What Is PFAS and Why Should You Care?

The Short Answer

PFAS — short for per- and polyfluoroalkyl substances — are a family of more than 15,000 synthetic chemicals that have been manufactured and used in industry and consumer products since the 1940s. They are called "forever chemicals" because they do not break down naturally in the environment or in the human body. They accumulate over time, and they are now detectable in the blood of nearly every American adult and child.

If you have never heard of PFAS before, you are not alone. But the science on them has been building for decades, and the picture it paints is not reassuring.

Where PFAS Come From

PFAS were first developed in the 1940s for their remarkable ability to resist heat, oil, grease, and water. That combination of properties made them incredibly useful, and manufacturers quickly found applications across dozens of industries. Today, PFAS are found in:

• Non-stick cookware (Teflon and similar coatings)
• Waterproof and stain-resistant clothing (Gore-Tex, Scotchgard-treated fabrics)
• Food packaging (fast-food wrappers, microwave popcorn bags, pizza boxes)
• Firefighting foam (AFFF) used at military bases, airports, and industrial sites
• Carpets and upholstery treated for stain resistance
• Dental floss (certain brands use PTFE, a PFAS compound)
• Cosmetics and personal care products
• Industrial manufacturing of semiconductors, electronics, and chemicals

The problem is not just that these products contain PFAS — it is that PFAS leach out of products into the environment, into soil, into groundwater, and ultimately into drinking water supplies. Once released, they travel freely and persist indefinitely.

How PFAS Get Into Your Drinking Water

The most significant route of human exposure to PFAS is through drinking water. PFAS contamination of water supplies happens through several pathways:

Industrial discharge is the most direct source. Facilities that manufacture or use PFAS release them into nearby waterways and soil. Communities near chemical plants, military bases, and airports are disproportionately affected.

Firefighting foam is a particularly concentrated source. Aqueous film-forming foam (AFFF), used extensively at military installations and airports for decades, contains extremely high concentrations of PFAS. When this foam is used in training exercises or emergency response, it soaks into the ground and migrates into groundwater.

Landfill leachate is another major pathway. Consumer products containing PFAS end up in landfills, where rainwater percolates through the waste and carries PFAS into the surrounding groundwater.

Wastewater treatment plants are not designed to remove PFAS. When PFAS-containing products are washed down drains, the chemicals pass through treatment facilities and are discharged into rivers and streams — or spread on agricultural land as biosolid sludge.

Once PFAS enter a water source, conventional water treatment does not remove them. Standard filtration and chlorination processes are ineffective against PFAS. This means that even water that has been "treated" by your municipal utility may still contain PFAS.

How Many Americans Are Affected?

The scale of PFAS contamination in the United States is difficult to overstate.

According to the Environmental Working Group's contamination database, updated in early 2026, 176 million people in communities across all 50 states have drinking water that has tested positive for PFAS. A 2020 study by EWG scientists estimated that more than 200 million Americans are served by water systems where PFOA or PFOS — two of the most studied PFAS — were present at concentrations of 1 part per trillion or higher.

The U.S. Geological Survey reported in 2024 that approximately 71 to 95 million people — more than 20% of the country's population — may rely on groundwater contaminated with PFAS for their drinking water.

The CDC's Agency for Toxic Substances and Disease Registry has confirmed that nearly all people in the United States have PFAS in their blood. The chemicals accumulate in the body over years of low-level exposure, primarily through drinking water and food.

What Are the Health Effects?

This is where the science becomes most alarming. PFAS are not inert. They are biologically active chemicals that interfere with the body's normal functions in multiple ways.

The EPA's current scientific review identifies the following health effects associated with PFAS exposure:

Children are particularly vulnerable. Because they drink more water, eat more food, and breathe more air per pound of body weight than adults, their exposure is proportionally higher. Young children also crawl on floors and put objects in their mouths, increasing contact with PFAS in carpets, dust, and toys.

It is worth noting that the EPA concluded in April 2024 that there is no safe level of PFOA or PFOS exposure — meaning even very low concentrations carry measurable health risk. This was the scientific basis for the first-ever national drinking water standards for PFAS, finalized in April 2024.

The Regulatory Situation (And Why It's Complicated)

In April 2024, the EPA finalized the first National Primary Drinking Water Regulation covering six PFAS compounds, setting maximum contaminant levels (MCLs) for PFOA and PFOS at 4 parts per trillion — the lowest level that can be reliably measured. This was a landmark public health achievement, decades in the making.

However, the regulatory picture has since become less clear. In May 2025, the EPA announced it would delay compliance deadlines for water systems until 2031 and signaled it may roll back protections for four of the six covered PFAS. As of early 2026, legal challenges and regulatory uncertainty mean that the protections originally promised are not yet fully in force.

The practical implication for you as a homeowner is this: even if your water utility is in compliance with current regulations, those regulations may not protect you from all PFAS at all concentrations. Water utilities test water at the treatment plant, not at your tap. By the time water travels through aging distribution pipes and your home's plumbing, the contamination picture may look different.

Does Your Water Have PFAS?

The honest answer is: you probably don't know for certain, and your utility's annual water quality report may not tell you.

The EPA's UCMR 5 monitoring program requires public water systems to test for PFAS by 2027. Many utilities have already completed this testing, and results are publicly available. However, the testing covers only a subset of the more than 15,000 known PFAS compounds, and private well owners are not covered at all.

The most reliable way to know what is in your water is to test it directly. A certified lab panel from a service like Tap Score or SimpleLab will test your actual tap water — not utility averages — for PFAS and dozens of other contaminants, and give you a plain-English report explaining what the results mean.

You can also start with our free ZIP code water report, which pulls EPA and EWG data for your specific water utility and gives you an instant picture of what has been detected in your area.

What Can You Do About PFAS?

If PFAS are present in your water, the good news is that effective filtration technology exists. Not all filters are equal, however. Here is what the research shows:

Reverse osmosis (RO) systems are the most effective at removing PFAS. A properly installed whole-house or under-sink RO system can remove 90–99% of PFAS from drinking water. This is the gold standard for PFAS removal.

Activated carbon filters (including pitcher filters like Brita) can reduce some PFAS, but their effectiveness varies significantly by PFAS type, filter age, and flow rate. They are not reliable for comprehensive PFAS removal.

Standard water softeners do not remove PFAS.

A whole-house filtration system that incorporates reverse osmosis technology addresses PFAS at every tap in your home — not just the kitchen faucet. This matters because PFAS exposure also occurs through showering, bathing, and cooking with contaminated water.

The Bottom Line

PFAS are real, they are widespread, and the health evidence against them is serious and growing. The fact that they are in the blood of nearly every American does not mean exposure is inevitable going forward — it means the problem has been building for decades and requires deliberate action to address.

You do not have to wait for regulators to catch up. Testing your water and investing in appropriate filtration are concrete steps you can take right now to reduce your family's exposure.

Start with the basics: Get your free ZIP code water report to see what EPA data shows for your utility. If you want lab-verified results specific to your home, explore certified testing options. And if you are ready to act on what you find, a whole-house filtration system is the most comprehensive solution available.

Sources: U.S. Environmental Protection Agency (EPA), Environmental Working Group (EWG), U.S. Geological Survey (USGS), CDC Agency for Toxic Substances and Disease Registry (ATSDR), National Institute of Environmental Health Sciences (NIEHS), National Cancer Institute (NCI). All health claims are based on peer-reviewed scientific literature and official government sources as of early 2026.