Barra Caracciolo A., Patrolecco L., Di Lenola M., Battaglia A., Grenni P., 2012, Degradation of Emerging Pollutants in Aquatic Ecosystems, Chemical Engineering Transactions, 28, 37-42.
The present work aims to define the natural attenuation potential of a river ecosystem versus Naproxen and Gemfibrozil pharmaceutical contaminants, evaluating the role of the autochthonous bacterial community in their degradation. The biotic degradation (DT50) of Naproxen and Gemfibrozil were evaluated in microbiologically active versus sterilized river water, using laboratory microcosms. Moreover, the degradations of Naproxen was also evaluated in microcosms simultaneously treated with both pharmaceuticals in order to evaluate if their co-presence could affect their environmental fate and the degradation activity of the microbial community. Each pharmaceutical was added at a concentration of 100 µg/L. Chemical analyses were performed using a HPLC-Fluorescence method recently validated in order to follow the decrease of the pharmaceuticals in microcosms. The number of live bacteria (N. live bacteria/mL) both in pharmaceutical treated and un-treated river water was also evaluated using epifluorescence microscopy. The overall results show that no decrease in pharmaceutical concentrations was observed in the sterile water, while the bacterial community had a key role in their degradation Naproxen was in fact completely degraded after about 30 days both when alone and in co-presence of Gemfibrozil. Gemfibrozil was partially degraded and 64 % of its initial concentration is still present at day 105.
