Synthetic hormones in wastewater effluents released into the aquatic environments may interfere with the normal endocrine systems of fish in receiving streams. Norgestrel (NGT) is a synthetic progestin widely used in oral contraceptives and frequently detected in wastewater effluents. In this study, adult female mosquitofish (Gambusia affinis) were exposed to three environmentally relevant concentrations of norgestrel (NGT) (i.e., 3.6, 35.8, and 368.0 ng L−1) for 42 d, fin morphology, histology of the ovary, and reproductive behaviors were evaluated. The results showed that NGT at all three concentrations caused an increased frequency of atretic follicular cells in ovaries and impaired mating behaviors exhibited by males toward the NGT-exposed females. In mosquitofish exposed to NGT at 35.8 and 368 ng L⁻¹, the anal fin of females had an increased length ratio of ray4/ray 6, an increased width of ray 3, and increased number of segments in ray 3. The histopathological analysis showed that exposure to NGT increased the incidence of spermatogenesis in ovaries. Mating behavior was impaired 58.4%, 65.7%, and 76.4% (P < 0.01 in all cases) when mosquitofish were exposed to NGT at 3.6, 35.6 and 368.0 ng L⁻¹, respectively. The rapid masculinization, the increased frequency of atretic follicles, the incidence of spermatogenesis in the ovary of female fish, and the altered reproductive behaviors suggest that wild populations of mosquitofish could be similarly affected inhabiting in NGT contaminated environments.

释放到水生环境中的废水中的合成激素可能会干扰接收流中鱼类的正常内分泌系统。Norgestrel（NGT）是一种合成的孕激素，广泛用于口服避孕药，并且经常在废水中检测到。在这项研究中，成年雌蚊（Gambusia affinis）暴露于三种环境相关浓度的炔诺孕酮（NGT）（即3.6、35.8和368.0 ng L-1）达42 d，鳍形态，卵巢的组织学和评估生殖行为。结果表明，在所有三个浓度下，NGT都会导致卵巢中闭孔卵泡细胞的频率增加，并且雄性对暴露于NGT的雌性表现出受损的交配行为。在35.8和368 ng L ^-1暴露于NGT的蚊鱼中因此，雌性的肛门鳍的射线4 /射线6的长度比增加，射线3的宽度增加，射线3的节段数量增加。组织病理学分析表明，接触NGT会增加卵巢中精子发生的发生率。 当蚊鱼分别在3.6、35.6和368.0 ng L ^-1的NGT下暴露时，交配行为受到损害的分别为58.4％，65.7％和76.4％（在所有情况下，P < 0.01）。快速的男性化，不规则卵泡的频率增加，雌鱼卵巢中生精的发生率以及生殖行为的改变表明，蚊子的野生种群也可能受到NGT污染环境的类似影响。