Meeting Abstract
5.1 Tuesday, Jan. 4 Thyroid Endocrine Alterations in Wild Fish –San Francisco Bay Region Studies KELLEY, Kevin M*; HAMILTON, Andrew W; WAGGONER, Claire M; REYES, Jesus A; California State University, Long Beach (CSULB); Institute for Integrative Research on Materials, Environment and Society (www.IIRMES.org); CSULB (www.csulb.edu/depts/endo); Pacific Coast Environmental Conservancy (www.PCEConservancy.org) kmkelley@csulb.edu
Disruptions in the vertebrate thyroid endocrine system pose a serious threat to health and survival, since thyroid hormones play essential roles in growth and development, among other critical physiological functions. In the San Francisco Bay region, significant location-related differences in plasma concentrations of thyroxine (T4) and triidothyronine (T3) have been documented in two wild fish species, the shiner surfperch (Cymatogaster aggregata) and Pacific staghorn sculpin (Leptocottus armatus). Reduced T4 was observed in both species when sampled from contaminated locations such as Oakland Harbor or nearby San Leandro Bay, as compared with less impacted locations such as Bodega Bay, Redwood City, or Catalina Island. Reduced T4 levels were particularly correlated with increasing tissue concentrations of polychlorinated biphenyls (PCBs; mostly non-coplanar, lower-chlorinated congeners). In contrast, PCBs were positively correlated with T3 concentrations and the T3/T4 ratio, suggesting potential effects on the peripheral 5’-deiodinase system (converts T4 into more active T3). Additional studies indicate that the thyroid gland itself may also be impacted, since treatment of impacted fish with pituitary thyroid-stimulating hormone (TSH) failed to normally activate T4 production. Continuing studies are characterizing the potential roles of other organic contaminants and metals such as mercury and related phenotypic impacts (tissue proteome alterations). [Support by Regional Monitoring Program for Water Quality in SF Bay and NOAA-USC Sea Grant Program/California Coastal Conservancy]
