Radioactive Cigarette Smoke

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Most people, smokers and non-smokers alike, are surprised to learn that cigarette smoke contains radioactive particles, and are even more shocked to find that when inhaled, these particles lodge in the lungs and stay there.

What are these toxins and how do they get into cigarettes?

Lead-210 (Pb-210) and polonium-210 (Po-210) are poisonous, radioactive heavy metals that research has shown to be present in tobacco smoke.

Where Lead-210 and Polonium-210 Come From

When uranium, an ore that occurs in small amounts in nature, breaks down, radium is released as radon gas into the atmosphere. Once that occurs, radon gas decays quickly, producing lead-210 (Pb-210) and polonium-210 (Po-210), highly radioactive metals (known as radon decay products). Radium is also present in phosphate fertilizers that are often used in tobacco farming.

How Lead-210 and Polonium-210 Get Into Tobacco

As radium in the soil around tobacco plants releases radon gas, tiny lead and polonium particles float free and attach to bits of dust that are carried to the surface of tobacco leaves. And because tobacco leaves are covered with thousands of fine hairs, these radioactive chemicals grab hold and stay put from the field to the processing plant.  

Once there, cleaning of the tobacco leaves doesn't remove them because Lead-210 and polonium-210 are both insoluble in water, so they remain in the finished product that goes out to consumers, ultimately finding a home in smoker's lungs.

When a Smoker Inhales Radioactive Metals

As a smoker breathes in cigarette smoke, lead-210 and polonium-210 "stick" to the cigarette tar that collects at the junctions of air passages within the lungs called bronchioles. Studies have shown that lead-210 and polonium-210 build up at these locations and over time produce radioactive hot spots.

Health Risks Associated with Lead-210 and Polonium-210

Researchers believe that inhaling lead-210 and polonium-210 is a significant risk factor for lung cancer because the build up of radioactive particles in the lungs of smokers is cumulative and permanent. 

Radioactive Secondhand Smoke, Too

Anyone who breathes in secondhand smoke exposes their lungs to the same toxic heavy metals that are associated with causing lung cancer in smokers. 

Further, these toxins are just two of the hundreds of poisonous and/or carcinogenic chemicals present in cigarette smoke.

There is no safe level of exposure to secondhand smoke (or mainstream, for that matter.)  Steer clear of it and if you're a smoker, use the resources below to help you get started with smoking cessation.

Smoking offers you nothing other than disease and ultimately, death.

Quit smoking now.

More on the Chemicals in Cigarette Smoke

To date, scientists have discovered more than 7,000 chemicals, including 250 poisonous and 70 carcinogenic compounds in cigarettes / cigarette smoke.

Resources to Help You Quit Smoking:

Learn what you can expect when you quit smoking and how to minimize the discomforts associated with nicotine withdrawal. The links below will help you get started.


Polonium Factsheet Centers for Disease Control and Prevention.

Tobacco Smoke - Radiation Protection. Accessed 11 March, 2009. Environmental Protection Agency

Lead-210 in Tobacco and Cigarette Smoke September, 1967. PubMed Central - National Institutes of Health.

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