた異変から認識されるようになったが、内分泌攪乱化学物質の生態系に及ぼす影響そのものをどのように評価するかについての考え方の確立がまず望まれるところである。

    Competitive research funding

  • 水圏生態系における新規防汚剤の究極的運命

    岡村 秀雄

    ソルト・サイエンス研究財団, 研究助成, 2000 - 2000, Principal investigator

    Competitive research funding

  • Study on Fate and Ecotoxicity Evaluation of Hard-decompositive Toxic Chemicals in Ecosystems

    AOYAMA Isao, LUO Rong, OKAMURA Hideo, MURAMOTO Shigeki

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Okayama University, 1998 - 2000

    Pullution of ecosystems by dioxine, agricultural chemicals etc. has become recognized to be an global and very serious issues on a matter of life or death of mankind. The object of this study is to analyze the fate and to evaluate ecotoxicity toxic chemicals released into environments. We clarified the origin of toxic chemicals, the fate of chemicals in an aquatic ecosystem, ecotoxicity, antifouling chemicals in the Inland Sea of Seto and interaction effects of chemicals. At first, we took up the landfill leachate of industrial wastes and evaluated cytotoxicity, genetic toxicity, endocrine disruption. Cytotoxicity for swimming inhibition of Daphnia magna was determined for all sampling cites of leachates. We determined genetic toxicity from a few sampling cites. However, endocrine disrupting effect was determined from 40 fold concentrated leachates of almost all sites. We examined the fate of toxic organic-chemicals along a river in Okayama Prefecture. Hard-dissolved chemicals by water was adsorbed to river sediments and existed more in sediments than in water. Therefore, the toxicity of sediments was stronger than that of water. The quantitative structure-activity relationship analysis was performed for 13 kinds of Chlorophenols using Saccharomyces cerevisiae. The relationships were established between EC50's and a number of molecular proparties. When molecular parameters were used alone, there were high correlations for octanol-water partition coefficient, These results showed that QSAR is a very effective tool in predicting the toxicity of chlorophenols to Saccharomyces cerevisiae as well as to other organisms. Interactive effects among heavy metals and agricultural chemicals, Imidacloprid, were investigated using Daphnia magna. Synergistic and antagonistic effects were observed for heavy metals. Antagonistic and additive effects were observed for Imidacloprid and heavy metals. We could get a high correlation between a traditional swimming inhibition test and a newly developed mobility inhibition test using D. magna. Recently a new antifouling agent Irgarol 1051 has been used. It was found that the Inland Sea of Seto has already been polluted by the new antifouling agent. The decomposed chemicals M1 of irgarol 1051 was also determined in the sea water. The toxicity of the daughter chemicals was weaker than the parent chemicals, but it had hard disintegration. It suggested that the daughter chemicals M1 should be taken care for environmental pollution of sea water in the long run.

    Competitive research funding

  • 海洋生態系における新規防汚剤の運命と生態影響

    岡村 秀雄

    ソルト・サイエンス研究財団, 研究助成, 1999 - 1999, Principal investigator

    Competitive research funding

  • International Comparative Study on Toxicity Assessment

    AOYAMA Isao, HAYATSU Hikoya, LUO Rong, OKAMARA Hideo, NEGISHI Tomoe, ONO Yoshiro

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)., Grant-in-Aid for Scientific Research (A)., Okayama University, 1997 - 1999

    Environmental pollution by hazardous chemicals has been recognized as an international and common matter of life and death of ecosystems and mankind in the world. The methods of management and control of environmental pollution by hazardous chemicals are different depending on each country's way of thinking and circumstances. In our country, at first chemical analyze of chemicals is done and then the concentration of chemicals are compared with environmental standards. While in Europe and U.S.A and Canada, the existing of hazardous chemicals in environments is at first confirmed by bioassays. Many kinds of bioassays are developed and used for environmental management of chemicals. The object of this international co-operative investigation is to contribute to develop the methodology of environmental control and management of chemicals. In the first year of this research project, Japanese scientists visited Australia and China and reported our trend of the methodology of environmental management of Japan and collected the information of environmental management from the two countries. We could not find the special management system in the both countries. We invite a co-operative scientist from Canada and a scientist from Japan side visited Canada, and we carried the co-operative research on the bio-gradiation of chemicals and the bioassay using hydra. In the second year, Japan visited Canada, Czech, Belgium, Switzerland, Austria, China and Taiwan, and scientists from Canada, Switzerland and South Africa were invited to Japan. We discussed about our research project. As for new bioassay method, we developed a high sensitive bioassay method using Daphnia mobility analysis. In the last year, all of co-operative scientists participated in the International Symposium held at South Africa, Pretoria City and presented the research results. We had a group meeting and exchanged views with each other about our research project and discussed how to arrange the report. Research report was published at March.

