PRELIMINARY STUDIES ON REMOVAL OF TETRACYCLINE AND CIPROFLOXACIN FROM SECONDARY WASTEWATER EFFLUENT BY VETIVER GRASS

The emergence of antimicrobial resistance due to long persisting antibiotic drugs in treated wastewater has emphasized the need for an innovative, economic, and eco-friendly remediation technique. In this study, we have investigated the potential of Vetiver (Chrysopogon zizanioides L.), a high biomass, fast growing perennial grass, to remove two widely used antibiotics, ciprofloxacin (CIP) and tetracycline (TTC) from secondary wastewater effluents. After consumption, majority of these antibiotics and their degradation products are excreted as active compounds, which eventually enters the environment through municipal sewage. Prolonged existence of these compounds in soil and water triggers the acquisition of antibiotic resistance to microorganisms. Significant (p<0.0001) photo degradation of these two antibiotics have been observed in clean water, but in wastewater, due to certain physical and chemical properties, optimal photo degradation does not happen; even UV irradiation fails to remove these pharmaceutical compounds. Being an accumulator of various organic and inorganic contaminants, the application of Vetiver System (VS) is very promising due to its high potential in removal of significant amounts of contaminants, and its cost-effectiveness. In our previous studies, we observed the potential of VS in removing CIP and TTC from hydroponic system. The main objective of this study is to evaluate the potential of VS in removing CIP and TTC from secondary wastewater effluents as a function of their initial concentrations (literature based median and maximum concentrations), and time of exposure. Vetiver grass was hydroponically grown in plastic jars, spiked with the respective antibiotic doses, and kept under greenhouse conditions. Samples were periodically collected to determine the kinetics of antibiotic removal, as well as removal of nutrients (nitrogen and phosphorus). Significant (p<0.0001) uptake (>70%) of TTC and CIP by VS from wastewater was observed within 15 days. The study is ongoing, and will continue for 60 days.