How Reverse Osmosis Removes Uranium from Drinking Water

If you are concerned about the presence of uranium in your drinking water, you may be wondering if reverse osmosis can remove it.

Reverse osmosis can remove uranium from drinking water very effectively. Reverse osmosis systems have been shown to remove 90 to 99% of uranium in water. RO can be used to achieve similar results for alpha particle activity, total beta activity, and photon emitter activity.

In this blog post, we will discuss how reverse osmosis works and how it can be used to remove uranium from drinking water. We will also provide information on the cost of installing a reverse osmosis system in your home.

About Uraniumradionuclides in water

Uranium (U) is a radioactive element found in nature that doesn’t have any stable isotopes. There are three major isotopes of naturally occurring uranium:

  1. uranium-238 (U-238) – Also known as depleted uranium, it is the most abundant isotope (99.3%)
  2. uranium-235 (U-235) – This is the only naturally occurring isotope capable of sustaining a nuclear fission reaction (0.72%)
  3. uranium-234 (U-234) – It is used in the making of nuclear weapons and nuclear fuels (0.0050%)

Uranium is found in many forms of rocks and is mined in many countries around the world. The United States has large deposits of uranium in Colorado, Wyoming, and Utah. This element is mined in many countries around the world.

Not all rocks contain uranium, but there are many places where it is in the bedrock. Additional elements frequently found alongside uranium are radium and radon.

How does uranium get in my waterUranium in Drinking Water Map of US

Groundwater in contact with rocks containing uranium can become contaminated with uranium. The amount of uranium in bedrock and well water will vary greatly from place to place. Deeper, bedrock wells are especially susceptible to contamination.

Uranium seeps into well water via uranium-rich rock. Uranium levels in bedrock and well water can greatly differ depending on location. The only way to know if uranium is in your well water is to test it.

The chemical properties of uranium in drinking water are of greater concern than its radioactivity. Studies show that drinking water with elevated levels of uranium can affect the kidneys over time. Bathing and showering with water that contains uranium is not a health concern unless uranium levels are extremely high.

Health concerns with uranium

The greatest health concern associated with uranium is its radioactivity.

Studies have also shown that uranium in drinking water can lead to an increased risk of kidney damage. The majority of uranium ingested is excreted from the body. However, a tiny amount is absorbed and circulated throughout the bloodstream.

Neither the International Agency for Research on Cancer nor the U.S. National Toxicology Program have not assigned a carcinogenicity rating for uranium. The U.S. EPA withdrew its carcinogenicity classification for uranium.

Uranium is also a toxic chemical. Ingestion can cause kidney damage much sooner than its radioactive properties would cause cancers of the bone or liver.

Drinking water standard for uranium

The EPA established a maximum contaminant level (MCL) for uranium of 30 micrograms per liter (µg/L).

The current EPA standards for radionuclides in drinking water are:

  • combined radium 226/228 of 5 pCi/L
  • A gross alpha standard for all alphas of 15 pCi/L (not including radon and uranium)
  • A combined standard of 4 mrem/year for beta emitters.

Test Your Drinking Water for Uranium

Tap Score Full Radiation Water Test
Tap Score has a simple to use test that screens your drinking water for uranium.

If you are a homeowner looking to test your water for radiation, Tap Score’s full radiation test is the perfect solution for you. This package includes all of the materials necessary to collect and submit a sample for certified laboratory testing. You will receive detailed analysis of Alpha Radiation and Beta Radiation from any source – including radium, uranium, cesium, and strontium.

While each of these sources can be tested individually, this broad radiological screen is recommended unless you already suspect a specific problem.

Order your Tap Score full radiation test today.

Reverse Osmosisreverse osmosis filter system

Reverse osmosis (RO) is a water treatment technology that removes a wide range of contaminants from water. It is effective at reducing the concentration of many impurities such as lead, PFAS, and heavy metals.

How RO works

Reverse osmosis works by passing water through a semi-permeable membrane. This membrane allows water molecules to pass through but not larger particles such as dissolved solids.

The water is forced through the membrane by applying pressure, and the impurities are filtered out. The purified water is collected on the other side of the membrane, while the contaminants are retained in a concentrated brine. This brine waste is then flushed down the drain.

Reverse osmosis systems can be used to treat both municipal water supplies and private wells. This treatment technology is effective at removing a wide range of contaminants, including salt, bacteria, viruses, pesticides, and many more.

