Widespread bioaccumulation of contaminants of emerging concern in Red Sea coral reefs: Evidence from Pocillopora favosa

by Margarida Branco, Mariana Rodrigues, Micaela S.S. Justo, João Cúrdia, Geert-Jan Witkamp, Andreia Farinha, Susana Carvalho
Research article Year: 2026 DOI: https://doi.org/10.1016/j.marpolbul.2026.119458

Abstract

Coral reefs are increasingly threatened by multiple stressors, including contamination from pharmaceuticals and personal care products, collectively known as contaminants of emerging concern (CECs). This study investigated the occurrence, distribution, and bioaccumulation factors of 10 CECs in the coral Pocillopora favosa across 15 reefs in three central Red Sea regions (Thuwal, Jeddah, Al Lith) spanning a gradient of human pressure. Using SPE and HPLC-MS, CECs from different classes (antibiotics, anti-inflammatories, bronchodilator, central nervous system agents, stimulant, and herbicide) were quantified in coral tissues and seawater. Most CECs were detected in both matrices, with salbutamol and atrazine showing the highest detection frequencies. Bioaccumulation factors indicated uptake of most compounds except caffeine, tramadol, and ranitidine throughout the regions. Unexpectedly, some CECs exhibited higher concentrations offshore than neashore, suggesting complex transport and bioaccumulation dynamics. Results reveal widespread presence of CECs in Red Sea corals and the need for pollution mitigation strategies.

Keywords

Red sea coral reefs Organic contamination Pharmaceuticals and personal care products Bioaccumulation SPE HPLC-MS