Short-Chain vs. Long-Chain PFAS

PFAS stands for perfluoroalkyl and polyfluoroalkyl substances. These manmade chemicals are often referred to as “forever chemicals” because they seem to last forever in your environment. They’re used in all kinds of consumer products and leach into your soil, air, and water.

Generally, there are two major categories: short-chain PFAS and long-chain PFAS. This blog explores both short- and long-chain PFAS. It also takes a closer look at PFAS effects on your health, the current government regulations, and the legal steps you can take if you’ve been affected.

What Are the Effects of Short- and Long-Chain PFAS?

According to the Environmental and Energy Study Institute, research shows that roughly 97% of Americans who were tested have PFAS in their bodies. Scientists are still looking into the lasting health impacts of PFAS. ⁽¹⁾

Right now, it looks like PFAS chemicals can cause real health concerns. Some of these PFAS health concerns include: ⁽²⁾

• Increased risk of cancer.
• Liver damage.
• Thyroid damage.
• Immune systems damage
• Reduced fertility and damage to your reproductive systems.
• Problems with childhood development.

Each PFAS is made up of a different combination of chemicals. They can damage your body in different ways.

By far, the biggest concern is cancer. Some PFAS may be more likely to lead to kidney cancer, others to testicular cancer, breast cancer, ovarian cancer, endometrial cancer, liver cancer, or thyroid cancer. ⁽³⁾

PFAS and Your Hormones

Another huge concern is the effects PFAS have on your immune system and endocrine system — the system that regulates your hormones. Research suggests both short- and long-chain PFAS can disrupt how your hormones work. Your metabolism can even be affected. ⁽⁴⁾

Studies also suggest PFAS can lead to higher levels of a hormone called thyrotropin that can lead to: ⁽⁵⁾

• Obesity.
• Diabetes.
• Chronic kidney disease.
• Insufficient antibody response.
• Damage to your lungs, particularly children with asthma Polycystic ovary syndrome-related infertility.

Hormone disruption is a big deal. PFAS are endocrine disruptors. Research suggests PFAS may interfere with molecules in your hormones. In particular, two short-chain PFAS — PFBS and PFHxS — may disrupt your thyroid gland. ⁽⁶⁾

PFAS in Blood Levels

Researchers have tested the blood levels of PFAS in people from the United States, Italy, Germany, Belgium, the Czech Republic, China, Poland, and Korea. People exposed to PFAS through the work they do have higher blood levels of PFAS. ⁽⁷⁾

Also, the blood levels of specific PFAS that have been in use longer are higher than blood levels of PFAS that have been in use for a shorter period of time. Long-chain PFAS have been around longer than short-chain PFAS. ⁽⁸⁾

Blood levels of long-chain PFAS are decreasing since they are being replaced worldwide. However, blood levels of short-chain PFAS are increasing, partly because “they are more mobile and persistent in aquatic ecosystems.” ⁽⁹⁾

Short-chain PFAS were not studied yet for very long. Early studies suggest they may cause the same health risks that long-chain PFAS do. ⁽¹⁰⁾

PFAS and Pregnancy

Another effect is that PFAS seem to have a greater impact on women’s hormones than men’s. This finding is really concerning because we don’t know how PFAS blood levels affect a woman’s pregnancy.

A woman may pass along PFAS effects to her unborn baby. Once her baby is born, we don’t know how that child’s development might be affected. Both cognitive and behavioral development might be impaired. ⁽¹¹⁾

In recent decades, short-chain PFAS are replacing long-chain PFAS. Short-chain PFAS have four to six carbon atoms. Long-chain PFAS have more, sometimes eight or more. ⁽¹²⁾

Both short-chain PFAS and long-chain PFAS seem to disrupt your hormones and endocrine system. However, in many cases, short-chain PFAS may actually lead to a potentially higher level of hormone disrupting damage than long-chain PFAS. This is particularly true in the case of PFHxS. ⁽¹³⁾

Who Is Affected by Short- and Long-Chain PFAS? 

Everyone who is exposed to short-chain and long-chain PFAS is affected by these toxic chemicals. PFAS exposure may cause the most bodily damage to children, pregnant women, and individuals with compromised immune systems. The amount of the exposure matters. So does the particular type of PFAS. ⁽¹⁴⁾

People who work in manufacturing plants producing certain products may face a greater risk of PFAS exposure. These include production of: ⁽¹⁵⁾

• Firefighting foam.
• Herbicides.
• Cosmetics.
• Solvents.
• Paint.
• Textile protecting substances, such as Gore-Tex.
• Floor polish.
• Kitchenware.
• Food packaging.

Also, people working in particular industries are more likely to experience greater PFAS exposure. These include: ⁽¹⁶⁾

• Construction.
• Motor.
• Aviation.
• Electronics.

