Abstract

In 2008, the International Maritime Organization banned the use of organotins, such as tributyltin (TBT). Organotins are released from antifouling paints and can eventually lead to reproductive failure, lower fecundity, abnormal embryonic development, and decrease larval survival. Despite the ban, organotins can persist in the environment for decades, thus still posing a threat to susceptible species. In gastropods, organotin exposure can lead to the development of a condition known as imposex (a condition where females develop male reproductive appendage) and in severe cases, the vaginal opening is blocked, resulting in sterility. In the natural environment, imposex is almost exclusively associated with organotin exposure, to the point that imposex in gastropods is used as a biomarker for TBT contamination. In 2018, we found that over 40% of female Queen Conch adjacent to an industrial seaport, Port Everglades, Florida, had imposex. The Port Everglades conch had similar gonadal health and engage in reproductive activities at the same frequency as Florida Keys aggregations without imposex; however abnormal egg masses were found and previously identified in other studies. Adult Queen Conch will be collected, marked if laying an abnormal egg mass, and sexed/imposexed at the Port Everglades aggregation. I will report any correlation between imposex females and naked egg masses and describe the incidence of imposex within the aggregation. There may be other endocrine disruptors that might be causing imposex at Port Everglades, but the overwhelming evidence from the literature suggests organotin exposure. Future studies should include sediment and tissue assays to confirm organotin presence and concentration.

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