Impact of Environmental Conditions on the Enzymatic Decontamination of a Material Surface Contaminated with Chemical Warfare Agent Simulants

The efficacies of enzyme-based technologies developed for the decontamination of surfaces contaminated with chemical warfare agent simulants were measured as a function of operating and environmental conditions mimicking possible outdoor conditions. Bench-scale decontamination testing was used to evaluate two enzyme-containing products for their ability to neutralize paraoxon and 2-chloroethyl phenyl sulfide (2-CEPS) selected as simulants of G-, V-series chemical agents and sulfur mustard, respectively. Residual amounts of the simulant on galvanized metal coupons were measured following application of the enzyme. Both enzymatic decontamination methods performed fairly well against the simulants, with higher efficacies at higher temperature against paraoxon and the opposite trend for the second enzyme solution against 2-CEPS. A longer interaction period resulted in better efficacy. Reapplication of fresh enzyme solution yielded a major improvement in efficacy. The neutral pH of both enzyme solutions makes this decontamination approach a useful decontamination tool for surfaces on which harsher decontamination products cannot be applied.