Trace and macro elements concentrations in the blood and muscle of loggerhead turtles (Caretta caretta) from the Canary Islands, Spain

Sea turtles can bioaccumulate heavy metals and trace elements over the years, therefore they can be used as bioindicators of pollution in the marine environment. The aim of this study was to analyze seventeen elements in blood and muscle of Caretta caretta from the Canary Islands and compare these concentrations in the two tissues. Thirteen blood samples and six muscle samples were collected from loggerhead turtles admitted to the Rescue Center of La Tahonilla. The samples were processed through microwave digestion and incineration. For the study of the data, a descriptive statistical analysis and a PERMANOVA were performed. All individuals in this study were juveniles (size <70 cm). The results of this study differ from previous studies on loggerhead sea turtles. All the elements analyzed were detected, with Na having the highest concentration in blood (75,379 +/- 30,066 mg/ kg) and muscle (222,626 +/- 156,049 mg/kg). Statistically significant differences were found between the concentration of Al, B, Ba, Ca, Fe, K, Na, Sr, V and Zn in each tissue analyzed. Compared to other studies, a higher Cu concentration was found both in blood (252.9 +/- 114.4 mg/kg) and in muscle (416 +/- 247.8 mg/kg). This study has provided new data on pollutants in loggerhead sea turtles and increased the information available for different geographic areas, although more studies are needed to understand the effects and impact of these pollutants on sea turtles.

Automated summary

The aim of this study was to analyze the concentration of heavy metals and trace elements in the blood and muscle of loggerhead sea turtles from the Canary Islands and compare them between the two tissues. The study found that all the elements analyzed were detected, with sodium having the highest concentration. Significant differences were found in the concentrations of aluminum, boron, barium, calcium, iron, potassium, sodium, strontium, vanadium, and zinc between the two tissues. The study also found higher copper concentrations compared to previous studies.