Genotoxic effects of binary mixtures of xenoandrogens (tributyltin, triphenyltin) and a xenoestrogen (ethinylestradiol) in a partial life-cycle test with Zebrafish (Danio rerio)

• Published in: Environment international Vol. 33; no. 8; pp. 1035 - 1039
• Main Authors: Micael, J., Reis-Henriques, M.A., Carvalho, A.P., Santos, M.M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.11.2007; Elsevier
• Subjects: Agnatha. Pisces; Androgens - toxicity; Animal, plant and microbial ecology; Animals; Applied ecology; Biological and medical sciences; Chemical mixtures; Danio rerio; DNA Damage; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Endocrine disrupting chemical; Erythrocytes, Abnormal; Estrogens - toxicity; Ethinyl Estradiol - toxicity; Ethinylestradiol; Fundamental and applied biological sciences. Psychology; Genotoxicity; Life Cycle Stages; Marine and brackish environment; Mutagens - toxicity; Organotin Compounds - toxicity; Trialkyltin Compounds - toxicity; Tributyltin; Triphenyltin; Water Pollutants, Chemical - toxicity; Zebrafish; Zebrafish - physiology; Ethinylestradiol; Genotoxicity; Chemical mixtures; Triphenyltin; Zebrafish; Tributyltin; Endocrine disrupting chemical; Ecotoxicology; Toxicity; Antifouling paint; Endocrine disruptor; Life cycle; Binary mixture; Vertebrata; Pisces; Environment impact; Water pollution; Cyprinidae; Tin Organic compounds; Biocide; Organic stannane; Organic compounds; Environmental protection
• ISSN: 0160-4120; 1873-6750
• DOI: 10.1016/j.envint.2007.06.004

A partial life-cycle test with the model fish Danio rerio was performed in order to evaluate the genotoxic potential of binary mixtures of xenoandrogenic (tributyltin — TBT; triphenyltin — TPT) and an estrogenic compound (ethinylestradiol — EE2). Five days post-fertilisation larvae were diet-exposed to environmental relevant concentrations of TBT and TPT (25 ng/g–100 ng/g), and water-exposed to ethinylestradiol (3.5 ng/L) for a four-month period; binary mixtures of TBT plus EE2 and TPT plus EE2 were run in parallel. The erythrocytic nuclear abnormalities (ENA) assay in circulating erythrocytes was used to evaluate genotoxicity in the end of the four-month exposure period. A significant increase (p<0.05, Kruskall–Wallis non-parametric ANOVA) in ENA frequency, in comparison with control animals, was observed in those animals exposed to TBT and TPT (the highest doses only), and to EE2 and the binary mixtures, although neither synergistic nor additive effects of the tested compounds were evident. Overall, the results clearly indicate that chronic exposure to low levels of TBT, TPT, EE2 and binary mixtures of TBT plus EE2 and TPT plus EE2 are genotoxic to zebrafish, which may suggest that wild fish populations may be under increased DNA damage in areas contaminated by these endocrine disrupting chemicals.