Bioterrorism: the effects of biological decontamination on the recovery of electronic evidence

The investigation of a bioterrorism event will ultimately lead to the collection of vital data from electronic devices such as computers and mobile phones. This project sought to determine the use of gamma irradiation and formaldehyde gas as effective biological decontaminants, and the effect of these methods on the recovery of electronic evidence. Electronic items were contaminated with viable spores and then exposed to both decontaminants. Log values for each matrix were calculated with flash drives recording the highest value of 566 Gy for gamma irradiation and a maximum of 50 min exposure to formaldehyde saw the effective destruction of spores. The results indicate that recovery of data varied based on the decontaminant selected, formaldehyde gas giving the most promising results, with electronic data recovered after the required exposure time. Gamma irradiation proved damaging to electronic circuitry at levels required to render the items safe. The implications to computer intelligence and forensics will be discussed based on the outcomes of these findings.