- What is radium?
- How might I be exposed to radium?
- How would I know if my drinking water contains radium?
- What is the drinking water standard for radium?
- What are the health concerns relating to radium in drinking water?
- Can radium be removed from drinking water?
- Where can I get more information?
What is radium?
Radium is a metal that is found in nature. It is radioactive and can exist in several forms (called isotopes). Radium can be found at varying levels throughout Vermont and the entire earth—in soil, water, rocks, plants and food.
How might I be exposed to radium?
We are all exposed to very low levels of radium every day.
You also can be exposed if your drinking water comes from a well that contains radium. Although this is relatively uncommon, it can occur if radium is present in the rock where the well is drilled. The radium dissolves from the rock and enters the well water.
How would I know if my drinking water contains radium?
Community public water systems test their well water for radium. If the amount of radium found in the drinking water sample exceeds drinking water standards, the water system is notified and a plan is developed to reduce levels.
Private well owners can have their water tested for radium at a laboratory certified to test for radium by the Health Department's Drinking Water Certification Program. There are fees for testing services.
What is the drinking water standard for radium?
Radium is measured in picocuries per liter (pCi/l) of water. The U.S. Environmental Protection Agency has set 5 pCi/l as the maximum contaminant level for drinking water. It is based on the combined amount of the two isotopes, Ra-226 and Ra-228, found in the water sample.
What are the health concerns relating to radium in drinking water?
There are no immediate health risks or symptoms from drinking water that contains radium. However, it may cause health problems over time. Radium is radioactive and decays very slowly. During this process, radiation is released. The health effects of exposure to radiation vary according to how long a person is exposed and how much radium or radiation a person is exposed to. Over decades, exposure to radium can increase the risk of bone cancer.
Can radium be removed from drinking water?
Yes. A water softener (also called a cation exchange unit) is able to remove nearly all radium found in drinking water. In the softener, radium is exchanged for sodium or potassium. When the softener is cleaned, the radium is flushed away with the wastewater. With this type of treatment, the sodium or potassium remains in the drinking water.
Another type of treatment called reverse osmosis has also been shown to remove most radium from drinking water. In this process, water is forced under pressure through a membrane leaving the radium behind. The radium is then flushed away. This process is slow and more suitable for a household well than for a public water system. With either type of treatment, proper operation and maintenance are essential.
If radium contamination is discovered, some public water systems choose to abandon the well and connect to a neighboring supply rather than treat the drinking water. Another option for the water system is to blend their well water with another water supply that meets the standards to produce reduced-radium water.