Hitoshi Fukazawa
University of Shizuoka
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Publication
Featured researches published by Hitoshi Fukazawa.
Chemosphere | 2001
Hitoshi Fukazawa; Kentaro Hoshino; Tatsushi Shiozawa; Hidetsuru Matsushita; Yoshiyasu Terao
Chlorinated derivatives of bisphenol A were detected in the final effluents of eight paper manufacturing plants in Shizuoka, Japan, where thermal paper and/or other printed paper is used as the raw material. Their amounts were determined by gas chromatography/mass spectrometry (GC/MS) after treatment with N, O-bis(trimethylsilyl)trifluoroacetamide, and ranged from traces to 2.0 microg/l. They are likely produced by chlorination of bisphenol A, which was released into the effluents from the pulping process of wastepaper, during or after bleaching with chlorine.
Mutation Research-genetic Toxicology and Environmental Mutagenesis | 2000
Koji Nakano; Kayoko Suyama; Hitoshi Fukazawa; Mitsuo Uchida; Keiji Wakabayashi; Tatsushi Shiozawa; Yoshiyasu Terao
Harman and norharman are widely distributed in the environment and consequently contaminate in domestic waste-water. It has been reported that they have co-mutagenic activity in the presence of non- mutagenic aromatic amines such as aniline and o-toluidine with S9 mix. When these beta-carbolines were treated with sodium hypochiorite under mild conditions, chlorinated derivatives were produced. Among them, 6-chloroharman and 6-chloronorharman showed much more potent co-mutagenic activities than harman and norharman in the presence of o-toluidine toward Salmonella typhimurium TA98 with S9 mix. These results suggest that the chlorination of harman and norharman occurs during disinfection at the sewage plant to produce potent co-mutagens that contaminate river water.
Mutation Research-genetic Toxicology and Environmental Mutagenesis | 2001
Hitoshi Fukazawa; Hidetsuru Matsushita; Yoshiyasu Terao
Harman (1-methyl-9H-pyrido[3,4-b]indole) reacted readily with sodium hypochlorite in an aqueous medium to give the mono-chlorinated derivatives, which reportedly have greater co-mutagenic activity than harman in the presence of o-toluidine toward Salmonella typhimurium TA 98 with S9 mix. Mono-chlorinated harmans were detected by concentration using blue rayon (BR) and GC/MS analysis in the final effluent from a sewage treatment plant in Shizuoka, Japan. The amounts adsorbed for 24h were 1-45ng/gBR for mono-chlorinated harman and 110-730ng/gBR for harman.
Environmental Science & Technology | 2009
Masanori Terasaki; Fujio Shiraishi; Hitoshi Fukazawa; Masakazu Makino
This study combined chemical analysis and bioassays of paper mill effluents and their components in order to determine their antiestrogenic activity. The bioassay comprised a yeast two-hybrid assay incorporating the estrogen receptor alpha (hERalpha) and an hERalpha competitive enzyme-linked immunosorbent assay (ELISA). Samples were fractionated by solid phase extraction (SPE) with a C18 disk and a Florisil cartridge to obtain four fractions. The final fraction, eluted with methanol from the Florisil cartridge after pre-extraction by the C18 disk, was the most active in the two-hybrid assay, and its antiestrogenic potency, expressed as the equivalent concentration to 4-hydroxytamoxifen (OHT), was 277 nM. Seven resin acids had antiestrogenic activity in the active fraction as determined by gas chromatography/mass spectrometry (GC/MS), and their concentration levels ranged from 0.11 to 12 microg/L. All the resin acids exhibited greater activity than OHT; their activity relative to OHT ranged from 2.8- to 4.0-fold in the yeast two-hybrid assay. Based on the chemical analysis data and relative potency of resin acids from the yeast two-hybrid assay, the contribution ratio of resin acids accounted for 72% of the observed antiestrogenic activity of the extract. Furthermore, no resin acid showed any affinity for the estrogen receptor in the ELISA. This study showed that analysis combining the SPE method and the yeast two-hybrid assay is likely to be effective for the comprehensive monitoring of resin acids in paper mill industrial discharge areas.
Toxicology and Applied Pharmacology | 2003
Kiyoshi Yamauchi; Akinori Ishihara; Hitoshi Fukazawa; Yoshiyasu Terao
Journal of Health Science | 2002
Hitoshi Fukazawa; Masayuki Watanabe; Fujio Shiraishi; Tatsushi Shiozawa; Hidetsuru Matsushita; Yoshiyasu Terao
Environmental Toxicology and Chemistry | 2007
Masanori Terasaki; Fujio Shiraishi; Hitoshi Fukazawa; Masakazu Makino
Toxicological Sciences | 2006
Yumiko Kudo; Kiyoshi Yamauchi; Hitoshi Fukazawa; Yoshiyasu Terao
Environmental Pollution | 2008
Masanori Terasaki; Hitoshi Fukazawa; Yukinori Tani; Masakazu Makino
Journal of Environmental Chemistry | 2004
Masayuki Watanabe; Hitoshi Fukazawa; Fujio Shiraishi; Tatsushi Shiozawa; Yoshiyasu Terao