Transport of Human Adenoviruses in Water Saturated Laboratory Columns

Abstract

Groundwater may be contaminated with infective human enteric viruses from various wastewater discharges, sanitary landfills, septic tanks, agricultural practices, and artificial groundwater recharge. Coliphages have been widely used as surrogates of enteric viruses, because they share many fundamental properties and features. Although a large number of studies focusing on various factors (i.e. pore water solution chemistry, fluid velocity, moisture content, temperature, and grain size) that affect biocolloid (bacteria, viruses) transport have been published over the past two decades, little attention has been given toward human adenoviruses (hAdVs). The main objective of this study was to evaluate the effect of pore water velocity on hAdV transport in water saturated laboratory-scale columns packed with glass beads. The effects of pore water velocity on virus transport and retention in porous media was examined at three pore water velocities (0.39, 0.75, and 1.22 cm/min). The results indicated that all estimated average mass recovery values for hAdV were lower than those of coliphages, which were previously reported in the literature by others for experiments conducted under similar experimental conditions. However, no obvious relationship between hAdV mass recovery and water velocity could be established from the experimental results. The collision efficiencies were quantified using the classical colloid filtration theory. Average collision efficiency, α, values decreased with decreasing flow rate, Q, and pore water velocity, U, but no significant effect of U on α was observed. Furthermore, the surface properties of viruses and glass beads were used to construct classical DLVO potential energy profiles. The results revealed that the experimental conditions of this study were unfavorable to deposition and that no aggregation between virus particles is expected to occur. A thorough understanding of the key processes governing virus transport is pivotal for public health protection.

Cotransport of human adenoviruses with clay colloids and TiO2 nanoparticles in saturated porous media: Effect of flow velocity

“…To our knowledge, to date, there has been no study on human adenovirus transport in saturated porous media in the presence of clay colloids and TiO 2 NPs. Certainly, this work is a substantial extension of the work conducted by Kokkinos et al (2015), who studied the effect of flow velocity on the transport of human adenoviruses. Column experiments were conducted using glass beads as the column packing material in order to eliminate possible experimental difficulties associated with real soil, which may provide numerous uncertainties that can considerably complicate the analysis of the experimental data.…”

“…Fig. 2 shows the normalized breakthrough data for the cotransport of hAdV35 with KGa-1b, STx-1b and TiO 2 NPs, at three flow rates (2.5, 1.5, 0.8 mL/min), together with the breakthrough data for the transport of hAdV35, which were collected by Kokkinos et al (2015). Note that the total virus concentrations represent the sum of suspended viruses and viruses sorbed onto suspended particles (C Total-v = C v + C vp ).…”

“…Consequently, numerous experimental and theoretical studies published in the literature have investigated how virus fate and transport can be affected by various physicochemical factors (Jin et al, 2000;Walshe et al, 2010;Sadeghi et al, 2011). Also, our group has previously investigated how virus transport can be influenced by environmental parameters such as fluid velocity (Syngouna and Chrysikopoulos, 2011;Kokkinos et al, 2015), matrix structure (Masciopinto et al, 2008), moisture content (Sim and Chrysikopoulos, 2000;Anders and Chrysikopoulos, 2009), grain size (Anders and Chrysikopoulos, 2005;Syngouna and Chrysikopoulos, 2011), gravity (Chrysikopoulos and Syngouna, 2014), and presence of suspended clays (Syngouna and Chrysikopoulos, 2013Katzourakis and Chrysikopoulos, 2014). It should be noted, however, that most of these studies use bacteriophages as surrogates for human viruses.…”

“…Many studies have investigated the influence of just a single environmental variable on human adenovirus inactivation and attachment onto porous media (e.g. flow velocity, temperature, clay presence) (Wong et al, 2012;Pang et al, 2014;Kokkinos et al, 2015;Bellou et al, 2015). To our knowledge, to date, there has been no study on human adenovirus transport in saturated porous media in the presence of clay colloids and TiO 2 NPs.…”

Applying Quantitative Molecular Tools for Virus Transport Studies: Opportunities and Challenges

“…Three recent studies by independent research groups (Shi et al 2012;Pang et al 2014;Wong et al 2014), applied qPCR to column filtration experiments and they all found mobility of human adenovirus (HAdV, the most prevalent enteric virus in water environments) (Wong et al 2012a) to be much lower than MS2 (the most frequently used bacteriophage in virus transport studies) (Jin and Flury 2002;Wong et al 2014) in sand media. Another study also found mass recovery of HAdV from glass beads column effluents lower than coliphage reported in previous studies (Kokkinos et al 2015). One study, however, reported higher retention of MS2 than HAdV in fine granular limestone aquifer material; and suggested that PRD1 was a better transport indicator than MS2 for HAdV in this type of media (Stevenson et al 2015).…”