Abstract:To investigate the pollution level, distribution characteristic and ecological risk of psychotropic substances and their metabolites in Lakes Gaoyou, Baoying and Shaobo, Jiangsu Province, 18 water samples were collected. The concentrations of 21 psychotropic drugs and their metabolites in three classes:antidepressants, antiepileptics and antipsychotics were analyzed by ultra- high-performance liquid chromatography- triple quadrupole tandem mass spectrometry. The results indicated, in addition to oxcarbazepine, 20 typical drugs and their metabolites were detected at 18 sampling sites with the detection rates of 22.2%-100%, and the total concentration ranged from 1.4 to 224.5 ng/L. Among the detected substances, the concentration of risperidone (0.1-64.1 ng/L) was the highest. Spatial differences in the concentrations of psychotropic substances and their metabolites existed at different sampling sites, showing a trend of higher concentrations in Lake Shaobo and the southern part of Lake Gaoyou and lower concentrations in the northern part of Lakes Gaoyou and Baoying. The cluster analysis showed that point S1 and S7 formed separate clusters with concentrations of 175.7 ng/L and 102.9 ng/L, respectively. The source analysis found that wastewater treatment plants, domestic sewage and agriculture discharge may be the principal sources of the psychotropic substances and their metabolites. The risk quotient method showed that the RQ values for carbamazepine and oxcarbazepine were greater than 1 and were of high risk to aquatic organisms. The risk of psychotropic substances and their metabolites in the environment still needs attention.