ADSORPTION OF NATIVE WASTEWATER VIRUSES BY IRON OXIDE-COATED SAND

Waterborne pathogenic viruses pose a significant risk to public health. Although modern wastewater treatment facilities employ potent methods to remove microorganisms, disinfection is not 100% effective, and some microbes persist. Further, resource-limited regions lack adequate infrastructure to support tertiary processes and conventional wastewater treatment altogether. Mounting interest in nanotechnology has spurred investigation into new antimicrobial agents, and current environmental studies recommend iron oxide nanoparticles (IONPs) for their sorbent and catalytic capabilities. Literature suggests that IONPs could play a substantial role in wastewater reclamation by electrostatic adsorption and degradation of recalcitrant contaminants of emerging concern. Because both viral protein capsids and IONPs have ionizable functional groups, their surface charges are variable depending on solution potential of hydrogen (pH) and ionic strength. Batch microcosm experiments were conducted to determine the optimal reaction conditions for viral adsorption and inactivation by iron oxide-coated sand. Virus-like particle (VLP) abundance and community composition were measured pre- and post-equilibration using epifluorescence microscopy (EFM) and genetic fingerprinting (RAPD-PCR) to learn the extent of adsorption and changes in viral composition following reaction with uncoated and iron oxide-coated sand (IOCS). The greatest reduction in virus count and alteration in community composition occurred in IOCS treatment groups. IOCS significantly decreased the number of VLPs post-equilibration, on average, by 92.63%.