Feces, fragrance and medicine chemical evidence of ancient therapeutics in a Roman unguentarium

Abstract

Fecal-based pharmacological treatments are widely attested in Greco-Roman medical texts, yet no direct chemical evidence has until now supported their practical application. This study presents the first molecular confirmation of such practices through GC–MS/FID analysis of organic residues from a Roman glass unguenta rium (artifact no. 4027) excavated in Pergamon, a major center of Roman medicine. The vessel’s contents revealed a distinctive blend of human fecal biomarkers (including coprostanol and 24-ethylcoprostanol) and aromatic compounds such as carvacrol, a major constituent of thyme oil. These results align with classical prescriptions that combined dung with odor-masking agents to enhance patient compliance − practices noted in the works of Galen, Dioscorides, and Pliny the Elder. By integrating archaeometric analysis with historical and philological research, the study reframes Roman unguentaria as vehicles not only for cosmetics, but also for socially managed therapeutic substances. The findings contribute critical empirical support for the pharmacological use of excrement in antiquity and offer a replicable interdisciplinary model for investigating ancient medicine. In light of contemporary interest in microbiome based therapies, this evidence also prompts a reconsideration of early traditions once dismissed as marginal or irrational.