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Cancer Prevention: What You Need To Know

Radiation Exposure:
The Facts vs. Fiction

Naturally Occurring Background Radiation
Naturally occurring radiation has nothing to do with radioactive fallout from nuclear weapons or nuclear power plant accidents. Our universe and solar system is and always has been radioactive. We live in a naturally radioactive world. Background radiation accounts for an individual receiving, on the average, about 300-350 mrem each year. For example, a cross country airplane flight results in a dose of 4 mrem per trip. A routine chest x-ray is about 10 mrem per film. Smoking 1.5 packs of cigarettes daily exposes the individual to about 1300 mrem per year.

Other Sources of Radiation
Besides natural background radiation, there exist additional sources of radiation exposure, many of which depend upon a person’s lifestyle and the number of medical tests and therapies they may receive.

Cigarette Smoking
Besides carbon dioxide, tar, and nicotine, cigarette smoke also contains radioactive lead and polonium, enough to result in a radiation exposure of 1300 mrem/year to a 1.5 pack a day smoker. Each cigarette smoked can also be equated to one chest x-ray, and a non-smoker living with a smoker may receive the equivalent of 12 chest x-rays per year as a result of second-hand smoke. Perhaps the easiest radiation exposure to control is this one: If you smoke, stop; if you don’t smoke, don’t ever start. Whenever possible, minimize your exposure to other people’s smoke. For more information about smoking, see the Quitting Smoking Fact Sheet.

Radon
Radon is a naturally occurring odorless, tasteless, colorless radioactive gas. It is produced by the natural breakdown of uranium and radium in soil, rock, and water. Many homes and other buildings such as schools and offices have high levels of radon. Exposure to high levels of radon constitutes an important health hazard. For more information about radon, see the Radon Fact Sheet.

Medical Radiation Exposures
The benefits of diagnostic x-rays and cancer therapies are almost always greater than any risk that the radiation exposure may carry. Ask your doctor to explain the benefits and risks to you, so that you can make a knowledgeable choice. A necessary treatment should not be refused just because it may result in a radiation exposure. However, always notify your doctor and the x-ray technologist if you think you might be pregnant before having the exam or therapy.

Food Irradiation
Food irradiation preserves food by killing insects, parasites and some forms of bacteria and yeast as well as inhibiting spoilage by retarding the ripening of fruit. This process is an alternative to chemical preservatives and can reduce the use of pesticides. Irradiated food itself is not radioactive, and causes no radiation exposure to a consumer. Sealed, treated foods can be kept at a room temperature for years and the irradiation does not create any toxins in the food. Some of the foodstuffs preserved by irradiation include: wheat, potatoes, herbs, dried spices and processed pork. In fact, American astronauts aboard the Space Shuttle have eaten irradiated beef, pork and smoked turkey.

What Can I Do to Prevent the Problem?
Things you can do to monitor or reduce your exposure to radiation include:

• Stop smoking and/or reduce your exposure to other people’s smoke.
• Talk with your doctor and dentist about the necessity of x-rays. Follow their advice about having diagnostic x-rays.
• Test your home for radon and take action if necessary.

Where Can I Get More Information?

University of Iowa Resources

• University of Iowa Radiation Protection Office
• Cancer Information Service (1-800-237-1225)

Other Resources

• National Cancer Institute
  http://www.cancer.gov/cancer_information/

If you would like more information about radiation and cancer or telephone numbers to the above organizations, please contact the Cancer Information Service at 1-800-237-1225 or e-mail: cancer-information@uiowa.edu.

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