Does Reverse Osmosis Remove Copper

Does Reverse Osmosis Remove Copper

Are you a homeowner with high levels of copper in your drinking water. If so, you may be wondering if reverse osmosis can remove copper.

Copper is a common mineral found in drinking water, and while it is essential for human health in small doses, too much can be harmful. Reverse osmosis systems can effectively remove copper from drinking water. A relatively inexpensive under-sink RO filter can remove more than 95% of copper. A high-quality reverse osmosis filter that is properly maintained can remove 99% or more of copper.

Reverse osmosis systems are very effective at removing copper from drinking water. If you have high levels of copper in your water, or just want to learn more about RO systems and how well they treat copper, continue reading.

About Copper

Copper is found throughout our homes, especially within the plumbing system where it can leach into drinking water. While copper is an essential mineral for human health, too much can be a concern for homeowners.

copper pipe corrosionCopper finds its way into our drinking water from the following sources:

  • Corrosion of copper plumbing materials
  • Industrial pollution
  • Copper salts used for algae control

What is copper

Copper is a naturally occurring metal in earth’s crust, with many uses including electrical wiring and plumbing. Copper is also essential to human health, aiding in energy production, the nervous system, and a healthy immune system.

Copper is an essential mineral to the human body. It plays a role in energy production, the nervous system, and a healthy immune system. Copper can be found in many food items such as dark leafy greens, beans, nuts, seeds, and shellfish.

Health concerns with copper

If you’re concerned about the levels of copper in your water, it’s important to take action to remove it. Excessive levels of copper can have harmful health effects including:

  • stomach irritation
  • nausea
  • vomiting
  • damage to your liver and kidneys

Copper is especially dangerous to the health of toddlers and infants. While copper toxicity is rare in the United States, it’s best to be safe and take action if you’re worried about the quality of your drinking water.

Other issues with copper

In addition to health issues, copper also causes other problems. It can stain laundry and discolor plumbing fixtures. At very high concentrations, it can give water an unpleasant taste.

Drinking water standard for copper

EPA has set standards for copper levels in drinking water, and as long as your water falls within those guidelines, you don’t have to worry.

The Maximum Contaminant Level Goal (MCLG) for copper is 1.3 mg/L (or ppm). This is the health-based goal at which no known or expected detrimental effects on human health have been demonstrated and for which a sufficient safety margin exists.

Copper is also an aesthetic contaminant (metallic taste) under the USEPA’s standards, with a Secondary Maximum Contaminant Level of 1.0 ppm.

Reverse Osmosis

Reverse osmosis is a widely used treatment method that reliably removes a wide range of contaminants from drinking water. It is effective at reducing the concentration of impurities such as lead, PFAS, and heavy metals

How RO worksHow Reverse Osmosis Works

Reverse osmosis systems use a semipermeable membrane to remove impurities from water. The membrane allows water to flow through while trapping dissolved solids and other contaminants. The system applies pressure to the water, forcing it through the membrane and removing any impurities.

The membrane is constructed of a semi-permeable polymer that is spirally wrapped around a central tube. The water is forced through the membrane, and the impurities are filtered out. The clean water is then 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. They are effective at removing a wide range of contaminants, including lead, bacteria, viruses, pesticides, and more.

RO system components

Reverse osmosis systems typically consist of three modules:

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

RO Sediment Pre-FilterRO Activated Carbon Filter

Pretreatment protects the membrane from fouling and damage caused by chlorine. It usually consists of a sediment filter and an activated carbon filter. The sediment filter removes particles such as dirt and rust, while the activated carbon filter removes chlorine and other chemicals.

The reverse osmosis membrane is the heart of the system. It’s a thin film composite (TFC) that remove contaminants from water. The TFC is made of several layers of material, including a semi-permeable membrane.

The post-filter is a final stage of filtration that removes any remaining impurities from the water. This is typically a second carbon filter that ensures the water is safe to drink and tastes great.

Some RO systems include a water storage tank, which stores the clean water until you’re ready to use it. This is desirable because the flow rate through the filter is slow. Having a storage tank ensures you can fill a glass or a cooking pot quickly with clean water without having to wait.

How Well Does Reverse Osmosis Treat Copper

Reverse osmosis filters are very effective at removing total dissolved solids (TDS) from water. TDS is a measure of all inorganic and organic substances dissolved in water – and this includes metals like copper.

RO filtration is very effective at removing copper from water. Data from hundreds of operating reverse osmosis systems indicate that copper concentrations are reduced by 95 to 99.99%.

How much copper can reverse osmosis remove

The CDC rates reverse osmosis as highly effective at removing copper from water. This means that RO can consistently remove at least 95% of the copper.

Theoretically, the copper concentration in your water could be as high as 26 ppm – a very high level – and an RO filter could reduce the copper to 1.3 ppm. This is the MCL established by the EPA.

As you can see from this example, reverse osmosis can effectively remove copper from your drinking water under virtually any scenario.

Challenges with copper and RO

Reverse osmosis can readily remove copper from water. One thing you’ll want to check is why the copper levels are high in your drinking water. One source of elevated copper is corrosion of copper pipes. If this is the case in your home, you’ll want to have your plumbing inspected. It may be necessary to replace the copper pipes or address the underlying cause of the corrosion.

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.

Maintenance cost

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-sink units

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 certificationNSF certification for reverse osmosis filters

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


Does activated carbon remove copper?

Activated carbon does not remove copper. Copper is an ion when it is dissolved in water. Carbon does not remove ions.

Does boiling water remove copper?

Boiling water does not remove copper. In fact, boiling water contaminated with copper only makes it worse because as the water evaporates, the copper concentration increases.

Does a water softener remove copper?

Water softeners remove hardness – calcium and magnesium, but they do not remove copper from water.


If you’re a homeowner concerned about copper in your drinking water, you may want to consider investing in a reverse osmosis system. RO systems are available in both whole-house and under-sink models, and they can remove a variety of contaminants from your water, including copper.

Look for units that have been certified by NSF to be sure they will perform as advertised. Be sure to change the filters according to the manufacturer’s recommendations to keep your water safe and healthy.

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. You can also follow him on LinkedIn, Twitter and Facebook.

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