Target and non-target screening for the existence, ecological risk and source analysis of contaminants of emerging concern (CECs) in groundwater

Contaminants of emerging concern (CECs) are increasingly being discharged into the groundwater environment worldwide, causing a significant threat to human health and the environment. This study employed target, suspect and non-target screening methods based on high-resolution mass spectrometry (HRMS) to identify the risks and pollution sources of groundwater CECs in the Pearl River Delta region of China. 376 CECs were found through target and suspect screening from pollution sources such as agricultural, aquaculture, and domestic sources. The ecological risk assessment results revealed that the comprehensive CECs risk in groundwater is relatively high, and the characteristic compounds of CECs from aquaculture sources may pose a higher risk. The contribution of aquaculture source to groundwater reached a maximum of 43 %. Ponds, as sinks for various sources of contaminants, are more likely to interact with groundwater and pose a greater threat to groundwater. This study highlights the importance of comprehensive screening for the control of groundwater CECs and provides new ideas for subsequent monitoring and management strategies of groundwater CECs • Target and suspect screening identified 376 CECs in groundwater via LC-HRMS. • 84.2 % of the samples pose a comprehensive risk to the ecological environment. • Source characteristic CECs can identify high-risk points to a certain extent. • Source-specific fingerprints help quantify source contributions. • Aquaculture sources have a higher contribution (43 %) and risk (RQ, 0.965).