title: Effects of bis(2-ethylhexyl) phthalate, γ-hexachlorocyclohexane, and 17β-estradiol on the fry stage of medaka (Oryzias latipes).
abstract: The effects of bis(2-ethylhexyl) phthalate (DEHP), γ-hexachlorocyclohexane (γ-HCH), and 17β-estradiol (E2) on the fry stage of medaka were investigated. The medaka fry were exposed to different concentrations (0.01, 0.1, 1, and 10μg/L) of these chemicals for 3 weeks after hatching. Then, mortality, body weight, sex ratio, and gonadosomatic index (GSI) of the matured fish (after 5 months) were measured. Mortality was increased significantly in the 10μg/L E2 group. Distortion of sex ratio was found in 1 and 10μg/L E2 groups. DEHP treated groups showed the GSI reduction only in male fish. All the γ-HCH and parts of the E2 treated groups showed the GSI reduction in both sexes. Exposure of DEHP, γ-HCH, and E2 during the fry stage affected normal maturation of medaka at the concentrations which had no impact on mortality or sex ratio.
authors.affiliation: School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1, Asahidai, Tatsunokuchi, Ishikawa 923-1292, Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Chikae
authors.forename: Ryuzoh
authors.initials: R
authors.lastname: Ikeda
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Hatano
authors.forename: Quamrul
authors.initials: Q
authors.lastname: Hasan
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Morita
authors.forename: Eiichi
authors.initials: E
authors.lastname: Tamiya