Abstract
Sea turtles tend to accumulate high metal levels in their tissues and are considered excellent pollution bioindicators. Studies concerning metal contamination in hatchlings, however, are non-existent for one of the most abundant species in Brazil, green sea turtles, while several other metal assessments in juvenile muscles are still scarce. In this context, this study aimed to analyze the concentrations of 12 elements in kidney and muscle samples from green sea turtles (Chelonia mydas; n = 24) found stranded in Rio de Janeiro, southeastern Brazil. Elemental concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS). The presence of fibropapillomatosis, an increasingly common disease in sea turtles which has been associated to metal contamination, was also evaluated. Most elements (Mn, Fe, Co, Ni, Cu, Zn, Cd, Hg, and Pb) were significantly higher in liver, while Al and As were significantly higher in muscle tissue, indicating bioaccumulation of the latter two elements. No differences between juvenile male and female green turtles were observed for either liver or kidney concerning the investigated elements. Literature comparisons of studies conducted in other areas throughout the Brazilian coast indicate higher concentrations of Cd, Mn, As, Hg, and Zn in kidneys, of probable anthropogenic origin. Several statistically significant inter-elemental correlations were observed between toxic elements, indicating similar sources for these environmental contaminants. Significant correlations between Hg in muscle and kidney and As in the same organs suggest bioaccumulation of both elements in muscle. Three individuals assessed herein exhibited fibropapillomatosis, and further assessments in this regard and potential correlations to the detected metal concentrations are currently being carried out. In addition, evaluations concerning other toxic compounds, as well as deleterious cellular effects, are also underway, since total metal concentrations do not reflect total elemental bioavailability.
Highlights
Green sea turtle hatchlings exhibit a pelagic phase lasting for about 5–10 years, during which they remain associated with pelagic currents (Musick and Limpus, 1997), while juveniles generally recruit to developmental habitats prior to moving to adult feeding grounds (Arthur et al, 2008)
This study aimed to analyze the concentrations of 12 metals and metalloids in kidney and muscle samples of male and female hatchling and juvenile green sea turtle individuals found stranded in the state of Rio de Janeiro, southeastern Brazil and perform preliminary associations between the presence of these contaminants and the development of fibropapillomatosis
The data reported includes baseline levels for both green turtle hatchlings and for Al, As, Co, Fe, Hg, Mn, and Ni in muscle tissue for juvenile and hatchling green sea turtles, as no studies concerning metal levels in hatchling kidney and muscle samples are available for Brazil and Al, As, Co, Fe, Hg, Mn, and Ni have not yet been determined in muscle for any age in green turtle specimens in Brazil
Summary
Among environmental pollutants generated by anthropogenic activities, metals are of significant concern due to their environmental persistence and potential toxicity (Marins et al, 1998; Marcovecchio, 2000; Baird, 2002; Miller et al, 2002; Melo, 2003).Long lived animals, such as sea turtles, tend to accumulate higher levels of metals in their tissues compared to the water column (De la Lanza-Espino et al, 2000; Aguilar et al, 2002), and are, considered competent chemical contamination indicators (Caurant et al, 1999). In addition to deleterious biochemical effects, sea turtles have been reported to develop fibropapillomatosis due to contaminant exposure, including metals (Keller et al, 2014; Da Silva et al, 2016), and higher frequencies of fibropapillomatosis have been reported in contaminated environments (Formia et al, 2007; Guimarães et al, 2013), indicating a potential link between chemical environmental contamination, oxidative stress, dysregulation of metabolic functions and the consequent development of this disease This condition is caused by a herpesvirus and, in turtles, is characterized by the appearance of tumor masses on different parts of the body, such as the oral cavity, eyes, skin, carapace and, in about 25–30% of affected individuals, internal organs (Herbst, 1994; Aguirre et al, 2002; Aguirre and Lutz, 2004). This study aimed to analyze the concentrations of 12 metals and metalloids in kidney and muscle samples of male and female hatchling and juvenile green sea turtle individuals found stranded in the state of Rio de Janeiro, southeastern Brazil and perform preliminary associations between the presence of these contaminants and the development of fibropapillomatosis
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
