Sea turtle egg yolk and albumen as biomonitoring matrices for maternal burdens of organic pollutants

Brominated flame retardants in Caretta caretta sea turtles from the Adriatic Sea

This study evaluated the levels of 10 polybrominated diphenyl ethers (PBDEs) and 3 hexabromocyclododecanes (HBCDDs) in liver and fat tissue of 45 Caretta caretta stranded along the Adriatic Sea. The analytical methodology was based on gas or liquid chromatography coupled with high-resolution mass spectrometry. The mean values of PBDEs and α-HBCDD were 0.83 ± 0.39 and 0.069 ± 0.10 ng g-1 w.w. in liver, while 2.54 ± 0.80 and 0.56 ± 0.47 ng g-1 w.w. in fat tissue, respectively. The levels were higher in fat tissue than in liver. The PBDE profile was similar to that found in aquatic species while for HBCCDs, only the α-isomer was detected. No correlation between the contamination levels and sex and size was found. This study adds information about contamination levels of some brominated compounds in C. caretta, providing a background level in liver and fat tissue of loggerhead sea turtles from the Adriatic Sea.

Advancing Maternal Transfer of Organic Pollutants across Reptiles for Conservation and Risk Assessment Purposes

Embryonic exposure through maternally transferred pollutants can affect embryo vitality, survival, and health. Reptiles face global declines and are sensitive to embryonic pollutant exposure. Yet, they are often neglected in pollution risk assessment and conservation. We analyzed maternal transfer of organic pollutants in reptiles through a systematic extraction, homogenization, and integration of published data on organic pollutants measured in mother-egg pairs into a comprehensive database (DOI:10.5281/zenodo.10900226), complemented with molecular physical-chemical properties of the pollutants. Over four decades, 17 publications provided 19,955 data points shifting from legacy to emerging contaminants although research on newer contaminants lags regulatory and societal demands. Challenges including taxonomic bias, heterogeneity in sampled tissues, and 73% of censored data complicate comparative analyses. However, significant opportunities were identified including the use of the turtle Malachlemys terrapin and snake Enhydris chinensis as flagship species where a large amount of data is available across tissues (allowing investigation into physiological relations) and compounds (allowing insights into maternal transfer across the chemical universe). Data on other freshwater and marine turtles provide the possibility of exploring taxonomic patterns in this subgroup. The analysis, integrated database, and discussion present opportunities for research in an era where science needs to achieve more with limited wildlife data.

Persistent organic pollutants in the olive ridley turtle (Lepidochelys olivacea) during the nesting stage in the "La Escobilla" Sanctuary, Oaxaca, Mexico

Persistent organic pollutants (POPs) are chemical substances widely distributed in the environment by the runoff from anthropic activities and can be distributed and bioaccumulated or biomagnified in the environment, affecting the health of organisms. The sea turtle, Lepidochelys olivacea, is a long-lived organism, with migratory habits and feeding behaviors that allow exposure to various pollutants. This work aimed to determine long-term exposure to POPs in adult olive ridley turtles (L. olivacea), sampled during the nesting season, in "La Escobilla" Sanctuary. Blood samples were collected and processed to obtain plasma. The quantification of POPs in blood was carried out with an extraction technique with a focused ultrasound probe. Twenty-seven POP analytes were determined. The concentrations of hexachlorocyclohexane, endosulfan isomers, dichlorodiphenyltrichloroethane, total polychlorinated biphenyls, and the total sum of POPs found in plasma are higher than those reported in other studies, which reported effects such as hematological and biochemical changes in blood, changes in immune system cells and enzymatic activity related to oxidative stress. These results are important to demonstrate the chronic exposure to POPs in olive ridley turtles in marine ecosystems and to highlight the importance of assessing the associated health risks, considering that these contaminants could be transferred to the offspring and affect future generations of this reptile. It is important to carry out studies that develop conservation strategies for the olive ridley turtle. Also, it is necessary to control the emissions of pollutants into the atmosphere, as well as reduce urban, agricultural, and industrial waste in the environment and marine ecosystems.