Two of the most common water quality questions we hear right now are about PFAS and microplastics. Homeowners are searching, reading, and worrying, and understandably so. But there’s a lot of confusion about what these contaminants actually are, how they differ, and whether you need to worry about one, the other, or both. This article gives you straight answers based on the latest science.
No. They are fundamentally different types of contaminants, though they are increasingly found together and interact with each other in ways that researchers are only beginning to fully understand.
PFAS (per- and polyfluoroalkyl substances) are man-made chemicals — a group of more than 15,000 synthetic compounds used in manufacturing since the 1940s. They are found in nonstick cookware, food packaging, firefighting foam, waterproof clothing, and hundreds of industrial applications. PFAS are called “forever chemicals” because the carbon-fluorine bond at their core is one of the strongest in chemistry. They do not break down in the environment or in the human body. They are invisible, dissolved in water, and have no taste or smell.
Microplastics are physical particles — tiny pieces of plastic material less than 5 millimeters in size, broken down from larger plastic waste or shed from synthetic textiles, tires, and consumer products. Unlike PFAS, microplastics are solid particles you could theoretically see under a microscope. They are not dissolved in water — they are suspended in it.
The simplest way to remember the difference: PFAS are invisible chemicals dissolved in water. Microplastics are tiny physical particles floating in it. Both are widespread, both are concerning, and — critically — both are increasingly found together.
Learn more:
EPA: PFAS Overview
EPA: Microplastics in Drinking Water
Both contaminants reach drinking water through multiple pathways. Many of those pathways overlap, which is part of why they so often appear together.
That last point is important. A 2024 University of Illinois study confirmed that both PFAS and microplastics accumulate in the biosolids produced by wastewater treatment plants. When those biosolids are spread on agricultural land, both contaminants migrate into soil and groundwater together.
Yes — and this co-occurrence is more than coincidental. A comprehensive 2025 review published in Toxics (MDPI) confirmed that microplastics act as vectors, concentrators, and secondary sources for PFAS. Meaning microplastic particles actively attract and carry PFAS from the surrounding water.
A separate 2025 study published in ScienceDirect found that certain plastic polymers — particularly polyamide — can adsorb PFAS so effectively that they capture nearly all available PFAS from the surrounding water onto their surface. When those microplastic particles are ingested, the PFAS they carry may be released directly into body tissue.
Researchers increasingly find that the two pollutants co-exist in water, food, and the environment, where microplastics may carry or interact with other chemicals — and both can persist in living tissue. This has prompted calls for a more integrated approach to assessing environmental and human health risks rather than evaluating each contaminant in isolation.
The practical implication for homeowners: if you have one, you likely have some level of the other. And the combined exposure may be more harmful than either contaminant alone.
Both are serious concerns — and because they increasingly interact with each other, the question of which is “worse” is becoming less useful than understanding the combined risk.
PFAS research is further advanced — the health evidence is more established, which is why the EPA acted to set federal limits in 2024. Microplastics research is younger but moving fast, and the early findings are serious enough that most public health experts recommend taking precautionary action now.
When microplastics carry PFAS into the body, the concern compounds. A 2025 study in Environmental Science & Technology found that co-exposure to PFAS and microplastics produces synergistic toxic effects. The combined harm may be greater than adding up the individual effects of each contaminant separately.
Learn more:
NIEHS: Microplastics and Human Health
CDC: PFAS Health Information
No — and the regulatory gap between them is significant.
PFAS reached a major milestone in 2024 when the EPA finalized the first-ever federal maximum contaminant levels (MCLs) for six PFAS compounds in drinking water. The limit for PFOA and PFOS — two of the most studied and widespread PFAS — was set at just 4 parts per trillion, one of the lowest contaminant limits ever established. Municipal water systems must comply by 2031. PFAS contamination must now be tested and reported.
Microplastics have no federal MCL in the United States as of 2026. No country in the world has yet established an enforceable drinking water limit for microplastics. Water utilities are not required to test for or report microplastics levels. The EPA is conducting research, and in late 2025 seven U.S. governors petitioned the EPA to require nationwide microplastics monitoring — but enforceable rules remain years away.
