Sweat as an Alternative Biological Matrix

Abstract

Situations with medico-legal implications, such as crime under the influence of alcohol/drugs, need the support of forensic toxicology. In order to identify drug use/abuse, toxicologists analyze biological specimens collected from corpses or living people. In the last decades, various specimens other than traditional blood and urine have been studied by researchers in order to support data obtained with conventional samples. Sweat is considered a suitable matrix with a peculiar time window of detection up to one week after intake; it can be collected by the means of patches that trap the xenobiotics released by sweat. Parent drugs are generally excreted at higher levels than metabolites, and the concentrations are expressed as nanograms/patch. It offers a non-invasive alternative for the monitoring of drugs exposure in living people as it can be collected for a programmed period with minimal disturbance for the individual. The main disadvantages of working with sweat are related to the amount of sample collected, which is variable and very low. The analysis of sweat may find applications in the monitoring of drug abuse as the patches provide a long-term detection of drug exposure. Forensic toxicology can benefit from sweat testing, for example in workplace drug testing or doping control.