Chemical Contaminants Found in the Gastrointestinal Tract of Loggerhead Sea Turtles (Caretta caretta)

Plastic is becoming increasingly more abundant in the marine environment. Plastic ingestion has been shown to be a source of exposure to a variety of harmful compounds, such as polycyclic aromatic hydrocarbons (PAHs), bisphenol A (BPA), and phthalates, which are known for their negative physiological effects on the endocrine system as well as their ability to adsorb and leach from plastic into the bodies of marine organisms. The physiological effects of these compounds on loggerhead sea turtles (Caretta caretta) still remain unknown. This study investigated the presence of toxicants on marine plastic samples collected from Bermuda, the Sargasso Sea, and the North Atlantic Ocean. Gas chromatography/triple quadruple mass spectrometry (GC/MS) analysis showed PAHs were present on many plastic debris samples. Plastic additives such as phthalates and (BPA) were also found. ΣPAH concentrations for anthracene, chrysene, benzo[b]fluoranthene, and benzo[k]fluoranthene for 2013 environmental plastic samples averaged 26.7ng/g of plastic. This study also examined the presence of these compounds in fluids from the stomach, small intestine, and large intestine from two adult loggerhead turtles. GC/MS analysis also showed the presence of BPA and phthalates on plastic samples, as well as in two out of the six gastrointestinal fluids samples. Average ΣPAH concentration for GI fluids for the loggerheads in the study was 58.7 ng/mL. This study showed plastic could be a significant source of PAHs in sea turtles and the first to detect PAHs in sea turtle GI fluid. Loggerhead sea turtles are a long living species and could accumulate high concentrations of these endocrine-disrupting chemicals throughout their lifetime.