The Quick Answer
Over 4000 chemicals. Over 60 of which are carcinogenic. Think about that as being like a can of coke – you look at the ingredients list to see a very long list of 4000 E-numbers – 60 of which are in red because they are cancer causing. Would you drink 20 cans a day?
The Illustrated Answer
The Technical Answer
Below are a sample of some of the chemicals found in cigarettes. Click on one to learn how it affects you.
This information has been used with kind permission of the authors at Physicians for a Smoke Free Canada.
- Ammonia possesses a sharp, irritating odor
detectable as low as 1 ppm.
- At high concentrations, ammonia causes
intense irritation, severe eye damage, and asthma.
- 2-aminonaphthalene causes cancer in
- There is no safe exposure limit for
- Absorption of 2-aminonaphthalene occurs
both by inhalation and through the skin.
- Because it causes cancer, the industrial
use of 2-aminonaphthalene is restricted or banned.
- 1-aminonaphthalene has been shown to cause
lung, liver and leukemia cancers in animals.
- 1-aminonaphthalene may cause cancer in
- 1-aminonaphthalene has been shown to have
moderate toxicity in fish.
- Absorption occurs both by inhalation and
through the skin.
- Absorption through the skin may occur
without a sense of irritation or other warning.
- The main industrial uses of
1-aminonaphthalene include dyes, rubber, and weed control.
- 4-aminobiphenyl is confirmed to cause
cancer in humans.
- The carcinogenic nature of 4-aminobiphenyl
has been known since at least 1974.
- This chemical has been called ‘one of the
most potent known bladder carcinogens’.
- There is no known safe level of
- Absorption occurs through the skin.
- 4-aminobiphenyl is no longer produced on a
commercial scale for use in industry.
- 3-aminobiphenyl is a mutagen, and causes
mutation in microorganisms.
- Benzo[a]pyrene (B[a]P) is suspected to
cause cancer in humans.
- There is a significant correlation between
B[a]P exposure and lung cancer mortality.
- B[a]P was found to cause cancer in animals
and fish in every study to date.
- Animal studies showed that as low a dose
as 0.05 mg B[a]P caused tumors.
- B[a]P deposits in the lung. Elimination of
B[a]P from the lung is severely restricted by cigarette smoking.
- Cancer is more likely to occur with
repeated B[a]P exposures than with a single dose of the same amount.
- B[a]P exposure may also cause skin cancer,
dermatitis, photoallergy, non-neoplastic respiratory disease and emphysema.
- Exposure to B[a]P results in decreased
reproductive capacity for both males and females.
- Absorption of B[a]P also occurs through
- Formaldehyde is suspected to cause cancer
- Formaldehyde occurs naturally at 0.12 to
0.38 parts per BILLION [ppb]. Sidestream smoke increases this by 0.23 to 0.27 parts per
MILLION [ppm] (a 1000+ increase).
- Long-term exposure at levels greater than
0.1 ppm appears to be a risk for cancers of the lung, pharynx, buccal cavity, liver, bone,
skin, prostate gland, bladder, kidney and eye, leukemia and Hodgkin’s disease.
- Animal studies showed formaldehyde is an
irritant to eyes, nose, throat and lungs, and causes cellular changes in the upper
respiratory tract, a decrease in respiratory rate, and adversely affects the liver.
- Formaldehyde exposure greater than 0.22
ppm is linked to respiratory symptoms such as cough, phlegm, chronic bronchitis, asthma,
shortness of breath and chest colds.
- Formaldehyde is known to produce allergic
reactions and induction of asthma-like conditions, lightheadedness, dizziness, diminished
dexterity, itching eyes, dry and sore throats, disturbed sleep, unusual thirst, and
malignant disease in humans.
- Human eyes are sensitive to formaldehyde
at concentrations of 0.01 ppm, and are irritated by formaldehyde at concentrations of 0.05
to 0.5 ppm.
- The main uses of formaldehyde in industry
include fertilizer, dyes, disinfectants, germicides, preservatives, and embalming fluid.
- Studies have shown that acetaldehyde
causes cancer in animals, and may cause cancer in humans.
- Small amounts of acetaldehyde irritate the
eyes, skin, and respiratory tract of humans and animals.
- Animal studies in which pregnant rats were
exposed to acetaldehyde found that acetaldehyde interfered with the exchange of nutrients
from the mother to the placenta, resulting in growth retardation, malformation, delayed
bone growth and death of the fetus.
