Dental calculus as a source of ancient alkaloids: Detection of nicotine by LC-MS in calculus samples from the Americas

Abstract

A B S T R A C TDental calculus has been shown to be a repository of a variety of exogenous organic materials, including bacterial DNA, proteins, phytoliths, and starch grains. Here we show that certain alkaloids, nicotine in this case, can also be trapped and preserved in ancient dental calculus. We present Ultra-Performance Liquid ChromatographyMass Spectrometry (UPLC-MS) results of analyses of ten archaeological calculus samples from eight individuals from Central California. Two samples tested positive for the presence of nicotine, including one from an individual buried with a pipe. UPLC-MS analyses of dental calculus could provide an alternative means to trace the spread and consumption of tobacco and other plants with distinctive alkaloid products in ancient societies. As shown here for the first time in ancient samples, the ability to detect nicotine alkaloids in calculus has enormous potential to help us better understand the consumption of intoxicant plants by ancient humans on the individual level, for example by giving us the ability to test assumptions about the age, sex, and status of individual tobacco users in the past.

Biomolecular archaeology reveals ancient origins of indigenous tobacco smoking in North American Plateau

“…Chemical identification techniques using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) allow archaeologists to identify tobacco use through the identification of the biomarker nicotine found in residues extracted from ancient pipes, human hair, ceramics, and dental calculus ( 10 – 12 , 34 – 38 ). At present, the earliest bimolecular evidence of tobacco use/ancient smoking practices is in areas where tobacco was farmed, in eastern North America and South America; much less is known about hunter-gatherers’ tobacco use, especially in northwestern North America ( 13 ).…”

Microscopic Analysis of Starch Grains and its Applications in the Archaeology of the Stone Age

“…This material also contains other components such as organic materials or chemical components. It is a rich source of the tracks left by an ancient life style (Leclerc et al, 2018, Copeland, Hardy, 2018Eerkens et al, 2018). Calculus must be carefully pulled down onto metal foil.…”

A multidisciplinary approach for investigating dietary and medicinal habits of the Medieval population of Santa Severa (7th-15th centuries, Rome, Italy)

“…pollen grains), accidentally or intentionally inhalated/ingested during everyday activities (providing information on the surrounding environment) [27,36]. Dental calculus tends to be well preserved in archaeological contexts [34] and is increasingly recognised as a valuable resource to investigate past human diet and phytotherapeutic practices [22,[37][38][39][40][41][42][43]. The analysis of dental calculus was mainly performed by light microscopy (henceforth LM); only rarely gas-chromatography-mass spectrometry (henceforth GC-MS) and occasionally genetic techniques have been combined [20,22].…”