Occurrence of carbamazepine and five metabolites in an urban aquifer

This paper deals with urban groundwater contaminated with carbamazepine (CBZ) and five of its human metabolites in Barcelona. Groundwater samples were accordingly collected in the aquifers of Poble Sec and Besos River Delta. Higher concentrations and more compounds were found in the Besos River Delta aquifer, which is recharged by a river contaminated with treated effluent from numerous treatment plants. By contrast, the urban area of Poble Sec presented lower concentrations and fewer compounds. The results showed that CBZ could be attenuated in the Poble Sec aquifer since concentrations in groundwater were lower than those evaluated from mixing of the recharge sources. Conversely, CBZ and its human metabolites were not removed under the reducing conditions of the Besos River Delta aquifer probably because of the short residence time in this aquifer. (C) 2014 Elsevier Ltd. All rights reserved.