[Temporal and Spatial Occurrence of NSAIDs in Taihu Lake and Relevant Risk Assessment].

Non-steroidal anti-inflammatory drugs (NSAIDs) are a class of drug residues with a high frequency of detection in Taihu Lake. However, little information is available about the occurrence of typical NSAID mixtures in Taihu Lake as a whole across the four seasons. Therefore, for each season, the concentrations of five typical NSAIDs including diclofenac, ibuprofen, indomethacin, naproxen, and ketoprofen were monitored in the water of Taihu Lake by the method of high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) at 19 transects covering the entire lake. The temporal and spatial occurrence of NSAID mixtures in the water of Taihu Lake and their correlation with environmental factors were analyzed, and the mixture risk quotient (MRQ) model was also used to assess the ecological risk of the NSAID mixtures. The research results are as follows:① The concentrations of NSAIDs in the northern, western, and eastern waters of Taihu Lake are at a higher level compared to those in the central waters. Ketoprofen is the main contributor to the contamination of NSAID mixtures in all regions of Taihu Lake. ② The concentrations of NSAIDs in Taihu Lake are higher in summer (15.9-134.3 ng·L