RO system componentsRO Sediment Pre-Filter

Residential reverse osmosis systems typically consist of three treatment processes:

  1. pretreatment
  2. reverse osmosis membrane
  3. post-filter

The pretreatment module usually consists of a sediment filter and an activated carbon filter. These are provided to protect the membrane from fouling and damage caused by chlorine. The sediment filter’s primary function is to remove suspended solids such as dirt and rust. The activated carbon filter works to eliminate chlorine and other chemicals that might damage the RO membrane.

The reverse osmosis membrane is the workhorse of the system. Most membranes are a thin film composite (TFC) made of several layers of material, including a semi-permeable membrane.

The final stage of filtration, after the filter, is the post-filter. It removes any remaining pollutants from the water. It is usually a second carbon filter

How Well Does Reverse Osmosis Treat Uranium

Reverse osmosis is very effective at treating water contaminated with uranium. Most RO filters can remove 95% or more of this radionuclide. Some high-quality reverse osmosis filters can remove 99.9% of uranium in drinking water.

How much uranium can reverse osmosis remove

Reverse osmosis is an effective way to remove uranium from your drinking water.

No reverse osmosis systems have NSF certification to reduce uranium. However, many reverse osmosis systems are certified to reduce radium 226/228, a by-product of decaying uranium.

Uranium and radium have similar properties (solubility and atomic size), so you can use radium as a surrogate for uranium when selecting a reverse osmosis system. RO systems certified for reduction of radium may also be effective at reducing uranium.

The following reverse osmosis systems are certified by NSF.

Reverse Osmosis Filters Certified to Remove Uranium 226 and Uranium 228
Brand Model Number Flow Rate (gpm)
A.O. Smith Water Treatment AORO-50 11
Aqua Systems AQPC-35 11
Aqua Systems AQPC-435 11
Aquasana, Inc. OptimH2O™ AQ-RO-3 13.32
Aquion, Inc. Rainsoft Ultrefiner II-FMV-BNFP 24.22
Atlantic Filter Corporation HR-35-TFC-4W 11
Clover Co., Ltd. AQVR5 23.39
Clover Co., Ltd. CLVR5 23.39
EcoWater Systems LLC ERO-175 18.46
EcoWater Systems LLC ERO-385 15.75
EcoWater Systems LLC ERO-385-BN 15.75
Everpure LLC Conserv 75E 50.51
Everpure LLC Conserv 75S 50.51
Everpure LLC LVRO-75HE 14.66
Franklin Water Treatment, LLC Puronics Micromax 6000 TFC 8.28
Franklin Water Treatment, LLC Puronics Micromax 6500 TFC 8.28
GE Appliances, a Haier Company GNRQ18NBN 14.76
GE Appliances, a Haier Company GXRQ18NBN 14.76
Lancaster Water Treatment Brita Pro BPLRO-35 11
Lancaster Water Treatment CRO-350 11
Lancaster Water Treatment PRO-50 11

Challenges with uranium and RO

One significant issue with reverse osmosis is the brine that it creates. Brine is the concentrated waste left behind after the contaminates have been filtered out of the water. This wastewater contains all of the uranium that was removed from your drinking water. Often the concentrations are extremely high.

Disposing of concentrated uranium brine into your septic system can contaminate groundwater. To avoid discharging this hazardous compound into the environment, the brine must be properly disposed of. Disposing of a radioactive waste can be costly and may require special permits.

Factors to Consider with Reverse Osmosis

If you’re concerned about the quality of your drinking water, a reverse osmosis filter may be a good option for you. RO filters are able to remove a variety of contaminants from your water, including lead, mercury, and chlorine. However, there are a few factors you should consider.

Installation cost of reverse osmosis

Depending on your home’s plumbing, installing an RO system can be relatively simple or quite complex. If your home has a standard under-sink configuration, you can likely install the filter yourself. However, if your home has multiple faucets or you need to drill new holes for the filter, it’s best to hire a professional.

A whole-house RO system can be expensive to install, especially if you have to modify your home’s plumbing. An under-sink unit, on the other hand, can often be installed by a good do-it-yourselfer for a reasonable cost. Each home is unique, so you’ll have to determine which system is right for you.


RO filters have sediment filters and activated carbon filters that have to be replaced. A sediment filter will usually last for about six months before it needs to be replaced. Carbon filters have to be replaced every 3 to 6 months, depending on how much water you use and the amount of chlorine in your water.

The cost of replacement filters can vary, but you can expect to spend around $60 to as much as $200 per year on them. Whole house filters are 3 to 4 times as much as under-sink filters.

While this may seem like a lot, it’s important to remember that RO filters can remove a variety of contaminants from your water, making it safer and healthier to drink.

Whole-house versus under-sinkWhole House RO System Diagram

Another thing to consider is how much water you’ll need to filter. RO filters are typically sized according to the number of gallons they can process per day. If you have a large family or use a lot of water for cooking and bathing, you may need a larger filter.

