Clearing the air on ancient smoke

Four thousand years before Hunter S. Thompson took his psychedelic trip through Las Vegas, ancient Americans were smoking mind-altering plants of their own.

Pipes and drinking vessels uncovered at archeological sites across the United States and Canada reveal ceremonial smoking and consumption of psychoactive and hallucinogenic plants was widespread in North America as far back as 2000 B.C.E.

The types of plants North America’s original inhabitants smoked, ate, or drank varied by time and region. To date, it is extremely difficult for researchers to deduce whether resin in a pipe excavated in the Pacific Northwest, for example, was from tobacco or one of the nearly 100 other plants Native Americans are known to have used.

Shannon Tushingham, assistant director of the Museum of Anthropology, plans to change that. She is working with David Gang, associate professor in the Institute of Biological Chemistry, and a multi-disciplinary team of researchers to develop a new way of analyzing the residue from archaeological artifacts. The research will help scientists understand the spread and use of ritual and medicinal psychoactive plants across North America and elsewhere around the world.

“Native Americans in the Northwestern United States and Canada were smoking 3,000 years ago,” Tushingham said. “Were they smoking tobacco that far back in time, and, if so, did they trade for it or grow it themselves? Our research will help scientists answer difficult questions like this.”

Molecular fingerprints

Tushingham and Gang are currently developing a list of chemical fingerprints that correspond to the resin from different types of plants Native Americans smoked. The difficulty with this is a plant’s biochemical signature changes when it is cooked, smoked, or buried underground for long periods of time.

“This means that in order to develop identifying markers that link resin from an excavated pipe to a particular plant we need to burn the plants ourselves,” Gang said. “We will then use something called liquid chromatography-mass spectrometry (LC/MS) to figure out the molecular markers that are specific to the burnt plant resin in question.”

Tushingham’s current project builds from her previous research at the University of California, Davis. Using a process called gas chromatography-mass spectrometry (GC/MS), her fellow researchers identified trace amounts of tobacco in a 1,150-year-old pipe that Tushingham discovered in an excavated plank house in northwestern California. The discovery was by far the earliest example of tobacco smoking in the Pacific Northwest.

The chemical analysis techniques Tushingham and Gang hope to develop will provide scientists with a more efficient and accurate method to identify psychoactive plant use in the past.

“Our hope is this project will help to develop a better understanding of how the biochemical signature of a particular plant changes through the cooking and or smoking process,” Gang said.

Practice makes perfect

In a greenhouse across from the WSU Alumni Centre, Gang and molecular plant sciences PhD candidate Korey Brownstein are growing Datura, Artemisia, different strains of tobacco, and other plants native to the Americas.

“Basically we will take a leaf sample, freeze dry it, grind it up, and then burn it or cook it in a ceramic replica,” Brownstein said. “We will then shoot the resin we get through our Liquid chromatography–mass spectrometry machine to get a fingerprint that corresponds to a certain type of plant. It is kind of like CSI of ancient artifacts.”

In the basement of the Fine Arts Building a few blocks away from the greenhouse, ceramic technician and fine arts instructor David Herbold is firing ceramic pipes and drinking vessels. His replicas will soon be put to work smoking and simmering the dried plants for the project.

“As an artist it is a special opportunity to be working with researchers on the ground level rather than illustrating their work after the fact,” he said. “People are always talking about scientists reaching out and being involved in the humanities, but, likewise, adding artistic sensitivity to the scientific process is a really cool thing.”

Tushingham and a team of undergraduate researchers plan to start “smoking” Herbold’s replicas early next month. To simulate the process of smoking, the researchers tape a syringe to a ceramic pipe’s mouthpiece, and then pull the plunger to simulate someone taking a long draw. Afterwards, the pipe is cut up into different pieces and analysis is done on the residue. The researchers will then use LC/MS to identify chemical markers left by the burnt resin.

They will use these markers to match resin from ancient pipes Tushingham and colleagues uncovered in northwestern California, British Columbia, and other North American locations.

“Our research will really help to elucidate a history of ceremonial and medicinal plant use by Native Americans that stretches back many thousands of years,” Tushingham said. “We honestly don’t know what many different groups of Native Americans were smoking or where they got it from. We might even find something completely new.”