What are Teflon and PFOA? Where are they found?
Perfluorooctanoic acid (PFOA), also known as C8, is another man-made chemical. It has been used in the process of making polytetrafluoroethylene and similar chemicals (called fluorotelomers), although it is burned off in the process and is not present in significant amounts in the final product.
PFOA has the potential to be a health problem because it can remain in the environment and the human body for long periods of time. Studies have found that it is present in very low levels in the blood of almost everyone around the world. Higher blood levels have been found in residents of communities whose local water supplies were contaminated with PFOA. Levels for people exposed to PFOA in the workplace may be many times higher.
PFOA and some similar compounds are found in low levels in some foods, drinking water and household dust. Although PFOA levels in drinking water are generally low, they can be higher in some areas, such as near chemical plants that use PFOA.
People may also be exposed to PFOA in ski wax or stain-resistant treated fabrics and carpets. Nonstick cookware is not a significant source of PFOA exposure.
Do Teflon and PFOA cause cancer?
Whether Teflon and other nonstick coatings themselves cause cancer has not been a major focus. The main focus is on PFOA and similar polyfluoroalkyl substances (PFAS) such as perfluorooctane sulfonate (PFOS), perfluorobutane sulfonate (PFBS) and "GenX" chemicals.
Many studies have looked at the potential for PFOA to cause cancer. Researchers used two main types of studies to try to figure out whether this substance causes cancer.
laboratory research
In studies conducted in the laboratory, animals are exposed to a substance, usually in very large doses, to see if it causes tumors or other health problems. Researchers may also expose human cells in lab dishes to the substance to see if it causes the types of changes seen in cancer cells.
Studies in laboratory animals have found that exposure to PFOA increases the risk of certain tumors in the liver, testicles, mammary glands (breasts) and pancreas. Generally speaking, good studies in animals also do a good job of predicting which exposures may cause cancer in humans.
human research
Some types of studies look at cancer rates in different groups of people. These studies may compare cancer rates in a group exposed to a substance to those in a group not exposed to the substance, or to cancer rates in the general population. But it can sometimes be difficult to know what the results of these types of studies mean because many other factors may influence the results.
Studies have examined cancer rates in people who live near or work at chemical plants linked to PFOA. Some of these studies suggest that exposure to PFOA increases the risk of testicular cancer. Studies have also shown a possible link to kidney and thyroid cancer, but the increased risk is small and likely due to chance.
Other studies suggest possible links to other cancers, including prostate, bladder and ovarian cancer. But not all studies have found this link, and more research is needed to clarify the findings.
What do expert bodies say?
In most cases, the American Cancer Society does not determine whether something causes cancer (i.e., is a carcinogen ). Instead, we look to other respected organizations to classify potentially carcinogenic exposures.
The International Agency for Research on Cancer (IARC) is part of the World Health Organization (WHO). One of its goals is to identify the cause of cancer. IARC classifies PFOA as "possibly carcinogenic to humans" (Group 2B), based on limited evidence in humans that it causes testicular and kidney cancer, and limited evidence in laboratory animals.
The U.S. Environmental Protection Agency (EPA) maintains the Integrated Risk Information System (IRIS), an electronic database that contains information on the human health effects of exposure to various substances in the environment. The EPA has not officially classified PFOA based on its carcinogenicity.
In a (non-final) draft report, the EPA's scientific advisory committee reviewed the evidence for PFOA, primarily from studies in laboratory animals, and said "there is suggestive evidence of carcinogenicity but is insufficient to assess carcinogenic potential in humans." . The committee agreed that new evidence would be considered as it became available.
Other agencies have not formally evaluated whether PFOA causes cancer.
What is being done about PFOA (and PFOS)?
The long-term effects of PFOA and similar chemicals are largely unknown, but there are enough concerns to prompt attempts to phase out their industrial emissions.
While the possible long-term health effects of PFOA have yet to be determined, in 2006 the EPA and the eight U.S. manufacturers that used PFOA at the time agreed to a "stewardship plan." The company's goal is to eliminate PFOA from emissions and product ingredients by the end of 2015. PFOA and some closely related chemicals such as PFOS are no longer manufactured in the United States, although they are still manufactured in some other countries and regions and may affect U.S. consumers in certain types of products. Additionally, there are many other PFAS in use and new ones are still being developed.
The EPA currently does not impose limits on the amount of PFOA or related chemicals (such as PFOS) in drinking water. However, the EPA has established health advisories for PFOA and PFOS in drinking water based primarily on the observed health effects of PFOA and PFOS in laboratory animal (rats and mice) studies. The health advisory level for these two chemicals (alone or combined) is set at 70 parts per trillion over a person's lifetime. These recommendations are not legally binding federal standards. They are intended to provide drinking water system operators, as well as state and other agencies responsible for overseeing these systems, with information about the health risks of these chemicals so that they can take appropriate actions to protect residents.
Additionally, EPA is currently considering developing drinking water standards for PFOA and PFOS, which , if adopted, would set legally enforceable maximum contaminant levels (MCLs) for these substances in drinking water.
Should I take steps to protect myself, such as not using my Teflon-coated pans?
There are no risks to humans from using cookware coated with Teflon (or other nonstick surfaces), other than inhaling the fumes from an overheated Teflon-coated pan, which may cause flu-like symptoms. While PFOA has been used in the past to make Teflon in the United States, it is not present (or present in very small amounts) in Teflon-coated products.
Because it is unclear how people may be exposed to PFOA, it is unclear what measures people may take to reduce exposure. People who find higher than normal levels of PFOA or similar chemicals in their regular drinking water sources may consider using bottled water or installing an activated carbon water filter, according to the Centers for Disease Control and Prevention (CDC).
For people who are concerned they may have been exposed to high levels of PFOA, the levels can be measured in the blood, but this is not a routine test that can be done in a doctor's office. Even if testing is done, it's unclear what the results mean about possible health effects.
