Evidence of accumulation and elimination of inorganic contaminants from the lachrymal salt glands of leatherback sea turtles (Dermochelys coriacea). (February 2019)

• Record Type: Journal Article
• Authors: Perrault, Justin R.; Lehner, Andreas F.; Buchweitz, John P.; Page-Karjian, Annie
• Is Part Of: Chemosphere. Volume 217(2019)
• Page Start: 59
• Page End: 67
• Publication Date: 2019-02
• Subjects: Blood -- Heavy metal -- Marine turtle -- Osmoregulation -- Salt gland secretion -- Toxicology; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2018.10.206
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Plasma osmolalities of marine vertebrates are generally lower than the surrounding medium; therefore, marine organisms must cope with the osmoregulatory challenges of life in a salty environment. The salt glands serve to maintain osmotic and ionic homeostasis in a number of lower marine vertebrates. One marine reptile, the leatherback sea turtle ( Dermochelys coriacea ), ingests excessive amounts of salts due to their diet of gelatinous zooplankton. Outside of the normal osmoregulatory function of the salt gland, little research has been conducted on contaminant accumulation and excretion in this organ. Here, we established arsenic, cadmium, lead, mercury, and selenium concentrations in red blood cells (RBCs) and salt gland secretions (SGSs) of nesting leatherbacks. We also collected salt glands from different life stage classes of dead stranded leatherbacks from the western Atlantic Ocean to determine if inorganic contaminants accumulate in this organ. Using non-metric multidimensional scaling and regression analyses, we determined that RBC and SGS inorganic contaminant concentrations were not correlated. Additionally, RBCs showed significantly higher concentrations of these contaminants in comparison to SGSs, likely due to the affinity of inorganic contaminants for the heme group of RBCs. Lastly, we found that salt gland cadmium and mercury concentrations tended to increase with increasing curved carapace length (CCL) in stranded leatherbacks. Our results indicate that different physiological mechanisms determine the distribution of inorganic contaminants in blood and SGSs. Increases in salt gland contaminant concentrations with increasing CCL suggest this organ as a potential target for accumulation. Graphical abstract: Highlights: RBCs and SGSs of nesting leatherbacks were analyzed for inorganic contaminants. Salt glands from stranded leatherbacks were analyzed for inorganic contaminants. RBCs showed higher concentrations of inorganic contaminants compared to SGSs. Inorganic contaminant concentrations in RBCs and SGSs were not correlated. Cadmium and mercury accumulate in the salt glands.