부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.aquatox.2006.08.011 Byline: E. Bandelj (a), M.R. van den Heuvel (b), F.D.L. Leusch (c), N. Shannon (d), S. Taylor (d), L.H. McCarthy (a) Keywords: Endocrine disrupter; Androgen; Bioassay; Mosquitofish Abstract: This study combined bioassay-derived and direct chemical analysis of steroidal compounds in pulp and paper and municipal sewage effluent in order to determine the cause of masculinization of female mosquitofish. The bioassays used in this study consisted of androgen and estrogen receptor binding, and aromatase inhibition using tissues from rainbow trout. This study observed no masculinization of female mosquitofish from a pulp and paper mill effluent that was previously observed to cause this effect. Mosquitofish sampled from the receiving environment of the same mill verified that masculinization was not occurring in the wild. The municipal sewage effluent also had no masculinizing effect. In vitro bioassays indicated significant sources of both androgens and estrogens in the effluents tested with sewage effluent having both the highest estradiol (41ng/L) and testosterone (182ng/L) equivalent concentration. These results could not be attributed to any particular compounds measured in the effluents. Two compounds implicated in the masculinization of mosquitofish by pulp and paper effluent, androstenedione and androstadienedione required relatively large (10-100[mu]g/L) waterborne concentrations to elicit a masculinizing effect and neither of these compounds are likely to occur at levels this high in the natural environment. The potent aromatase inhibitor, 4-hydroxyandrostenedione also did not cause masculinization at 100[mu]g/L indicating that masculinization did not occur through this mechanism. The mammalian anti-androgen, cyproterone acetate was only partially effective in mosquitofish and reduced the severity of masculinization in the presence of methyl testosterone. While neither effluent masculinized mosquitofish, there was a significant reduction of in vitro ovarian steroid production with the most severe effects observed with the sewage effluent. Overall, this study found the disappearance of a masculinizing effect that had been previously observed; concluded that based on 21 days aqueous exposures androstenedione and androstadienedione are not likely candidates for mosquitofish masculinization, and showed that masculinization and in vitro steroid production are unrelated biological endpoints. Author Affiliation: (a) Ryerson University, Toronto, Ontario, Canada (b) Canadian Rivers Institute, University of Prince Edward Island, Department of Biology, Charlottetown, Canada (c) CRC for Water Quality and Treatment, Griffith University, Brisbane, Australia (d) Scion, Rotorua, New Zealand Article History: Received 24 July 2006; Revised 29 August 2006; Accepted 31 August 2006