Elemental signatures for microbial forensics

Elemental signatures in microorganisms are influenced by the organism's growth environment, postharvest modifications, and environmental exchange. It is clear that for organisms of the genus Bacillus, signatures from growth medium have the potential to remain robust for a long enough period of time to be useful from the standpoint of forensic investigation. Analogous to the compositional analysis of bullet lead (CABL), elemental signatures that are statistically indistinguishable between samples do not necessarily imply the samples have identical histories. Thus, the usefulness of elemental analyses lies in developing investigative leads and exonerating suspects rather than linking absolutely a suspect with a sample. More research is required in order to understand the ubiquity of useful signatures among types of organisms, the stability of individual signatures and the potential for overprinting by environmental influences.