Occurrence of pharmaceuticals, illicit drugs, and resistant types of bacteria in hospital effluent and their effective degradation by boron-doped diamond electrodes

摘要

Wastewaters are considered as a significant source of pathogenic microorganisms and a wide spectrum of pharmaceuticals. Disinfecting agents and antibiotics in these wastewaters can directly or indirectly influence the genetic composition of the present microorganisms and thus the occurrence of bacteria resistant to antibiotics. In this study, we have investigated the composition of wastewaters from two Slovak and one Czech hospital. Using in-line solid phase extraction liquid chromatography coupled with tandem mass spectrometry (in-line-SPE-LC-MS/MS), we monitored the occurrence of 29 pharmaceuticals, illegal drugs and their metabolites and resistant types of microorganisms. It was found that cotinine (max 1980 ng/dm(3)), tramadol (max 1570 ng/dm(3)), venlafaxine (max 248 ng/dm(3)), codeine (max 136 ng/dm(3)), oxazepam (max 113 ng/dm(3)), and oxycodone (max 102 ng/dm(3)) belong to the group of the most concentrated compounds. The number of coliform bacteria ranged from 5.5 to 7 log CFU/cm(3), while majority of strains were ampicillin, gentamicin, and ciprofloxacin resistant. The number of Staphylococcus aureus was lower (2.7-3.8 log CFU/cm(3)), with predominance of ampicillin and penicillin resistants. In the next part of the study, the possibility of the application of boron-doped diamond (BDD) electrodes connected as anode for hospital wastewaters treatment was investigated. The obtained results indicate that the BDD anode is able to degrade a large scale of analyzed pharmaceuticals and drugs occurred in wastewaters with more than 60 % efficiency in 30 min.