Toxic chemicals in tobacco smoke

Your lungs cannot protect you from the toxic and cancer-causing chemicals in smoke. Learn more about these chemicals and how they can affect you.

What is cigarette smoke?

Cigarette smoke is made of chemicals that float in gases.

There are over 7,000 different chemicals in cigarette smoke. Almost 100 of these are known to be toxic. They are present at doses that are poisonous to humans.

An average smoker takes 12 puffs per cigarette and smokes 13 cigarettes per day. That’s 156 lung-fulls of smoke per day, and almost 57,000 thousand lung-fulls of smoke each year.

Toxic chemicals in smoke come from a few different sources:

  • Some come from the tobacco plant, such as
    • cadmium and lead from the soil
    • nitrates from fertilisers.
  • Other toxic chemicals come from the curing and processing of tobacco, such as tobacco-specific nitrosamines which form during the curing process.
  • Most of the toxic chemicals in tobacco smoke are created when the tobacco is burned during smoking.

Find more information about the chemicals in smoke

Cigarette smoke is full of toxic and cancer-causing chemicals

Almost 100 chemicals in smoke are toxic. They are present at doses that are poisonous to humans. At least 70 of the poisonous chemicals in tobacco smoke are known causes of cancer. Many of these chemicals cause damage to DNA.

DNA contains the blueprint to produce more cells. Chemicals from smoke can damage your DNA, forming mutations in your genes. These mutations are the triggers that start the cancer growing. 

Learn more about each toxic chemical:

Formaldehyde

Formaldehyde is a chemical used to preserve dead bodies. It’s toxic to the airways and causes cancer.

Acrolein

Acrolein is made when burning petrol, wood and plastics. Acrolein is produced by burning the sugars in tobacco. Acrolein irritates your respiratory tract, weakens your immune system and causes serious heart damage and disease.

Lead

Lead is a toxic metal that is banned in petrol. Lead can cause cancer and damages the cardiovascular system.

Benzene

Benzene is a toxic chemical that is also found in crude oil, petrol and paint stripper. Contact with even small amounts of benzene is dangerous and can cause cancer.  

Benzene from cigarette smoke is the likely cause of leukemia. It may also reduce fertility.

4-Aminobiphenyl

This chemical was once used in making dyes. Its production was banned in the United States in the 1950s due to its risk of causing cancer. 4-Aminobiphenyl from cigarette smoke is believed to be a cause of bladder cancer in people who smoke.

Carbon monoxide

This gas in cigarette smoke causes heart damage that may lead to a heart attack. It is also found in car exhaust.

Ammonia

This industrial cleaner is commonly added to tobacco by the manufacturers.

1,3-Butadiene

This toxic chemical found in smoke damages the reproductive system.

Polycyclic aromatic hydrocarbons

These chemicals form when tobacco is burned. They are known to damage DNA. There are at least 16 different types found in cigarette smoke that cause cancer.

Nitrosamines

These chemicals cause cancer, such as cancer of the lungs, mouth, and pancreas. Even small amounts are dangerous. Some are also called tobacco-specific nitrosamines. 

Furan

Furan is a toxic chemical used to make agricultural chemicals such as insecticides (bug killers). It can cause liver disease and liver cancer.

Arsenic

Arsenic is a poison found in tobacco smoke. Arsenic is a known cause of cancer but also damages the cardiovascular system and reproductive system.

Hydrogen cyanide

Hydrogen cyanide is a toxic gas that damages the lungs and the cardiovascular system.

Your lungs cannot protect you from all the chemicals in smoke

Your lungs are designed to collect oxygen from air. Oxygen moves from your lung cells straight into your blood stream. Toxic chemicals breathed in with tobacco smoke do the same.

Every time you inhale, smoke enters your body. Toxic chemicals from smoke:

  • fill your mouth
  • enter the cells of your lips and tongue
  • enter your tonsils and salivary glands
  • enter the cells in your throat
  • enter your voice box
  • fill your lungs.

Smoking causes cancer in every one of these body parts, but the smoke does not stop there. With every breath of smoke, toxic chemicals move from your lungs into your blood stream. In your blood, they spread all around your body.

Toxic chemicals from smoke have been found in many different parts of the bodies of people who smoke. Some examples include:

Saliva

Signs of nicotine and cyanide are found in the saliva of people who smoke.

Breath

Benzene and carbon monoxide are found in the breath of people who smoke.

Urine (wee or pee)

Signs of nicotine, alkaloids and amines from smoke are found in the urine of people who smoke.

Blood

Blood from people who smoke contains the toxic heavy metal cadmium and signs of cyanide. Chemicals called furans, benzene and cancer-causing tobacco-specific nitrosamines are also found in the blood of people who smoke.

Lungs

Polycyclic aromatic hydrocarbons, which cause cancer, are found in the lungs of people who smoke.

Cervix

The cervix is part of the female reproductive system. Tobacco-specific nitrosamines and benzo[α]pyrene are found in the cervical mucus of people who smoke.

Pancreas

Cancer-causing tobacco-specific nitrosamines are found in the pancreases of people who smoke. The pancreas is a digestive organ.

Semen

The toxic heavy metal cadmium is found in the semen of people who smoke. This means that non-smoking partners of male smokers may also be exposed to cadmium.

Placenta

High levels of toxic cadmium are found in the placenta of women who smoke. The placenta provides oxygen and nutrients to the baby from the mother.

Toenails

Nicotine from cigarettes spreads so far, that signs of it are even found in toenails.

Quitting smoking reduces your exposure to toxic chemicals

If you are an average 13 cigarette per day smoker, quitting smoking means 56,940 lung-fulls of toxic chemicals no longer entering your body every year.

When you stop smoking, your body can start to recover from the damage that has built up with every cigarette. Quitting at any age improves your health and quality of life.

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