Some potential threats to good health are more obvious than others. Smoking, overeating, and other lifestyle issues may be readily apparent to us all. However, one subtle and silent hazard is gaining more attention by the day: radon.
Tasteless, Odorless, Colorless-Dangerous
By Mike Haskew
Radon is a naturally occurring gas that is a byproduct of the decay of uranium, an element present in rock and soil. As uranium decays, radon – a tasteless, odorless and colorless gas – seeps into the atmosphere through cracks in the rock, permeable soil, and groundwater. In turn, radon continues to break down into a series of “daughter” products including lead, astatine, bismuth and polonium. Exposure to concentrations of radon gas in enclosed spaces heightens the risk of lung cancer, and debate continues to surround this issue.
Although radon is naturally occurring in the environment and all living creatures come into contact with it, a particular concern for people is the potential for its concentrated presence in homes and other buildings. Potentially seeping into living spaces, radon may enter buildings through cracks in foundations, construction joints, or even through the local water supply. Areas in which the potential for high levels of radon are greatest include:
• those where uranium-rich rock is known to be present
• buildings with rooms such as basements that are partially or completely constructed in-ground
• building sites on hills or slopes
• locations where the soil drains rapidly or is dry for extended periods
• areas of thin soil with bedrock lying exposed or near the surface
• locations where underlying rock is fractured
• where limestone caverns are known to be located, and
• areas where high levels of radon have already been reported.
Research is ongoing on the potential health hazards posed by radon, and statistics suggest that exposure to this invisible and silent gas may account for up to 12 percent of all diagnosed cases of lung cancer in the United States. In other words, radon may contribute to as many as 15,000 to 22,000 of the 158,000 annual deaths occurring in the U.S. due to lung cancer. In 2005, the U.S. Surgeon General issued a health advisory, suggesting that testing homes and buildings for exceptionally high levels of radon should take place across the country.
Lung cancer caused by radon is virtually identical to the disease that may have been contracted from other causes. “The different types of lung cancer are treated in the same fashion, regardless of the potential cause of the cancer,” explains Dr. Stephen Golder, medical director of the Sarah Cannon Cancer Center at Parkridge. “The exact cause is usually impossible to determine in individual cases, the exception being mesothelioma and asbestosis exposure.”
Dr. Hosam Naguib, a medical oncologist with NW Georgia Hematology and Oncology, P.C. and chairman of the Executive Cancer Committee of Hamilton Regional Cancer Institute in Dalton, agrees. “Lung cancer from radon exposure is not different biologically from lung cancer due to another cause,” he comments. “Smoking and radon exposure can separately increase the risk of lung cancer. However, exposure to both greatly enhances that risk. Exposure to radon within the home may play a role in the development of lung cancer in patients who never smoked.”
While some conjecture still surrounds the research into radon and lung cancer in non-smokers, the Environmental Protection Agency has concluded that radon exposure is the leading cause of lung cancer among individuals who do not smoke. “We know that radon is a carcinogen,” remarks Tom Kelly, former director of the EPA Indoor Environments Division, citing a pair of studies conducted in the U.S. and Europe. “This research confirms that breathing low levels of radon can lead to lung cancer.”
Some studies have indicated that exposure to radon within the home is a primary contributor to the incidence of lung cancer. Statistically, an individual who smokes and is exposed to low levels of radon over time has a 20 in 1,000 chance of dying of lung cancer, while those who have never smoked but are exposed to the same level of radon experience a two in 1,000 likelihood of dying of lung cancer. Certain occupations have also been linked to higher incidences of radon exposure and, therefore, lung cancer. Uranium miners, logically, are among these.
The fact that radon has been detected in all 95 counties in the state of Tennessee is particularly noteworthy, and action may be taken to decrease radon levels in homes and buildings. Inexpensive tests are available, and the Tennessee Department of Environment and Conservation provides an indoor radon program that includes test kits, technical information, and data that is useful for homeowners, contractors, inspectors and real estate sales professionals. Testing during cold weather months from October to March results in the most accurate readings since homes are most often closed to the outside and air circulation is at its lowest.
Approximately six percent of the homes tested across the country are found to have elevated levels of radon present, while in Tennessee an average of 16 percent has been noted, and in some counties the number is between 33 and 75 percent. Should elevated radon levels be detected, homeowners may take corrective actions such as sealing cracks, installing a new water heater, or painting. These steps are most effective when performed by a qualified contractor.
Dr. Golder offers advice to those concerned with exposure to radon. He says, “Avoid cigarette smoking and living in a house that is closed up and does not have sufficient ventilation. Have your home tested if you are concerned about possible radon levels and – avoid being a uranium miner.”
In assessing the health risks associated with radon exposure, Dr. Naguib recommends contacting a physician and gathering information. “If someone suspects they have become ill due to radon exposure, they may contact the American Lung Association’s local chapter,” he advises. “They offer information on radon exposure, testing for radon, and provide testing kits for a nominal fee.”
Other resources include the National Radon Hotline at (800) SOS-RADON and the Tennessee Radon Hotline at (800) 232-1139. Tennesseans may also take advantage of free radon testing kits through their county’s ground water protection office.