Expert Roundtable: Positive Trends in PFAS Research

PFAS research has come a long, way even in the last five years. There are a lot of smart people investing time in PFAS analysis from the industry, academia, the federal government and equipment manufacturers, as well.

Some of the big positives we've seen recently include a few routine regulatory methods, at least for drinking water and wastewater. Now, I think it’s about the science of how to measure PFAS at low levels—that skillset is increasing in the industry. There's also been significant advancements on the analytical equipment manufacturer side to eliminate PFAS background from mass spectrometers and chromatography instruments. Manufacturers have made it a lot simpler to process data, to analyze PFAS and to do routine and regulatory methods so users can get trusted answers that can be used to make policy and management decisions.

I think air is a big area researchers need to look into. Air is something that we cannot discriminate because everyone breathes air 24 hours a day. Knowing the concentrations of elements in the air is pretty important, especially to sensitive populations. The other area that we really need to be focusing on is closing the mass balance of PFAS—measuring these other PFAS that are not on our regulatory target list. We need to understand how prevalent they are, and try to get a holistic picture of how much PFAS is really out in the environment.

There is a bright spot at the end of the tunnel. I was looking at a recent study examining blood levels of PFAS in the United States. The survey took place from 1999 to 2018, and the levels of PFAS and PFOA actually decreased over time. Since the use of those compounds are restricted, you actually see blood concentrations coming down. For PFAS, I think there was a drop about 85% in blood level concentrations and for PFOA about 70%. By addressing these issues and using the right tools to make these measurements, there's a bright spot we'll be able to improve conditions around the world.

Another thing from a technical point of view is the fact that detection limits keep getting lower. It seems researchers are interested in lower detection limits, while the number of target compounds continues to increase. From the point of view of an instrument company like Agilent, we want to make sure labs are future proof. When we develop products for PFAS analysis, we're always looking to the future in the understanding that there's going to be more targets that people are interested in, as well as lower and lower detection levels.

The advancements in non-targeted analysis using high-res mass spectrometry in the past few years have been amazing. There have been improvements in the hardware, but also in newer data processing and data analysis tools that are really accelerating the knowledge we have for PFAS and other contaminants. The workflows for non-targeted analysis are not perfect, there are limitations in terms of standardization and quality control but we are gathering a lot of knowledge about unknown PFAS and transformation products from PFAS.

There are groups like “Best Practices for Non-targeted Analysis of BP for NDA” that is actively working on addressing some of the limitations of non-targeted analysis. All of this knowledge that we are gathering from non-targeted analysis can be then transferred to the more routine environment when we are using targeted work with LC triple quad or a GC-MS. Routine labs can incorporate this newer knowledge into the routine testing of PFAS.

There's been an exponential rise in the number of PFAS research papers globally and I think that’s in part, from great collaboration across academia, regulatory agencies and private stakeholders. This is exciting to see—it is really building a strong foundation for PFAS science and also introducing a number of new scientists to this area. These scientists can have an impact over the coming years as this is a global priority and health concern. Their efforts now will be very much appreciated as this market research area grows and the groups involved now really make significant progress in developing the most appropriate and sensitive workflows for detecting and quantifying PFAS compounds across all sample types.

We see a really good initiative in exposomics—understanding how PFAS compounds can be found in the environment, in our food, and trapped through biological samples such as blood, serum and tissue. We need data on how to regulate and remediate this compound in the future. In particular, this research has included specific advancements in high resolution mass spectrometry for PFAS. This has enabled the identification and measurement of a broader range of compounds due to that ability of leveraging that PFAS library and data processing. This continuous feedback to industry and their regulatory agencies allows prioritization to be made around the different types of PFAS compounds and the various levels they need to be monitored for to make sure we have a strong future in protecting human impact from the presence of this compound.

Lastly, another area of rapid growth is developing PFAS alternatives. What materials can be produced tomorrow that'll have similar functionalities but with reduced environmental and health impacts? This is an active topic for our team and we work with a number of researchers around the globe that are exploring new materials and the use of the latest technology to replace PFAS materials in various applications. They are leveraging similar analytical workflows that you see in the EPA regulatory framework, but are establishing a global collaborative network to characterize these new materials and share what might be the path forward in a PFAS-free environment.

Positive advancements in PFAS research testing I've seen can be divided into two areas—one analytical and the other waste handling. On the analytical side, I've seen some work being done on direct-to-MS technologies such as coated blade spray. Currently, PFAS laboratories tend to be overwhelmed with samples, turnaround times are slow, capacity is at maximum. A direct-to-MS technique that simplifies sample prep and bypasses chromatography can definitely increase the capacity of labs getting more samples out and helping to improve everyone's knowledge of PFAS exposure much more quickly.

On the waste side, current waste destruction techniques such as incineration can't fully break down PFAS compounds. If you incinerate PFAS waste, you're turning large chain PFAS compounds into a number of shorter chain PFAS compounds and then usually emitting these out into the air. There are numerous companies I've talked to that are working on alternative destruction techniques that can fully break down the PFAS so waste destruction doesn't just create more PFAS into the environment.

There is now a big interest in closing the mass balance. When we've been looking at targeted techniques, that's only a fraction of the PFAS compounds that are out in the environment. Most of the historical PFAS research or quantitation has been done with LC Triple Quad, which is a targeted analysis technique so it depends on you knowing what you should be looking for. Recently, there's been a larger interest in non-targeted MS, which allows you to look at unknown identifications. Going with that is the use of the new proposed method EPA 1621, which is a total absorbable organic fluorine method. That's just looking at trying to capture all the organic flora in the new method, and when they try and close this mass balance between the targeted techniques, the non-targeted, and EPA 1621, that's when you see that there is still a lot of research to be done to find out what the most important fluorinated compounds in the environment are because there's still a lot out there.