What is in a Cigarette

So what’s really in a cigarette? It’s good to find out, since much of what’s in a cigarette is also in the body of a smoker, and to a lesser extent, in those people inhaling second-hand smoke.

All tobacco products—cigarettes and cigars, as well as what goes in chew and pipes—start out from the dried leaves of herbs and shrubs from the genus Nicotiana, the species of which are typically referred to as tobacco plants. While many plants naturally contain the neurotoxin nicotine, plants in this genus have an unusually high concentration of it.

In 1994 tobacco companies sent to the US Government’s Department of Health and Human Services a list of 599 of the additives they were putting in cigarettes. These are all approved by the FDA as food additives, but when burned in a cigarette—which the FDA’s approval does not take into account—their properties change, typically for the worse. The result is the creation of thousands of chemical compounds, some of which are toxic and/or known or possible human carcinogens—cancer-causing agents.

Below is just a small selection of some of the many additives and chemical compounds found in cigarettes and/or created by burning cigarettes and found in smoke:

  • Acetone: This chemical compound is the active ingredient in paint thinner and nail polish remover, and is used to make a number of other chemicals.
  • Acrolein: This organic chemical compound is used to prepare things like polyester resin. it was at one time considered a possible human carcinogen by the EPA, but that classification has been withdrawn .
  • Anabasine: A nicotine receptor agonist toxin, in high doses this minor tobacco alkaloid can be toxic and cause death. It is often used as an industrial insecticide.
  • Ammonia: This nitrogen/hydrogen compound used in refrigerants, disinfectants, and fuel, and when oxidized to create nitric acid, is used to make fertilizers and explosives.
  • Carbon Monoxide
  • Chromium: This hard metal chemical element and its compounds have dozens of industrial applications, such as chrome plating, as an alloy constituent, and in creating dyes and paints.
  • Glycerol: This chemical compound is used to make products smoother, such as soap, cough syrup, shaving cream, and a variety of skin and hair care products.
  • Hydrogen Cyanide: This extremely poisonous chemical compound is used to temper steel and make explosives, among other things. It was also employed by the Nazis (as Zyklon B) to exterminate civilians in the gas chambers.
  • Lead: This heavy metal element is used in dozens of industrial ways, in making such things as lead-acid batteries, bullets, and in building construction. It is a neurotoxin that over time can build up in human soft tissues and damage the nervous system.
  • Mercury: This heavy metal chemical element has numerous industrial applications, from cosmetics to laboratory instruments. As an element and compound, mercury is extremely toxic to humans.
  • Nicotine: Nicotine is a naturally occurring alkaloid chemical compound found in tobacco, coca, and some other vegetables in smaller quantities, like green pepper. It is a neurotoxin, meaning that it acts on the nerve cells of biological organisms. Most venoms are neurotoxins, and in fact nicotine is a sufficiently good neurotoxin against insects that it has been used as a insecticide.
  • Nornicotine: A secondary tobacco alkaloid, nornicotine possibly enhances a cigarette’s addictive qualities and it may play a hand in smokers developing Alzheimer’s disease and age-related macular degeneration.
  • Propylene glycol: the FDA regards this as as safe food additive. It is also found in some medicines, cosmetics, toothpaste, mouthwash, and sexual lubricants.
  • Selenium: This chemical element has a low toxicity (unless in high doses), but as a compound—notably as selenate and selenite—it is comparable to arsenic.
  • Tar: You have seen and heard this term attached to cigarettes—i.e. low-tar—but what does it mean? In this case, tar is the catch-all term used to describe the full range of a cigarette’s toxic chemicals. When you finish a smoke, look at the end of the filter you’ve had in your mouth; the brown stain you see is the tar. Look at your teeth; the slight discoloration from white to a brownish off-white is the tar. Use a clear jar to extinguish your cigarettes for a day—the thick, disgusting black goop you see is largely the tar. Now, imagine all that in your lungs, your throat, and throughout your mouth.
  • Triacetin: This artificial chemical compound is used as a food additive and as a fuel additive in gasoline and biodiesel.
  • Triethylene glycol: An organic compound also found in vinyl, engine coolants, and hydraulic and brake fluids.

Cancer-causing chemicals

The following chemicals found in cigarettes or second-hand smoke are classified as human carcinogens by one or more of a variety of established and credible health or environmental organizations, such as the US Environmental Protection Agency or the International Agency for Research on Cancer (IARC) , part of the World Health Organization. Repeated exposure to any one of these chemicals is believed to have the ability to cause cancer in both humans and lab test animals.

Keep in mind that this list is not complete; research has uncovered as many as 50 carcinogenic chemical compounds.

  • Acetaldehyde: This organic chemical compound has a number of applications, mostly as a chemical intermediate to produce other chemicals. The US EPA considers it a probable human carcinogen.
  • Arsenic: This chemical element (As, atomic number 33) is extremely poisonous to humans and other biological life forms, which explains why it is used effectively in pesticides, herbicides insecticides, and in the food of occasional human poisoners. The IARC considers it a known human carcinogen.
  • Benzene: This chemical compound is used in small amounts to make such things as rubbers, dyes, detergents, explosives, and pesticides. The IARC considers it a known human carcinogen.
  • Benzo[a]pyrene: This compound is a product of incomplete combustion and is found in automotive exhaust and tobacco smoke. The International Labour Organization considers it a known human carcinogen.
  • Cadmium: This chemical element and its compounds are known carcinogens in humans. Cadmium is used in the manufacture of batteries and paint pigments. The IARC considers it and its compounds a known human carcinogen.
  • Formaldehyde: Best known as a solution used in embalming and preserving human remains, this chemical compound has numerous applications, from a disinfectant to producing other chemicals. The IARC considers it a known human carcinogen.
  • Nickel: This metallic chemical element is used in stainless steel, magnets, coins, and some alloys. In the form of nickel sulfide fumes (i.e. compounds), it is regarded as a known human carcinogen by the IARC, and as the gas nickel carbonyl it is very toxic to humans.
  • Styrene: This chemical compound is the precursor to polystyrene, used to make a wide variety of plastics. The IARC regards it as a possible human carcinogen.

Related Articles

Benefits of Quitting Smoking

Quit Smoking Support

Smoking Effects

Facts about Nicotine

Where Does Nicotine Come From?

What Can Smoking Cause?

Low Tar Cigarettes?


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