An unusual mortality event of manatees (Trichechus manatus latirostris) on Florida's east coast is challenging scientists to identify possible causes. One previously identified cause for manatee deaths is the toxic marine algae called 'Red Tide' (from west coast) and other factors could include infectious diseases, unknown algal toxins or water pollution through sewage and industrial process streams that may affect the health of vulnerable manatee populations. Identification of contaminants from tissue samples taken at necropsy or biologic samples from live animals may aid in the discovery of associations between toxic environmental exposures and morbidity/mortality of manatees in Floridian waters. To determine whether manatees are exposed to discharges of raw or treated wastewater, we aimed to identify and evaluate using mass spectrometry, the presence of anthropogenic chemicals in blood samples from apparently healthy manatees on two Florida coasts, Crystal River (CR) and Brevard County (BC). We screened manatee blood samples utilizing GC-MS/MS in scan mode. Manatee sera were pooled for each coast and the extracts were purified using solid phase extraction, evaporated and reconstituted before injection into the mass spectrometer. Each peak on the GC-MS chromatogram represents an individual compound that was identified using the National Institute of Standards and Technology (NIST) GC-MS library. The GC-MS scan analysis of pooled serum from CR coast identified 16 compounds with NIST probability above 35%. We found derivatives of serum metabolites, algal phytochemicals, and chemicals associated with the rubber, coal and plastic industry. One specific peak showed 70.7% probability match with cyclohexyldimethoxymethyl-silane compound. Similarly, BC pooled sample GC-MS analysis identified 3 compounds. Importantly, GC-MS scan analysis only results in tentative identification of compounds. Confirmatory analysis using authentic standards is ongoing to determine the presence and concentration of specific compounds in manatees, using targeted multiple reaction monitoring (MRM) with GC-MS/MS and LC-MS/MS.

Identification of environmental contaminants in blood samples of manatees from Florida's coasts

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.