Potential effects of brevetoxins and toxic elements on various health variables in Kemp's ridley (Lepidochelys kempii) and green (Chelonia mydas) sea turtles after a red tide bloom event

• Published in: The Science of the total environment Vol. 605-606; pp. 967 - 979
• Main Authors: Perrault, Justin R., Stacy, Nicole I., Lehner, Andreas F., Mott, Cody R., Hirsch, Sarah, Gorham, Jonathan C., Buchweitz, John P., Bresette, Michael J., Walsh, Catherine J.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.12.2017
• Subjects: Disease; Fibropapillomatosis; Health; Heavy metal; Immune system; Marine turtle; Disease; FP; A:G; SRM; BSA; QC; PbTx; DBS; RNS; Immune system; LOD; PBS; SCLmin; Health; DCF; RBCs; BCI; SOD; UMAW; HEL; PBS-T; rpm; PCA; Heavy metal; CV; PC; AU; ROS; Marine turtle; NIST; PIT; Fibropapillomatosis; ICP-MS; CV-AAS; ELISA
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2017.06.149

•Kemp’s ridley and green sea turtles were analyzed for brevetoxins, toxic elements, and health in Florida’s Big Bend•Brevetoxins were correlated with indices of inflammation and immunostimulation in marine turtles•Brevetoxin may serve as a potential fibropapillomatosis tumor promoter in green turtles•Toxic elements were related to oxidative stress, decreased body condition, and increased tumor growth•Fibropapillomatosis likely results in inflammatory and immunomodulatory responses in green turtles [Display omitted] Natural biotoxins and anthropogenic toxicants pose a significant risk to sea turtle health. Documented effects of contaminants include potential disease progression and adverse impacts on development, immune function, and survival in these imperiled species. The shallow seagrass habitats of Florida's northwest coast (Big Bend) serve as an important developmental habitat for Kemp's ridley (Lepidochelys kempii) and green (Chelonia mydas) sea turtles; however, few studies have been conducted in this area. Our objectives were (1) to evaluate plasma analytes (mass, minimum straight carapace length, body condition index [BCI], fibropapilloma tumor score, lysozyme, superoxide dismutase, reactive oxygen/nitrogen species, plasma protein electrophoresis, cholesterol, and total solids) in Kemp's ridleys and green turtles and their correlation to brevetoxins that were released from a red tide bloom event from July–October 2014 in the Gulf of Mexico near Florida's Big Bend, and (2) to analyze red blood cells in Kemp's ridleys and green turtles for toxic elements (arsenic, cadmium, lead, mercury, selenium, thallium) with correlation to the measured plasma analytes. Positive correlations were observed between brevetoxins and α2-globulins in Kemp's ridleys and α2- and γ-globulins in green turtles, indicating potential immunostimulation. Arsenic, cadmium, and lead positively correlated with superoxide dismutase in Kemp's ridleys, suggesting oxidative stress. Lead and mercury in green turtles negatively correlated with BCI, while mercury positively correlated with total tumor score of green turtles afflicted with fibropapillomatosis, suggesting a possible association with mercury and increased tumor growth. The total tumor score of green turtles positively correlated with total protein, total globulins, α2-globulins, and γ-globulins, further suggesting inflammation and immunomodulation as a result of fibropapillomatosis. Lastly, brevetoxin concentrations were positively related to tumor score, indicating potential tumor promotion by brevetoxin. These results signify that brevetoxins and toxic elements elicit various negative effects on sea turtle health, including immune function, oxidative stress, and possibly disease progression.