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Pharmaceuticals and personal care products (PPCPs) are becoming increasingly recognised as important micropollutants to be monitored in wastewater treatment plants (WWTPs), since WWTP effluents represent an important point source to natural aquatic systems. In this study, the abundance of 65 PPCPs was analysed in 5 Portuguese WWTPs during the spring and autumn. Due to the fact that analytical approaches normally used to quantify the abundance of these compounds are labour intensive and require various specific procedures, this study proposes a set of simplified analytical methods for the quantification of pharmaceutically active compounds (PhACs) and polycyclic musks in liquid and sludge samples. The analytical methods were validated using influent wastewater matrices, showing comparable limits of detection and quantification as literature values for most PPCPs, with the exception of the estrogenic compounds. The PhAC concentrations detected in the WWTP survey were in the range of 0.050-100 µg L(-1) in the influent and up to 50 µg L(-1) in the effluent, where the non-steroidal anti-inflammatory drugs (NSAIDs) were the most abundant and frequently detected group. Some musks were detected up to 11.5 µg L(-1) in the influent and 0.9 µg L(-1) in the effluent, and adsorbed in the sludge up to 22.6 µg g(-1).

The main removal mechanism of PhACs and musks studied in the WWTP was most often biological (45%), followed by adsorption (33%) and by UV radiation (22%). In the majority of the cases, the WWTP achieved>75% removal of the most detected PhACs and musks, with the exception of diclofenac.

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Ibuprofen (IBU) is a non-steroidal anti-inflammatory drug that is becoming increasingly recognized as an important micropollutant to be monitored in wastewater treatment plants (WWTP), since it has been detected in effluents at the µg L level. The IBU metabolites from biological degradation are not completely understood and can represent a threat to natural aquatic systems. P. medicamentivorans was previously isolated from WWTP sludge and found to be capable of IBU degradation. The aerobic biodegradation of ibuprofen by this organism was investigated in a batch lab-scale reactor for the identification of the metabolites formed. The metabolites were analysed and putatively identified by HPLC-DAD-MS/MS and GC-MS and biodegradation pathways were proposed. The toxicity and the biodegradability potential of the metabolites were also investigated. The results showed that IBU biotransformation was achieved by hydroxylation followed by the formation of a carboxylic acid in the IBU molecule and by the formation of a catechol, allowing the aromatic ring cleavage. Two biodegradation pathways were proposed: in one, the metabolites generated from the enzymatic action correspond to a less biodegradable chemical structure of the intermediate products (isobutylbenzene and 3-isobutylphenol), with comparatively higher toxicity; in the other mechanism, more oxidable chemical structures were formed with less toxicity and higher biodegradability. This suggests that the biodegradation of IBU by P. medicamentivorans can take place by more than one mechanism regarding the enzymes formed by this Gram-positive bacterium, with subsequent oxidation of the parent compound to overall more soluble and less toxic compounds to fish, daphnia and green algae.

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