Cigarette Toxins

Cigarettes: the smoke and the fire

Years ago, people knew that cigarettes contained nicotine and tar. Other cigarette toxins were not known, or perhaps simply not discussed.

The tobacco plant’s nicotine may help protect it from insect predators, although it is not invulnerable to all insects. In small doses, nicotine increases your heart rate. In large doses, it is a poison.

Tobacco plants can be processed into an organic pesticide.

Tar is the brown gunk that stains your fingers and teeth. It also damages the cilia – the hair-like “brooms” that sweep microbes and debris out of your airways. Did you cough during your first smoke? That was your body doing its job keep your lungs clean. Regular smokers don’t cough like that; and that is a sign of damage. Tar is also a known carcinogen in humans. It may be one of the main cigarette toxins our bodies need to contend with, but not the only one.

Carbon dioxide, carbon monoxide and water (vapour) are the end products of burning fibres such as tobacco. The carbon monoxide is created because of the low oxygen-to-carbon ratio inside the cigarette. Normally, you breathe to bring oxygen in, and to move carbon dioxide out. Breathing in the carbon monoxide reduces your supply of oxygen.

The other chemicals

The U.S. FDA made headlines in January and February of 2010: it will ask the tobacco companies to provide cigarette ingredient lists. Wait for June 2011 for the FDA to publish the harmful ingredients, by brand and quantity.

If you don’t want to wait for the FDA, others have claimed at least 599 chemicals are in cigarettes. Check out this list of cigarette toxins.

Five chemicals are named in several different lists, including England’s BBC:

Acetone
Ammonia
Arsenic
Butane
Hydrogen cyanide

The U.S. Department of Health and Human Services’ eleventh report on carcinogens includes many cigarette components:

Acetaldehyde is suspected to be a carcinogen, but this has not been established. It has a fruity odor at low concentrations. It is released by cigarettes, marijuana, and burning wood. Inhaling the smoke might contribute to cancer. Acetaldehyde is a natural component of various fruits and vegetables (apples, broccoli and many other foods), and occurs naturally in tobacco leaves.
Ammonia is found in tobacco smoke. It is an irritant, but not a carcinogen.
niline is found in tobacco smoke. The British MSDS (Material Safety Data Sheet) says it is a possible carcinogen, and toxic in appreciable quantities.
Arsenic is a known carcinogen. It is found in tobacco smoke, food, contaminated water, and in a variety of industrial processes.
Benzene is a known carcinogen. Half the USA’s exposure to benzene is through cigarette smoke.
Cadmium is a known carcinogen. Non-smokers are exposed mainly through food; smokers take in more through smoking.
Formaldehyde, as a gas, is suspected to be a carcinogen, but this has not been established. It is produced by combustion: the report includes power plants, automobiles, wood stoves, and cigarettes. Since formaldehyde degrades fairly quickly in the environment, cigarettes may be a significant source for the smoker. (You may remember liquid formaldehyde as the preservative for biology specimens).
Sulphur dioxide is a gas found in tobacco smoke. The Oxford ‘HSci’ project says it is an irritant, may aggravate asthma, and is toxic in high concentrations.
Vinyl chloride is a toxin, and a known carcinogen. Although it is used in making PVC plastic, most people have extremely limited exposure to vinyl chloride. The main risk factors are: living near a factory with poor emission control; and smoking.
Environmental tobacco smoke, itself, is a known carcinogen. This is “second-hand” smoke.

E-cigarettes

The recently-introduced “e-cigarette”, or electronic cigarette, has a battery and a heater.

It vaporizes nicotine and aromatic chemicals that the user inhales. They are marketed as being safer than tobacco-burning cigarettes, helping us to avoid most cigarette toxins. However, a July 22, 2009 news release from the U.S. FDA (Food and Drug Administration) gives several warnings, including:

First, the FDA had not fully tested this product, which had not then been submitted for approval.
E-cigarettes contain nicotine, which is addictive.
Some e-cigarettes contain known carcinogens.
Some e-cigarettes contain toxins such as diethylene glycol, an ingredient in antifreeze.

It seems early to make a more definitive report. One danger with the e-cigarette is that it is a ploy to entice young people to begin using nicotine. On the other hand, it might be a long-time smoker’s weapon in the fight to quit.