ASSOCIATIONS BETWEEN LEVELS OF PERSISTENT ORGANIC POLLUTANTS AND TRANSCRIPTIONAL BIOMARKERS IN LOGGERHEAD SEA TURTLES FROM CENTRAL ADRIATIC SEA (ITALY)

Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) are considered priority contaminants which bioaccumulate through the food webs affecting the biology of a variety of resident and migratory species, including sea turtles. However, studies on the evaluation of toxicological biomarkers of exposure to PAHs and PCBs in sea turtles are very scarce. Within the present work we show a first field study where we quantify the association between plasma concentrations of PAHs/PCBs and whole blood cell expression of gene biomarkers in juvenile loggerhead sea turtles (Caretta caretta) recovered along the western coasts of central Adriatic sea. Detectable levels of PAHs were found in all plasma samples examined. On the contrary, only three PCB congeners (i.e. PCB52, PCB95, and PCB149) were detected showing percentages of detection in the range between 48% and 57%. A significant correlation between 3 of the 6 gene biomarkers assessed (i.e. HSP60, CYP1A and ERα) and plasma levels of some PAH congeners was found. In contrast, any significant association between PCB burden and gene expression was observed. The relation between PAH concentration and gene expression in whole blood cells suggests that these genes respond to environmental contaminant exposure and are promising candidate for the development of biomarkers for monitoring POP exposure in sea turtles.