Radon, a heavy gas that can cause lung cancer, develops naturally in the Earth's soil, the result of billions of years of radioactive decomposition. It presents a danger when it seeps into our homes and water supplies. It has been developing since the planet was formed, so there's not much we can do to stop it. We can, however, take steps to keep dangerous levels of it out of our homes.
Identification
Radon is a heavy, colorless, odorless gas. It is the 86th element on the periodic table of elements and is a member of the noble gas family, which also includes helium and xenon. Noble gases are so named because they rarely combine with other elements to form compounds. Radon also is radioactive, meaning it constantly releases energy as it converts into another element. It appears naturally in the Earth's atmosphere in very small amounts.
Formation
Radon forms as part of the breakdown of another radioactive element, uranium. As uranium decays, it breaks down into a chain of solid radioactive elements, including thorium, protactinium and radium. Radium then decays into radon, which as a gas can seep up through the soil into homes, water sources and the atmosphere. Radon then breaks down into other radioactive elements, eventually becoming a stable form of lead. Uranium appears in virtually every type of soil and takes billions of years to decay, so radon can and will continue to appear almost anywhere on Earth.
Significance
The U.S. National Cancer Institute lists radon as the second leading cause of lung cancer in the United States, causing as many as 22,000 lung cancer deaths each year. Because of the way radon develops, it can seep into your home without you knowing it. Breathing radon causes damage to your lungs as it releases radiation inside of them. Radon breaks down quickly--it's half-life, the amount of time it takes for half of the quantity of a radioactive element to decay into another element, is just under four days--but the radium that emits it has a half-life of more than 1,600 years, so more radon will constantly seep into your home.
Prevention/Solution
You can test your home's radon levels with a do-it-yourself kit or by hiring a qualified tester. A number of factors can affect how much radon is getting in--barometric pressure or rainfall, for example--so you should test over several days. Don't rely on your neighbor's test results. The soil under your home might have a higher uranium composition, or you might have more entry points for radon, so testing your own home is the only way to determine your levels.If you have high levels of radon in your home, you can reduce them by sealing cracks in the foundation and walls and venting the radon out of your home. This can cost between $800 and $2,500, according to the National Cancer Institute.
Misconceptions
Knowing how radon develops dispels some of the myths that surround it. It is not limited to any certain geography, nor is potentially harmful radon exposure limited to any specific type of home. Also, you should test your air for radon before you test your water, according to the U.S. Environmental Protection Agency. If radon is infiltrating your water supply, which in most cases happens in homes with private wells, it also will be present in your air.
