Microplastics in Drinking Water: What You Should Know | Expert Insight

Microplastics are an emerging issue and are commonly discussed among the health, regulatory and scientific communities. They are recognized as a harmful and widespread pollutant with potential, long-term impacts to both natural ecosystems and human health. Virtually unavoidable, microplastics have been detected in the depths of the ocean, our food and water, and even indoor air.

Microplastics are tiny, invisible pieces of plastic (particles less than 5 millimeters in size) that are broken down from various products. Because of their small size, these particles enter the natural environment by traveling through water systems and have been detected in drinking-water sources around the world. Research has found that almost all of us have some level of microplastics in our bodies.

We live in a world where plastics dominate, largely due to convenience and low manufacturing costs. As a result, microplastics originate from a variety of sources:

• Plastic products such as bottles, bags, packaging and other plastic waste. These products release microplastics during manufacturing, and even while being opened.Heat exposure , such as leaving bottled water in cars or direct sunlight, accelerates plastic degradation.
• Synthetic fibers that shed from our clothing during laundry can enter waterways, and can also be found on tire particles from roads and degraded packaging.
• Plastic pipes that may release small particles with age or wear. While wastewater treatment plants remove larger plastics, smaller ones escape and reach drinking water systems.

Due to the overwhelming volume of plastic products around the world, they break down in our landfills and natural environment. Though these products never fully degrade, it can take anywhere from 20 to over 1,000 years to break down, depending on the type of plastic and environmental conditions. As such, these products slowly break off into tiny particles and enter our drinking water systems through natural processes like run-off, stormwater, and other environmental pathways.

“Nanoplastics are all around us” . Microplastics have been found in rivers, lakes, sediments and even in groundwater and rain-water. This has overwhelmed municipal water systems with plastic fragments. While wastewater treatment plants remove many particles, a fraction does escape through runoff, eventually reaching surface water or groundwater used for drinking.

Emerging research suggests that microplastics may pose health risks to humans. They are ingested through food and water and inhalation of airborne fibers and even dust.

Once ingested, microplastics become extremely harmful. They are known to carry chemical additives or adsorb environmental toxins which then enter the body. Although direct evidence is limited, observational studies find that microplastic exposure is suspected to have adverse effects on digestive, respiratory and reproductive systems.

These negative health associations are worrying enough that reducing human exposure is considered urgent.

Many jurisdictions have agreed that microplastics in drinking water must be better understood and managed.

The state of California has taken a leadership role in assessing microplastics in drinking water. The California State Water Resources Control Board adopted a definition of “microplastics in drinking water” which helped to establish a standard testing methodology. A promising signal that more transparency and stronger drinking water monitoring lies ahead.

Michigan has been actively building a policy and monitoring framework for microplastics in drinking water. The Department of Environment, Great Lakes, and Energy (EGLE) announced $2 million to support microplastics research, monitoring in lakes/rivers and drinking water sources. The state also amended the Safe Drinking Water Act requiring testing and reporting of microplastics in public drinking water supplies.

While these policy mechanisms are promising, and may influence others to take action, it is still integral to reduce your personal microplastics exposure.

Yes — using a reliable RO (reverse osmosis) system is one of the most effective methods for removing microplastic particles in drinking water. RO’s very small pore size makes it successful in rejecting many microplastics.

As previously mentioned, using a high-quality point-of-use filtration system (RO or ultrafiltration) is most effective. It’s also important to minimize consumption of plastic products, specifically bottled water, which often contains high numbers of microplastics. Small actions like avoiding heating food in plastic containers and reducing single-use plastics can attack microplastics at the source by reducing plastic waste.

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Microplastics in drinking water is both a modern and evolving challenge. They are invisible to the naked eye, increasingly widespread, and only now becoming the focus of regulatory and scientific attention.

Until microplastics are fully measured, regulated and removed across all systems, you have control over your own exposure. Understanding what microplastics are and how to avoid them will enable you to make informed decisions about your drinking water. Choosing a quality RO system and reducing plastic-derived exposures are among the best steps you can take today.

1. BMC Gastroenterology. (2025). Microplastic exposure disrupts human gut microbiome: A systematic review. BMC Gastroenterology. Link

2. California State Water Resources Control Board – Microplastics in Drinking Water Program. (n.d.). California State Water Resources Control Board. Link

3. Chartres, N., Cooper, C. B., Bland, G., Pelch, K. E., Gandhi, S. A., BakenRa, A., & Woodruff, T. J. (2024). Effects of microplastic exposure on human digestive, reproductive, and respiratory health: A rapid systematic review. Environmental Science & Technology, 58(52), 22843-22864. Link

4. Cho, R. (2025, May 5). Nanoplastics are all around (and inside) us. Lamont-Doherty Earth Observatory, Columbia Climate School. Link

5. Fei, J., Wang, H., Li, Y., et al. (2024). Aging of drinking water transmission pipes during long-term operation as a potential source of nano- and microplastics. Science of the Total Environment, 897, 165418. Link

6. Hernandez, E., Nowack, B., & Mitrano, D. M. (2017). Polyester textiles as a source of microplastics from households: A mechanistic study to understand microfiber release during washing. Environmental Science & Technology, 51(12), 7036-7046. Link

7. Jayavel, S., Govindaraju, B., Michael, J. R., & Viswanathan, B. (2024). Impacts of micro and nanoplastics on human health. Bulletin of the National Research Centre, 48, Article 110. Link

8. Michigan Department of Environment, Great Lakes, and Energy (EGLE). (2025). Microplastics Summit 2025. Michigan Department of Environment, Great Lakes, and Energy. Link

9. Michigan Legislature. (2025). Senate Bill 504 – Microplastics Testing in Drinking Water. Michigan Legislature. Link

10. ScienceDaily. (2025). Microplastics still slipping through water treatment plants. ScienceDaily. Link

11. Sutton, R., et al. (2022). Development and application of a health-based framework for informing regulatory action in relation to exposure of microplastic particles in California drinking water. Microplastics and Nanoplastics (SpringerOpen). Link

12. Water Research Foundation (Project 5338). (2025). Microplastics in Drinking Water Distribution Systems. Water Research Foundation. Link

13. Washington Post. (2025). How to eat and drink fewer microplastics. Washington Post. Link