Carr James A, Gentles Angie, Smith Ernest E, Goleman Wanda L, Urquidi Lina J, Thuett Kerry, Kendall Ronald J, Giesy John P, Gross Tim S, Solomon Keith R, Van Der Kraak Glen
Department of Biological Sciences, Texas Tech University, Lubbock, Texas 79409, USA.
Environ Toxicol Chem. 2003 Feb;22(2):396-405.
Larval Xenopus laevis were exposed to one of four concentrations of atrazine (0, 1, 10, or 25 microg/L, 11 replicate tanks per treatment, 60-65 larvae per replicate) dissolved in an artificial pond water (frog embryo teratogenesis assay- Xenopus [FETAX]) medium beginning 48 h after hatching until the completion of metamorphosis. Separate groups of larvae (six replicate tanks per treatment, 60-65 larvae per replicate) were exposed to estradiol (100 microg/L), dihydrotestosterone (100 microg/L), or ethanol vehicle control dissolved in FETAX medium. None of the treatments affected posthatch mortality, larval growth, or metamorphosis. There were no treatment effects on sex ratios except for estradiol, which produced a greater percentage of female offspring. Exposure to either estradiol or 25 microg atrazine/L increased the incidence of intersex animals based on assessment of gonadal morphology. Atrazine did not reduce the size of the laryngeal dilator muscle, a sexually dimorphic muscle in this species. We conclude that environmentally relevant concentrations of atrazine do not influence metamorphosis or sex ratios and do not inhibit sexually dimorphic larynx growth in X. laevis. The incidence of atrazine-induced intersex animals was small (<5%) and occurred only at the greatest concentration of atrazine tested, a concentration that is rarely observed in surface waters in the United States.
孵化48小时后，将非洲爪蟾幼体暴露于溶解在人工池塘水（青蛙胚胎致畸试验 - 非洲爪蟾[FETAX]）培养基中的四种浓度的阿特拉津（0、1、10或25微克/升，每种处理11个重复水族箱，每个重复60 - 65只幼体）之一中，直至变态完成。将单独的幼体组（每种处理6个重复水族箱，每个重复60 - 65只幼体）暴露于溶解在FETAX培养基中的雌二醇（100微克/升）、二氢睾酮（100微克/升）或乙醇溶剂对照中。没有一种处理影响孵化后死亡率、幼体生长或变态。除了雌二醇使雌性后代的比例更高外，没有处理对性别比例产生影响。基于性腺形态评估，暴露于雌二醇或25微克阿特拉津/升都会增加雌雄同体动物的发生率。阿特拉津并未减小喉扩张肌的大小，喉扩张肌是该物种中的一种两性异形肌肉。我们得出结论，环境相关浓度的阿特拉津不会影响非洲爪蟾的变态或性别比例，也不会抑制其两性异形的喉部生长。阿特拉津诱导的雌雄同体动物的发生率很低（<5%），且仅在测试的最高阿特拉津浓度下出现，而该浓度在美国地表水中很少观察到。
