Can Berkey Remove Microplastics From Water?

Updated September 2026

Microplastics, plastic fragments and fibers smaller than 5 millimeters, have been found in surface water across the world, and more recently in the groundwater that supplies wells and springs. This page covers what the research has found, what kinds of filters have been studied for microplastic reduction, and exactly what we can and cannot say about Berkey.

How Do You Remove Microplastics From Drinking Water?

Laboratory studies on point-of-use filtration have looked at three common technologies: granular activated carbon, carbon block, and reverse osmosis. All three physically capture particles, and all three have shown reductions in microplastic counts in published testing. The practical limit is pore size: a filter can only stop particles larger than the openings water passes through, so a filter rated to the micron or sub-micron range will catch far more than a coarse sediment screen.

Boiling does not remove microplastics, and switching to bottled water does not help either. In the same research program that found microplastics in 83% of tap water samples across 14 countries, bottled water tested at roughly double the concentration, and a 2024 Columbia University study using newer imaging methods counted an average of about 240,000 plastic particles per liter in bottled water, most of them nanoplastics too small for older methods to detect. Our tap versus bottled water microplastics guide covers that research in detail.

Does Berkey Remove Microplastics?

We want to be direct about this, because a lot of pages on the internet are not. Black Berkey elements, which ship with every new Berkey system while supplies last, and Berkey Phoenix elements, the authorized replacement, have each been independently tested against 200+ contaminants: heavy metals, PFAS, pesticides, pharmaceuticals, VOCs, chlorine and its byproducts, and more. Microplastics are not on that list. No accredited lab has run a microplastics-specific challenge test on either element, and we will not attach a number to a claim that has not been tested.

What the existing data does establish is a tested reduction range, not a microplastics-specific result. Black Berkey elements have been independently tested down to 24 to 26 nanometers, and that tested range suggests larger plastic fibers should be removed, since the fibers in the Orb Media tap water study were around 10 microns, or 10,000 nanometers, in diameter. That is an inference from the tested range, not a microplastics lab result, and we label it as such. Full details are on the Berkey Knowledge Base.

Microplastics Have Reached Groundwater, Not Just Rivers

A 2019 study published in the journal Groundwater was the first to document microplastic fibers in fractured limestone aquifers, the karst groundwater systems that supply roughly 25% of the world's drinking water.

Researchers analyzed 17 groundwater samples from springs and wells fed by highly fractured limestone aquifers in Illinois, 11 near the St. Louis metro area and 6 in rural northwestern Illinois. Sixteen of the seventeen samples contained microplastic fibers. The highest concentration, 15.2 fibers per liter, came from a spring near St. Louis, and overall the groundwater concentrations were similar to those measured in streams and rivers around Chicago.

"Plastic in the environment breaks down into microscopic particles that can end up in the guts and gills of marine life, exposing the animals to chemicals in the plastic," explained John Scott, a research scientist at the Illinois Sustainable Technology Center and co-author of the study. "As the plastics break down, they act like sponges that soak up contaminants and microbes and can ultimately work their way into our food supply."

Water seeps through fissures and cracks in limestone and can carry sewage and runoff from roadways, farmland, and landfills into the aquifer, Scott explained. The samples also contained personal care and household contaminants alongside the plastic fibers, which points to onsite wastewater systems as one source: polyester fibers shed in the wash, travel into the septic system with laundry water, and can leach through soil with effluent into groundwater, particularly where surface water and groundwater interact readily.

Because microplastic levels in drinking water are not regulated and no risk assessment existed at the time, the authors were careful not to state what those concentrations mean for health. Scott's own summary was that the study was only the tip of the iceberg:

"Even if we quit plastics cold turkey today, we will still deal with this issue for years because plastic never really goes away," Scott said. "It is estimated that 6.3 billion metric tons of plastic waste have been produced since the 1940s, and 79 percent of that is now in landfills or the natural environment. To me, it is such a weird concept that these materials are intended for single use, yet they are designed to last forever."

What This Means for a Berkey Owner

If microplastics are your primary concern, the useful questions to ask any filter brand are the same three: what pore size or micron rating is documented, has the filter been challenge-tested for microplastics specifically, and are the reports public. For Berkey, the honest answers are sub-micron, not yet, and yes for everything that has been tested. That puts it ahead of most gravity filters on documentation and on par with them on microplastics, where the whole category is waiting on dedicated testing.

Frequently Asked Questions

Journal reference: Samuel V. Panno et al., "Microplastic Contamination in Karst Groundwater Systems," Groundwater, January 2019, doi: 10.1111/gwat.12862. Naixin Qian et al., "Rapid single-particle chemical imaging of nanoplastics by SRS microscopy," Proceedings of the National Academy of Sciences, January 2024, doi: 10.1073/pnas.2300582121.