PFAS 101: What you need to know about perfluoroalkylated substances—and why
December 11, 2017
PFAS—found in firefighting foam, microwave popcorn bags, and cosmetics—are present in our food chain and we’re still studying their impact
Perfluoroalkylated substances (PFAS) are a new, emerging contaminant, and they’re receiving a lot of media attention lately. So, what’s all the PFAS, I mean,?fuss?about? There are great benefits to using PFAS in consumer and industrial products, but there are also drawbacks when considering their impact on the environment and the health of people, plants, and animals. In this blog, I’ll explore some of those benefits and drawbacks—and how they can impact you.
PFAS are found in many consumer goods, from microwave popcorn bags to water-resistant clothing. They’re also found in many industrial products, such as firefighting foams. PFAS are shown to be resistant to heat, oil, grease, and water, making them difficult to remove from the environment.?
PFAS can be found in many common consumer products.
What makes PFAS so resistant??
PFAS are made up of carbon chains of varying lengths, where the carbon-hydrogen bonds have been replaced by carbon-fluorine bonds, which is one of the strongest chemical bonds. At one end of the carbon chain are chemical groups that repel certain compounds. The other end of the chain includes chemical groups that can attract certain compounds. This results in strong and stable polymers and surfactants. Because of their persistence, and the potential health risks to humans and the environment, some PFAS have been, or are being, phased out from use in many parts of the world. But other PFAS are taking their place.
Because of the stability of PFAS, they have been used in many applications/products since they were first produced in the 1940s including adhesives; cosmetics; cleaning products; water-, stain-, and oil-repellent coatings for fabric and paper; and specialized chemical applications such as aqueous film forming foam (aka firefighting foams).
Where can you find PFAS?
The answer: just about everywhere, but they are increasingly being found around military sites, airports, firefighting training facilities, in run-off from fire incidents, landfills, and production facilities. What is really interesting is that PFAS are also being found in northern environments, far from the most common sources of PFAS. This indicates that airborne PFAS particles from production facilities can travel some distance—further proof of how stable and resistant PFAS are.
Firefighters use foam to extinguish a blaze.
So why do we need to be concerned??
PFAS research is still very limited, and new information is constantly becoming available. We do know that PFAS are found in the environment in groundwater, surface water, soil, and sediment—and that means PFAS are also being found in the food chain, including in people and in animals such as fish and polar bears. For people, exposure to PFAS is mainly through consumption of drinking water. For animals and plants, exposure is mainly through contact with soil and surface water.
Once PFAS are present in the body, it can take a long time for them to break down, because PFAS are so stable and resistant. What we don’t know a lot about are the long-term effects of PFAS on the health of people, animals, and plants, nor do we have a complete understanding of what happens to PFAS in the environment or how PFAS move through different environments (air, water). Government agencies across the globe, including Canada, are working to better understand how PFAS behave, both in the environment and in the food chain. And what, if any, are the safe levels of PFAS for people, plants, and animals.
If you know or think that you have a site where PFAS-containing products were used or stored (e.g., the use of firefighting foam at a firefighter training facility), the first step is to identify the most likely locations at your site for potential contamination. The next step involves conducting an environmental site investigation to establish if PFAS are present at your site by testing the soil, groundwater, surface water, and/or sediment.
The industry is still learning about PFAS (how they move through the environment, how they impact humans, animals, and plants) and strict laboratory and assessment practices and evaluation criteria are constantly changing. To learn more about how to assess and evaluate PFAS, watch for my next blog. In part 2, I’ll look at sampling and laboratory requirements.?