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Evidence Of Early Tobacco In Northeastern North America

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Rafferty, Sean (2006). Evidence of Early Tobacco in Northeastern North America? Journal of Archaeological Science 33:453-458

This article examines the origins of early usage of tobacco and nicotine products in Eastern North America dating back as early as 300B.C. Nicotine functions by binding to nicotinic acetylcholine receptors, causing increased heart rate, vasoconstriction, and increased alertness. In sufficient doses nicotine can have hallucinogenic effectsÐ'..." (Rafferty, 5). One method of researching this was through gas chromatography/mass spectroscopy (GC/MS) to find nicotine residue compounds in old tobacco pipes. The Boucher site, located in Vermont, had been studied in an effort to find pipes that contain residue from tobacco and from there, determine a date in which it was used. The pipes themselves are not available to be researched, but the residue that was once inside of them is.

Once the residue has been obtained, the nicotine is separated from the substance through a very careful process. "This is done by refluxing an organic solvent, methylene chloride, through a soxhlet extractor which percolates the solvent through the sample" (Rafferty, 2). This process, in a way, sifts out the nicotine from the unnecessary residue leaving you with product to be further researched. The solvent is then evaporated under nitrogen, and the remains are inserted into the gas chromatography/mass spectroscopy (GC/MS), where the sample begins to undergo increasing temperatures ranging from sixty degrees to one hundred and fifty degrees, all while increasing at a rate of thirty degrees per minute. Nicotine is expected to have a retention time of 12.9 minutes. In this process, different particles separate, making it easier for researchers to observe the nicotine. A "mass selective detector" breaks up the particles into fragments, in order of increasing weight.

One flaw with this method is that the nicotine residue changes over time and may be improperly detected as something else and possibly overlooked. The article states that there has been evidence of nicotine decaying into other compounds over time. This means that real nicotine may decay and be mistaken for something else, and be disregarded when in fact; it is real and would be an excellent candidate for research. Conversely, other compounds may decay and begin to show the same traits as nicotine would upon detection and get sent off for research as nicotine when it is not, causing invalid results. As a solution to this potential problem, "a primary goal of future research will be the identification of the specific compounds that are indicative of nicotine in pipe samples" (Rafferty, 4). Knowing exactly which compounds can be mistaken for nicotine as well as which compounds nicotine can be mistaken for will help avoid this problem and make it possible to maintain reliable data at the same time.

Also, the scan mode that the researcher decides to use makes a difference in the validity and reliability of the results. There are two major types of scan modes. The "scan" mode examines the substance and lists off each and every compound that is present in the sample. This scanning method is less sensitive than the other type of scan, being the "select ion monitoring" or "SIM" scan. This scan is better at picking up compounds that the "scan" may have missed

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