First report on the occurrence of potentially toxic elements in coastal zones of the Cayos Cochinos Archipelago, Honduras

Abstract

This first comprehensive report examines the spatial distribution and concentration of potentially toxic elements (PTE) in intertidal and supratidal zones across five islands of the Cayos Cochinos Archipelago, a marine protected area within the Meso-American Barrier Reef, Caribbean Sea. Seventy-five sand samples were collected during December 2022 and analyzed for chromium (Cr), cobalt (Co), zinc (Zn), arsenic (As), cadmium (Cd), lead (Pb), copper (Cu), and nickel (Ni) using inductively coupled plasma-optical spectrometry. The islets with the highest anthropogenic pressure exhibited the highest levels of As, Pb, Ni, Co, Cu, Zn, Cr, and Cd. Significant spatial variations in PTE-concentrations were observed among sampling locations, with the supratidal zone generally showing higher PTE accumulation than those levels of the intertidal zone, excepting Pb with the highest levels (25.44 µg g⁻¹ d.w.) in sands of the intertidal zone. The toxicity of PTEs can have significant consequences for aquatic organisms in these delicate ecosystems, and can disrupt food chains through bioaccumulation. Future investigations should focus on expanded elemental analysis, and comprehensive ecological risk assessments to better understand the long-term environmental routes of toxic elements in fragile coastal marine areas.