Wastewater surveillance for chronic disease drugs in wastewater treatment plants: Mass load, removal, and sewage epidemiology

As the number of chronic disease patients continues to climb, vast quantities of chronic disease drugs are continuously discharged into the wastewater treatment plants (WWTPs) and then are released to the receiving environment. However, the situations of pollution, removal, and consumption of chronic disease drugs in China were not studied. Here we investigated the mass load and removal efficiency of 14 chronic disease drugs in seven wastewater treatment plants (WWTPs) of Guangdong Province, China, and estimated the proportional usage of chronic disease drugs and the prevalence of chronic diseases by wastewater-based epidemiology (WBE) method. The results showed that all target chronic disease drugs were detected in the WWTPs, among which gliclazide, valsartan, and bezafibrate were the mainly detected antidiabetic drug, antihypertensive drug, and antihyperlipidemic drug, respectively. The aqueous removal rates of chronic disease drugs ranged from -163 %-100 % in studied WWTPs, and most chronic disease drugs were mainly removed at anaerobic stage in WWTPs that using Anaerobic-Anoxic-Oxic treatment technologies. Mean mass loads of chronic disease drugs in the influent of seven WWTPs ranged at 72-318099 mg·d^-1 (valsartan), and mean emission of chronic disease drugs in seven WWTPs ranged at 0-56.3 mg·d^-1·1000 inhabitant^-1 (valsartan). Based on the WBE method, the prevalence of diabetes, hypertension, and dyslipidemia estimated by gliclazide, glipizide, valsartan, and bezafibrate in this study was consistent with those obtained via cross-sectional survey. The results formulated the contamination characteristics of chronic disease drugs in China and assessed the accuracy of chronic disease drugs used for disease prevalence estimation.