Radium
A question of local geology
Radium is a naturally occurring radioactive element present in varying amounts in rocks and soils. The most common groundwater isotopes are radium-226 and radium-228, and the level of concern depends heavily on local geology — deep bedrock aquifers used for drinking water sometimes exceed regulatory limits.
Two parents, one element
Surface water and shallow-aquifer well water typically do not present radium issues. Radium-226 results from the radioactive decay of uranium (emitting alpha particles), while radium-228 results from the decay of thorium (emitting beta particles); radioactive contaminants of this kind are often called radiochemicals or radionuclides.
Why alpha particles matter
While most ingested radium passes through the body, a portion is absorbed and deposited in bone, where its behavior drives the associated health concerns. Radium emits alpha particles and gamma rays, and decays further into radon gas — the production of high-energy alpha particles is the primary health concern for radium and other radionuclides.
Radium’s decay into radon presents a further contaminant concern, both in water and in air. Exposure to alpha radiation can damage surrounding cells and increase the risk of cancer, kidney damage, and birth defects. Radium-226 and radium-228 share the same physical and chemical properties, so treatment removal efficiency is the same for both.
Judged on the annual average
The EPA regulates radium under the National Primary Drinking Water Standards for radionuclides, with a combined MCL of 5 pCi/L for radium-226 and radium-228, and a separate MCL of 15 pCi/L for gross alpha activity. Because radionuclide levels can vary, compliance is assessed using a running annual average of quarterly readings, so a single elevated quarterly reading may not indicate a problem if the annual average remains within limits.
Public Health Concern
Radium cannot be seen, smelled, or tasted in drinking water. Only a small portion of ingested radium is absorbed in the digestive tract, with the majority passing through the body unchanged — but absorbed radium is deposited in bone, given its chemical similarity to calcium.
Deposited radium emits alpha particles that can damage surrounding tissue, potentially causing immune system suppression, anemia, cataracts, and fractured teeth. At high exposure levels, radium can cause bone, stomach, lung, and other cancers, and its decay into radon adds a further health concern in both water and air.
Pilot study first
The optimal radium removal technology depends on water properties — pH, for instance, affects radium’s chemical bonding and therefore removal efficiency across different treatment processes. Because analyzing water test data alone rarely identifies the best process, a pilot study is the recommended path forward.
Radon and radium in a single vessel
WETS brings many years of experience treating radionuclides such as radium. Our pilot studies for radium removal typically evaluate ion exchange and filtration approaches such as greensand filtration, coagulation/dual media filtration, and hydrous manganese oxidation filtration. Because radon gas — the immediate decay product of radium — is often a concern where radium is present, our proprietary aeration/filtration unit can remove both radon (through aeration) and radium (through filtration) in a single vessel, reducing treatment cost and equipment footprint.
Solutions to Your Water Treatment Needs
Whether you want a new water treatment system installed, need your current one inspected and repaired, or just want a free quote, contact the WETS LLC. With years of experience in the industry, our skilled team members are trained and knowledgeable with a variety of leading water equipment and products. Our certified water purification experts are here to help.
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