Exploring contaminants as a disruptor of temperature-dependent sex determination in sea turtle hatchlings

Title	Exploring contaminants as a disruptor of temperature-dependent sex determination in sea turtle hatchlings
Authors	Arthur D. Barraza, Larissa Young, Caitlin E. Smith, David T. Booth, Christine A. Madden Hof, Kimberly A. Finlayson, Frederic D. L. Leusch, Jason P. van de Merwe
Magazine	Frontiers in Marine Science
Date	11/13/2023
DOI	10.3389/fmars.2023.1238837
Introduction	Sea turtle nesting sites face rising sand temperatures due to ongoing climate change, leading to a severe sex imbalance where over 99% of green turtle hatchlings in certain regions are female. The influence of environmental contaminants on sea turtle hatchling sex determination warrants further investigation. This study involved collecting liver samples from green turtle hatchlings, which were then subjected to histological sex determination. These samples underwent analysis for trace elements using acid digestion and for organic contaminants through in vitro cytotoxicity bioassays. Elements such as chromium, antimony, barium, and cadmium are known for their oestrogenic properties. Their concentrations were utilised to compute three oestrogenic indices per clutch: predicted relative oestrogenic potency (PEEQA), the sum of percent trace elements above the median (TEOM), and the sum of percent oestrogenic elements above the median (EstroEOM). Results indicated that, with one clutch excluded as an outlier, cadmium, antimony, and EstroEOM exhibited significant positive correlations with sex ratio deviation. Additionally, average clutch concentrations of cobalt, lead, antimony, and barium showed a significant positive link with clutch sex ratio. While in vitro cytotoxicity of liver extracts did not correlate with sex ratio, 9% of hatchlings presented organic contaminant levels indicative of potential cellular harm. The impact of contaminants on sex determination likely stems from complex interactions among contaminants and with temperature. Several trace elements identified in this research have been associated with adverse health outcomes in hatchlings in prior investigations. Given the threats of feminisation from climate change and the potential effects of contaminants on hatchling well-being and sex determination, further research into contaminant impacts on sea turtle hatchling sex determination is advisable.
Quote	Arthur D. Barraza, Larissa Young and Caitlin E. Smith et al. Exploring contaminants as a disruptor of temperature-dependent sex determination in sea turtle hatchlings. Front. Mar. Sci.. 2023. Vol. 10. DOI: 10.3389/fmars.2023.1238837
Element	Antimony (Sb) , Barium (Ba) , Chromium (Cr) , Cobalt (Co)
Industry	Research & Laboratory , Chemical & Pharmacy