Concentrations of polycyclic aromatic hydrocarbons (PAHs) in liver samples of green turtles Chelonia mydas stranded in the Potiguar Basin, northeastern Brazil.

Sea turtles are affected by pollutants worldwide, and the polycyclic aromatic hydrocarbons (PAHs) have been detected in different types of samples and at high levels in some cases. The present study brings concentrations of 37 PAHs in liver samples of 17 green turtles Chelonia mydas stranded in northeastern Brazil [four with cutaneous tumors of fibropapillomatosis (FP), being classified as FP+]. Six PAHs were detected in 100% of the liver samples, and all alkylated PAHs were frequently quantified. High levels of phenanthrene (771.20 and 794.43 ng g-1 d.w.) and fluorene (1882.36 ng g-1 d.w.) were found in three females FP- (without FP cutaneous tumors). On the other hand, one green turtle FP+ had the higher level of naphthalene (531.70 ng g-1 d.w.), compound detected in 82.35 % of the samples. Our study brings additional baseline of organic pollutants in green turtles, improving knowledge on bioaccumulation of these compounds in sea turtles.

Bioaccumulation of total mercury, copper, cadmium, silver, and selenium in green turtles (Chelonia mydas) stranded along the Potiguar Basin, northeastern Brazil.

Sea turtles face several threats and pollution has become a major concern for their conservation worldwide. We analyzed samples of the liver, muscles, and kidneys of 38 Chelonia mydas stranded along the Potiguar Basin, northeastern Brazil, between 2015 and 2018 to determine the total Hg concentration (THg), as well as the concentrations of Cu, Cd, Ag, and Se. The relation between turtle size and element concentrations revealed a negative correlation for THg and Se (liver, muscles, and kidneys), Cu and Cd (liver and kidneys) and a positive correlation for Ag in the three organs analyzed. Concentrations of THg, Cu, Ag, and Se were high in the liver, highlighting the Cu concentration (median = 25.1150 µg g-1 w.w.), while the kidneys had the highest Cd levels (median = 12.2200 µg g-1 w.w.). There was significant difference between element concentrations and the three organs analyzed, except for Ag and Se concentrations in the muscle and kidney samples. Our study showed that green turtles found in Potiguar Basin, northeastern Brasil, have bioaccumulated inorganic elements which indicate the need of further investigations on the environmental quality of the region.