Concentration- and Time-dependent Effects of the Synthetic Estrogen, 17alpha-ethinylestradiol, on Reproductive Capabilities of the Zebrafish, Danio rerio

摘要

There is increasing evidence that a number of environmental substances have the potential to disrupt the hormone systems of exposed organisms. Many of these so-called endocrine-disrupting compounds (EDCs) interfere with the sex steroid system and the hypothalamic-pituitary-gonad axis (Ankley & Johnson, 2004; Segner et al., 2006). As a consequence, EDCs disturb developmental and reproductive processes, and induce disruptions of either transitory and reversible (activational) or permanent and irreversible (organizational) nature (Giulette et al., 1995; Bigsby et al., 1999, Markey et al., 2003). The potential risk posed by EDCs for human and wildlife has instigated efforts to establish regulatory programs for EDC hazard assessment. Since the aquatic environment is a major sink for EDCs (Matthiessen & Sumpter, 1998), particular attention was given to the development and validation of testing approaches using fish (Andersen et al., 2000; Harries et al., 2000; Ankley et al., 2001; Seki et al., 2003). Mainly three small fish species are under consideration as test species, that is, fathead minnow (Pimephales promelas), medaka (Oryzias latipes), and zebrafish {Danio rerio).