The current methods to remove radium from water are only about 90% effective.
Water softening uses the process of ion exchange to replace radium ions with sodium ions. Ion exchange uses particles with a charge to attract other molecules and separate and replace them in a solution. Water softening adds sodium to the drinking water and is estimated to increase sodium intake of those drinking it by 200 – 400 mg/day. Water softening is the cheapest method of water purification, but it only removes about 90% of radium contamination.
Reverse osmosis separates water from radium on a molecular level by forcing the water through a semi-permeable membrane whose pores are too small to allow radium to pass through, but will let the water through. The membrane used is very costly and the process wastes several gallons of water for every clean gallon produced.
Distillation boils water, producing steam. The steam is then condensed back into purified water. It is, however, a slow and expensive system, and distillation units generally have limited capacity, which results in restricted water flow. In addition to being inefficient, distillation allows radium to evaporate with the water, becoming radon gas. Radon gas can be carcinogenic when inhaled.
Radium is a radioactive material that emits alpha particles. It is naturally occuring in water in small amounts. When ingested in larger amounts, radium can cause a range of bone and tissue diseases.