Does Reverse Osmosis Remove Radium from Water?

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Radium is a radioactive element that often infiltrates groundwater. It poses a severe health risk for humans and, as such, is one of those contaminants people should look out for in their water supply.

As a concerned individual, you may wonder if water treatment solutions like reverse osmosis can remove radium from water.

This article will provide you with all the answers you need and more!

Key Takeaways

  • Reverse osmosis removes radium from water and it does so very effectively; up to 99.9%.

Does Reverse Osmosis Remove Radium from Water?

So, does reverse osmosis remove radium from water?

Yes, the good news is that reverse osmosis can remove radium from water. In fact, due to the nature and principle of the process, most chemical contaminants are filtered out when water passes through a reverse osmosis system.

How does it work exactly? Water flows through a reverse osmosis system under relatively high pressure. At the heart of the system lies the RO membrane. This membrane allows only few substances to diffuse through it, like water, but rejects most others, like radium.

Essentially, radium is simply too large to fit through the tiny pores (0.0001 micron in size) on the membrane’s surface. The same goes for uranium by the way.

So the radium cannot make it through the reverse osmosis membrane and, as a result, gets washed down the drain in the wastewater stream.

The purified water continues its journey through the water filter and often gets stored in a tank before ready for dispensing.

blue reverse osmosis membrane

How Effective Is Reverse Osmosis At Removing Radium?

Reverse osmosis can remove at least 95% of the radium in your water supply. Some filters can even remove up to 99.9% of radium and uranium from water.

Your best bet, however, is to look out for an NSF-58 certification when getting an RO system; it may indicate that the system is tested and can remove radium 226 and 228 isotopes, along with other elements.

To make sure, check the performance data sheet which is usually provided in the product manual. There should be a list of contaminants that the filter was third-party lab-tested to remove. Look out for a reduction rate specifically for radium.

Other Methods to Remove Radium from Water

Aside from reverse osmosis, there are a few other ways to remove radium from water.

Ion Exchange Water Softening

Ion exchange is a water treatment solution mostly employed to reduce water hardness. Well, it also works against radium!

With cation exchange technology, the water is pushed through a resin bed, and radium is deposited on the resin in exchange for other ions like sodium. Occasionally, the salt bed is regenerated or flushed to eliminate residue and reduce the risk of radium building up in the water softener.

Lime Softening

Lime softening is another treatment method that removes radium from water. As the name implies, it’s also usually used to soften water. However, it can be applied for other purposes.

Lime softening involves adding limewater (calcium hydroxide) to water, which helps to precipitate out calcium and magnesium salts. In the process, other heavy metals like radium and arsenic are removed, too.

For lime softening to be effective, the water’s pH must be up to 10.6, and there should be a significant amount of magnesium in the water.

Water Distillation

This is quite a straightforward method to remove radium. Distillation involves heating water to steam in order to separate it from impurities, and collecting the condensed steam (now purified water) afterward.

Water distillation can eliminate nearly 100% radium. The only downside is this procedure takes hours to execute.

What Is Radium, and How Does It Enter Water Supplies?

Radium is a naturally occurring radioactive element, often borne from the radioactive decay of uranium and sometimes thorium. The element was discovered in 1898 by Marie and Pierre Curie. At the time, it was used as a luminous paint for watches. Now it is used for many other purposes, including producing nuclear energy, weapons, and medicine.

Radium is commonly found in rocks and soil. Hence, both isotopes (radium 226 and radium 228) find their way into groundwater by dissolving into aquifers. The bedrocks surrounding deep confined aquifers usually contain radium which leeches into the water slowly over time.

When this water is brought to the surface, it retains the radium. And since groundwater is a major water source, radium finds its way into the water supply of many people.

Health Effects of Radium in Water

While radium may be used in some medical procedures to treat illnesses like cancer, exposure to the element is often detrimental to health. It decays to emit alpha particles which have certain harmful effects on the body. Although it may not cause immediate symptoms, accumulation over time could lead to serious issues, including:

  • Long-term health effects like cancer
  • Birth defects and mutations
  • Kidney damage
  • Anemia
  • Depression of the immune system
  • Cataract
  • Death

Generally, radium ingested from drinking water gets deposited into bones and other tissue building up over time. Then, as it radioactively decays, it emits alpha particles, eventually damaging surrounding tissues.

woman sitting in front of water glass

Safe Radium Levels?

Is there a safe level of radium in drinking water?

It’s safer not to have any radium at all in your water. However, seeing as it naturally occurs and often infiltrates groundwater, it’s almost impossible to avoid it.

Several regulations and guidelines have been implemented to ensure minimal exposure to radium. For instance:

  1. The US Environmental Protection Agency has established a maximum contaminant level of 5 pCi/L (picocuries per liter).
  2. The World Health Organization has set limits at 1 Bq/L for radium 226 and 0.1 Bq/L for radium 228 (Bq= becquerel).
  3. Health Canada has set a limit of 0.5 Bq/L for radium 226.

All public water treatment facilities are obligated to follow the EPA guidelines to ensure radium levels are reduced to a safe amount, especially in drinking water.

Is There Radium in My Water, Too?

Testing your water is the only way to know if radium is present. A professional lab test will give you a reasonable estimate of the level of radium in your water, including that of the alpha particles already emitted.

Many water filter companies offer professional testing services as well.

Another way you can guess if radium is in your water is by finding the source of your municipal water supply. If it’s from a deep municipal well, there’s most likely radium in your water.

For individuals using private wells, it’s best to get a comprehensive water test annually to monitor radium levels in your water since the EPA doesn’t regulate private wells.

If you have any thoughts about the question, does reverse osmosis remove radium, please don’t hesitate to leave a comment below!

About the Author Alexandra Uta

Alex is a content writer with an affinity for research and a methodical attention to detail. Since 2020, she has fully immersed herself into the home water treatment industry only to become an expert herself. Alex has been using water filters and similar products for years which has gained her lots of hands-on experience.
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