Nicotine is a naturally occurring, alkaloid substance which is found in the leaves of some plants; most notably the tobacco plant. It is a relatively simple heterocyclic molecule incorporating two ring structures in which the hetero atom is nitrogen. The compound is produced in the roots of the plants, but is accumulated in the leaves where its function is to dissuade herbivores and insects from eating the plant. This characteristic led to the use of nicotine as an insecticide in the past and some modern insecticides still use nicotine derivatives. In the tobacco plant, nicotine can constitute 0.6 to 3.0% of the dry weight of the leaf, depending on the variety of plant and the growing conditions.
Nicotine is a toxic compound and 0.5 to 1mg/kg body weight of the pure substance is enough to be fatal to a human. The compound is regarded as being highly addictive and is credited as being the agent that causes smokers to become addicted to their habit. Nicotine in tobacco smoke is not present at a high enough concentration to be fatal and it does not cause cancer (other compounds and soot particles in tobacco smoke are responsible for this). According to the National Institute on Drug Abuse, 90% of lung cancers in the USA are attributable to smoking and each year some 38,000 people die from illnesses related to secondary smoking. In most American states, smoking is reserved to adults aged 18 years and over, but a survey in 2008 found that 71 million Americans (roughly a third of the population) aged 12 and over had smoked at least once in the month leading up to the survey.
Some health insurance companies will take a blood sample during a medical examination to determine if they will offer cover and to set the premium. Will nicotine show up in a blood test? The answer is most certainly yes – provided the laboratory conducting the analysis performs the specific tests required. Nicotine is usually detected by gas chromatography on a blood sample. The retention time on the chromatograph can be used to identify the compound and the signal generated is proportional to the blood borne concentration of the drug. Numerous other methods have been developed for measuring nicotine or its metabolic derivative cotinine in blood samples including HPLC-MS-MS and immunologically based tests.
The biological half-life of the nicotine is about two hours and it takes somewhere in the region of seven seconds for it to cross the blood-brain barrier upon taking cigarette smoke into the lung. If you are addicted to nicotine and desperate for cheaper health insurance, a better question would be how long will nicotine show up in a blood test? The clearance rate for nicotine from blood is between two to four days. So, if you can refrain from smoking for a week prior to the test, it is unlikely that a medical screening test would be sensitive enough to detect that you were a smoker. Since smoking is arguable the single greatest cause of premature death in the Western world, the best advice you can be given as a nicotine addict is simply to stop smoking - perhaps easier said than done!
- National Institute On Drug Abuse: http://www.drugabuse.gov/drugpages/nicotine.html
- British Lung Foundation: http://www.lunguk.org/