Abstract
The Day River is an important freshwater resource in the Red River Delta, an important economic region of Vietnam. This paper presents an ecological risk assessment of 22 pharmaceutical residues in the Day River in the dry and rainy seasons in 2023. Total concentrations of 22 pharmaceuticals (Azithromycin-AZI, Carbamazepine-CBZ, Cefotaxime-CTX, Cephalexin-CLX, Ceftiofur-CTF, Chlortetracycline-CTC, Ciprofloxacin-CIP, Clarithromycin-CLA, Doxycycline-DOX, Enrofloxacin-ENR, Erythromycin-ERY, Levofloxacin-LEV, Moxifloxacin-MFX, Norfloxacin-NOR, Ofloxacin-OFL, Oxytetracycline-OTC, Roxithromycin-ROX, Sotalol-SOL, Spiramycin-SPI, Sulfamethoxazole-SMX, Tetracycline-TET, and Trimethoprim-TRI), varied from 1.2 to 237.4 (mean = 33.8) ng.L−1. Of the 22 pharmaceuticals investigated, 14 were detected, of which SMX had the highest concentration (24.3 ng.L−1) and most frequent detection (69%). The potential ecological risk for algae, microbes and invertebrates revealed that only CLA exhibits a ‘high potential risk’ for algae whereas all other pharmaceuticals were classed as having ‘negligible adverse effects’. Seasonal variation of pharmaceutical concentrations and their relationship with water quality revealed that five pharmaceuticals (NOR, CTX, CIP, CLX, and SOL) probably originate from point sources whereas eight others (SMX, AZI, ERY, CLA, ROX, CBZ, TRI and LEV) are from diffuse sources in the watershed. The implications of these results plead for setting up of regular monitoring of pharmaceutical residues in this economically important river basin.
Recommended citation
Thi Mai Huong Nguyen, Nhu Da Le, Van Hoi Bui, Cam Tu Vu, Thi Thu Ha Hoang, Thi Xuan Binh Phung, Emma Rochelle-Newall, Thi Thanh Huyen Dinh, Thi Huong Vu, Thi Thuy Duong, Tien Dat Nguyen, Thi Mai Huong Pham & Thi Phuong Quynh Le (27 Nov 2024): Spatial distribution and ecological risk of pharmaceutical residues in the Day River, Vietnam, International Journal of Environmental Analytical Chemistry, DOI: 10.1080/03067319.2024.2433187 (SCIE, IF = 2.3, Q2, ISSN: 0306-7319).
