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A fourteen-month monitoring period (April 2007-May 2008) was realized to investigate the removal and occurrence of eight pharmaceutical and personal care compounds, two metabolites and caffeine across the municipal wastewater treatment plant (WWTP) of Agrinio city, located in Western Greece as well as in the discharging sampling point in Acheloos River, which receives the effluents of the plant. Solid-phase extraction (SPE) was used for the isolation and pre-concentration of the target pollutants and gas chromatography mass spectrometry (GC-MS) for their detection and quantification. All the selected compounds were detected in the wastewater samples. The concentrations determined in the influent of the municipal WWTP ranged between 65.3 and 6679 ng L(-1) recorded for triclosan and caffeine respectively, while in the effluent ranged between 24.9 and 552 ng L(-1) observed for triclosan and carbamazepine, respectively. The detected concentration levels in Acheloos River ranged from 37.6 ng L(-1) for caffeine to 305 ng L(-1) for paracetamol. Mean total removal efficiencies ranged between 46.3% for carbamazepine and 96.8% for naproxen. The results of this study demonstrate that most of the compounds are being reduced in low levels by municipal wastewater treatment processes but quite significant levels of pharmaceuticals enter river waterways.

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BACKGROUND: The present study focuses on the photocatalytic transformation and mineralization of triclosan (TCS) using TiO 2 catalyst. The main objectives were: (a) to investigate the effect of TiO 2 , TCS concentration and irradiation intensity on the photocatalytic efficiency and to model the degradation and mineralization percentage of TCS using response surface methodology (RSM) based on central composite design (CCD); (b) to identify transformation products (TPs) and degradation mechanisms, (c) to assess the toxicity of the TPs. RESULTS: The results from the RSM analysis indicated that all operating parameters studied have significant effects on TCS degradation and mineralization. A quadratic response surface model was found to fit the experimental data and was used to find the optimum experimental conditions. Scavenging experiments indicated that HO • radicals were principally responsible for TCS degradation. The transformation of TCS involved reactions of mono-and di-hydroxylation, dechlorination, and cleavage of the ether bond. Total detoxification of the treated solution was obtained after 30 min, as revealed by Microtox bioassay. CONCLUSION: TCS can be effectively degraded and mineralized using TiO 2 under simulated solar light avoiding the formation of highly toxic TPs. RSM modeling provided a statistically accurate prediction of the optimum degradation and mineralization of TCS.