What is the chemical structure of PFAS?

Per- and polyfluoroalkyl substances (PFAS) are a diverse group of chemicals, and their chemical structures can vary depending on the specific compound. However, they share some common characteristics. PFAS are characterized by a chain of carbon atoms bonded to fluorine atoms. The general structure can be represented as follows:

R-(CF2)n-CF3

In this structure, R represents a functional group or a carbon chain attached to the fluorinated carbon chain; CF2 represents a repeating unit of two carbon atoms bonded to two fluorine atoms; n represents the number of repeating units, which can vary for different PFAS compounds; and CF3 represents a trifluoromethyl group, where a carbon atom is bonded to three fluorine atoms.

Because the fluorine-carbon bond is so strong, it takes an immense amount of energy to break it, which gives PFAS chemicals their characteristic longevity and thus earning the name “forever chemicals.”

What is PTFE and what is it used in?

PTFE stands for polytetrafluoroethylene, which is a synthetic fluoropolymer of tetrafluoroethylene. It is a high-performance plastic known for its exceptional non-stick properties, resistance to heat and chemicals, and low friction coefficient. PTFE is used in various applications, including:

• Non-stick cookware. PTFE is widely used as a non-stick coating in cookware such as frying pans, griddles, and baking sheets.
• Industrial applications. PTFE’s chemical resistance and non-stick properties make it suitable for industrial applications, including lining pipes, tanks, and containers, as well as providing a non-stick surface for conveyor belts and chute linings.
• Electrical insulation. PTFE has excellent electrical insulation properties, making it ideal for insulating wires, cables, and connectors. It is used in a wide range of electronic and electrical applications.
• Seals and gaskets. PTFE’s resistance to chemicals and high temperatures make it suitable for manufacturing seals, gaskets, and O-rings used in industries such as automotive, aerospace, and mechanical engineering.
• Medical applications. PTFE is utilized in medical devices and implants due to its biocompatibility, low friction, and resistance to chemicals. It can be found in catheters, surgical instruments, and prosthetic components.
• Filtration. PTFE membranes and filters are employed in various filtration applications, such as air and water filtration, due to their ability to repel water and resist chemical attack.

Is PTFE a PFAS chemical?

Yes, PTFE is considered a type of PFAS chemical. While PTFE is a type of PFAS, not all PFAS chemicals are PTFE. PFAS encompasses a broad group of chemicals with different properties and uses.

Is PTFE harmful?

PTFE, commonly known as Teflon, is generally considered safe for its intended uses. It has a long history of use in various applications, including non-stick cookware, electrical insulation, and medical devices. PTFE is chemically inert and has a high melting point, which makes it stable and resistant to heat, chemicals, and electricity. Those properties make it a favorable material for laboratory supplies manufacturing. ILT uses PTFE in a variety of products; to learn more about ILT septa and seals, click here.

There are some considerations to keep in mind, however. 

1. When PTFE is heated to high temperatures (above 500°F or 260°C), it can release toxic fumes that can be harmful if inhaled. These fumes are primarily a concern in industrial settings, such as during the manufacturing process or in the event of overheating non-stick cookware. It is recommended to use PTFE-coated cookware within its designated temperature range and to avoid overheating or using damaged PTFE-coated products.
2. If the PTFE coating on cookware becomes scratched, damaged, or worn out, there is a possibility of the underlying metal being exposed. Ingesting or inhaling small metallic particles may not be desirable, so it is advisable to replace damaged or heavily worn PTFE-coated cookware.

As with any chemical or product, it’s important to follow manufacturer instructions, use products within their intended purposes and limitations, and maintain proper ventilation in cooking areas to ensure safety.