M4 AM Endocrine Disruption in Fish
Monday, 14 November 2005: 8:00 AM - 11:40 AM in Ballroom 4

(JOH-1117-837300) Xenoestrogen exposure and altered reproductive timing in Puget Sound English sole.

Johnson, L¹, Lomax, D¹, Myers, M¹, Swanson, P¹, Felli, L¹, West, J², O'Neill, S², ¹ NOAA Fisheries - Northwest Fisheries Science Center, Seattle, WA, United States² Washington State Department of Fish and Wildlife, Olympia, WA, United States

ABSTRACT- Vitellogenin, a yolk protein produced in the liver of oviparous animals in response to estrogens, normally occurs only in sexually mature females with developing eggs. However, males can synthesize vitellogenin when exposed to environmental estrogens, making the abnormal production of vitellogenin in male animals a useful biomarker for xenoestrogen exposure. We surveyed English sole from a number of sites in Puget Sound, Washington for evidence of xenoestrogen exposure, using vitellogenin production in males as an indicator. Significant levels of vitellogenin were found in male fish from several urban sites, with especially high numbers of fish affected in Elliott Bay in Seattle. At the Elliott Bay sites where abnormal vitellogenin production was observed in male sole, female English sole were entering vitellogenesis earlier in the season than sole from other sites, and final egg maturation and spawning appeared to be delayed. Additionally, female sole were maturing at a smaller size and younger age at Elliott Bay sites that at other reference sites in Puget Sound. In male sole, spawning was delayed at the Elliott Bay sites, but other aspects of reproductive development were unchanged. We are currently investigating the impact of environmental estrogens on the reproductive physiology of English sole by measuring steroid hormone levels and expression of StAR protein, which is involved in steroid biosynthesis.

Key words: marine fish, xenoestrogens, reproductive toxicology, endocrine disruption