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Dive into the research topics where Hitoshi Fukazawa is active.

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Featured researches published by Hitoshi Fukazawa.


Chemosphere | 2001

Identification and quantification of chlorinated bisphenol A in wastewater from wastepaper recycling plants.

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

Chlorination of harman and norharman with sodium hypochlorite and co-mutagenicity of the chlorinated products

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

Identification of co-mutagenic chlorinated harmans in final effluent from a sewage treatment plant

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

Development and validation of chemical and biological analyses to determine the antiestrogenic potency of resin acids in paper mill effluents.

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

Competitive interactions of chlorinated phenol compounds with 3,3′,5-triiodothyronine binding to transthyretin: detection of possible thyroid-disrupting chemicals in environmental waste water

Kiyoshi Yamauchi; Akinori Ishihara; Hitoshi Fukazawa; Yoshiyasu Terao


Journal of Health Science | 2002

Formation of Chlorinated Derivatives of Bisphenol A in Waste Paper Recycling Plants and Their Estrogenic Activities

Hitoshi Fukazawa; Masayuki Watanabe; Fujio Shiraishi; Tatsushi Shiozawa; Hidetsuru Matsushita; Yoshiyasu Terao


Environmental Toxicology and Chemistry | 2007

Occurrence and estrogenicity of phenolics in paper-recycling process water: Pollutants originating from thermal paper in waste paper†

Masanori Terasaki; Fujio Shiraishi; Hitoshi Fukazawa; Masakazu Makino


Toxicological Sciences | 2006

In Vitro and In Vivo Analysis of the Thyroid System-Disrupting Activities of Brominated Phenolic and Phenol Compounds in Xenopus laevis

Yumiko Kudo; Kiyoshi Yamauchi; Hitoshi Fukazawa; Yoshiyasu Terao


Environmental Pollution | 2008

Organic pollutants in paper-recycling process water discharge areas: first detection and emission in aquatic environment.

Masanori Terasaki; Hitoshi Fukazawa; Yukinori Tani; Masakazu Makino


Journal of Environmental Chemistry | 2004

Analysis and Estrogenic Activity of Bisphenol A and Other Chemicals Released from Waste Paper by Pulping

Masayuki Watanabe; Hitoshi Fukazawa; Fujio Shiraishi; Tatsushi Shiozawa; Yoshiyasu Terao

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Fujio Shiraishi

National Institute for Environmental Studies

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