Effect of Soil Properties on Saturated and Unsaturated Virus Transport through Columns

Abstract

Viruses from contaminant sources can be transported through porous media to drinking water wells. The objective of this study was to investigate inactivation and sorption of viruses during saturated and unsaturated transport in different soils. Bacteriophages phiX174 and MS-2, and Br- tracer in a phosphate-buffered saline solution were introduced into saturated and unsaturated soil columns as a step function under constant flow rate and hydraulic conditions. Results showed that significantly greater virus removal occurred in the unsaturated columns than in the saturated columns in the two soils containing high metal oxides content. However, the increase in virus retention under unsaturated conditions was not significant in two other soils having high phosphorus and calcium contents and high pH, and in another soil with high organic matter content. The results imply that the extent of water content effect on inactivation and sorption of viruses can range from significant to minimal depending on the properties of the transport medium. We found that the presence of in situ metal oxides was a significant factor responsible for virus sorption and inactivation. Therefore, soils with high metal oxides content may have the potential to be used as hydrological barriers in preventing microbial contamination in the subsurface environments. We also found that the water content effect on virus removal and inactivation strongly depended on solid properties of the testing medium.

Relação da velocidade de escoamento da solução e do comprimento da coluna de solo com os parâmetros de transporte de potássio em um latossolo e um neossolo

“…Vários estudos de deslocamento de substâncias químicas no solo, como agrotóxicos (Barizon et al, 2006;Montoya et al, 2006;Raymundo et al, 2009) e reguladores de crescimento vegetal (Milfont et al, 2008), são realizados utilizando colunas de lixiviação. O movimento de microrganismos no solo também tem sido estudado em ensaios com colunas (Chu et al, 2003;Guber et al, 2005;Rockhold et al, 2005).…”

Long-Term Persistence and Leaching ofEscherichia coliin Temperate Maritime Soils

“…The soil and subsoil type is believed to be a major factor influencing the potential transfer of pathogens through soil to groundwater (3,34,41,50). The preapplication moisture status of a soil, which may be influenced by the season, also impacts pathogen survival, fate, and transport (2,11,43,54).…”

Transport of Pathogen Surrogates in Soil Treatment Units: Numerical Modeling

“…That is, with decreasing water content, higher retention of bacteria and viruses in the soil has been observed [24,38,50,51]. Because the air-water interface increases at decreasing water content, the removal and retention of microbes in fine-grained soil, such as the clay loam, should be, at a given water content, greater than in granular soils [24,38,52]. In our study, the water content of the sand and sandy loam soils at the end of the experiment was lower (0.15 and 0.23 g/g, respectively), compared to the clay loam soil (0.32 g/g; Table 2).…”