- Acetaldehyde may increase the absorption
of the other hazardous chemicals in tobacco smoke into the bronchial tubes.
- The main industrial uses of acetaldehyde
include silvering of mirrors, leather tanning, fuel, glue, dyes, plastics and synthetic
- Acetaldehyde decomposition products
include carbon monoxide.
- Acetone is an irritant to eyes, nose and
- Acetone irritates, dries, and may burn
- Absorption occurs both via inhalation and
through the skin.
- Higher doses can cause dizziness,
lightheadedness, damage to the liver and kidneys.
- Acrolein has not been found to cause
cancer. However, in the body, acrolein produces glycidaldehyde which does cause cancer.
- Long term inhalation studies on animals
found that acrolein causes emphysema and inflammation of the lung, liver and kidney.
- Acrolein is intensely irritating to the
eyes and upper respiratory tract in human and animals. Acrolein is 5 times stronger an
irritant than formaldehyde, acetaldehyde or crotonaldehyde (all of which are found in
- The main industrial uses of acrolein
include polyurethane manufacture, polyester resins, herbicides and tear gas.
- Inhalation of propionaldehyde causes
severe irritation of the respiratory system.
- Propionaldehyde causes irritation to skin
- Crotonaldehyde is known to cause cancer in
- Crotonaldehyde causes cancer by
interfering with DNA function (a genotoxic carcinogen).
- Crotonaldehyde is a fast-acting (within
seconds) irritant to the nose and upper respiratory tract.
- The main use of crotonaldehyde in industry
is as a warning agent in fuel gases.
- Methyl ethyl ketone causes nose, throat,
and eye irritation in humans at moderate levels.
- The odor of methyl ethyl ketone is
detectable at 10 ppm.
- The main uses of methyl ethyl ketone in
industry include solvents, resins, artificial leather, rubbers, lacquers, varnishes and
- Butyraldehyde is an irritant to eyes,
nose, throat and lungs.
- Higher doses of butyraldehyde causes
dizziness and lightheadedness, and may burn skin.
- The main industrial uses of butyraldehyde
include resins, solvents and plasticizers.
- Hydrogen cyanide causes nasal irritation,
confusion, headache, dizziness, weakness and nausea in humans at moderate doses.
- At higher doses, hydrogen cyanide causes
asthenia, vertigo, loss of weight and gastrointestinal problems.
- The main uses of hydrogen cyanide in
industry include fumigation, as an insecticide, electroplating, metallurgy and
- Inhalable, insoluble nickel is confirmed
to cause cancer in humans.
- Up to 5% of the general population are
sensitized (allergic) to nickel.
- Nickel inhalation increases the risk of
cancer or of gastrointestinal symptoms.
- Exposure to inhalable nickel may result in
chronic irritation of the upper respiratory tract or bronchial asthma.
- Nickel inhalation exposure increases
susceptibility to respiratory infection, allergic contact dermatitis, and pulmonary edema.
- The main uses of nickel in industry
include production of stainless steel, alloys, electroplating, coinage, and alkaline
- Lead is known to cause cancer in animals.
- Lead may cause cancer in humans.
- Lead is toxic, and soluble in body fluids
- Lead interacts with enzymes, especially
those associated with heme synthesis (blood).
- Absorption of low levels of lead causes an
increase in blood pressure in humans.
- Lead causes anemia at blood levels above
- Lead poisoning effects on the brain may
not be reversible.
- Long term exposure to lead may lead to
- Lead is a possible Reproductive Toxin.
- Lead may affect sperm formation (at
greater than 11.9 ug/dl blood lead).
- Lead exposure affects the development of
fetuses. Children who were exposed to blood lead levels of greater than 10 ug/dl in the
womb have been found to have developmental effects such as depressed intellectual
- Air to blood lead levels: 0.03 to 0.19
ug/dl blood per mg/m3 of lead in air.
- The main uses of lead in industry include
alloys (solder, bronze, brass), paint pigments, storage batteries, glass, plastics,
- Cadmium is confirmed to cause cancer in
- Cadmium primarily targets the kidneys.
- Chronic cadmium exposure is linked to
gastrointestinal symptoms, anemia, rhinitis, discoloration of teeth, microfractures,
pulmonary emphysema and kidney disease.
- The main industrial uses of cadmium
include metal coatings, bearings, reactor control rods, storage batteries, television
phosphors, semiconductors, pigments, and dry film lubricants.
