Microplastics in Drinking Water & How Reverse Osmosis Can Help Protect Your Home

Over the past decade, scientists have sounded the alarm on a new form of pollution that’s nearly invisible — microplastics. These tiny particles, smaller than 5 millimeters, are now found in our oceans, soil, air, and even the water coming out of our taps.

While the long-term health impacts of microplastics are still being studied, the evidence is clear: they’re everywhere, and they’re hard to avoid. Understanding where these particles come from, how they get into drinking water, and what can be done to reduce exposure has become a growing concern for homeowners who care about the quality of their water.

What Are Microplastics?

Microplastics come from two main sources:

1. Primary microplastics, which are intentionally manufactured at microscopic sizes — such as microbeads used in cosmetics or industrial abrasives.

2. Secondary microplastics, which form when larger plastic waste breaks down over time due to sunlight, friction, and environmental wear.

Everyday items like plastic bottles, synthetic clothing, food packaging, and vehicle tires all shed microplastic particles that eventually find their way into rivers, lakes, and groundwater sources.

How Microplastics Enter Drinking Water

Microplastics are now being detected in both surface water and groundwater, meaning they can appear in municipal systems and private wells alike.

• Runoff and wastewater carry microplastics from cities, roads, and washing machines into waterways.

• Treatment limitations: Even advanced municipal treatment plants are not fully equipped to remove the smallest microplastic fragments.

• Infrastructure: Plastic pipes and fittings can also release particles into the water supply over time.

Recent studies have found microplastics in bottled water, tap water, and even ice and snow samples from remote mountain regions — underscoring how pervasive the problem has become.

Health Concerns and Unknowns

The potential health risks of consuming microplastics are still under investigation, but early research raises serious questions.

Scientists have found that microplastic particles can carry chemical additives and absorbed pollutants, such as heavy metals, flame retardants, and endocrine disruptors. There’s also evidence that they may cause inflammation and oxidative stress when inhaled or ingested, although long-term studies in humans are ongoing.

While we can’t yet quantify the exact risks, many public health experts recommend minimizing exposure wherever possible — much like we already do with lead, chlorine byproducts, and other water contaminants.

Can Water Filters Remove Microplastics?

Not all filters are created equal when it comes to microplastics.

• Basic carbon filters, such as those found in pitcher systems or fridge filters, can reduce some larger particles but often fall short against micro- and nano-sized plastics.

• Sediment filters can help capture larger fragments (>5 microns), but they won’t trap smaller particles effectively.

• Reverse Osmosis (RO) systems, however, offer the most comprehensive protection currently available for household use.

Why Reverse Osmosis Works

Reverse osmosis is a highly effective filtration method that forces water through a semi-permeable membrane with microscopic pores — typically around 0.0001 microns. For perspective, that’s about 100,000 times smaller than a human hair.

Because microplastics range in size from about 1 micron down to nanometers, RO membranes are capable of removing the vast majority of these particles — along with other contaminants like heavy metals, PFAS (“forever chemicals”), and dissolved solids.

Numerous independent studies have shown that RO systems can remove 90–99% of microplastic particles from water, depending on their size and the system’s design.

A Balanced Approach

While reverse osmosis offers a proven way to reduce exposure to microplastics in drinking water, it’s only one part of a broader solution.

Reducing plastic waste, supporting sustainable packaging, and improving municipal filtration infrastructure are all essential steps toward addressing the root cause of the problem.

For homeowners, though, ensuring that your drinking and cooking water is free from as many contaminants as possible is a practical and immediate action — one that brings peace of mind every day.

Microplastics remind us that pollution doesn’t always look dirty. Sometimes it’s invisible, odorless, and sitting quietly in our glass of water.

While science continues to uncover the full extent of their impact, one thing is certain: taking steps to filter them out today can help safeguard your family’s water quality for the future.

Reverse osmosis isn’t a luxury — it’s a line of defense against the growing number of microscopic pollutants entering our environment.