Reverse osmosis systems are available in a wide range of sizes, from small countertop units to large industrial systems. They can be used for point-of-use (POU) applications, such as filtering water for a kitchen sink, or point-of-entry (POE) applications, such as filtering all the water coming into your home.

Deciding which type of RO system is right for you depends on a number of factors, including your budget, the size of your home, and your water quality. Read my article on under-sink RO systems and whole-house RO systems for a detailed explanation.

NSF certification

Reverse osmosis filter manufacturers often make claims about how well their units remove contaminants. The best way to be certain of their claims is to look for units that have been certified by NSF International.

NSF is an independent organization that tests and certifies products to ensure they meet strict standards for quality and safety. If a product has been certified by NSF, you can be confident it will perform as advertised.

The applicable standard for point-of-use reverse osmosis systems is NSF/ANSI 58. It covers the following parameters:

  • Materials of construction and leaching of harmful substances
  • Mechanical integrity
  • Removal of total dissolved solids (TDS)
  • Efficiency rating
  • Recovery rating
  • Contaminant concentration reduction

Treatment Methods that Remove Uranium

In addition to reverse osmosis filtration, there are other treatment methods that can be used to remove uranium from drinking water, including:

  1. Ion exchange
  2. Distillation

Cationic ion exchange media do a nice job of removing radium and uranium from drinking water. One benefit of ion exchange is that it does not remove beneficial minerals like calcium or magnesium.

Water is pumped through a vessel filled with the resin. Radium is adsorbed onto the media and treated water is discharged. Eventually, the ion exchange media becomes saturated with radium, and it can no longer remove any more of the contaminant.

Once the resin is “spent”, it can be regenerated by flushing the bed with a concentrated solution of salt. This releases the radium, which is then flushed out of the system. The media can be reused after regeneration.

Ion exchange for removal of uranium

You can remove uranium from water using ion exchange resin. The resin will remove the uranium, but it does remove minerals like calcium and magnesium.

The ion exchange resin is placed in a pressure vessel. Water is pumped through the vessel, and the uranium is adsorbed onto the resin. The ion exchange medium eventually becomes saturated with uranium, and it can no longer remove any more of the contaminant.

To regenerate the resin, you will need to flush it with a concentrated solution of salt. This will release the uranium, which can then be flushed out of the system. The media can be reused after regeneration.

Distillation to remove uranium

Another treatment method that can remove uranium from drinking water is distillation. Distillation involves boiling water and then condensing the steam back into water. This leaves behind impurities, including uranium.

Distillation is an effective way to remove uranium, but it does have some drawbacks. It’s energy intensive, so it can be expensive to operate. Additionally, it removes all minerals from water, including calcium and magnesium.

Under-sink reverse osmosis filter

Here is the under-sink reverse osmosis filter I installed in my kitchen. You may interested in something similar for your home.

Check Pricing on Amazon


Does activated carbon remove uranium

Carbon filters are ineffective at removing uranium from drinking water. The following types of carbon filters are not effective at removing radium:

  • pitcher filters (Brita, Pur, ZeroWater)
  • refrigerator filters
  • faucet filters

Does boiling water remove uranium

Boiling water does not remove uranium from drinking water. Boiling should not be used to treat uranium contaminated water because evaporation of water increases the concentration of uranium.

Does a water softener remove uranium

Water softeners do not remove uranium from drinking water. Water softeners remove hardness minerals like calcium and magnesium from the water. They do not remove radium.


Reverse osmosis is an effective way to remove uranium from drinking water. It’s a physical process that uses pressure to force water through a semipermeable membrane, leaving contaminants behind. Reverse osmosis removes up to 99% of uranium from water.

One consideration with reverse osmosis is the concentrated radioactive waste that must be managed. The brine solution that is flushed from the system during regeneration can contain high concentrations of uranium. This waste must be properly disposed of to protect the environment and public health.

There are other treatment methods that can be used to remove uranium from water, including ion exchange and distillation. However, these methods have drawbacks. Ion exchange removes beneficial minerals like calcium and magnesium from water. Distillation is energy intensive, and it removes all minerals from water.

If you have uranium in your drinking water, reverse osmosis is the best way to remove it.

Boch Richard

Richard Boch is a chemical engineer responsible for designing water filtration systems for industrial and residential customers. He has more than 20 years of experience with ion exchange, activated carbon, and reverse osmosis. Richard's expertise has made him a go-to source for municipalities and businesses looking to improve their water quality. When he's not working, Richard enjoys spending time with his wife and two young children.

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