Water and Radon
If you have 4 pCi/L or higher radon concentration in your home, you may want to test your water if it comes from a well. Radon may enter your home largely through soil and water. Most radon enters your home through the soil. Radon in water may be transferred to your air through showering, cooking, and other household water uses. According to the National Academy of Science (NAS) and the EPA, 10,000 pCi/L in drinking water raises indoor air radon by 1 pCi/L.
Radon in surface water or radon in ground water comes from the soil around the surface water or the well or aquifer containing radon or the elements it results from respectively. Water coming to you from an underground well or aquifer whether your own or a public source could have radon in it. If your water comes from surface water, radon in water is not usually a problem. It is not very soluble in water and it usually escapes into the air way before it gets to you. If your drinking water comes from a private well, you are responsible for testing your water for contaminants. EPA rules do not apply to private wells (although some state rules do), but EPA recommends that well owners have their water tested annually. The main risks from radon in well water are stomach cancer and lung cancer from swallowing radon water and inhaling radon that escapes from dishwashers, showers, and washing machines respectively.According to the BEIR REPORT (put out by the National Academy of Science) the estimated risk posed by radon from drinking water is small, but is larger than the risk from other regulated drinking water contaminants. The Report estimates that about 168 to 183 deaths occur each year through inhalation and ingestion as a result from exposure to radon drinking water.
According to the EPA, some people who drink water containing radium -226 or -228 in excess of the 5 pCi/L (1976) over many years may have an increased risk of getting cancer. The National Academy of Science concluded that no current evidence exists that shows a threshold of exposure below which radon levels are harmless.
When testing well water for radon, there are two types of treatments that can be done. If you find radon in the water you can use one of these treatments to take radon from your water supply. These are referred to as point of entry and point of use. The point-of-entry treatment is the most effective because it removes radon from the water before it enters your home. Of the two types of point of entry processes, one involves using activated charcoal while the other uses aeration techniques. Point-of-use radon water treatment devices contain activated charcoal to remove radon in drinking water at the tap. If your tap water is the only water treated, radon may still be released into the air from other uses of water in the home.
Click here for... EPA Fact Sheet on Radon in Drinking Water: Questions and answers
