title: Recovery of a wild fish population from whole-lake additions of a synthetic estrogen.
abstract: Despite widespread recognition that municipal wastewaters contain natural and synthetic estrogens, which interfere with development and reproduction of fishes in freshwaters worldwide, there are limited data on the extent to which natural populations of fish can recover from exposure to these compounds. We conducted whole-lake additions of an active component of the birth control pill (17α-ethynylestradiol; EE2) that resulted in the collapse of the fathead minnow (Pimephales promelas) population. Here we quantify physiological, population, and genetic characteristics of this population over the 7 years after EE2 additions stopped to determine if complete recovery was possible. By 3 years post-treatment, whole-body vitellogenin concentrations in male fathead minnow had returned to baseline, and testicular abnormalities were absent. In the spring of the fourth year, adult size-frequency distribution and abundance had returned to pretreatment levels. Microsatellite analyses clearly showed that postrecovery fish were descendants of the original EE2-treated population. Results from this whole-lake experiment demonstrate that fish can recover from EE2 exposure at the biochemical through population levels, although the timelines to do so are long for multigenerational exposures. These results suggest that wastewater treatment facilities that reduce discharges of estrogens and their mimics can improve the health of resident fish populations in their receiving environments.
authors: Freshwater Institute, Fisheries and Oceans Canada , 501 University Crescent, Winnipeg, Manitoba R3T 2N6, Canada.
authors: Paul J
authors: PJ
authors: Blanchfield
authors: Karen A
authors: KA
authors: Kidd
authors: Margaret F
authors: MF
authors: Docker
authors: Vince P
authors: VP
authors: Palace
authors: Brad J
authors: BJ
authors: Park
authors: Lianne D
authors: LD
authors: Postma
mesh_terms: D000818:Animals; D004781:Environmental Exposure / Q000032:analysis*; D052918:Environmental Restoration and Remediation; D045166:Estradiol Congeners / Q000032:analysis / Q000633:toxicity*; D005260:Female; D005399:Fishes / Q000235:genetics / Q000502:physiology*; D060106:Lakes; D008297:Male; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D045166:Estradiol Congeners; D014874:Water Pollutants, Chemical