Reproduction and development of Japanese medaka following an early life stage exposure to xenoestrogens

• Published in: Aquatic toxicology 1998-12, Vol.44 (1), p.141-156
• Main Authors: Nimrod, A.C, Benson, W.H
• Format: Article
• Language: English
• Subjects: Agnatha. Pisces; Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Estradiol; estrogenic properties; fecundity; females; fry; Fundamental and applied biological sciences. Psychology; gonadosomatic index; growth; males; Medaka; Methoxychlor; mortality; Nonylphenol; Oryzias latipes; ova; p-nonylphenol; phenolic compounds; Reproductive toxicity; sex ratio; toxicity; viability; Xenoestrogens
• ISSN: 0166-445X; 1879-1514
• DOI: 10.1016/S0166-445X(98)00062-9

Japanese medaka were exposed to environmentally-relevant concentrations of environmental estrogens: nonylphenol (NP, 0.5, 0.8 and 1.9 μg l −1), methoxychlor (MXC, 0.2, 0.6 and 2.3 μg l −1) and estradiol (E2, 0.01, 0.12 and 1.66 μg l −1). Exposure occurred throughout the first month following hatch. E2 survival ratios following the exposure period were significantly altered compared to control groups. Following a month period of `growout' in dilution water only, sex ratios were measured and reproductive capabilities assessed. No alteration in sex ratios was observed following treatment with NP or MXC. All three concentrations of E2 were sufficient to produce exclusively female populations. There was no depreciation in reproductive capability in the NP or MXC-treated fish as measured by fecundity, viability of eggs, or hatchability of eggs. E2-treated female fish had a lower fecundity in the highest concentration.