In the last few years, people all around the world have become more aware of sanitation and the potential health threats posed by bacteria and other microorganisms. Everyone wants to learn how to protect their health which is understandable. There is no scientific evidence that covid-19 can be transmitted via water supplies. That said, there are bacteria, viruses, and other pathogens that can be transferred via water. In this article, we will take a closer look at a common question, can RO filtration remove bacteria?

What is Reverse Osmosis?

RO purification is a mechanical water filtering system that uses a semi-permeable filter with tiny pores and osmotic pressure to remove a wide variety of contaminants. These contaminants are left behind on the surface of the filter, and only water molecules and trace elements can pass through. The filter membrane has pores that are 0.0001 microns in diameter.

To put this into some perspective, certain bacteria, such as E.coli and salmonella, range from 0.2 up to around 4 microns in size. So, they are far too big to pass through filter pores, and they are effectively removed from the water.

According to data published by the CDC, an RO filtration system is extremely effective at removing the following.

  • Bacteria: E.Coli, Salmonella, Shigella, Campylobacter, and more.
  • Viruses: Hepatitis A, Rotavirus, Norovirus, Enteric, and more.
  • Protozoa: Cryptosporidium, Giardia, and more.

As you can see, the simple answer to the original question, “Can reverse osmosis systems kill microorganisms?” is not strictly true. The microorganisms are removed from the incoming water supply, but no disinfection takes place. Many people prefer this manual filtration system because no chemicals are added to the water.

What About Chlorine Disinfection?

Chlorine has been added to public water drinking water for decades, and it has been proven to be an effective disinfectant. In recent years, some water suppliers have switched to chloramine, which is chlorine mixed with ammonia to boost the efficacy. But, there is some data to suggest that chlorine byproducts are harmful to health and some microorganisms are becoming resistant. For these reasons, many people are choosing to install their own water treatment systems as a final line of defense. It’s also worth noting that a RO filtration system has a granular activated carbon (GAC) filtration stage to remove chlorine that could damage the RO filter membrane.

Are There Any Alternatives?

Aside from RO filtration systems, the best alternative is ultraviolet (UV) purification. UV-light wavelengths actually disrupt the DNA of microorganisms if the exposure time is sufficient. This actually removes the replication capability from the microorganism, which renders it harmless to human length. The efficacy of UV purification on water is 99.99%, with no need for chemical treatment and no harmful chemical byproducts. All that’s required after installation is power, that’s roughly equivalent to running a 60w lightbulb.

If you want to clean your drinking water to a higher standard, contact your local water treatment specialist.

By EcoWater Systems.
EcoWater Systems of Nebraska is the largest water treatment company in the state and is a member of Water Quality Association.