What is Radon?
In America it is estimated that 1 in 15 homes have elevated levels of radon. In the Atlanta area, it is estimated that 1 in 6 homes have elevated levels of radon.
Radon is a colorless, odorless, tasteless, invisible radioactive gas, which comes from the natural breakdown of radium, which is a decay product of uranium. They are both common elements in the soil. Radon is considered to be the second leading cause of lung cancer deaths in America and responsible for an estimated 21,000 deaths a year. Only smoking causes more lung cancer deaths. However if you smoke and are exposed to high levels of radon your risk of lung cancer is especially high.
Radon is found to some degree all across America, and the world, and is very common in some areas. In America it is estimated that 1 in 15 homes have elevated levels of radon, but in the Atlanta area, it is estimated that 1 in 6 homes have elevated levels of radon.
Radon is measured in picocuries per liter (pCi/L) of air. A pico Curie is a measure of the amount of radioactivity of a particular substance. A liter is about equal to a quart. The average level of radon in outdoor air is about 0.4 pCi/L. The average indoor level of radon is estimated to be about 1.3 pCi/L. The EPA has established 4.0 pCi/L as a level high enough in a building that action should be taken. Since radon is a natural part of the environment there is no such thing as 0 radon. Also since it is a carcinogen no level is considered safe. However the less radon one is exposed to, the better.
Radon is a gas that comes from the soil mainly. Air pressure and temperature differences mean that a home is usually under negative pressure. Basically your house is sucking air in, some of it from the soil under the home. Normal cracks in the foundation at the floor and wall joint, at a sump pump, or drain lines can allow radon from the soil to be sucked into a home. All homes can have high levels of radon, not just homes with basements. Also tight, energy efficient homes are actually more prone to elevated levels of radon compared to older, draftier homes. Sometimes radon enters through the water supply, put usually in very low levels.
To measure the radon level in a home, G. A. Home Services uses a highly sensitive monitor that records the level of radon every hour. The minimum test period is 48 hours. At the end of the test period the results are printed from the monitor. If the average level of radon is found to be above 4.0 pCi/L then action should be taken to reduce radon levels in the home. If the average level is found to be between 2.0 and 4.0 pCi/L, the EPA recommends that homeowners consider steps to reduce radon levels. If the average reading is below 2.0 pCi/L, then additional action is generally not needed.
Homes found to have high levels of radon are generally fitted with a system of vents along with a fan connected to the vents to de pressurize the soil under the house. Essentially the radon is sucked out of the soil and out of the house to be diluted in the outside air. There are other measures that can be used to reduce radon in a home also.
To help put the effects of radon into perspective consider this from a study done in 2005. About 90 percent of people with breast cancer survive. However, over 90 percent of people with lung cancer die, mostly within 2 years of diagnosis. Lung cancer kills more Americans than breast cancer, prostate cancer, and colon cancer combined.
The risks to human health from radioactivity are well known. Over exposure to x-rays is a well known health risk, but exposure to elevated levels of radioactive radon gas in the home is much less well known by the general public.
Radioactive elements are unstable. These elements spontaneously change into another element in a decay process trying to become stable. When it changes from one element to another, a burst of radioactive energy is released. The energy can be in one of three forms - Alpha, Gamma, or Beta particles. If the element that it changed into is also unstable, it will undergo another spontaneous radioactive decay emitting more radioactive particles. An atom that begins as uranium, decays into radium, then decays into radon and then continues through a series of more decays before becoming ordinary lead, a stable element.
It is this decay process that presents the greatest health risk to humans. When a radon atom decays it becomes electrostatically charged and sticks to the linings of the lung or to dust particles suspended in the air that we breath. These decay products have relatively short half lives and emit large amounts of radiation is a short period of time.
When this decay takes place in the lungs, it is the relatively large, by subatomic standards, Alpha particles do the most damage. When a radioactive Alpha particle strikes a lung cell, one of three scenarios can occur.
1: The cell struck dies, which is not a problem since lung cells are constantly regenerating.
2: The lung cell struck does not die, but is damaged and repairs itself.
3: The cell is struck and damaged and cannot repair itself. The mutated or damaged cell proliferates and creates intermediate cells that have sustained some degree of DNA damage. This increases the pool of cells that can develop into cancer.
Not everyone exposed to high levels of radon will develop lung cancer. But the risks are greatest for those that live in homes with high levels of radon especially if they smoke. Besides quitting smoking (if you do smoke), taking steps to reduce radon in your home to levels at least below 4.0 pCi/L is the best way to reduce your risk of lung cancer for most people.
Additional information about radon can be found at the following website: www.epa.gov/radon/. If you have any questions about radon and testing your home for radon please contact me. I can be reached by email at firstname.lastname@example.org, or by calling me at 404-213-4764. Testing your home is a simple process that every homeowner should do when buying a home or in their current home if that home has not been tested..