Occurrence and fate of antibiotic, analgesic/anti-inflammatory, and antifungal compounds in five wastewater treatment processes

The presence of pharmaceuticals and personal care products (PPCPs) in the aquatic environment as a result of wastewater effluent discharge is a concern in many countries. In order to expand our understanding on the occurrence and fate of PPCPs during wastewater treatment processes, 62 antibiotic, analgesic/anti-inflammatory, and antifungal compounds were analyzed in 72 liquid and 24 biosolid samples from six wastewater treatment plants (WWTPs) during the summer and winter seasons of 2010-2012. This is the first scientific study to compare five different wastewater treatment processes: facultative and aerated lagoons, chemically-enhanced primary treatment, secondary activated sludge, and advanced biological nutrient removal. PPCPs were detected in all WWTP influents at median concentrations of 1.5 to 92,000 ng/L, with no seasonal differences. PPCPs were also found in all final effluents at median levels ranging from 3.6 to 4,200 ng/L with higher values during winter (p<0.05). Removal efficiencies ranged between -450% and 120%, depending on the compound, WWTP type, and season. Mass balance showed that the fate of analgesic/anti-inflammatory compounds was predominantly biodegradation during biological treatment, while antibiotics and antifungal compounds were more likely to sorb to sludge. However, some PPCPs remained soluble and were detected in effluent samples. Overall, this study highlighted the occurrence and behavior of a large set of PPCPs and determined how their removal is affected by environmental/operational factors in different WWTPs.