This means that even if your city water meets the new PFAS limits, it may still contain significant microplastic contamination that is completely unmonitored and unreported. And for private well owners, neither contaminant is regulated or tested by any government agency.
Find your annual Consumer Confidence Report at EPA.gov
EWG Tap Water Database — search your local supply
This is one of the most practical questions homeowners ask. The good news is that the most effective technology for both contaminants is the same: reverse osmosis.
Here is how the main technologies compare for each contaminant:
| Filter Type | PFAS Removal | Microplastics Removal |
|---|---|---|
| Reverse osmosis (RO) | ✅ Highly effective — 94%+ reduction confirmed in independent testing | ✅ Highly effective — filters at nanometer level |
| (UF) Ultra Filtration Systems | ❌ No, not meant for PFAS reduction | ✅ Yes, effective for microplastics filtration |
| Solid carbon block (≤1 micron) | ⚠️ Partial — effective for some PFAS compounds | ✅ Effective for many microplastics at correct pore size |
| Whole house GAC / catalytic carbon | ⚠️ Not recommended as stand-alone PFAS solution | ⚠️ Not recommended as stand-alone microplastics solution |
| Standard pitcher filters | ❌ Generally not effective for PFAS | ❌ Generally not rated for microplastics |
For homeowners concerned about both PFAS and microplastics — which increasingly means most homeowners — the most complete strategy is:
Under-sink reverse osmosis system for drinking and cooking water — the single most effective step for both contaminants simultaneously.
Solid Carbon Block for drinking and cooking water, effective at correct pore size of below 1 micron. See our selection of Carbon Block under sink filters.
Ultra Filtration Systems for a powerful level of whole house filtration between standard sediment filters and reverse osmosis systems. It removes particles far smaller than cartridge filters while allowing dissolved minerals to pass through — and without producing wastewater. UF systems filter down to 0.015 microns. Ultrafiltration is ideal as a standalone whole-house clarity filter or as a pre-treatment stage ahead of carbon filters, softeners, or specialty media systems.
Whole house filtration systems to improve water quality at every tap, reduce chlorine and chemical byproducts, and protect plumbing and appliances addressing hard water, if an issue in your water. Learn more about our whole house bundles.
PFAS Whole House Filter if testing confirms elevated PFAS levels that require targeted treatment
Reverse Osmosis Systems at Clean Water Store
Ideally both — but with realistic expectations about what testing currently looks like for each.
PFAS testing is more established. Certified laboratory tests for PFAS in drinking water are widely available, reasonably priced, and provide actionable results. If you live near a military base, airport, chemical plant, or agricultural area where biosolids were applied, PFAS testing is especially important.
Microplastics testing is still developing at the consumer level. Standardized, affordable microplastic testing for homeowners is not yet widely available. The honest reality is that given how widespread microplastic contamination has been confirmed to be, most water treatment professionals — including our team — recommend installing proven filtration rather than waiting for affordable testing to catch up. If you do want to consider a lab test, we carry this Simple Lab option.
The most practical starting point for most homeowners is a comprehensive water quality test that covers regulated and unregulated chemical contaminants, paired with filtration that addresses the broadest range of concerns.
👉 Get a Water Test Kit from Clean Water Store
For city water homeowners who want comprehensive whole-house protection from chlorine, chemical byproducts, hard water, and a broad range of contaminants — while pairing with an RO system for PFAS and microplastics at the drinking water level — our top recommendation is a whole house filter bundle for your water chemistry with added Reverse Osmosis and Ultra Filtration to target microplastics.
👉 Learn more about Ultra Filtration Systems
👉 Browse All Whole House Filtration + Softening Bundles
👉 Shop Reverse Osmosis Systems
👉 Talk to Our Water Experts — Mon–Fri 7:30 AM–3:30 PM PT
Read the full guides in our contaminants series:
What Are Microplastics in Drinking Water and Should I Be Worried?
Microplastics in City Tap Water: Are You Protected?
Are Microplastics in Well Water? What Private Well Owners Need to Know
What Are PFAS Forever Chemicals and Are They in My Water?
Article last updated March 24, 2026 by Author
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