What’s in Tobacco Smoke

Tobacco smoke is made up of over 7000 chemical compounds, including 70 known carcinogens, such as formaldehyde, total oxidized nitrogen, hydrogen cyanide, cadmium and other heavy metals.¹

Substances in tobacco smoke can be found in either particulate or gaseous form. Nicotine and tar are some examples of those found in particulate form while the gaseous substances found include carbon monoxide, carbon dioxide, hydrogen cyanide, nitrogen oxides, volatile sulfur compounds, volatile hydrocarbons, nitriles, alcohols, aldehydes and ketones.

Nicotine is the substance responsible for the addiction that develops from tobacco use. It is less toxic in comparison with other tobacco components. The tar in cigarettes is made up of a combination of various substances, some of which are carcinogenic such as polycyclic and aromatic hydrocarbons.

Tar is what remains after nicotine and moisture are removed. It is a combination of many carcinogenic substances and appears dark in color and has a sticky texture. It enters the mucous membranes of the mouth, lungs, stomach and intestine, causing various cancers of these areas, but also emphysema and other chronic respiratory and systemic diseases.

Carbon monoxide is a very toxic substance found in cigarette smoke. As it has greater affinity for binding to haemoglobin than oxygen, it prevents oxygen exchange in the lungs and then to the blood, preventing oxygen transport throughout the body. It also makes it more difficult for the body to eliminate carbon dioxide. Thus, chronic tissue damage is also caused by this phenomenon. The amount of carbon monoxide contained in cigarette smoke is at least as high as that of a non-catalytic gasoline engine.

1. US Centers for Disease Control and Prevention. Smoking and Tobacco Use Fact Sheet, Secondhand Smoke. https://www.cdc.gov/tobacco/data_statistics/fact_sheets/secondhand_smoke/general_facts/index.htm.
   Published 2018.