What Does Reverse Osmosis Remove from Water?

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Reverse Osmosis removes impurities from water. It also makes drinking water safe to drink again. But how exactly does it work? And why do we even care?

Well, reverse osmosis works just as well as any other filtration system. In fact, it’s far superior because it doesn’t require electricity or chemicals.

But why should you care? Because reverse osmosis systems are expensive. They cost thousands of dollars. But with a little research, you can find a great deal on a quality reverse osmosis system.

I’ll explain everything you need to know about reverse osmosis systems, including what reverse osmosis removes from the water. is it safe, and what are the advantages of a reverse osmosis filter?

what does reverse osmosis remove from water

What is Reverse Osmosis?

Reverse osmosis is a process that uses pressure to force water molecules through a membrane filter. Water passes through the membrane, leaving behind contaminants such as salt, minerals, and bacteria.

The result is pure drinking water. Reverse osmosis systems are commonly used in homes and businesses to purify tap water. However, they can also be used to treat wastewater.

Reverse osmosis is a great option for treating wastewater because it doesn’t require chemicals or electricity. It’s also cost-efficient since it requires little maintenance.

What Toxins Does Reverse Osmosis Remove?

Reverse osmosis systems will remove common chemical contaminants from your drinking water.


A reverse osmosis system removes nearly 80% to 90%, depending on how well it was built, of fluoride from your drinking water, so it’s ideal for those who specifically seek to remove fluoride from their water supply.

However, it can also remove smoke residue, including nicotine, from cigarette smoke.


Reverse osmoses remove salt from water very effectively, especially when used in combination with carbon filters. But before you buy a reverse osmosis system, you should know what it does to your water.

Most RO systems sold for use at home can remove 99% of salt and other minerals from drinking water. However, they won’t remove any contaminants or bacteria. You still need to filter your water through a carbon filter after using a reverse osmosis unit.


Reverse osmosis systems remove sediment from water with a pre-filter before forcing water through a semi-permeable membrane to remove dissolved salts.

Once the water leaves the membrane, it goes through a post filter to cleanse the water before entering a dedicated faucet.


Reverse osmosis removes up to 98% of chloramines from water. Chloramine is a chemical compound used to disinfect drinking water. It’s added to public water supplies to kill bacteria and viruses.

But it doesn’t actually clean the water. Instead, it leaves behind harmful chemicals called trihalomethanes. These chemicals cause cancer and birth defects.


Arsenic is a naturally occurring element found in rocks and soil. But it’s also present in groundwater. And it’s especially dangerous for pregnant women and children.

Reverse osmoses remove arsenic from water. Water flows through a semipermeable membrane. The contents of water, including arsenic, pass through the membrane and are removed from the water.


Reverse osmosis systems will take out VOCs sometimes, but only if they have a carbon pre-filter or post-filter. By itself, the reverse osmosis process can not take out VOCs

The VOCs will pass through the membrane just like oxygen does.


Activated carbon filters are added to reverse osmosis systems to remove chemicals and heavy metals from water. Activated carbon is a porous material that attracts and holds molecules.

Once the molecules are attracted to the surface of the activated carbon, they become trapped inside the pores of the activated carbon.

This process works well for removing herbicides, pharmaceuticals, and other harmful substances from water.


Reserve osmosis removes pesticides from water. It works by forcing water through a membrane that traps pesticides. Then the treated water passes through a second membrane that removes any remaining pesticide residue.

Is Reverse Osmosis Water Safe?

You may think that drinking reverse osmosis filtered water is safe, but there isn’t any scientific proof to support that claim. There is virtually no tried-an-tested evidence to suggest drinking reverse osmosis purified water is harmful to your overall health.

However, if you have certain medical conditions, such as severe acid reflux or gastric ulcers, drinking reverse-osmosis purified water might cause problems.

Drinking reverse osmosis-purified filtered water won’t harm your health unless you have specific medical conditions. You should consult your doctor before making any changes to your current lifestyle.

What are the Advantages of Reverse Osmosis Filters?

The benefits of reverse osmosis filters go beyond just cleaning up water. They’re also great at filtering out bacteria, viruses, and parasites. They’re especially useful for treating water that contains high levels of lead, mercury, arsenic, nitrates, and pesticides.

They’re also great to use in combination with carbon filtration systems since they can remove organic compounds that may cause problems with carbon filters. There are some other advantages of reverse osmosis filters.

  • Easy to install
  • Cost considerably less
  • Retains the healthy minerals
  • Don’t waste any water
  • Lower risk of water going stale / tasting bad

What are the Disadvantages of Reverse Osmosis Filters?

There are several disadvantages to using reverse osmosis water filtration. First off, it wastes significantly more water than it produces.

Second, it removes some healthy minerals present in water and decreases its pH level. And finally, it requires expensive installation and maintenance costs.


Is It Healthy to Drink Reverse Osmosis Water?

If you’re wondering if it’s safe or healthy to drink reverse osmosis water, then the answer is yes. There is virtually no evidence to suggest that reverse-osmosis water is harmful to human health.

Does Reverse Osmosis Water Remove Healthy Minerals from the Water?

Reverse osmosis removes more than 90-99 percent of all the impurities from the drinking water, including minerals. But most of these minerals in excessive amounts are unhealthy for human consumption.

Does Reverse Osmosis Waste Water?

Yes, reverse osmosis generates a lot of wastewater. But that doesn’t mean you should avoid using it. There are plenty of benefits to using reverse osmosis. You can save money on your water bill, reduce your carbon footprint, and purify your drinking water.


In conclusion, reverse osmosis removes almost all impurities from your drinking water. This includes heavy metals like lead, mercury, arsenic, cadmium, and chromium; pesticides and herbicides; bacteria; viruses; and pharmaceuticals.

In fact, according to the EPA, reverse osmosis systems produce water that meets or exceeds federal standards for safety and purity.

Reverse osmosis systems are also very energy efficient. They use less than half the electricity needed to run traditional water filtration methods. That means you won’t have to worry about paying exorbitant rates on your electric bill.

Plus, because reverse osmosis systems filter water through membranes rather than using chemicals, they leave behind fewer harmful chemical residues. So whether you want pure water for cooking, cleaning, or drinking, a reverse osmosis system is the perfect solution.

Joanna G. Lackey

Hi, I'm Joanna, a writer freelance writer who specializes in topics about health and nutrition. I live in the Pacific Northwest with my husband and three children. I'm a mom to two dogs and a cat. I love reading, writing, and taking photos.