Police crime scene examiners routinely use commercial alternative light sources (ALS) or forensic light sources (FLS) illumination systems comprising specific wavelength band torches and accompanying filtering goggles as a means of surveying crime scenes to locate and identify evidence such as biological materials. Extending the utility of such systems to contemporary toxic chemical hazards such as fentanyl derivatives could have significant safety benefits for operators but requires information on the fluorescence behaviour of different fentanyl derivatives and common cutting agents, as well as background and mixture effects.
We have collected solid and solution state fluorescence spectra of fentanyl hydrochloride and related analogues acryl fentanyl hydrochloride, remifentanil hydrochloride, and carfentanil hydrochloride, as well as other illicit drugs of concern to Australian policing agencies. The solid-state fentanyl emission profile was found to be broad and span the UV-Visible range, consistent with solution state spectra. This data informs the potential utility of ALS for fentanyl visualisation and allows parameters such as limits of visualisation to be estimated.
Finally, to inform how these emissive properties can be exploited by operators in practical applications, two ALS were used to examine fentanyl contamination in a range of crime scene and illicit drug lab scenarios. Under suitable conditions it was found that sub-milligram amounts of the hydrochloride salts of fentanyl analogues could be visualised, which points to opportunities for the mapping of gross fentanyl contamination by ALS systems.