RETRACTED: Ecological risk assessment and prioritization of contaminants of emerging concern in the Upper Yangtze River, Chongqing, China
Abstract
• 156 CECs detected, 64 newly identified in Chongqing’s surface waters. • High ecological risks found for 48 CECs, including methamphetamine. • Carcinogenic risks exceeded thresholds for neonicotinoids, antidepressants. • Multi-criteria model prioritised 26 high-risk pollutants for regulation. • Urgent need for region-specific CEC monitoring and policy action. The widespread presence of Contaminants of Emerging Concern (CECs) in freshwater systems poses a growing ecological and public health threat, particularly in rapidly urbanising regions where traditional monitoring overlooks non-conventional pollutants. This study aims to systematically assess the occurrence, ecological and health risks, and prioritization of CECs in the Upper Yangtze River, with a focus on the Chongqing Municipality—including the core urban districts of Yuzhong and Jiangbei—over two hydrological seasons in 2023. A total of 27 surface water samples were collected from 10 drinking water sources and two major tributaries (Jialing and Wujiang Rivers), and analyzed through an integrated approach combining target screening, suspect screening using LC-QTOF-MS, risk quotient (RQ) assessment, and a multi-criteria prioritization model. Out of 162 targeted CECs, 156 were detected with concentrations ranging from 0.01 to 2218.2 ng/L, while 64 additional compounds were identified for the first time in this region, including novel pharmaceuticals and industrial chemicals. High ecological risk (RQ > 0.1) was observed for 48 CECs, with methamphetamine, triclocarban, imidacloprid, and sertraline posing the greatest ecological hazards. Despite low non-carcinogenic health risks, carcinogenic risks associated with neonicotinoids and antidepressants exceeded acceptable thresholds in adults. The multi-criteria prioritization framework identified 26 high-priority pollutants, dominated by antibiotics (23 %), organophosphate esters (19 %), and personal care products (15 %). This study highlights the urgent need for region-specific regulatory action to routinely monitor and manage emerging contaminants in ecologically sensitive drinking water basins such as the Upper Yangtze River.