Seasonal occurrence and source analysis of pharmaceutically active compounds (PhACs) in aquatic environment in a small and medium-sized city, China

Pharmaceutically active compounds (PhACs) have been widely reported in most megaci ties in China but seldom in small and median-sized cities. The aim of this study is to investigate occurrence and distribution characteristics of PhACs in a typical small and medium-sized city in China and analyze their sources. 33 PhACs and 4 chiral drugs were selected for a four-season monitoring campaign in Wujin District Jiangsu Province, a typical small and median-sized city, in 2018. PhACs concentration level in surface water, ranging from ng L-1 to mu g L-1, was lower than in large-sized cities and areas in China. Impact from agricultural sources should be concerned in the study area: (1) Significant correlation between concentrations of antibiotics and NH4-N in surface water indicated the potential impact from agricultural sources (fishponds and livestock farms); (2) Government regulating measures on livestock and poultry farms since January 2018 have effectively decreased macrolides and lincosamides emissions into surface water. As for source analysis, CF/CBZ (Caffeine/Carbarnazepine) was a feasible indicator to trace untreated wastewater and enantiorrieric fraction values of metoprolol (MTP) were also suggested to be helpful for identifying untreated wastewater. The results of both two indicators indicated more input of untreated wastewater to surface water in the northeast area and upstream of Wuyi Canal. To our best knowl- edge, this is the first study to systematically analyze PhACs in aquatic environment for a small and medium-sized city in China. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

Pharmaceutically active compounds (PhACs) have been found in most megacities in China but rarely in small and medium-sized cities. This study investigated the occurrence and distribution of PhACs in a typical small and medium-sized city in China, revealing lower levels in surface water compared to larger cities. Agricultural sources were identified as a concern, with indicators showing more untreated wastewater input in certain areas.