Water Filters And The Environment: What’s Best For Microplastics And Nanoplastics?

According to a 2018 study, 94% of tap water samples from the U.S. are contaminated with microplastics, the highest level in the world. Another study found bottled water is no purer: 93% of samples from 11 popular brands contain microplastics, each one measuring between 1 micron and 5 millimeters.

Nanoplastics, which are even smaller bits of plastic less than 1 micron in size, are also present in drinking water. In fact, a 2024 study using new technology was able to count microplastics and nanoplastics (MNPs) in water and discovered 240,000 particles—90% nanoplastics—in one liter of water.

“This is orders of magnitude more than the microplastic abundance reported previously in bottled water,” the researchers commented on their findings. The “extraordinary” non-uniformity of the MNPs they visualized sheds new light on our understanding of these ubiquitous contaminants.

The quantity of MNPs in water will continue to escalate—and their size will progressively decrease by continued light and mechanical degradation—as global plastic production increases. 

In fact, that industry produced 441.3 million tons of plastic in 2022, a 1.6% increase over the previous year. Plastic production is expected to grow to a staggering 490.8 million tons by 2025. Over half of it is for single use. These plastics, including the MNPs derived from them, never fully degrade since they are made of indestructible fossil fuels. 

To protect your health from these pollutants linked to a number of serious health conditions including cardiovascular diseases and gut microbiome disruption, you may wonder if there’s a water filter that will remove them. 

The short answer is that one type of water filter removes microplastics. It is only somewhat effective in removing nanoplastics.

Fortunately, there is another way to rid drinking water of MNPs, and it doesn’t rely on plastic filters.

Water filters and microplastics

Despite the marketing to the contrary, there is no water filter on the market that will completely remove all MNPs. Any brand that claims otherwise is guilty of greenwashing.

The best water filter that removes the most microplastics contains a membrane filter with a small enough pore size that will trap almost all (99.9%) microplastics measuring 1 micron or larger. LifeStraw products claim to have this capability. Some of their filters will also block nanoplastics down to 0.02 micron. Note that nanoplastics get much smaller than that.

Research on other home water filtration systems showed granular activated carbon, ion exchange, and reverse osmosis methods were not effective as removing microplastics. In fact, systems with granular activated carbon and ion exchange sometimes produced “filtered” water containing more microplastics than the unfiltered water!    

Water distillation and microplastics

Water distillation is the only way to separate water from MNPs. As water vaporizes, all MNPs are left behind in the distillation chamber. The temperature of boiling water isn’t even hot enough to melt plastics, so MNPs stay in solid form at the bottom of the chamber. Purified water vapor travels through the condensation tube where it reforms into liquid water.

An added benefit of distillation is there are no plastic filters or beads like in all other water purification methods. Since these filters aren’t recyclable, they eventually get discarded, producing more plastic waste, eventually resulting in more MNPs. 

The water distiller I have used for over 13 years without incident which I highly recommend is Steam Pure for countertops. Larger units are available. 

Drop by drop, a gallon of pure water collects overnight or while you’re at work from a stainless steel machine into a glass jar. The water never comes in contact with plastic. Equipped with automatic shut off, there’s no need to worry about overheating an empty water reservoir. 

Critics say distilled water lacks essential minerals required for health and tastes flat. The truth is that food—not water—provides these nutrients. A splash of lemon juice will add zest to its taste if desired. 

Boiling water as a way to remove microplastics and nanoplastics

An inexpensive way to remove microplastics and nanoplastics (MNPs) from water is by boiling. A 2024 study revealed that this method removes 90% of MNPs when the water is hard. Only 25% of MNPs are removed from soft water. 

During boiling, minerals form crystalline structures (incrustants) which encase the MNPs and build up like limescale, similar to what happens in a coffee maker. You remove MNPs when you scrub away the limescale as part of regular cleaning. If you see floating incrustants in the water after boiling, remove them by pouring the water through a standard coffee filter.