Reversible Inactivation of Viruses in Groundwater

EPA Grant Number: R824875
Title: Reversible Inactivation of Viruses in Groundwater
Investigators: Alvarez, Maria E. , Pillai, Surresh
Institution: El Paso Community College , Texas A&M Agricultural Research and Extension Center
EPA Project Officer: Hiscock, Michael
Project Period: September 15, 1996 through September 14, 1998
Project Amount: $176,939
RFA: Exploratory Research - Minority Institutions (1995) Recipients Lists
Research Category: Water , Land and Waste Management , Ecosystems , Air , Aquatic Ecosystems


Viral contamination of surface and groundwater is a potential problem along the U.S.-Mexico Border, which deserves to be studied in detail using a variety of approaches. Mexican border communities lacking sewage treatment plants discharge untreated sewage into the Rio Grande. Also, the existence of "colonias" lacking potable water and sewage facilities on both sides of the border contributes to the possibility of fecal contamination of groundwater. Since the U.S.-Mexico Border area share their water supplies, an accurate assessment of the extent of viral contamination from fecal origin is of paramount importance. Preliminary data indicates that viruses can exist in groundwater in a state that could be referred to as reversibly inactivated. The existence of such viral particles can lead to underestimation of viral numbers since changes in environmental conditions like temperature, pH, ionic composition, or chemical discharges form maquiladora plants from other sources could lead to viral reactivation. Although information exists on the inactivation kinetics of a variety of viruses in surface and groundwater, to understand the nature of viral reactivation is vital to determine the mechanisms of viral inactivation in water a the molecular level. The specific objectives of the proposed project will be: 1) to determine the mechanisms of inactivation of model viruses like MS2 coliphage and poliovirus type 1 in groundwater by correlating percent inactivation values with structural and compositional changes associated with the viral capsid and/or RNA; and 2) to determine whether the viral particles that have entered the reversibly-inactivated state could become infectious and to identify environmental factors such as temperature, pH and ionic composition that could promote or retard the process. Data on viral inactivation/reaction mechanisms and the environmental factors that affect these phenomena will help explain the contradictory results found in the literature on the efficiency of disinfection procedures on a variety of viruses like HIV and Hepatitis A, and will provide guidelines for the development of more effective methods for detection and enumeration of viral contaminants found in natural and treated water systems.

Supplemental Keywords:

Health, Scientific Discipline, Geographic Area, Waste, US Mexico Boarder, Environmental Chemistry, Chemistry, Epidemiology, State, Disease & Cumulative Effects, Biology, Groundwater remediation, health effects, risk assessment, maquiladora plants, reversable inactivation, infective dose, US Mexico Border, virus cultivation, Texas, viruses, coliphage, disinfection procedures, Hepatitis, environmental toxicant, HIV, poliovirus, "Minority Institutions", TX, groundwater, toxicokinetics

Progress and Final Reports:

  • 1997
  • Final