Some things stay in the world a long time.
They are in many things we use. They can be in rain and water. These things can get into fish. Then we might eat the fish. We must be careful. Do you know what is in your water?
Some man-made chemicals are very strong.
They help keep things clean. They can stop oil and water from soaking in. You might find them in yoga pants or carpets. They are also in shampoo and phone screens.
These chemicals stay in the world for a long time. They can get into the soil and the rain. They can even move into fish. When people eat the fish, the chemicals can get into them too. This can make people sick.
We are still learning how to stay safe.
PFAS are a large group of man-made chemicals.
There are millions of these chemicals. They are made of carbon and fluorine atoms. These atoms stay stuck together very tightly. This makes the chemicals very strong.
People use PFAS in many things. They help products resist heat, oil, and water. You can find them in yoga pants and carpets. They are also in shampoo and phone screens. They are even used in firefighting foam.
These are often called "forever chemicals." This is because they do not break down easily. They move through soil and water. They can even get into the rain.
PFAS can build up in living things. This is called bioaccumulation. This happens when a chemical stays in a body. It can also move up the food chain. This is called biomagnification.
When small animals eat the chemicals, they stay in their bodies. Larger animals then eat those small animals. The amount of chemical grows larger at each step. This can reach humans who eat fish or wildlife. These chemicals may cause health problems like cancer or thyroid disease.
PFAS are a huge group of man-made chemicals. They are made of carbon and fluorine atoms joined together. There are many different types of these substances. Some groups say there are only 8,000 types. Other groups, like PubChem, list 7 million different chemicals.
These chemicals are very useful for many jobs. They help products resist heat, oil, grease, and water. Because they are so strong, they are used in many common items. You might find them in yoga pants, carpets, or shampoo. They are also in phone screens, food packaging, and even makeup like lipstick.
These chemicals work in a special way. Some have a part that hates water and a part that likes it. This helps them act as surfactants. This means they can change how liquids move on a surface. They are very stable because the bond between carbon and fluorine is so strong. This strength is why they are often called "forever chemicals." They do not break down easily in the world. Instead, they move through the soil and the water.
People have used these chemicals for a long time. The widespread use of PFAS began in 1938. This happened when someone invented Teflon, a special coating. Since then, many companies have made these substances. Most are made by only 12 large companies. In 2023, the market for these chemicals was worth about $28 billion. Companies make about $4 billion in profit every year from them.
Because they last so long, they can cause big problems. PFAS can move from water into the air when waves hit the shore. This means they can end up in the rain. They have even been found in remote places like Antarctica. These chemicals can build up in living things. This is called bioaccumulation. When small animals eat them, the chemicals stay in their bodies. When bigger animals eat those small animals, the amount of chemical grows. This is called biomagnification.
This buildup can eventually reach humans through food. For example, fish in the United States often have high levels of PFAS. Eating them can increase the amount of chemicals in a person's blood. This is a concern because PFAS can cause many health issues. Some may cause cancer or thyroid disease. They can also affect how a body grows or how the immune system works.
Because of these risks, many countries are trying to use fewer PFAS. Some companies are even stopping the sale of products that contain them.
Per- and polyfluoroalkyl substances, often called PFAS, are a large group of man-made chemicals. They are synthetic organofluorine compounds. This means they are built with fluorine atoms attached to an alkyl chain. Because there are so many variations, different groups use different definitions. The EPA toxicity database, DSSTox, lists 14,735 unique compounds. However, the PubChem database lists as many as 7 million chemicals in this group.
These chemicals are highly useful because they are very stable. This stability comes from the strong bond between carbon and fluorine. Many PFAS act as fluorosurfactants. A surfactant is a substance that changes how liquids behave on a surface. These chemicals have a hydrophobic tail that repels water. They also have a hydrophilic head that likes water. This allows them to reduce the surface tension of water effectively. Because they repel both oil and water, they are known as lipophobic and hydrophobic.
Widespread use of these substances began in 1938. This was when Teflon, a fluoropolymer coating, was invented. Teflon is a substance that resists heat, oil, grease, and water. Today, PFAS are used in many everyday products. You might find them in waterproof nylon, yoga pants, or carpets. They are also used in shampoo, cosmetics like lipstick, and food packaging. Other uses include firefighting foam, mobile phone screens, and electrical insulation.
Because these chemicals do not break down easily, they are called "forever chemicals." They are persistent organic pollutants. This means they stay in the environment for a very long time. PFAS move through soil and water. Researchers found that they can even move from water to the air when waves hit the land. This can lead to PFAS entering the rain. They have been found in remote areas like Antarctica. Studies show that 31% of groundwater samples in a 2024 study contained harmful levels.
PFAS also move through the food web through two processes. The first is bioaccumulation. This is when a chemical builds up inside a single living thing. The second is biomagnification. This happens when the concentration of the chemical grows as it moves up the food chain. For example, small organisms eat contaminated sediment. Larger animals then eat those organisms. In some cases, concentrations in animals can be 5,000 times higher than in the water.
This buildup poses serious risks to human health. Exposure has been linked to many different conditions. Some PFAS are known carcinogens, which means they can cause cancer. Others are endocrine disruptors that interfere with hormones. Linked health issues include thyroid disease, high cholesterol, and obesity. They can also cause decreased immunity and fertility issues. In the United States, the cost of diseases linked to PFAS is estimated between $6 billion and $62 billion.
The global community is now trying to manage these risks. The Stockholm Convention on Persistent Organic Pollutants has regulated PFAS since 2009. Some places, like the European Union and China, plan to phase them out. However, major producers like the United States and Malaysia have not ratified the agreement. The economic impact is massive. The PFAS market was worth $28 billion in 2023. Cleaning up pollution in the UK and Europe could cost over £1.6 trillion over 20 years.
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