At the conclusion of this chapter, students will be able to:
Humans have used tobacco products for thousands of years. Tobacco cultivation likely began with the development of agriculture in Central Mexico thousands of years ago. It was originally used by Native Americans in religious ceremonies and for medical purposes. Early in tobacco’s history, it was used as a cure-all remedy, for dressing wounds, reducing pain, and even for tooth aches. In the late 15th century, Christopher Columbus was given tobacco as a gift from the Native Americans. The arrival of Spain introduced tobacco to Europe which gained rapid popularity, for it became a lucrative, heavily traded commodity to support the popular habit of smoking. By the early 17th century, scientists were discovering the consequences that smoking tobacco had on people’s lives, including difficulty with breathing and trouble with quitting.
It wasn’t until the 1900’s that cigarettes were made and sold as a major tobacco product in the U.S. Before this, tobacco was used primarily in pipes and cigars, by chewing, and in snuff. In 1901, 3.5 billion cigarettes were sold in the U.S. and more and more tobacco companies were established, creating an entire industry that gained a lot of power. In 1964, the Surgeon General’s report on smoking tobacco was released, shining light on the serious health effects cigarettes were causing. This report also allowed the government to initiate the regulation of the production and sales of cigarettes. In 1985, less than a century after cigarettes became popular, lung cancer became the number one cause of death in women. Rates for lung cancer were even higher than breast cancer at this time. In 1988, Congress prohibited smoking on domestic commercial airline flights scheduled for 2 hours or less. By 1990, the ban was extended to all commercial U.S. flights. On March 21, 2000, the U.S. Supreme Court ruled that the FDA lacks jurisdiction under the Federal Food, Drug, and Cosmetic Act to regulate tobacco products. As a result, the FDA’s proposed rule to reduce access and appeal of tobacco products for young people could not materialize. 1-3
The most common tobacco products, cigarettes are made from leaves of Nicotiana tabacum, which is cured and usually smoked . Nicotine is an alkaloid compound substance and has several natural sources, including tobacco plants, tomatoes, potatoes, eggplant and green peppers. Nicotine as a highly addictive substance has only one natural source—tobacco plant.
There are approximately 50 million people in America who are addicted to some type of tobacco product. Major commercial tobacco products include cigarettes, cigars, snuff, chewing tobacco, and pipe tobacco. Research has shown that nicotine may not be the only ingredient in tobacco that affects its addictive potential. Smoking is linked with a marked decrease in the levels of monoamine oxidase (MAO), an important enzyme that is responsible for the breakdown of dopamine, as well as a reduction in MAO binding sites in the brain. This change is likely caused by some other chemical compound in tobacco smoke other than nicotine. Animal research indicates that acetaldehyde, another chemical in tobacco smoke created by the burning of sugars added as sweeteners, dramatically increases the reinforcing properties of nicotine and may also contribute to tobacco addiction.
Electronic cigarettes—or e-cigarettes—are also called vapes, e-hookahs, vape pens, tank systems, mods, and electronic nicotine delivery systems (ENDS). Using an e-cigarette is commonly called vaping. E-cigarettes work by heating a liquid to produce an aerosol that users inhale into their lungs. The liquid can contain nicotine, tetrahydrocannabinol (THC) and cannabinoid (CBD) oils, and other substances, flavorings, and additives. THC is the psychoactive mind-altering compound of marijuana that produces the “high.”
E-cigarettes have the potential to benefit adult smokers who are not pregnant if used as a complete substitute for regular cigarettes and other smoked tobacco products. E-cigarettes are not safe for youth, young adults, pregnant women, as well as adults who do not currently use tobacco products. While e-cigarettes have the potential to benefit some people and harm others, scientists still have a lot to learn about whether e-cigarettes are effective in helping adults quit smoking. E-cigarette, or vaping, products (nicotine- or THC-containing) should never be used by youths, young adults, or women who are pregnant. Recently an outbreak of Lung Injury Associated with the Use of E-Cigarette, or Vaping, Products, has been reported. CDC, the U.S. Food and Drug Administration (FDA), state and local health departments, and other clinical and public health partners are investigating a national outbreak of e-cigarette, or vaping, product use-associated lung injury (EVALI). As of February 18, 2020, a total of 2,807 hospitalized e-cigarette, or vaping, product use-associated lung injury (EVALI) cases or deaths have been reported to CDC from 50 states, the District of Columbia, and two U.S. territories (Puerto Rico and U.S. Virgin Islands). Persons who never smoked or used other tobacco products or e-cigarettes are strongly advised not to start using any tobacco product.4-6
Nicotine is readily absorbed from all over the body, including lungs (smoked); mucosa (cigar, chewing tobacco, gum, nasal spray); skin (patch); and gastrointestinal tract (uncommon).
A chemical in cigarette smoke seems to slow the breakdown of dopamine by affecting MAO levels. Nicotine is a direct agonist for nicotinic ACh receptors. Nicotine initially causes a rapid release of adrenaline, the "fight-or-flight" hormone. Nicotinic ACh receptors are found in the limbic system (e.g. striatum, hippocampus, accumbens), midbrain (e.g. VTA, substantia nigra), various cortical areas (frontal lobe). Nicotine also increases release of various neurohormones and has powerful effects on peripheral nervous system, heart, and other organs.
Addiction to Tobacco Products
Dependence is a maladaptive pattern of substance use, leading to clinically significant impairment or distress, as manifested by three (or more) of the following, occurring at any time in the same 12-month period:
People addicted to tobacco products have a physical desire to continue using tobacco, but they also have a psychological desire because of memories associated with using. These memories trigger the urge to use tobacco. Triggers can be anything from music to certain people or places. There is also a strong behavioral addiction associated with nicotine addiction. Most people with an addiction to nicotine are aware of the harm tobacco causes, yet they continue to use the substance. This abusive behavior is characteristic of addiction. No matter how long a person has been addicted to tobacco, quitting is absolutely possible and has tangible health and financial benefits.5-8