All About PFAS


What are PFAS?

PFAS are a family of fluorochemicals, a combination of carbon and fluorine, often called  per- and poly-fluoroalkyl substances.  The strength of the carbon-fluorine bonds in these compounds means they do not break down as quickly or easily as many other synthetic compounds. 

There are thousands of PFAS compounds, which have been used since the 1940s in many household items such as cookware, waterproof and stain resistant clothing and goods, cosmetics, cleaning products, electronics, packaging, and fire suppression foam. 

The most studied PFAS compounds are those containing a chain of eight or more carbon molecules. Specifically, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are the focus of many recent studies.  These two compounds have been voluntarily phased out of production in the United States but remain present in the environment from past uses. In the U.S., testing shows higher levels of PFOA and PFOS concentration around military installations, airports, and training facilities using fire suppression foam.  .

PFAS for the Public Good

Not all PFAS are the same, so it follows they will not impact human health in the same manner and therefore should not be regulated as one large group. There are some historical instances where the use of long-chain PFAS compounds arguably outweighed the potential health impacts, and there are currently new, less problematic iterations of the fluorochemicals that have significant beneficial uses.

As noted, the historic use of PFOA- and PFOS-containing firefighting foam is the source of concern in some areas. The foam remains the most effective mode of suppressing high-risk hazardous fires such as aircrafts, military facilities, and flammable liquid storage. However, use of the foam has led to ‘hot spots’ of high groundwater concentrations around those facilities. More recently, non-PFOA and PFOS formulations of firefighting foam have largely replaced the legacy product, but non-fluorinated formulation are still less effective than foam containing some version of a PFAS compound.

In addition, there is significant research into developing new PFAS compounds for some of the same beneficial uses. For example, new chemistry has been developed for water and stain resistant applications, which has undergone significant scientific scrutiny and have shown to present to significant human health or environmental risk.

There exists a very high standard of continuous research and review for manufacturers to use new PFAS compounds. Scientists work closely with regulators to understand any potential human health and environmental impacts before they are put into production.

But the continued discussion of PFAS as a group of ‘dangerous chemicals’ has caused some interest groups to call for a ban all compounds, despite the scientific evidence showing that many pose no risk to human health or the environment and provide great benefit for every day life.


Photo Courtesy of Limnotech

Photo Courtesy of Limnotech

The Trouble with Testing for PFAS

The existence of PFAS compounds in so many everyday products makes it difficult to obtain a water sample for testing. Many items normally used during collection and testing can easily contaminate a sample.

In addition, a sample with a high concentration of PFAS can contaminate the laboratory equipment, resulting in a shut down of the testing process while equipment is decontaminated and cleaned. There is only one testing method approved by the EPA for 18 PFAS compounds in drinking water samples.