Does Reverse Osmosis Remove Microplastics?

We independently review everything we recommend. If you buy through our links, we may earn a commission. Learn More.
Does Reverse Osmosis Remove Microplastics_Best RO For Microplastic Treatment

We can all agree, the thought of drinking plastic is truly cringeworthy. Microplastics are an alarming issue because of the negative health repercussions if ingested in high amounts. This harmful substance must be removed from your water for your safety! But what is the best way to do it? Does reverse osmosis remove microplastics?

This article will delve deeper into what microplastics are, how to detect if your water has them, and how effective is RO as a treatment method. 

What Exactly Are Microplastics in Drinking Water?

Microplastics in drinking water are plastic particles that have a diameter of fewer than 5 millimeters [1]. In comparison, this is about the size of a grain of sand, making it difficult to see with the naked eye. 

There are two types of microplastics, primary and secondary. Primary microplastics are created directly for commercial purposes in items like clothes, textiles, cosmetics, and packaging. Whereas secondary microplastics are a derivative of larger plastic products like water bottles naturally disintegrating over time.

How Do Microplastics Get Into Drinking Water?

Microplastics are so small, they frequently sneak through most water filter systems. These particles come from various sources but are most common in the oceans and our Great Lakes. They come from the breakdown of oversized plastic items, and cosmetics, as well as the natural breakdown of plastic [2].  Generally, microplastics get into our drinking water through these channels:

  • Water runoff from storms
  • Wind and water currents
  • Microbeads from beauty products and toothpaste
  • Plastic debris from larger plastic products

As plastic is broken down from sun and water exposure, it takes hundreds (sometimes thousands!) of years to decompose into harmless particles [3]. You’ve probably seen shocking photos of trash all around the oceans and seas, with fish tangled in discarded nets or birds nesting in the trash on the shore. Most of what you see are contributors to microplastics.

Source: Collaborating Centre on Sustainable Consumption and Production (CSCP)

Consuming a very minuscule amount of microplastics will not be immediately fatal, but they have long-term negative health impacts. This is why it’s crucial to reduce or eliminate microplastics from our lives, starting with our drinking water.

How Long Does It Take Plastic To Decompose

Plastic can take thousands of years to decompose, which is why it’s harmful to the environment and humans alike. Here is a chart showing the time it takes common plastic goods to decompose:

Plastic WasteYears To Decompose
Plastic Bags20 Years
Nylon Fabric40 Years
Foam Plastic Cups50 Years
Plastic Bottles450 Years
Nylon Fishing Line600 Years

Are Microplastics In Drinking Water Harmful

Due to the prevalence of microplastics, it shouldn’t be surprising that we frequently ingest them in our drinking water. Research has shown that we may be ingesting around 5 grams of plastic weekly from the water we consume, as well as the food we eat and the air we breathe. 

Microplastics have various chemicals deemed harmful to human health. When we consume microplastics from our water and food (like fish and other seafood), our bodies absorb microplastics and their toxins. These microplastics and chemicals enter and accumulate in our blood, organs, and fat cells [4].

When we ingest microplastics from water, they come with toxic chemicals that may affect hormone levels and inflammation of the stomach lining. Research shows that those with inflammatory bowel disease have more microplastics in their feces, which may be the cause of their symptoms.

Moreover, microplastics may also be carriers. Bacteria, viruses, parasites, and other disease-causing pathogens. You might experience food poisoning symptoms because of it.

How Does Reverse Osmosis Remove Microplastics?

Fortunately, there are ways to remove microplastics from drinking water, with reverse osmosis being one of the most effective treatments. Reverse osmosis systems use a multi-stage filtration system with a semi-permeable membrane to remove up to 99.9% of harmful contaminants. The pores in a RO membrane are only 0.0001 micron. Water is forced through the membrane so that only the smallest H2O molecules are able to make it through while microplastics are flushed away with the waste water.

How Does Reverse Osmosis Filter Microplastic_RO Membrane Diagram For Microplastic Treatment

If you want to ensure safe and healthy drinking water, a home filter solution is highly recommended. Most treatment facilities are not able to effectively remove microplastics from our water.

