Ten-week exposure to treated sewage discharge has relatively minor, variable effects on reproductive behavior and sperm production in goldfish

Authors

  • Heiko L. Schoenfuss,

    1. Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota, 1980 Folwell Avenue, St. Paul, Minnesota 55108, USA
    Search for more papers by this author
  • James T. Levitt,

    1. Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota, 1980 Folwell Avenue, St. Paul, Minnesota 55108, USA
    Search for more papers by this author
  • Glen Van Der Kraak,

    1. Department of Zoology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    Search for more papers by this author
  • Peter W. Sorensen

    Corresponding author
    1. Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota, 1980 Folwell Avenue, St. Paul, Minnesota 55108, USA
    • Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota, 1980 Folwell Avenue, St. Paul, Minnesota 55108, USA
    Search for more papers by this author

Abstract

It is well established that effluent from many sewage treatment plants (STPs) possesses estrogenic properties; however, the biological significance of this estrogenicity to fish reproductive behavior and sperm production is unknown. This study tested the hypothesis that 10-week exposure to a STP effluent with well-established estrogenic properties compromises the reproductive vigor of mature goldfish by decreasing the intensity of their reproductive drive and sperm production. Male goldfish were exposed for 10 weeks to one of four treatments: well water, a solvent control, 50 ng/L estradiol (E2), or undiluted effluent from a major metropolitan STP. Two trials were conducted, one in the winter and one in the summer when the effluent was chlorinated. Exposure to effluent in both the summer and winter trials induced small, but nonsignificant, decreases in the frequency of male spawning behaviors but had no effect on sperm production. Exposure to E2 caused a clear reduction in spawning behavior in one trial while causing reduced sperm production in both trials. We conclude that the effect of effluent exposure from this STP on adult fish is likely to be relatively minor and that the effluent's estrogenic properties may vary over the course of the year.

Ancillary