How to filter microplastics from water?

Disclaimer: When you purchase through links on this page, we may earn an affiliate commission.

Even the cleanest tap water comes loaded with millions of microplastics particles that can interrupt hormones and wreak havoc on your health. Determining how to filter microplastics from water in your home is essential to your family’s health. Unfortunately many common water filters from the store or in your fridge are not rated for filtering particles as small as microplastics and will do nothing to filter out these dangerous materials. However there are several methods that do an excellent job of filtering microplastics and as the pollution problem grows and consumer awareness increases we will see more filter brands begin to design new products with microplastics in mind.

Officially speaking microplastics are any plastic particle smaller than 5mm (5000 microns)[1] in length. Particles on the upper end of this cutoff are not a major concern because they are not only large enough to be filtered out by even low grade water filters but they are also big enough to be visible to the human eye. As far as accidental ingestion is concerned, microplastics below the 10 microns range are our primary concern. It’s in this range that many commercially available water filters stop reliably filtering out particles and where they can slip into the bloodstream and the lymphatic system.

How to filter microplastics from water?

A 2020 study of sea water in Japan found microplastic particles as small as 2.5 microns [3]. So for a filter to be effective it must be rated to filter out particles at least this small. Microfiltration is effective at removing particles within this range. Ultrafiltration and nanofiltration remove even smaller particles and will also remove microplastics.

Reverse Osmosis

Reverse osmosis is the gold standard in water filtration methods, filtering particles down to .0001 microns in size [2]. This is overkill for all known microplastics but goes further to remove viruses and aqueous salts. However, reverse osmosis filters are the most expensive option costing at least several hundred dollars and requiring installation. Ongoing water utility usage costs are also high because a reverse osmosis filter discards 5 gallons for every gallon of filtered water.

Water distillation

A water distiller boils water while capturing the water vapor separately and leaving the contaminants behind. Only contaminants with a higher boiling point can be removed thorugh distillation. It is likely that most microplastics will be eliminated through distilation but because certain dangerous chemicals like benzene will evaporate along with the water and therefore not be removed, we do not recommend water distillation as a standalone water treatment process.

Carbon block

Carbon block filters are a convenient and performant solution to remove microplastics from water. These filters vary but the highest rated ones can remove .5 micron particles– so check your specific filters rating before buying. If the cost or hassle of a reverse osmosis filter deters you, a water pitcher with a built in carbon block filter rated for microfiltration is a great option.


Q: Do Berkey water filters remove microplastics?

A: Berkey filters have shown in tests to remove viruses many times smaller than microplastics[4]. It stands to reason that they also filter out microplastics.

Q: Does ZeroWater filter microplastics?

A: Zero water claims to filter out 99.9% of all microplastics and independent lab testing has confirmed this[5]. Additionally, ZeroWater’s 5 stage filter includes a 1 micron filter stage which would filter out the smallest known microplastics. Keep in mind that unlike the all metal Berkey filter, the ZeroWater pitcher is made of (BPA free) plastic.

Q: Do Brita filters remove microplastics?

A: We could not find any claim or lab test confirming the Brita can remove microplastics. 

Q: Does well water need to be filtered for microplastics?

A: Microplastics have been found everywhere from tap water, to bottled water and well water. A study from Utah State University found serious contamination in rainwater in the western US [6]. It’s likely this result would replicate in most parts of the world.

Q: How can I test if my water is contaminated with microplastics?

A: Testing for microplastics requires a lab. There are several companies offering services to test samples of water you send them.

The health effects caused by unprecedented contamination of food and drinking water with microplastics may not be understood for quite some time but planning how to filter microplastics from water in your household is worthwhile. Doing so can be as simple as buying and using a carbon block water pitcher or as complicated as buying and installing a heavy duty reverse osmosis system under your faucet.


Leave a Comment