AWWA WSC61386

Drinking water distribution systems supplying large population centers must be considered asserious potential targets for terrorists. Contamination of distribution system equipment would resultfrom adherence of contaminants to biofilms, tubercles and other corrosion products lining the pipes, orfrom permeation of the pipe material itself. Because of their non-toxic, non-corrosive, and environmentallybenign properties, enzymes may provide an ideal method for the treatment of agents, pesticides orother chemical contaminants in drinking water systems, as well as the decontamination of pipes andother equipment with contaminant residue. Additionally, enzymes have been demonstrated to functionin foams, sprays, lotions, detergents, and other vehicles that can be used in flowing water or on materialsurfaces. The goal of this project was to identify, develop, and evaluate at least one enzyme-based methodfor treating flowing contaminated water, and one enzyme-based method for decontaminating drinkingwater pipes. A literature search was conducted to identify the potential of enzymes to treatcontaminated drinking water and/or to decontaminate distribution systems equipment. The literaturesearch considered the potential application of enzymes to a large range of possible water contaminationscenarios, from groundwater to drinking water, from toxic industrial chemicals (TIC's) to chemicalwarfare agents. Enzyme-based decontaminants have been under development for many years at the U.S. ArmyEdgewood Chemical Biological Center (ECBC) for military use. Enzymes with catalytic activity againstnerve agents, related organophosphorus pesticides, sulfur mustard and biological agents have beenidentified and are in various stages of development. In order to evaluate the potential for enzymes todeal with contaminated water supplies or water distribution systems, two approaches are being taken.The first is a liquid formulation that will consist of soluble stabilized enzymes. The second is a filtersystem with immobilized enzymes through which contaminated water is passed. Two well characterizedenzymes are being used in these studies: Organophosphorus Acid Anhydrolase (OPAA),a bacterial enzyme with the highest known activity against G-type nerve agents (ex. Sarin); and OrganophosphorusHydrolase (OPH), an unrelated bacterial enzyme with excellent activity against organophosphoruspesticides as well as lesser activity against G- and V-type nerve agents. Preliminaryresults on the stabilization and immobilization of these enzymes is presented. Although also applicableto biological contaminants, this paper only deals with the chemical varieties. Includes 99 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

04/10/2005

Number of Pages:

20

File Size:

1 file