A group of scientists, including Washington State University researchers, demonstrated for the first time that nicotine residues can be extracted from plaque (also known as “dental calculus”) on ancient tobacco users’ teeth.
Their research provides a new method of determining who consumes tobacco in the ancient world and can help trace tobacco and other exciting plants back further into prehistory.
“The ability to identify nicotine and other botanicals in ancient plaque can help us answer long-term questions about ancient human consumption of drugs,” said assistant professor of Anthropology at WSU, Shannon Tushingham, co-author of a new study. Research on “Journal of Archaeology”.
“For example, it can help us determine whether all members of society use tobacco, or only adults, or only men or women.”
A new source of information
Tracing the ancient tobacco circulation in the Americas has traditionally relied on pipelines, burnt tobacco seeds, and analysis of hair and fecal material. However, these items are rare in archaeological records and it is difficult to contact specific individuals. Therefore, it is difficult to use tobacco for archaeological records.
On the other hand, as time goes by, plaque adheres to the tooth surface and mineralizes, preserving various substances in the oral cavity. It is easy to link to specific individuals because it can be removed directly from the teeth.
Despite this, until recently, archaeologists still mostly ignored plaque.
However, scientists use modern and highly sensitive instruments and found that they can detect and characterize trace amounts of various compounds, including proteins, bacterial DNA, starch grains, and other plant fibers in dental plaque.
Because nicotine can be detected in the plaque of contemporary smokers, Tushingham and her collaborators want to know if it is also preserved in the plaques of people who lived long ago.
She and Professor David Gang of the WSU Institute of Biochemistry, Korey Brownstein, a graduate student of the WSU Molecular Plant Science Program, and an anthropologist Jelmer Eerkens of the University of California, Davis, collaborated with members of the Ohlone tribe to extract from the teeth of 8 people in the San Francisco Bay. Plaques were buried 6,000 to 300 years ago and analyzed for nicotine.
Eerkens and his team at the University of California, Davis used ordinary dental files to extract dental plaque from ancient teeth and then sent it to laboratories in Tushingham and Gang, Washington. Researchers at the University of Washington used liquid chromatography-mass spectrometry to detect nicotine and other botanicals in samples such as caffeine and atropine, a muscle relaxant.
Two of the samples they analyzed were positive for nicotine, and for the first time demonstrated that the amount of drug that can survive in ancient plaques can be detected. One of them, an adult man, was also buried in a pipe. An old woman’s cavities had a surprise, and the woman also had a positive reaction to nicotine.
Eerkens said: “While we can’t draw any broad conclusions about this case, her age, gender, and use of smoking are very interesting.
“She may have passed child-bearing age, probably a grandmother. This supports recent research showing that young adult women in traditional societies avoid plant toxins such as nicotine to protect infants from harmful biochemicals, but older women can Need or need to consume these anesthetics. ”
Although the researchers did not find evidence of any other botanical drugs in this particular study, they believe that plaque can be used to help track the use and spread of other toxicants.
Brunstin said: “We think that a variety of plant-based, intoxicating chemicals can be detected in ancient plaque. “It does open up many interesting discoveries. ”