The Role of PFAS Impacting Carbon Fluxes

In part 4 of our conversation with Ralph Mead and his group, they talked about the knowledge gaps that exist in understanding the long-term environmental transport of per- and polyfluoroalkyl substances (PFAS) (1).

In part 5 of this interview, they talk about climate change and how it impacts carbon fluxes, describing the role of PFAS in these environments.

Below is some of our conversation with Ralph Mead and his team. To listen to their full remarks, watch the video below.

Question: How do you see climate changes impact carbon fluxes? What is the role of PFAS in these environments?

Ralph Mead: The research community, rightly so, is very focused on having water that is clean to drink and food that is safe to consume, and ultimately on reducing exposure to humans and for environmental health, which is important, but all things lead to the sea, right? There’s a major drainage basin and river in our area, the Cape Fear River, that drains a very large percentage of the state. There are a variety of industrial discharge points along the river. Some of those areas have PFAS-laden waste. Ultimately, what happens in the freshwater is going to make it down to the coast. By no means does that negate the impact of PFAS. And so, going to your question, what happens to PFAS once in the coastal zone, tying that in with climate change and sea level rise is a big unknown. From the literature and from what work we've done in the lab, particles (like sediments or organic matter suspended in water) can quickly bind to PFAS, right? So, if you imagine a particle as it moves down the river, starting in the freshwater end of the river, relative ionic strength is going to be lower, but as soon as that particle reaches the coastal area, that ionic strength is going to increase. And so, what role does the increasing ionic strength have in releasing sorbed PFAS back into the dissolved phase? I think that's a really big unknown for a lot of PFAS compounds. I think having a better understanding of the role that the coastal zone salt marshes play as a sink, and potentially as a source of PFAS, exposure to seafood, and also to the area that we recreate in, is important.

To watch the earlier clips from our interview with Ralph Mead and his group, you can access them in the references (1–4).

References

1. Wetzel, W. Understanding the Movement of PFAS in the Environment. LCGC International. Available at: https://www.chromatographyonline.com/view/understanding-the-movement-of-pfas-in-the-environment (accessed 2025-04-09).
2. Wetzel, W. Inside the Laboratory: The Mead Group at UNC Wilmington and the North Carolina PFAS Testing Network. LCGC International. Available at: https://www.chromatographyonline.com/view/inside-the-laboratory-the-mead-group-at-unc-wilmington-and-the-north-carolina-pfas-testing-network (accessed 2025-04-09).
3. Wetzel, W. The Challenges of Characterizing PFAS in the Environment. LCGC International. Available at: https://www.chromatographyonline.com/view/the-challenges-of-characterizing-pfas-in-the-environment (accessed 2025-04-09).
4. Wetzel, W. The Interactions Between Bacterial Communities and PFAS. LCGC International. Available at: https://www.chromatographyonline.com/view/the-interactions-between-bacterial-communities-and-pfas (accessed 2025-04-09).