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Health Risks of Radon Gas

A radioactive gas given off by soils in confined spaces such as residential buildings and underground mines is known as radon. When uranium decays naturally into radium, this noble gas is a byproduct and makes up a significant source of ionizing radiation. Although radon gas has a half-life of about four days, it poses considerable risks to human health.

  1. Lung Cancer

    • After smoking, radon is the next leading cause of lung cancer and accounts for about 21,000 deaths annually in the U.S., according to the Environmental Protection Agency. Studies on lung cancer and radon conducted in Asia, Europe and North America reveal that an average range of 3 percent to 14 percent of lung cancers are due to radon exposure, as reported by the World Health Organization. In addition, the risk of lung cancer rises proportionately to the level of exposure rather than greater concentration. Due to the synergistic effect of smoking and radon, the majority of radon-related lung cancers arise among smokers.

      If breathing in radon, an individual's bronchial epithelium, airways and skin typically receive the greatest dose of ionizing radiation. The bone marrow and kidney may be exposed to lower doses. If drinking water with dissolved radon, an individual's stomach is also vulnerable to exposure.

    Stomach Cancer

    • Although radon in household drinking water raises an individual's overall exposure, the risk of contracting stomach cancer is insignificant, according to a study by the National Research Council. Approximately 20 of 13,000 deaths due to stomach cancer may be attributable to waterborne radon. The Environmental Protection Agency also conducted its own study, estimating that about 100 liver, colon and stomach cancer deaths result from drinking radon in water.

      Although a rare situation, radon can penetrate the stomach and injure cells. If radon passes into the bloodstream via the stomach or intestine, it is usually discharged from the body through the lungs and therefore does not affect other organs.

    Acute Lymphoblastic Leukemia

    • Research from Denmark has indicated that children who reside in residences with high levels of radon may be more at risk for acute lymphoblastic leukemia, a cancer in which white blood cells proliferate in the bone marrow. Dr. Ole Raaschou-Nielson of the Institute for Cancer Epidemiology in Copenhagen studied the lifelong radon exposures of 2,400 children with cancer and approximately 6,700 healthy children. Children who were 15 or younger and exposed to middling levels of radon showed a 21 percent greater risk of developing acute lymphoblastic leukemia than children exposed to lower radon levels, as reported by MedicExchange.

      However, Rasschou-Nielson and his colleagues have been unable to explain the biological link between radon and ALL. "The etiology of childhood cancer has remained elusive, especially with regard to possible environmental influences," said Dr. Andrew F. Olshan of the University of North Carolina in response to the study.

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