Occurrence and ecological risk of pharmaceuticals and personal care products in Djibouti's coastal waters.

Pharmaceuticals and personal care products (PPCPs) are recognized as emerging organic contaminants in marine environments and have gained worldwide attention. The aim of this study is to investigate for the first time, the occurrence, and potential ecological risks of PPCPs in the Djibouti's coastal waters. 25 PPCPs from 11 therapeutic groups of human and veterinary medicine were sought in water samples collected from 7 stations in the Gulf of Tadjourah and three estimation approaches (mRQMEC/PNEC, mRQSTU, MCR) were explored to assess ecological risks to aquatic life. 16 out of the 25 PPCPs belonging to 5 human therapeutic classes (analgesic-anti-inflammatory, antibiotic, stimulant, topical analgesic, and antiepileptic) were detected in the Djiboutian coastal water samples, with concentrations ranging from 2.29 to 684.75 ng/L. To our knowledge, levofloxacin and capsaicin presence were confirmed for the first time in Djibouti coastal waters, indicating an additional risk to aquatic biota. Most offshore sites (M3, M4 and M5) exceeded the risk threshold based on sensitive mRQMEC/PNEC approach with RQ values higher than 145, 657 and 155, respectively. This result was mainly attributed to the detection of ibuprofen, carbamazepine, and caffeine at high levels. Station M4, the most polluted, is characterized by the direct discharge of untreated urban and hospital wastewater onto the coastline, notably from the unique Djiboutian tuberculosis treatment center. This work would contribute to future research on the Gulf Aden and East Africa coast and help to implement environmental policies related to PPCPs on the East Africa coast.