Fate and removal of pharmaceuticals and illegal drugs present in drinking water and wastewater

Abstract

Rapid development of pharmaceutical industry, and thus widespread availability of different types of therapeutical and increased intake of pharmaceuticals, results in elevated concentrations of pharmaceuticals in municipal wastewater subjected to treatment in wastewater treatment plants. Pharmaceuticals present in raw wastewater discharged from hospitals, households, veterinary and health care clinics eventually end up in wastewater treatment plants. Commonly applied methods for treating wastewater do not allow complete removal of these contaminants. As a consequence, pharmaceuticals still present in treated wastewater are introduced to water environment. The most frequently identified pharmaceuticals in surface water belong to the following groups: non steroidal anti inflammatory drugs, beta-blockers, estrogens and lipid regulators. The most difficult is removal of diclofenac, clofibric acid and carbamazepine as these substances show low biodegradability. Diclofenac can be removed in the process of wastewater treatment by 40%, carbamazepine by 10%, and clofibric acid from 26 to 50%. The presence of diclofenac sodium in the rivers in Poland was confirmed and the concentrations were following: 380 ng/dm3 (the Warta river), 470 ng/dm3 (the Odra river), 140 ng/dm3 (the Vistula river). Naproxene was found in the Warta river at the concentration of 100 ng/dm3. The presence of pharmaceuticals in surface water can be toxic to aqueous microorganisms and fish. Recent studies confirmed also the presence of pharmaceuticals in drinking water. This is considered as a problem especially in urban agglomerations such as Berlin or large cities in Spain and China. The studies showed that pharmaceuticals were also identified in the samples taken from the Polish rivers and drinking water. The presence of naproxene and diclofenac at the concentrations of 13 and 4 ng/dm3 was identified in drinking water sampled from water intakes in Poznan. Surface water and drinking water showed also the presence of illegal drugs.