By Harry Looney

PFAS is short for per- and polyfluoroalkyl substances, a large group of man-made chemicals used for decades in products designed to resist grease, water, heat, or stains. You may have heard them called “forever chemicals.” That nickname is not a formal legal or scientific term, but it captures an important idea: many PFAS break down very slowly, so they can remain in water, soil, animals, and people for a long time.¹

PFAS were used because they solved real-world problems. They helped make firefighting foam effective on fuel fires. They were used in some food wrappers, nonstick coatings, stain-resistant fabrics, and certain industrial processes. The problem is that the same qualities that made PFAS useful also make them hard to manage once they escape into the environment.1,2

PFAS can move from products and industrial uses into water, soil, food, wildlife, and people over time.

Why PFAS matter

Many people in the United States have already been exposed to at least some PFAS. That does not mean everyone will become sick because of PFAS, and it does not mean all PFAS act the same way. It does mean public health agencies have a reason to pay close attention. EPA says studies have linked exposure to some PFAS with harmful health effects in humans and animals, while also noting that many questions remain, especially because there are thousands of different PFAS chemicals.1,2

Research discussed by EPA and other health agencies has linked certain PFAS exposures with concerns such as changes in cholesterol, effects on the immune system, pregnancy-related concerns, developmental effects in children, interference with the body’s hormones, and increased risk of some cancers. The key words are important: some PFAS, some levels of exposure, and ongoing research.1,2,3

Why this matters at home

For families, the most practical question is often simple: “Could PFAS be in the water I drink, in fish I catch, or in products I use?” That is why government monitoring, local water reports, and health guidance matter so much. Good information helps people make steady, informed decisions rather than panic.

How people can be exposed

PFAS exposure can happen in more than one way. Drinking water is one of the biggest public concerns, especially when a water source is near a place that used or released PFAS. People can also be exposed through certain foods, fish from contaminated waters, workplace contact, indoor dust, and some consumer products. Firefighters and workers in certain industries may face higher exposure than the general public. Young children may also be more vulnerable because they eat, drink, and breathe more for their body size and spend more time on floors and around dust.1,2,3

Businesses should pay attention too. A small business may not make PFAS, but it might still handle products, wastewater, packaging, textiles, cleaning chemicals, or industrial processes that involve PFAS. For some companies, the issue is now both environmental and regulatory: what is discharged, how it is monitored, and whether it could affect wastewater treatment systems or downstream drinking water sources.

Effects on animals and the environment

PFAS are not only a human health issue. They can also build up in fish and wildlife. EPA notes that PFAS can be found in water, air, fish, and soil across the country, and that some PFAS can build up in animals over time. That matters for ecosystems, hunting and fishing communities, and people who rely on local waterways for recreation or food.1,2

When PFAS enters rivers, lakes, or soil, they do not always stay in one place. They can move with water, settle into sediments, be taken up by living things, and sometimes show up later in fish tissue or drinking water systems. This is one reason agencies look at PFAS as a "source to tap" issue: what enters the environment upstream can eventually affect homes and businesses downstream.