Assessing the Effect of a Newly Implemented Basic Wastewater Discharge Standard on the Concentrations of Pharmaceutical and Personal Care Products in the Daqing River Basin, China

Wastewater discharge standards often play a crucial role in water environmental management. However, most of these standards only focus on conventional water pollutants such as chemical oxygen demand (COD), 5-day biochemical oxygen demand (BOD5), ammonia (NH3-N), total nitrogen (TN), and total phosphorus (TP). It is unclear if there is an impact on the removal of pharmaceuticals and personal care products (PPCPs). The Daqing River Basin is an important water system in China. In 2018, a new wastewater discharge standard for the Daqing River Basin (DB 13/2795-2018) was issued, which mainly limits the discharge of conventional water pollutants, including COD (20-40 mg L-1), BOD5 (4-10 mg L-1), NH3-N (1-2 mg L-1), TN (10-15 mg L-1), and TP (0.2-0.4 mg L-1). Herein, we evaluated the performance of the new wastewater discharge standard, especially the effect on the removal of PPCPs. We characterized the occurrence of PPCPs and the resulting ecological impact in the basin, and compared the occurrence of PPCPs before (2017) and after (2021) implementation of the standard. A total of 16 PPCPs were detected, of which diclofenac, carbamazepine, ibuprofen, and bezafibrate pose risks to crustaceans and fish in the basin. A positive impact from the implemented standard, on the removal of some PPCPs, was confirmed, especially for lincomycin and trimethoprim.