What is the Difference Between PFAS and PFOA

PFAS and PFOA are two types of chemicals widely used in various industries. Artificial chemicals, unlike natural ones, are created through human processes. These include plastics, medicines, pesticides, and even everyday items like cleaners. 

What is the difference between PFAS and PFOA? PFAS is a larger group of man-made chemicals, whereas PFOA is a specific type of PFAS.

Key Areas Covered

1. What is PFAS 
      – Definition, Features 
2. What is PFOA
      – Definition, Features 
3. Similarities Between PFAS and PFOA
      – Outline of Common Features
4. Difference Between PFAS and PFOA
      – Comparison of Key Differences
      – Answers to Frequently Asked Questions

Key Terms

PFAS, PFOA, Per- and Poly-Fluoroalkyl Substances, Perfluorooctanoic Acid, C8

Difference Between PFAS and PFOA - Comparison Summary

What is PFAS

PFAS stands for per- and poly-fluoroalkyl substances.  It is a large group of man-made chemicals having nearly 6000 members. Its carbon fluorine bond is its major characteristic. Each carbon atom in the PFAS molecule have fluorine atoms. This bonding creates a highly stable structure. In fact, this strength is used in several applications.

The length of the carbon chain can vary, and this variation in length results in different chemical properties. Perfluorinated (PF) chains, where all carbon atoms bond with fluorine, are the most resistant to degradation. Meanwhile, polyfluoroalkyl (poly-F) chains have some hydrogen atoms replacing fluorine, making them slightly less stable.


The strength of the carbon-fluorine bond grants PFAS certain properties. Some of them are water and stain repellence, thermal stability, and surface tension reduction. In addition to all these properties and uses, PFAS are persistent in the environment as they do not readily breakdown. Moreover, they accumulate in the bodies of soil, water and living organisms. This results in occurrence of health issues from long term exposure.

What is PFOA

PFOA, (perfluorooctanoic acid) is also known as C8. It is a type of man-made chemical belonging to the group of PFAS. PFOA has an 8-carbon chain saturated with fluorine atoms. This repels water and oil. Hence, it is used in the production of Teflon coatings, fire resistant materials, and industrial processes. PFOA has a higher strength but there are drawbacks too.


The strong carbon-fluorine bonds make the compound extremely resistant to degradation. This persistence also leads to bioaccumulation, where PFOA can build up in the bodies of animals and humans through contaminated water, food, or even dust inhalation. Therefore, it should be used with necessary controls.

Similarities Between PFAS and PFOA

  1. Both belong to the class of man-made chemicals known as per- and polyfluoroalkyl substances (PFAS).
  2. Due to the strong bonds, both have gained properties such as water and stain repellence, thermal stability, and the ability to reduce surface tension.

Difference Between PFAS and PFOA


  • PFAS, which stands for per- and poly-fluoroalkyl substances, is a large group of man-made chemicals with nearly 6000 members, whereas PFOA, which stands for perfluorooctanoic acid, is a type of man-made chemical belonging to PFAS.


  • PFAS is a large group of chemicals, while PFOA is one specific molecule.

Fluorinated Carbon

  • Not all PFAS chemicals have a fully fluorinated carbon chain like PFOA.


  • The vast number of PFAS chemicals leads to a wider range of properties compared to PFOA.


PFAS is a large group of man-made chemicals with around 6000 members, while PFOA is a specific type of PFAS with an 8-carbon chain. Thus, this is the main difference between PFAS and PFOA. Both share certain properties in common, such as water repellence, but they have some differences too. Both are associated with harmful environmental effects and health effects.


1. Is PFOA the same as PFAS?

No, PFOA is not the same as PFAS, but PFOA is a type of PFAS. PFAS stands for per- and polyfluoroalkyl substances. It’s a large group of man-made chemicals known for being very stable and resistant to water, heat, and oil.

2. Is Teflon considered PFAS?

Yes, Teflon is considered a PFAS. Teflon itself is a brand name for a coating, and the main chemical used in that coating is called PTFE (polytetrafluoroethylene). PTFE belongs to a subgroup of PFAS called fluorinated polymers.

3. Is stainless steel a PFAS?

No, stainless steel is not a PFAS (per- and poly-fluoroalkyl substance). Stainless steel is a metal alloy primarily made of iron, chromium, and nickel. PFAS are a group of human-made chemicals with a carbon-fluorine backbone.

4. Are PFAS cancerous?

The link between PFAS and cancer is a current area of research. Certain PFAS are classified as possible carcinogens: Perfluorooctanoic acid (PFOA), the most studied PFAS, was upgraded to a human carcinogen in 2023.

5. What are the uses of PFAS?

PFAS are used in non-stick cookware, water resistant clothing and textiles, food packaging, and in fire-fighting foams.


1. “Perfluorooctanoic Acid.” Wikipedia. Wikipedia Foundation.
2. “Our Current Understanding of the Human Health and Environmental Risks of PFAS.” United States Environmental Protection Agency. 

Image Courtesy:

1. “PFAS Biomagnification” By Yanishevsky – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “Perfluorooctanoic acid” By Edgar181 – Own work (Public Domain) via Commons Wikimedia

About the Author: Hasini A

Hasini is a graduate of Applied Science with a strong background in forestry, environmental science, chemistry, and management science. She is an amateur photographer with a keen interest in exploring the wonders of nature and science.

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