    Competitive research funding

  • 新規防汚剤とその分解産物が海洋生態系に及ぼす影響評価に関する研究

    岡村 秀雄

    ソルト・サイエンス研究財団, 研究助成, 1998 - 1998, Principal investigator

    Competitive research funding

  • 新規防汚剤による瀬戸内海の汚染評価および生態毒性評価

    岡村 秀雄

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Encouragement of Young Scientists (A), Grant-in-Aid for Encouragement of Young Scientists (A), Okayama University, 1997 - 1998

    1、 瀬戸内海港湾部における海水中のIrgarol 1051 1996年から.1997年にわたり、瀬戸内海沿岸の1府9県におけるマリーナ、漁港、貿易港において採取した海水93試料の内、24試料からIrgarol 1051を検出した。溶存態Irgarol 1051濃度は0〜264ng/Lであり、ヨーロッパで報告されている濃度範囲内にあった。1998年には岡山県南部の2定点で経時的測定を行い、すべての海水試料から本物質を検出した。以上のことから、本物質は主として小型のプレジャーボートおよび漁船用の船底塗料として使用されていると考えられた。ヨーロッパ以外での残留分析はこれが初報である。2、 Irarol 1051の光分解性評 野外実験により、1)水中の本物質は太陽光によって分解し、難分解性の分解産物M1を生成すること、2) 光分解速度は純水中よりも天然水中においてより早く、しかもM1の生成量は天然水中の方がより多いことを明らかにした。紫外線ランプを用いた室内実験によっても、野外実験での観察結果を再現することができた。 3、 Irarol 1051および分解産物の生態毒性評価 1) 分解産物の分離精製:分解産物Mlは異なる3種の分解経路(太陽光分解、木材腐朽菌による生分解、水銀を触媒とした加水分解)によって生成することを明らかにした。そこで、水銀化合物を触媒とした親物質の加水分解反応を利用してMlを大量に生成させ、HPLCを用いて分離精製した。 2) 急性・慢性毒性評価:マイクロバイオテストを活用した生態毒性試験により、分解産物M1の毒性を定量的に評価した。藻類および甲殻類に対するM1の毒性は親物質よりもやや弱かったが、藻類に対する阻害は市販の除草剤の活性に匹敵していた。また、親化合物は高等植物の幼根伸長に対して阻害を示さなかったが、分解産物は強い阻害を示した。

  • 新規防汚剤による瀬戸内海の汚染評価および生態毒性評

    岡村 秀雄

    科学研究費補助金/奨励研究(A), 1997 - 1998, Principal investigator

    Competitive research funding

  • 農業活動が水圏生態系に及ぼす影響評価に関する研究

    岡村 秀雄

    住友財団, 環境研究助成, 1997 - 1997, Principal investigator

    Competitive research funding

  • Developing Research on Monitoring System of Chemicals Using Bioassay

    AOYAMA Isao, RONG Lou, OKAMURA Hideo

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A), Grant-in-Aid for Scientific Research (A), Okayama University, 1995 - 1997

    It is now anxious that environmental pollution by toxic chemicals is concerned with survival of ecosystem and human begins. Under these circumastances, It is now needed that new detecting systems of toxic chemicals in environments with rapidity, easiness and low cost will be done. The object of this study is to detect the toxic chemical in water and in sediments and to know the strength of their toxicity. In this study, microorganisms, Daphnia magna, phytoplankton and yeast and seed of Lettus were used for toxicity testing and relative growth rate, biomass after given time, the length of tag time were evaluated as an end points. Not only 24 hours lethality but also early mobility change of Daphnia were evaluated. The mobility change of Daphnia at early time was newly developed as an end point. This is very sensitive index to know the existence of toxic chemicals in water and this method has a rapidity to detect toxicity. It takes only three hours. We investigated the possibility of monitoring system to detect toxic chemicals in real environment using these bioassays. The environmental water which we took and investigated were river water. lake water and their sediments and land fill leachates of industrial wastes. Our newly developed bioassay, the method of early mobility analysis of Daphnia takes only three hours. This could be reduced very much the bioassay time compared from normal method which is recommended by OECD which takes from 24 or 48 hours. The sensitivity of this method is found that it is very sensitive to chemicals. When Daphnia is exposed to chemicals a low concentrations, the mobility of Daphnia is stimulated and when is at high concentrations, mobility is inhibited. We found that it can be used as an endpoint expressed as TOXICITY UNIT. We took environmental samples (water and sediments) along a river and a lake and performed toxicity testing on them. The seasonal change of toxicity was found and suggested that it reflected the agricultural works. The toxicity of land fill leachate was very strong. Only 3% solution of the leachate was detected to be toxicity for Daphnia mobility tests. Daphnia mobility test and elongation inhibition of lettus seeds were more sensitive than micro organisms. Using these battery tests, we can evaluate the ecotoxicity.