Blood testing for PFAS is available. However, test results can’t tell you what health effects you might experience in the future or how you were exposed. ⁽¹⁷⁾

Are You Being Exposed to PFAS?

By law, in most instances, manufacturers who sell products with PFAS do not have to let you know if their products contain PFAS. Even more concerning, manufacturers who market products to children may label those products “green” — even if they contain PFAS. ⁽¹⁸⁾

In 2016, the federal government banned three PFAS from food packaging. However, thousands of PFAs are still not regulated. ⁽¹⁹⁾

Two of the most common PFAS are not made in the U.S. anymore: perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). However, the products we import from other countries are still allowed to contain PFAS. ⁽²⁰⁾

What Are the Differences Between Short- and Long-Chain PFAS?

More than 10,000 different PFAS exist. In scientific terms, each PFAS compound contains at least one perfluorinated methyl group or one perfluorinated methylene group. Basically, each PFAS contains at least one carbon atom combined with two or three fluorine atoms. PFAS are made up of fluorinated carbon. ⁽²¹⁾

In addition to these basic combinations are thousands of variations. These variations depend on how many atoms of oxygen, sulfur, and other elements are combined. Depending on the exact atoms, PFAS can be broken down into other categories: ⁽²²⁾

• PFAAs: Perfluoroalkyl acids include PFOS and PFOA. Within this group there are others, including PFCAs and PFSAs. PFCAs stands for perfluoroalkyl carboxylic acids. PFSAs stands for perfluoroalkyl sulfonic acids.
• Precursors: These PFAS can change and become PFAAs in the world around you.
• Other PFAS: This group of chemicals includes mostly polymers such as PTFE. PTFE is the chemical used in the coating of nonstick cookware.

The science of PFAS can be really complicated. To make things easier to understand, scientists have classified PFAS into two main groups: Short-chain PFAS and Long-chain PFAS. ⁽²³⁾

Short-Chain PFAS	Long-Chain PFAS
PFCAs with a chain of fewer than 7 fluorinated carbon atoms. Also, PFSAs containing a chain of fewer than 6.	PFCAs with a chain of 7 or more fluorinated carbon atoms. Also, PFSAs containing 6 or more.
PFBS, chain of 4 fluorinated carbon atoms.	PFOA, chain of 7 fluorinated carbon atoms.
PFBA, chain of 3 fluorinated carbon atoms.	PFOS, chain of 8 fluorinated carbon atoms.
PFHxA, chain of 5 fluorinated carbon atoms.	PFNA, chain of 8 fluorinated carbon atoms.
Introduced more recently.	Around for decades.
Less research exists.	Studied more.
Meant to replace long-chain PFAS.	Phased out.

Updates on PFAS

As of February 2024, the U.S. Food & Drug Administration said that manufacturers can no longer sell grease-proofing substances to be used in contact with food in the U.S. The goal is to decrease your risk of being exposed to PFAS through the foods you eat. For decades, manufacturers used PFAS in microwave popcorn bags, fast-food wrappers, pet food bags, and cardboard boxes used for take-out food. ⁽²⁴⁾

When it comes to PFAS and the water you drink, the U.S. Environmental Protection Agency (EPA) issued national safe drinking water standards in April 2024. The EPA’s aim is to protect roughly 100 million people from PFAS contaminated water. ⁽²⁵⁾

In addition, the EPA is providing $1 billion to states and territories across the country to test and treat public water systems. Part of the money is going to owners of private wells. ⁽²⁶⁾

Also, in September 2024, the EPA issued water quality concentrations for 10 common PFAS. These standards protect fish and other water life from being exposed to PFAS.

However, everyone benefits when your exposure to PFAS is reduced. Contaminated water hurts communities across the country. ⁽²⁷⁾

How Weitz & Luxenberg Supports People Impacted by PFAS

PFAS are manmade chemicals that existed for decades. All PFAS contain some fluorine and carbon. It’s this strong carbon and fluorine bond that helps these chemicals stick around for a long time — in you and in your environment. People are just beginning to learn about the serious health hazards connected with them.

Long-chain PFAS have longer links of carbon and fluorine. They were invented first. When researchers began learning how dangerous they were, manufacturers came up with alternatives — short-chain PFAS. However, all PFAS pose similar risks of your developing cancer and other serious long-term health complications.

If you or a loved one has been harmed by exposure to PFAS, Weitz & Luxenberg is here for you. We’ve been helping people and communities injured by hazardous chemicals for decades.

We encourage you to reach out to us if you have any questions about short- or long-chain PFAS pollution. We can help you consider your legal options if these chemicals have affected your health and quality of life. There is no charge for a consultation.