Chemical Element Concentrations in the Blood of Green Turtles (Chelonia Mydas) Captured at Fernando De Noronha Marine National Park, Brazil

Abstract

Green turtles may be used as biomonitors of marine environments because of their longevity and feeding habits (omnivorous during the first years of life and herbivorous during the juvenile and adult stages), which can indicate the degree of ocean contamination in the areas where they feed. Studies of metal and chemical element concentrations in the blood of green turtles are still rare; therefore, the results are difficult to interpret, although it appears that the serum levels of certain elements found in green turtles are much higher than the minimal risk levels indicated for human health. The objective of this study was to measure the concentrations of the essential elements Calcium (Ca), Selenium (Se), Zinc (Zn), Manganese (Mn), Cobalt (Co), Copper (Cu) and Molybdenum (Mo) and the metals Aluminum (Al), Arsenic (As), Lead (Pb), Cadmium (Cd), Lithium (Li), Cesium (Cs), Barium (Ba), Rubidium (Rb), Uranium (U), Thallium (Tl), Beryllium (Be), Antimony (Sb) and Tellurium (Te) in the blood of 31 juvenile green turtles captured in Fernando de Noronha Marine National Park (Parque Nacional Marinho de Fernando de Noronha), Brazil, and to correlate these concentrations with the curved carapace length to identify possible cumulative effects. Furthermore, because the basal levels for these elements have not yet been established for green turtles, the effects of these chemicals on the health of the species are still unknown. Thus, most of these contaminants should be described as alarming until further clarification.