Trace Element Concentrations in Blood and Scute Tissues from Wild and Captive Hawaiian Green Sea Turtles (Chelonia mydas)

• Published in: Environmental toxicology and chemistry Vol. 40; no. 1; pp. 208 - 218
• Main Authors: Shaw, Katherine R., Lynch, Jennifer M., Balazs, George H., Jones, T. Todd, Pawloski, Jeff, Rice, Marc R., French, Amanda D., Liu, Jing, Cobb, George P., Klein, David M.
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01-01-2021
• Subjects: Aquarium; Aquatic reptiles; Blood; Captive; Captivity; Chelonia mydas; Chromium; Copper; Diet; Exposure; Food; Hawaii; Heavy metals; Immune response; Inductively coupled plasma mass spectrometry; Marine turtle; Mass spectrometry; Mass spectroscopy; Occupational exposure; Public domain; Rehabilitation; Reptile; Reptiles & amphibians; Sea turtles; Selenium; Trace elements; Wildlife; Hawaii; United States > US; Hawaii; Reptile; Aquarium; Captive; Heavy metals; Marine turtle
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1002/etc.4911

Sea turtles are exposed to trace elements through water, sediment, and food. Exposure to these elements has been shown to decrease immune function, impair growth, and decrease reproductive output in wildlife. The present study compares trace element concentrations in green turtles in captivity at Sea Life Park Hawaii (n = 6) to wild green turtles in Kapoho Bay, Hawaii, USA (n = 5–7). Blood and scute samples were collected and analyzed for 11 elements via inductively coupled plasma‐mass spectrometry (ICP‐MS). Selenium was significantly greater (p < 0.05) in the blood of captive turtles compared with wild turtles, whereas V, Ni, and Pb were significantly greater in the blood of wild turtles. In scute, V, Cu, Se, and Cr were significantly greater in captive turtles, whereas As was significantly greater in wild turtles. Pelleted food fed to the captive turtles and representative samples of the wild turtle diet were analyzed via ICP‐MS to calculate trophic transfer factors and daily intake values. Wild turtles had greater estimated daily intake than captive turtles for all elements except Cu and Se. Because captive turtles are fed a diet very different from that of their wild counterparts, captive turtles do not represent control or reference samples for chemical exposure studies in wild turtles. No toxic thresholds are known for sea turtles, but rehabilitation and managed care facilities should monitor sea turtle elemental concentrations to ensure the animals' health. Environ Toxicol Chem 2021;40:208–218. © 2020 SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA.
The differences in elemental concentrations between captive and wild turtles are primarily due to their food source. Captive turtles are given a pelleted food that is a mixture of animal and plant protein products with additives, whereas wild turtles have a primarily herbivorous diet. Asterisk indicates significant difference (p < 0.05) between captive and wild turtles.