Water Research 36 (2002) 2869–2877 Carbamazepine in water: persistence in the environment, ozonation treatment and preliminary assessment on algal toxicity Roberto Andreozzi a, *, Raffaele Marotta a , Gabriele Pinto b , Antonino Pollio b a Dipartimento di Ingegneria Chimica, Facolta di Ingegneria Chimica, Universita degli Studi di Napoli ‘‘Federico II’’, P. le V. Tecchio, 80-80125 Napoli, Italy b Dipartimento di Biologia Vegetale, Facolta di Scienze, Universita. degli Studi di Napoli ‘‘Federico II’’, via Foria, 223-80139 Napoli, Italy Received 10 January 2001; accepted 19 October 2001 Abstract The presence of carbamazepine (CBZ), an antiepilectic drug, has been reported in sewage treatment plant (STP) effluents as a result of its low biodegradability. In the present work, the persistence of CBZ in aquatic environment with respect to abiotic transformation processes along with its toxicity and capability of accumulating in single aquatic organisms (algae) are evaluated. The possibility of removing CBZ from STP effluents is studied by characterizing its ozonation process through the assessment of kinetics and the distribution of oxidation products. r 2002 Elsevier Science Ltd. All rights reserved. Keywords: CBZ; Photodegradation; Ozonation; Drugs; Surface water; Algal bioassay 1. Introduction The presence of pharmaceutical compounds in river and surface waters has been frequently reported in the last years [1–5]. Veterinary and human use are generally recognized as the most relevant sources for this new class of environmental pollutants [6]. In fact many of the numerous active substances used to treat illnesses are excreted unmetabolised or as active metabolites. More- over, improper disposal of expired medications can contribute to the contamination of the environment. Particularly, it has been reported in Germany the presence of up to 32 drugs in the influents to Municipal Sewage Treatment Plants [7]. Some of these compounds are only partly removed in conventional biological treatments since they are found at significant concentra- tions in STP effluents and therefore in surface waters. Whether the presence of these compounds in the environment may be harmful for man and living organisms is still under debate. In fact, although these substances have the capability of causing biological effects, no indications are found in the literature about their persistence in the environment after the dicharge and the real interactions they have with living organisms at the concentrations at which they are found in surface waters. With the reference to the persistence, it has been reported that some pollutants may undergo photoche- mical transformations, via direct light absorption or sensitized reactions [8,9] through which their character- istics can be modified. Only scant indications are found on their removal from wastewaters [10]. Carbamazepine (CBZ) is an antiepileptic drug whose occurrence in municipal STP effluents and in domestic wastewaters has been reported in the literature [7,11]. No indications are available in specialized journals for its persistence in the environment and/or for its toxicity *Corresponding author. Tel.: +39-081-768-2251; fax: +39- 81-593-6936. E-mail address: andreo@irc.na.cnr.it (R. Andreozzi). 0043-1354/02/$-see front matter r 2002 Elsevier Science Ltd. All rights reserved. PII:S0043-1354(01)00500-0