Proof of concept novel low toxicity obscurant (SERDP WP2405)

Abstract

A significant health and possibly environmental problem is associated with military smokes and obscurants. Besides the fact that these obscuration munitions pose a significant toxicity hazard to the user, the environmental impact of these munitions can also be significant (e.g. due to the use of hexachlorethane). The objective of the SERDP project WP-2405, Proof of Concept Novel Low-toxicity Obscurant, is to investigate the technical feasibility to develop a new effective and environmentally benign obscurant. The project is a collaboration between TNO and Edgewood Chemical and Biological Center. As starting point the result of SERDP project WP-2148 [1] will be used, a sea salt based composition. The focus of the new project will be on the additional steps needed to gain a performance of approximately 70% (or better) of that of traditional HC smoke. The newly developed compositions vary in different additives, as to improve the overall performance of the obscurant while maintaining the low toxicity. Mass extinction coefficients were determined for different compositions by igniting 5 grams of pressed compositions in sub scaled grenades in a smokebox (V~2m3), at different relative humidity. The best five performing compositions were then studied to determine the acute toxicity for human lung cells in culture with an air-liquid interface system, VITROCELL®. This was done by igniting 10 grams in sub scaled grenades in a bio aerosol chamber (V~12m3)