ROMANO, J.A.; RITTSCHOF, D.; HOLM, E.R.; MCCLELLAN-GREEN, P.; Duke University Marine Lab; Duke University Marine Lab; Naval Surface Warfare Center, Carderock Division; North Carolina State University: Possible Endocrine Disruption in Balanus amphitrite after Exposure to Fouling-Release Coatings

Fouling-release coatings based on silicone polymers rely on the formation of weak adhesive bonds between marine organisms and surfaces. In this study, we determined if steroid metabolism was altered among sibling barnacles Balanus amphitrite grown on two silicone polymer surfaces stored in the same container. The silicones used were Silastic T-2 (Dow Corning), a platinum catalyzed silicone polymer used in moldmaking and Veridian (Akzo Nobel), a silicone foul release polymer with a proprietary catalyst. Barnacles reared for eight weeks to approximately 1 cm basal diameter, were removed from surfaces and examined from morphological abnormalities. Some barnacles grown on the Veridian coating were of different morphology and were found to have adhesives that did not harden properly. Microsomes from both treatment reared barnacle groups and non-treated field animals were prepared and exposed to radiolabeled testosterone in order to visualize metabolites using a phosphoimager. Metabolites were extracted and separated by thin layer chromatography using a two solvent system. Silastic T-2 and non-treated field animal microsomes had similar patterns of steroid metabolism. Microsomes from barnacles grown on Veridian had altered steroid metabolism, specifically lacking the 16B-hydroxytestosterone metabolite. Since barnacles have a base plate and siblings were reared on the two test coating in the same container, the effect is possibly due to compounds diffusing from the coatings into the barnacles. A result of an inhibition in one or more enzymes, most probably a cytochrome P450, may be responsible for the altered metabolism of this steroid. Supported in part by grant N001403WX20502.