Summary:
The pharmaceutical residues is an issue of great concern to the scientific
community over the last decade, due to the fact that they are not completely
metabolized by the body, thus excreted mostly as parent or conjugated compounds
or minor metabolites. The urban wastewater is an important stream for the
transfer to the aqueous and terrestrial environment and their presence raises
concerns.
This study focuses in the determination of 89 pharmaceutical compounds (e.g.
cefalosporines, NSAIDs, macrolides) with LC-MS/MS in samples of Psitalia WWTP.
40 of them (45%) were detected in all the samples of influents wastewater e.g.
cephalosporins (100% detection), penicillin (100%), NSAIDs. The higher
concentrations in the influents were observed for: Metformin, Atenolol etc.
There was considerable variation per day, but there is no clear correlation.
Regarding the primary/secondary treatment, 33 substances were removed, 15 with
a rate of higher than 80%: Simvastatin, Sulfadiazine, Cortisone and Cefaclor
(100%) while 23 showed higher concentrations in the effluents compared to the
influents due to their formation in treatment tanks. In addition, experiments
were tertiary treatment (e.g. UV, PAC) indicating that with PAC the removal
rate is >10% of the 43 compounds.
Also, the average daily mass load to the aquatic environment was calculated
with the highest being for: Metformin, Acetylsalicylic acid, Paracetamol, with
average daily masses: 1,82 kg/d, 1,79 kg/d, 1,42 kg/d respectively. Finally, RQ
and RQmix were estimated for all the compounds. Only Carbamazepine had RQ > 1.
Due to the fact that the receiver is an open sea and RQmix < 1 there is no
significant ecological risk.
Keywords:
Pharmaceutical compounds., Risk assessment, LC/MS-MS, WWTP of Psitalia, Emerging contaminants of concern
