A Non-Contact Passive Approach for the Effective Collection of Target Explosive Volatiles for Canine Training Aid Development

Abstract

The use of real explosive materials for canine training involves inherent dangers, toxicity risks exposure, and often limited availability of the training material all of which may affect the reliable training of canine teams. For this reason, the development of a training aid suitable for daily operations is beneficial to provide safe and effective explosive detection training that can provide for enhanced detection capabilities. This study presents a non-contact passive approach for the collection of target volatile organic compounds (VOCs) emanating from real explosive materials to be used as potential canine training aids. This will also provide the ability for the creation of new training aids based on the rapid evolution of new explosive threats. Experiments were performed based on previously identified explosive signature volatiles such as 2-ethyl-1-hexanol (2E1H), 2,3-dimethyl-dinitrobutane (DMNB), and 2,4-dinitrotoluene (2,4-DNT). Composition 4 (C4) explosive material was used for the static collection of the 2E1H and DMNB, as well as single based smokeless powder for the collection of 2,4-DNT. The samples were collected in a controlled environment and cotton gauze pads were used as the collection material. A time optimization analysis was conducted for all three target volatiles in time intervals of ranging from 0.5 to 120 minutes. Solid phase microextraction (SPME) was used along with gas chromatography-mass spectrometry/electron capture detection (GC-MS/ECD) for extraction and confirmation of target volatiles. The results show that collection of characteristic volatiles are obtained after 15 min of exposing the gauze pad to 2E1H and 30 min was optimal for DMNB and 2-4, DNT. Overall, the results demonstrated the possibility to perform static collection of signature VOCs from real explosive materials onto a gauze pad via a non-contact passive method for its potential use as effective canine training aid.