Inter- and intraspecific blood-related biomarkers and chemical exposure in confined and free-living sea turtles

12 pages, 4 figures, 2 tables, supplementary data https://doi.org/10.1016/j.envres.2024.120385.-- Data availability: Data will be made available on request

The relevance of recovery centers and head-starting programs for rescue, rehabilitation, rearing, and conservation of sea turtles is recognized worldwide. In addition, these centers contribute to generating biochemical and physiological data needed to identify health markers and provide baseline values. Because of the marine ecosystems’ deterioration, biomarker identification is a global priority for sea turtle conservation; nevertheless, information on specific endpoints, such as neurotoxicity and mutagenesis, is still limited in sea turtles. This study aimed to contrast a set of non-invasive blood biomarkers with ecotoxicological and clinical applications in confined green sea turtles (Chelonia mydas) compared with free-living ones from the Mexican Caribbean. Additionally, interspecific (green, hawksbill (Eretmochelys imbricata), loggerhead (Caretta caretta) turtles) differences were also evaluated. Plasmatic organochlorine pesticides (OCs) and polychlorinated biphenyl (PCBs) were also determined. The concentration ranges of uric acid, total proteins, lipids (cholesterol and triglycerides), and thyroxine of both confined and free-living green turtles fell outside the reference intervals for the species. Additionally, confined green turtles had the highest number of erythrocytic nuclear abnormalities (ENA) and elevated levels of hemoglobin, lipid peroxidation, and activity of glutathione S-transferase, glutathione peroxidase, and carboxylesterase (CE). Contrasts among confined species identified hawksbill turtles with the lowest glutathione reductase activity, green turtles with the lowest ENA frequency and CE activity, and loggerhead turtles with the highest plasmatic concentrations of PCBs and OCs. The information here provided can be used as information in health monitoring programs and for conservation and management policies at regional, national, and international level

This research was funded by CIBNOR (PC0.10), G. Espinosa Reyes (2019, Centro de Investigación Aplicada en Ambiente y Salud, Facultad de Medicina, CIACYT-UASLP) and VLM (Laboratorio Ecología de la Salud, Facultad de Ciencias, UASLP). [...] BLCC and CLR were recipients of graduate scholarships from CONACYT (1001718 and 931746, respectively). VLM, TZS, and MS collaboration was possible thanks to RIESCOS-CYTED (419RT0578). We thank the institutional support of Institut de Ciències del Mar, CSIC, and the ‘Severo Ochoa Centre of Excellence accreditation’ (CEX2019-000928-S funded by AEI 10.13039/501100011033)

Peer reviewed