- Cr VI compounds are recognized to cause
- Cr VI compounds can easily pass into the
cell through the cell membrane.
- Cr VI compounds are sensitizers, and can
therefore induce an allergic reaction in some individuals.
- Nitric oxide reacts with haemoglobin to
hinder oxygen uptake in the blood.
- Nitric oxide reacts with haemoglobin 1400
times more effectively than carbon monoxide reacts with haemoglobin.
- The toxicity of nitric oxide when combined
with carbon monoxide (also in tobacco smoke) is additive.
- Pyridine vapour causes eye and upper
respiratory tract irritation in humans.
- Exposure to pyridine results in an
increased production of blood platelets.
- Longer duration exposure to pyridine
causes nausea, headache, insomnia, nervousness, and abdominal discomfort in humans.
- The disagreeable odor of pyridine is
detectable at less than 1 ppm.
- The main industrial uses of pyridine
include solvents, pesticides and resins.
- Quinoline causes genetic mutations
(mutagen) and therefore may increase your risk of cancer.
- Repeated exposure damages the retina of
the eye, affecting vision.
- Repeated exposure to quinoline may damage
- Quinoline exposure may lead to allergy,
with rash and itching (sensitizer).
- Quinoline is irritating to the eyes, nose,
throat and bronchial tubes, and may cause sore throat, nose bleeds, cough and phlegm.
- Absorption occurs both by inhalation and
through the skin.
- Quinoline bioaccumulates in the tissues of
- The main industrial uses of quinoline
include dyes, catalysts, insecticides, herbicides, corrosion inhibitors and to preserve
- Exposure to hydroquinone leads to eye
injury, skin irritation and central nervous system effects in humans.
- The main uses of hydroquinone in industry
include rubber production, photography, paints, varnishes and in motor fuel.
- Resorcinol was found to be irritating to
skin and eyes in humans.
- The main industrial uses of resorcinol
include tanning, photography, resins, dyes, laminates and adhesives.
- Catechol, when inhaled with benzo[a]pyrene
(also found in tobacco smoke), is co-carcinogenic.
- Catechol causes increased blood pressure,
upper respiratory tract irritation and eczematous dermatitis in humans.
- At higher doses, catchol causes kidney
damage and convulsions.
- The main uses of catchol in industry
include photography, rubber, dye, oil, insecticides, and inks.
- Studies have shown phenol to be toxic to
the respiratory, cardiovascular, hepatic, renal and neurological systems of animals.
- Higher doses of phenol may damage the
lungs and central nervous system and induce convulsions in humans.
- Phenol is irritating to the skin, mucous
membranes and eyes in humans.
- Phenol may be absorbed by inhalation or
through the skin.
- The main industrial uses of phenol include
chemicals and drugs, disinfectants, germicidal paints and slimicides.
- Cresol was found to promote tumors in
- Cresol is strongly irritating to skin, and
causes dermatitis in humans.
- Long term exposure to cresol leads to
headaches, nausea, vomiting, elevated blood pressure, impaired kidney function,
blood-calcium imbalance and marked tremors, in humans.
- Cresol is absorbed through the skin.
- The main uses of cresol in industry
include ore flotation, disinfectants, synthetic resins, dyes, fumigants, and explosives.
Tar is the tobacco industry term for all
non-gaseous, non-nicotine, non-water chemicals in tobacco smoke.
- Free-base nicotine (in tobacco smoke) is
absorbed almost instantly by inhalation, ingestion and skin contact.
- Nicotine concentrates in the brain, the
kidney, the stomach mucosa, the adrenal medulla, the nasal mucosa and the salivary glands.
- Studies show that nicotine exposure can
result in seizures, vomiting, depressions of the central nervous system, growth
retardation, developmental toxicity in fetuses, and preterm birth with reduced body weight
and brain development in animals.
- Nicotine is excreted in breast milk.
- Mild nicotine poisoning in humans results
in the following symptoms: vomiting, diarrhea, increase in respiration, heart rate, blood
pressure, headache, dizziness, and neurological stimulation.
- Nicotine is considered responsible for
many of the acute psychological and physiological effects of smoking, chewing or inhaling
- The main uses of nicotine in industry
(besides tobacco) include insecticides (now mostly banned) and as tranquilizing darts for
- Tobacco Smoke is the major source of
personal inhalation of carbon monoxide.
- Carbon monoxide is absorbed into the
blood, resulting in reduction in exercise tolerance, increased angina and headaches.
