Demystifying PFAS Testing

Per- and Polyfluorinated Alkyl substances (PFAS) are global contaminants that do not readily biodegrade, hence them also being known as "forever chemicals." These industrial and commercial compounds are also ubiquitous – they are routinely found in the environment across the globe, which is a major cause for concern as they have potential health implications, including an impact on the effectiveness of the human immune system.

While many of the health effects of PFAS are still being studied, we know PFAS bind to proteins in exposed organisms and are resistant to metabolic biodegradation and excretion. They also biomagnify – they increase in concentration in the tissues of organisms as they progress up the food chain, before arriving on our plates. There are, however, other sources of PFAS, including medical devices, consumer products, food packaging and kitchenware. 

A growing awareness of the risks of persistent organic pollutants recently saw the U.S. Environmental Protection Agency (EPA) regulate five PFAs in drinking water federally, the first chemicals regulated in 20+ years. They also proposed that nine PFAS be categorized as hazardous to human health under the Resource Conservation and Recovery Act (RCRA). And in January of this year the European Environmental Bureau (EEB), in partnership with ChemSec, tested a group of European politicians for PFAS contamination. Five exceeded existing levels of concern. The overall results mirror the average levels of exposure across the continent, according to the EEB.

As a result, there’s a growing call for testing for the presence of PFAS so their occurrence can be better understood, but what should labs consider before entering this market? The first step is to define your goals. 

If you're a contract testing lab, you need to determine what matrices you’re going to test PFAS, and to what levels. You also need to determine what regulatory or testing methods you need to follow along with any compliance and accreditation needs.

If you're an industrial manufacturer, you probably need to conduct testing to meet some regulatory guidance or discharge permits, whether that's for your raw materials or waste discharge. 

If you’re a regulator trying to identify new PFAS compounds, you might need to investigate what tools you’ll need to discover currently unknown PFAS. 

If you are an engineering firm or remediation company, you need to identify if the treatment is removing PFAS but also to ensure you are not creating or converting them into other by-products.

Analytical considerations
 

Effective PFAS testing relies on thorough sample preparation and precise analysis. Depending on the sample matrix and relevant regulations, an enrichment and/or cleanup step may be necessary before sample analysis. 

Sample preparation is essential for isolating PFAS from diverse matrices like drinking water, soil, and air. Specific procedures can remove interfering substances from samples, ensuring high purity and minimizing background noise in PFAS analysis. Enrichment techniques further optimize detection limits, enhancing recovery from challenging environmental samples.

On the analytical front, in targeted PFAS analysis, LC triple quadrupoles are commonly used due to their exceptional sensitivity and selectivity. However, these instruments are restricted to compounds for which an analytical standard exists and to relatively polar compounds that ionize well in LC/MS. For non-polar & volatile PFAS, GC/MS can be the preferred technique. Additionally, for non-targeted analysis of huge amounts of yet unknown PFAS high resolution LC/MS instruments such as the LC/Q-TOF are increasingly more popular. With each of these techniques, the software to analyse and report the data is also critical and needs to be able to perform according to compliance and accreditation requirements. 

Given PFAS compounds’ surface-active properties, proper sample preservation and secure transportation methods are critical. These properties can lead to adherence to sample vessels during transit and storage, potentially compromising sample integrity. Therefore, using airtight containers designed to minimize surface interactions and contamination is essential. Opting for PFAS-free materials for sample storage to prevent unwanted chemical interactions that could compromise analytical results.

Regulatory trends on the horizon
 

Several regulatory trends are emerging globally that companies should be aware of. One significant trend is the establishment of stricter drinking water standards. The US EPA has recently set the first-ever national, legally enforceable drinking water standards for certain PFAS. This trend is expected to continue, with more stringent limits being set for various additional PFAS compounds in drinking water. 

Another trend is the comprehensive bans and restrictions being considered by the European Union, which aims to phase out at least 10,000 PFAS chemicals by 2030. This broad approach is intended to manage the risk from this class of substances more effectively than regulating individual compounds. 

Additionally, both the US and EU are enhancing reporting and recordkeeping requirements for PFAS especially from manufacturers and industry. For example, the US EPA has finalized new PFAS reporting rules under the Toxic Substances Control Act (TSCA). 

There is also a growing movement towards global harmonization of PFAS regulations. Countries are increasingly aligning their regulatory frameworks with international standards, such as those set by the Stockholm and Rotterdam Conventions. These trends highlight the importance of staying informed and compliant with evolving regulations to effectively manage PFAS-related risks.

Staying current with PFAS regulations is crucial for ensuring compliance and maintaining high standards in environmental testing. To stay in touch with changes, it is important to regularly participate in meetings, webinars, and conferences hosted by regulatory agencies such as the US EPA, European Chemicals Agency (ECHA), and other global bodies. This engagement provides firsthand updates on regulatory changes and emerging trends. 

Additionally, subscribing to newsletters from reputable sources like the Environmental Protection Agency, Environmental Law Institute, and industry-specific publications can highlight recent regulatory updates and provide expert analysis. Joining professional organizations such as the American Chemical Society (ACS) or the Society of Environmental Toxicology and Chemistry (SETAC) offers access to exclusive resources, including regulatory updates, research findings, and networking opportunities. Utilizing online databases and tools that track regulatory changes, such as the OECD Global Database of PFAS and the CompTox Chemicals Dashboard, can also provide comprehensive information on PFAS regulations, toxicology and occurrence data. Finally, establishing connections with other professionals in the field and sharing insights and experiences can help you stay informed about regulatory changes and best practices.

Instrument suppliers play an important role too. For example, Agilent works with organizations such as the US EPA and other regulatory and consensus standard bodies worldwide, and participates in committees, conferences, and seminars.

Regulation changes drive the need for more comprehensive and frequent testing. As policies and rules expand to cover a broader range of materials and products, including food, water, and consumer goods, there is a growing demand for enhanced and sophisticated test methods. Laboratories must expand their testing capacities, acquire new technologies, and stay updated with the latest analytical techniques and methods in order to meet this demand.

Managing increased testing capacity requires careful planning. High standards of quality control, well-trained laboratory personnel, data-management and robust procedures are essential to handle the higher volume of samples without compromising accuracy and reliability.