Environmental Impact of Phthalates on Adult Sea Turtles and Eggs in the Mediterranean Sea

Abstract

Plastic pollution poses a global threat, especially to marine ecosystems and their inhabi-tants. Many species, including sea turtles, have been observed ingesting plastic debris, leading to chemical contamination from lipophilic plastic components like phthalic acid esters (PAEs) [1]. The plastic's extended residence time in the gut can cause chemical contamination of the organism. This is due to the bioaccumulation of lipophilic plastic constituents, such as phthalic acid esters (PAEs) [1]. PAEs are organic pollutants that are of growing concern due to their harmful effects on hormonal balance. They act as active substances at the endocrine level [2]. Despite current restrictions on the use of phthalates as additives, natural biosynthesis of PAEs by different organisms could contribute to increased environmental contamination, resulting in their ubiquitous presence [2]. The aim of this research is to enhance understanding of the impact of these substances on sea turtles. The levels of six phthalates, which are commonly used as additives, were determined in various tissues and unhatched eggs of sea turtles. We aimed to verify the presence and biodistribution of PAEs in the yolks, albumens, and eggshells, investigating the origin of contamination [3]. The HPLC/MS analyses revealed high levels of the most lipophilic phthalates in gonadal and liver samples of C. caretta and Dermochelis coriacea [1]. Additionally, although to a lesser extent, high levels of contamination were also detected in the eggs of C. caretta [3]. Statistical analysis confirmed significant differences in the biodistribution of each phthalate and their sum between the eggshell, yolk, and egg albumen [3]. In relation to the sources of contamination, it is our opinion that phthalates in eggs originate from the mother, specifically from the release of phthalates during the digestive process [3]. This hypothesis, which is supported by other studies, is further reinforced by preliminary tests carried out on eggshells. As a final remark, the distribution of different phthalates among tissues allows for the interpretation of the impact that the metabolic pathways of these substances may have on marine organisms. In general, the negative effects of bioactive and ubiquitous pollutants dispersed in marine ecosystems require continuous monitoring to assess their geographical and biological distribution, particularly within endangered species, to support environmental policies and regulations. Acknowledgements Funder: Project funded under the National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.4 - Call for tender No. 3138 of 16 December 2021, rectified by Decree n.3175 of 18 December 2021 of Italian Ministry of University and Research funded by the European Union – NextGenerationEU; Award Number: Project code CN_00000033, Concession Decree No. 1034 of 17 June 2022 adopted by the Italian Ministry of University and Research, CUP B73C22000790001, Project title “National Biodiversity Future Center - NBFC”. References [1] Savoca, D., Arculeo, M., Barreca, S., Buscemi, S., Caracappa, S., Gentile, A., ... & Pace, A. (2018). Chasing phthalates in tissues of marine turtles from the Mediterranean sea. Marine pollution bulletin, 127, 165-169. [2] Savoca, D., Barreca, S., Lo Coco, R., Punginelli, D., Orecchio, S., & Maccotta, A. (2023). Environmental Aspect Concerning Phthalates Contamination: Analytical Approaches and Assessment of Biomonitoring in the Aquatic Environment. Environments, 10(6), 99. [3] Savoca, D., Arculeo, M., Vecchioni, L., Cambera, I., Visconti, G., Melfi, R., ... & Pace, A. (2021). Can phthalates move into the eggs of the loggerhead sea turtle Caretta caretta? The case of the nests on the Linosa Island in the Mediterranean Sea. Marine Pollution Bulletin, 168, 112395.