Chlorinated Persistent Organic Pollutants (PCDD/Fs and PCBs) in Loggerhead Sea Turtles Stranded along the Central Adriatic Coast

Simple Summary Persistent organic pollutants (POPs) are a group of organic compounds characterized by long-range transport, persistence, bioaccumulation, and high toxicity. They can be found in aquatic environments where they can be ingested by marine organisms. As a long-lived, widely distributed, and opportunistic predator, the loggerhead turtle (Caretta caretta) is a sentinel species in the Mediterranean Sea, and it can also be considered a bioindicator of the health of the sea in terms of contaminants. In this study, 44 C. caretta stranded along the Adriatic coast were selected, considering sex and curved carapace length (CCL) as a proxy of age. The fat tissues and the livers of the animals were sampled and analyzed for studying the contamination level of chlorinated POPs in relation to sex and size. This work points the focus on the importance of monitoring these contaminants in C. caretta to evaluate the anthropic effects on the marine environment. Persistent organic pollutants are widespread in the marine environment. They can bioaccumulate and biomagnify in marine organisms through the food web with a potentially toxic effect on living organisms. The sea turtle Caretta caretta is a carnivorous animal with opportunistic feeding behavior. These turtles tend to bioaccumulate pollutants through food, and hence they can be considered an indicator of chemical pollutants in the marine ecosystem. In this study, 44 loggerhead sea turtles were considered, and liver and fat tissue were sampled from each of them to investigate the levels of dioxins (PCDD/Fs) and polychlorinated biphenyls (PCBs) in sea turtles and their potential correlation with sex and size in terms of curved carapace length (CCL). Results suggested that these contaminants were easily bioaccumulated, and PCBs were predominant compared to dioxins in both liver and fat tissue. The congener patterns were similar to those found in sea fish. Moreover, there were no differences in the contamination levels between females and males, nor was there a correlation with the size. There is a need to harmonize the methodological approaches to better evaluate the results and trends over time and to monitor the species and indirectly the health status of the marine environment.

Automated summary

This study investigated the levels of chlorinated POPs in loggerhead sea turtles in the Mediterranean Sea and found that these pollutants can easily bioaccumulate in the turtles. The results also showed that there was no correlation between the contamination levels and the sex and size of the turtles. Harmonizing methodological approaches is necessary to better evaluate the results and trends over time and to monitor the health status of the marine environment.