    Competitive research funding

  • 太陽光近紫外線による水田除草剤の光分解

    岡村 秀雄

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Encouragement of Young Scientists (A), Grant-in-Aid for Encouragement of Young Scientists (A), Okayama University, 1995 - 1995, Principal investigator

    水圏環境における農薬の間接光分解に関わる光増感物質の役割を明らかにすることを目的とし、太陽光近紫外線による除草剤の光分解に関する実験を行なった。供試農薬として我が国において使用量の多い代表的な水田除草剤3種類を用いた。各農薬および光増感物質を試験管中の純水に添加し、蛍光ブラックライトからの近紫外線を5日間照射した。esprocarbは直接光分解によってほぼ完全分解したが、dymron,mefenacetの光分解は認められなかった。一方、2%アセトンを加えた場合にはdymronは光分解し、mefenacetの光分解は認められなかった。このようにdymronが間接光分解を生じることが明らかとなったので、以後の実験では供試農薬としてdymronを供試した。 1995年3月から12月まで1ヵ月毎に採水した河川水をそれぞれ凍結乾燥により濃縮し、これにdymronを添加して近紫外線を15日間照射した。光分解は採水時期に関わらず認められ、多くの場合に濃縮河川水で顕著であった。特に4月および5月に採水した河川水における光分解が顕著であった。4月に採取した河川水のpHを4、6、8(pH無調節)、10に調節したところ、dymronの光分解はアルカリ側で顕著に認められた。同じ河川水を加熱処理しても光分解が生じたことから、光増感物質は熱に安定であると考えた。2種類の樹脂(活性炭,イオン交換)をそれぞれ通過させた河川水中では光分解が著しく抑制されたことから、光増感物質はこれらの樹脂に補足されたと考えられた。ゲル瀘渦によって河川水中の光増感物質を分取し、比較的低分子量のピークを有する画分に強い光増感作用を認めた。 このような間接光分解は水圏環境において普遍的に生じていると考えられ、今後はその反応機構を明らかにするために天然光増感物質の同定、さらに農薬の光分解産物に関する情報を得ることが急務である。

    Competitive research funding

  • Behaivior of some metal complexans in pollutedwater and its control.

    MURAMOTO Shigeki, OKAMURA Hideo, NAKASHIMA Susumu, AOYAMA Isao

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for General Scientific Research (C), Grant-in-Aid for General Scientific Research (C), OKAYAMA UNIVERSITY, 1993 - 1995

    The surfactans are complexing agents with high compatibility used in many kinds of industries. The range of used of man-made complexing agents is very wide and includes emulsigying, domestic washing, machine washing, and fertilizer. The comsummption volumes of detergents keeep on increasing year by year. They affected water quality, agricultural products, fish, shellfish, and water plants etc. This research was mainly composed next of three subject. (1) Change in concentration and distribution of metal complexan in city river waters affecting domestic area through a day was confirmed by the effect of wasshing time in the 24 hours human activity. Also, the concentration of anionic surface active agents was coresponding with or without working time of factory. (2) Effect of metal complexan, anionic surface-active agents on the metal accumulation of plant in water-plant system. The amount of accumulation of surface-active agents was depend on the exposure concentration and exposure time in weater. Also, the order of cencentration of sodium lauryl sulfate, SDS was root>stem of plant exposered with SDS containing water. The root tissue was more sensitivity to SDS comparedwith that of stem of plant. (3) Effect of micro-energy with magnetic power on the decreasing of micro-energy with magnetic power on the decreasing of growth of geen algae which produce the some kind of musty odor of drinking water, organic substances polution in domestic area in Japan. (4) The effecs of iron forms on the growth of four cyanobacteria were studied. Almost cyanobacteria was supposseds in the EDTA free CT medium because of no ability to utilize colloidal iron and iron oxides for its growth. These results suggested that some kinds of complexans affected to aquatic plants and aquatic animals for the growth and its accumulation.

    Competitive research funding

  • バイオサイドが海洋環境に及ぼす影響評価

    Competitive research funding

  • バイオアッセイを活用した廃棄物の管理

    Competitive research funding

  • Waste management using bioassay

    Competitive research funding

  • Environmental assessment of biocide on marine environments.

    Competitive research funding