Occurrence and Risk Assessment of Targeted Pharmaceuticals Active Compounds in Drinking Water Treatment Plants at Shanghai, China

The Occurrence of nine selected pharmaceutically active compounds (PhACs), namely Paracetamol,Carbamazepine, Sulfamethoxazole, Pentoxifylline, Gemfibrozil, Diclofenac, Ibuprofen, Tetracyclineand Naproxen were investigated in influents and effluents of two drinking water treatment plants(DWTPs) across Shanghai, China. In addition, the removal of these compounds in both DWTPs withdifferentexisting technologies (DWTP-A: biofiltration process, activated carbon and ozonation;DWTP-B: sand filtration and coagulation, flocculation and sedimentation) was investigated.Theconcentrations of these compounds in the influents from the two DWTPs showed substantialvariations with average concentrations ranging from 3.24ng L-1for Tetracycline to 62.3ng L-1forGemfibrozil, while Naproxen and Carbamazepine were found in effluents with averageconcentration of 0.26 ng L-1and 1.53 ng L-1, respectively. The risk assessment based on the „„worstcasescenario‟‟ of the monitoring data from the influents of the present study suggested thatDiclofenac and Sulfamethoxazole could pose a medium risk to the aquatic organisms while othercompounds showed no potential toxic risks to aquatic organisms. A screening level risk assessmentimplied that the concentrations of the detected PhACs are well below levels that would pose a risk tothe health of consumers of drinking water at Shanghai, China. Biodegradation using ozone wasfound to be the most effective mechanism for removing concentrations of PhACs, while filtrationappeared to be a minor process for removing all PhACs.

Keywords:

Aquatic organisms , Drinking water , Pharmaceutical active compounds , Risk assessment , Water treatment