What’s Really in Your Tap Water? The EPA Is Looking for More Than 1,000 Potential Contaminants

For decades, drinking water testing has focused on a defined list of contaminants that utilities are required to monitor. But as science advances, researchers are finding that there may be far more in our water than traditional testing has been designed to detect.

In September 2026, the U.S. Environmental Protection Agency announced a new drinking water study that will use advanced testing methods to screen for more than 1,000 potential pollutants, including PFAS, pharmaceuticals, and other emerging contaminants.

It’s an important reminder: “meets drinking water standards” and “contains nothing potentially concerning” are not necessarily the same thing.

Why Is the EPA Looking for More Contaminants?

Water quality regulations are built around contaminants that have been identified, studied, and assigned enforceable standards.

But our ability to detect chemicals is constantly improving.

There are thousands of chemicals used in manufacturing, agriculture, medications, personal care products, household products, and other industries. Some can eventually make their way into groundwater, rivers, reservoirs, and other drinking-water sources.

That doesn’t mean every chemical detected in water is present at a harmful level. Detection alone does not establish health risk.

What it does mean is that scientists are increasingly able to ask a bigger question:

What else is in our water that we haven't traditionally been looking for?

The EPA says its new study will use advanced analytical methods to better understand the presence of a broad range of potential drinking-water pollutants.

PFAS Testing Has Already Shown Why Broader Monitoring Matters

PFAS — often called “forever chemicals” because of their persistence in the environment — are one of the clearest examples of how drinking-water monitoring continues to change.

Between 2023 and 2025, public water systems participating in the EPA's Fifth Unregulated Contaminant Monitoring Rule tested for 29 different PFAS compounds as well as lithium. The final national dataset was released in August 2026.

This type of monitoring helps researchers and regulators understand where emerging contaminants are being detected and at what concentrations before decisions are made about future drinking-water standards.

And PFAS aren't the only substances receiving attention.

The EPA has also proposed monitoring for another group of currently unregulated drinking-water contaminants under its next monitoring cycle.

Does Your Water Utility Test for Everything?

No — and realistically, it can't.

Public water systems are required to meet federal and state drinking-water regulations, but those regulations cover specific contaminants and testing requirements.

There are many substances for which no federal drinking-water limit currently exists.

That distinction is important.

A municipal water report can be incredibly useful for understanding your water quality, but it should be viewed as a snapshot of the contaminants your utility is required to test for — not necessarily an exhaustive inventory of everything that could possibly be present.

Start With Your Own Water

Water quality can vary dramatically from one location to another.

Your water source, local infrastructure, plumbing, surrounding agriculture or industry, and even the age of your home can influence what ultimately comes out of your tap.

That's why we always recommend starting with your water rather than choosing filtration based on a generic list of contaminants.

A few good places to begin:

• Look up your local utility's annual Consumer Confidence Report.

• Find out whether your home receives municipal water or private well water.

• Pay attention to contaminants detected in your specific area.

• Consider independent water testing if you have concerns that aren't addressed in your municipal report.

• Choose filtration media based on the contaminants you're actually trying to reduce.

Filtration Isn't One-Size-Fits-All

There is no single filtration material that removes every contaminant.

Different technologies and filtration media are designed for different jobs.

Sediment filtration, activated or catalytic carbon, KDF media, specialized ion-exchange media, and reverse osmosis all work differently and target different categories of contaminants.

That's one of the reasons Santé systems use combinations of filtration media rather than relying on a single generic carbon filter.

The goal shouldn't simply be to have a water filter.

The goal is to have the right filtration for your water.

The Bigger Picture

The EPA's latest research doesn't mean that America's tap water suddenly changed.

What is changing is our ability to identify and measure what's in it.

As testing technology becomes more sophisticated, our understanding of drinking water will continue to evolve — and that's a good thing.

The more we know about what's in our water, the better equipped we are to make informed decisions about the water we drink, cook with, and use every day.

At Santé for Health, we've always believed that good filtration starts with understanding your water first.

Not sure where to start? Send us your city, water report, or the contaminants you're concerned about, and we're happy to help you determine which filtration options make the most sense for your water.