- Carbon monoxide binds to haemoglobin,
reducing the oxygen-carrying capacity of the blood.
- As little as 3% absorbed carbon monoxide
in haemoglobin results in decreased psychomotor function, and therefore can impair driving
skills. Headaches may occur at 10% carbon monoxide in haemoglobin.
- Carbon monoxide binds to myoglobin,
decreasing heart and muscle function.
- Carbon monoxide is a possible Reproductive
- Studies on pregnant animals show decreased
birth weights, fetal death or damage at moderate levels of carbon monoxide.
- Fetal carbon monoxide levels are generally
10 to 15% higher than maternal levels.
- Inhaled tobacco smoke increases the level
of carbon monoxide in the fetus, increasing the chance of low birth weight, and possible
perinatal death or retardation of mental abilities.
- 1,3-butadiene suspected to cause cancer in
- Joint exposure to styrene (also found in
tobacco smoke) may increase the risk of disease.
- The toxicity of 1,3-butadiene is increased
by prolonged or repeated exposures.
- The main industrial uses of 1,3-butadiene
include synthetic rubber and tire manufacture.
- Isoprene causes skin, eye and mucous
- Acrylonitrile is suspected to cause cancer
- Acrylonitrile is highly toxic. It is
similar to cyanide in toxicity, and is also known as ‘vinyl cyanide’.
- Absorption of acrylonitrile is from the
respiratory and gastrointestinal tract and through the skin.
- Studies on pregnant animals showed ‘a
significant maternal toxicity’, leading to increased possibility of deformation in the
fetus and offspring.
- The main industrial uses of acrylonitrile
include manufacture of bottles and as a fumigant for tobacco.
- In the United States, acrylonitrile has
been withdrawn as a fumigant for all other food commodities.
- Benzene is confirmed to cause cancer in
- Benzene is known to cause leukemia in
- Cumulative exposure to benzene is the most
likely predictor of the possibility of developing leukemia.
- Leukemia may manifest 2 to 50 years after
exposure to benzene.
- Benzene is highly toxic.
- Benzene produces chromosomal aberrations
in humans and in animals.
- Benzene is absorbed through the skin.
- Previously, benzene was used in industry
to manufacture inks, rubber, lacquers and paint remover.
- Toluene is highly toxic.
- Toluene is a possible Reproductive Toxin.
- Inhaled toluene appears in blood
circulation within 10 seconds and accumulates in body fat.
- Toluene is a depressant to the central
nervous system in animals and in humans.
- Long term low level exposure results in
headaches, lassitude, loss of appetite, disturbances in menstruation, reductions in
intelligence and psychomotor skills.
- Higher exposure results in encephalopathy,
headache, depression, lassitude, impaired coordination, transient memory loss, impaired
reaction time, dizziness, nasal discharge, drowsiness, and metallic taste.
- The main uses of toluene in industry
include rubbers, oils, resins, adhesives, inks, detergents, dyes, and explosives.
- Styrene is a possible human carcinogen.
- Styrene has been found to produce
headaches, ocular and conjunctival irritation and slowed reaction time, fatigue, dizziness
and nausea, reduced attention and manual dexterity, and reductions in colour
discrimination, in humans.
- Reproductive effects of styrene include a
possible increased incidence of spontaneous abortion and increased number of abnormal
- When styrene and butadiene (also in
tobacco smoke) are combined, they produce 4-phylglycolhexene, a suspected sensitizer.
- The main industrial uses of styrene
include plastics, coatings, polyesters, resins, and synthetic rubbers.
- NNN (N-nitrosonornicotine) is a
carcinogenic Tobacco-Specific Nitrosamine (TSNA) found only in tobacco products.
- NNN is formed from nicotine directly and
is the most abundant cancer-causing TSNA.
- NNN is a yellow, oily liquid that is known
to cause nose, throat, lung and digestive tract cancer in animals.
- NNN may cause reproductive damage in
humans.-These is no safe level of exposure to NNN.
[(4-methylnitrosamino)-1-(3-pyridyl)-1-butanone] is a carcinogenic Tobacco-Specific
Nitrosamine (TSNA) found only in tobacco products.
- NNK is a powerful lung carcinogen.
- NNK induces adenoma and AC tumors of the
- There is no safe level of exposure to NAT.
- NAT (N-nitrosoanatabine) is a possibly
carcinogenic Tobacco-Specific Nitrosamine (TSNA) found only in tobacco products.