Sustainable collection and complete extraction of oral fluid for forensic toxicology applications

Among the several biological matrices, saliva (or oral fluid (OF)) has gained acceptance over the past decades as an alternative biological matrix, it became prevalent over blood and urine for illicit drug screening (driving under the influence of drugs investigations) and diagnostic applications (detection of biomarkers involved in cancer, heart and infectious diseases) and it is considered the best research tool for scientific investigations on humans from an ethical point of view [1]. OF provides a simple and non-invasive procedure with easy storage and transportation properties and also reduces risk of cross contamination and exposure of personnel. However, even if extremely simple, sample collection is a critical part in the analytical workflow as well as a waste generator stage. Collection methods involve spitting, passive drool or disposable devices with some type of absorbent material (e.g., foam pad) [2,3]. Commercial devices that are typically used are in plastic material so they should give incomplete desorption of lipophilic drugs or metabolites and similarly to other diagnostics wastes they are generally destroyed through open burning and incineration, resulting in the emission of dioxins, furans and particulate matter. Measures to ensure the safe and environmentally sound management of these wastes are of particular interest for a sustainable development.