title: Effects of bis(2-ethylhexyl) phthalate and benzo[a]pyrene on the embryos of Japanese medaka (Oryzias latipes).
abstract: Effects of two widely found chemical pollutants, bis(2-ethylhexyl) phthalate (DEHP) and benzo[a]pyrene (BaP), on the embryos of Japanese medaka were investigated. The embryos were exposed to different concentrations (0.01, 0.1, 1, and 10μg/l) of DEHP and BaP. The following were investigated: (1) hatching time and hatching rate in embryos, (2) mortality, sex ratio, body weight and gonadosomatic index (GSI) in adulthood. These two chemicals delayed the hatching time without dose-dependence, but these chemicals had no effect on hatching rate. Mortality was raised and body weight was reduced by DEHP and BaP-treatment; distortion of sex ratio appeared at the lowest concentration of DEHP tested. GSI was decreased because of the BaP-treatment. DEHP and BaP negatively affected Japanease medaka embryos, and the influences of the effects continued into adult stage. Moreover, the effects did not appear to be necessarily dose-dependent.
authors.affiliation: School of Materials Science, Japan Advanced Institute of Science and Technology, Ishikawa 923-1292, Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Chikae
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Hatano
authors.forename: Ryuzoh
authors.initials: R
authors.lastname: Ikeda
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Morita
authors.forename: Quamrul
authors.initials: Q
authors.lastname: Hasan
authors.forename: Eiichi
authors.initials: E
authors.lastname: Tamiya