“However, a large part of the world’s population does not currently benefit from suitable water and wastewater treatment systems.”

World Health Organization (WHO)

So, to answer our original question “does reverse osmosis remove microplastics?” Yes, it does!

Reverse osmosis filtration systems don’t only remove microplastics, but also other common chemical contaminants like PFAS, fluoride, lead, bacteria, and lead. It can also reduce harmful contaminants like radium, arsenic, and more. 

How Much Microplastics Does Reverse Osmosis Remove?

RO membranes have pores of 0.0001 microns, while microplastics are 5 millimeters, so RO’s are capable of removing 100% of microplastics. However, this will depend on the type of RO membrane you have and its pore size.

Furthermore, a recent 2021 study demonstrates that membrane filtration technology is most effective at removing nano and micro-plastic particles than alternatives. This was found in data collected for both laboratory-scale and real-scale studies.

Regarding microplastic treatment, “the membrane filtration method also displayed a 100% removal efficiency.”

Water Science and Technology

Some RO systems may be more effective at capturing microplastics and other contaminants than others. It all depends on the quality and specs of the particular model. We will get into key considerations for choosing the best RO system for microplastics a little later, or jump there now.

How To Test For Microplastics In Water

How can you detect if your drinking water contains microplastics? Here are three ways to test:

  • Certified Laboratory Test: We recommend using the Freshnss Labs water test kit for microplastics. It is the most effective way of detecting if your drinking water contains microplastics. Simply collect and mail a water sample from your home, which will then be tested in a certified lab. You’ll receive a detailed analysis of the number of not only microplastics but also dozens of other contaminants in your tap water. You can check the databases mentioned next, however, each home has different water issues, and getting a specific test is most accurate. 
  • Environmental Working Group (EWG) Database: This database provides a panoramic map view of what your location’s drinking water quality looks like. Simply search for your zip code to get an idea of whether your home’s water has a high concentration of microplastics.
  • Consumer Confidence Reports (CCR): Each city is required to submit annual water quality results per the EPA. You can check the CCRs of your location, just like the EWG database. They provide water quality reports to the public.

Key Considerations For Reverse Osmosis Systems

Your Water Source

As mentioned above, it is critical to know the composition of your home’s water. Whether you have well water or city municipal water, it may contain other impurities that need to be addressed other than plastics. This is the starting point for fine-tuning the best RO for microplastics. It could be the case that your water is just fine and you don’t need to spend money on a filter at all!


RO filtration systems that have industry certifications are an indication of quality. The best-known certification is from NSF/ANSI. If your RO system has an NSF certification, specifically to standard 58, you can have peace of mind it has been rigorously tested. NSF has a database to search for all certified products and systems.

Type Of System

There are two main types of RO systems: point-of-use and point-of-entry.

Point-of-use systems are the most common and typically come in the form of an under sink unit. These types of units will treat water from a single sink (usually under the kitchen sink). As far as under sink options, there are tank-based or tankless systems. I encourage you to read our article on tankless vs tank systems to see all the differences. The last point-of-use option is a countertop reverse osmosis system. Countertop units are ideal because they require no installation and are just as effective as their under sink counterparts.

A point-of-entry system is also known as a whole house reverse osmosis system. They are installed at the main water entry of your home. If you have heavy water contamination and need to purify the entire home’s water, this is the best option.

Cost and Maintenance

It is important to factor in both upfront price and ongoing maintenance costs to get the total cost of ownership. A tank-based reverse osmosis is the most affordable and costs on average $200 – $700. A tankless RO system is more efficient, so they cost on average $300 – $900. RO filter replacement costs will average around $100 per year depending on the filter types and how harsh your water is.

