Quantitatively removing trace levels of contaminant antibiotics from our wastewaters is an important step towards preventing the alarming current spread of antibiotic-resistance in pathogenic bacteria. As standard primary and secondary treatment systems have been demonstrated to be inadequate, additional treatments such as Advanced Oxidation Processes (AOPs) are now being considered for large-scale systems. These treatments use generated hydroxyl radicals (●OH) to destroy these contaminant chemicals remaining after conventional treatment. The AOP treatment of antibiotic-contaminated waters has shown that the removal of these pharmaceuticals can be effective and quantifiable. However, simply oxidizing the β-lactam antibiotics by its reaction with a hydroxyl radical does not necessarily remove all its anti-bacterial properties. Therefore, to determine the true extent of treatment required to completely remove antibiotic activity from different quality waters, in this study we have used <sup>137</sup>Cs gamma radiation to quantitatively create hydroxyl radicals in antibiotic solutions plus a cell proliferation assay to measure the effectiveness of the oxidation treatment. By comparison of the results for various classes of antibiotics, we find that more chemically complex antibiotics require more radical oxidations. This suggests that the ●OH radicals are primarily oxidizing peripheral moieties in the more complex antibiotic molecules, instead, for example, breaking the 4-membered ring moiety in the main structure of the β-lactams.

Removal of β-lactam antibiotics from waters using advanced oxidation processes

251st National Meeting (2016)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.