Alternative Microplastic Water Filter Options

Besides reverse osmosis, there are other potential at-home methods used to treat microplastics, including:

  • Boiling Water: Boiling water does not remove microplastic from water. People frequently ask if boiling water will remove microplstics, but it will not. Boiling water can eliminate bacteria in water, but the water will not be pure, nor will it remove microplastics, industrial chemicals, pesticides and more.
  • Granular Activated Carbon (GAC or Charcoal Filters): Granular Activated Carbon (GAC) filters can reduce microplastics in water by 56.8% – 60.9% the water. However, granular activated carbon is known to have “channeling” after use, which allows microplastics to pass through into your drinking water [5].
  • Carbon Block Filters: Carbon block filters are a bit better than GAC filters with smaller pores, but the pore size of RO systems is more effective in removing almost all microplastics. Carbon block filters are another option, which would have carbon particles less than 0.18 millimeters.
  • Ion Exchange Resins: This is a water technology that can remove toxic metals from water but is not extremely effective in reducing microplastics compared to RO systems and a microplastic water filter. 
  • Distilling Water: Water distillers can separate microplastics from water during distillation, filtering out a significant number of microplastics. However, some microplastics are fine enough to remain suspended in the air. As a result, these fine microplastics may be carried with evaporated water and condense in the water chamber. 

Drawbacks of Using Reverse Osmosis for Microplastics Treatment

It’s important to note that reverse osmosis filtration systems also have a few disadvantages, including: 

  • Wastes Water: Because of the high level of purification conducted during the reverse osmosis process, an average RO system will waste 4 gallons of water per 1 gallon purified. Thankfully new tankless units are much more efficient and can produce up to 3 gallons on purified water using only one gallon of water.
  • Filter replacement costs: Like all home filtration methods, RO systems require regular maintenance to operate at peak effectiveness. Depending on the type of RO system it may have multiple filter stages. Most pre- and post-filters need to be replaced every 3-6 months and cost about $30. While the RO membrane can last up to 24 months and cost about $100.
  • Removes Healthy Minerals: Reverse Osmosis filtration is so effective it even removes the healthy minerals from drinking water like calcium, potassium, and magnesium. Fortunately, there are several methods to add back minerals to RO water that we discuss in this remineralization article.
  • Requires Installation: Under sink RO systems require a little bit of installation. It can be a DIY a project, but a professional plumber can also have it completed in under 2 hours. A countertop RO requires in installation, however. It only requires access to an electrical plugin.

FAQs For Microplastic Water Treatment

How can I avoid microplastics in water?

The best way to avoid microplastics in your drinking water is to get an at-home water treatment system. Studies have shown that RO filtration systems are the most effective way to eliminate nano- and micro-plastic from water by removing 100% of them. Additionally, drinking plastic bottled water is a frequent source of water impurities that leach into the water.

Can water filters remove microplastics? 

At-home water filters such as reverse osmosis, GAC, and carbon block filters are capable of removing microplastics. You will want filters with smaller pores for them to be effective in removing microplastics in your tap water. 

Do Brita Filters remove microplastics? 

No, Brita filters are not effective at removing microplastics in drinking water. It may reduce a small amount of plastic, but they serve a different purpose and are more effective at reducing aesthetic impurities like odor and smell. This is because Brita filters use basic carbon or charcoal that do not completely remove microplastics.

Does the Berkey water filter remove microplastics?

There are no test results that indicated a Berkey gravity filter can remove 100% of microplastics and are as effective as RO systems. However, it’s known to filter down to about 2 microns or less. 

Article Sources

Freshnss uses only the highest-quality sources to support the facts used in our articles including: government organizations, independent studies, peer-reviewed journals, and lab testing results. Read our editorial review guidelines here to learn more about how we verify and fact-check our writing to keep our content reliable, accurate, and trustworthy.

  1. What Are Microplastics?, National Oceanic and Atmospheric Administration (NOAA)
  2. Plastics In Cosmetics, UNEP
  3. How Long Does It Take Garbage To Decompose, Northeast Illinois Council
  4. Microplastics in human blood and lungs: an urgent case for scientific research, The Sea Cleaners
  5. Granular Activated Carbon Management At A Water Treatment Plant, University Of Johannesburg
      Enable registration in settings - general