PFAS analytical standards: A Barrier to Scientific Research?

Per- and polyfluoroalkyl substances (PFAS) have earned the nickname “forever chemicals” due to their persistence in the environment and potential adverse impacts on human health. Yet despite the urgent need to monitor and regulate these substances, a critical roadblock remains: restricted access to high‐quality analytical reference standards.

📏 Why Are Reference Standards Essential?

Analytical reference standards are high-purity substances that serve as benchmarks in chemical analysis. For PFAS research, they are crucial for:

✅ Accurate detection and quantification of PFAS in environmental and biological samples
✅ Ensuring reproducibility and comparability of scientific results
✅ Supporting toxicological studies for effective health and environmental regulations

Yet, out of 15,000+ known PFAS, only about 100 can currently be measured due to the limited availability of reference standards

The Challenge: Restricted Access to PFAS Standards ⚠️

In a recent article in Environmental Health Perspectives, researchers Xenia Trier (University of Copenhagen) and Stefan van Leeuwen (Wageningen Food Safety Research) highlighted a major stumbling block in PFAS studies: manufacturers are increasingly restricting access to essential reference standards. By citing patent rights and even threatening legal action, some companies have effectively limited the distribution of these standards to the scientific community.

This restricted access means that without pure, certified standards, laboratories struggle to:

• Accurately measure human and environmental exposure
• Ensure reproducibility and comparability of analytical results
• Build a comprehensive understanding of the toxicological profiles of PFAS

Impact on Research and Public Health

The absence of accessible analytical standards has profound implications for both scientific research and public health. For instance:

• Underestimation of Exposure:
  An earlier study by Nadine Kotlarz and colleagues at North Carolina State University demonstrated that PFAS concentrations in human blood were underestimated by a factor of 30 due to the lack of a pure reference standard available at the time.

• Hindered Toxicological Studies:
  Without accurate measurements, toxicologists are forced to rely on incomplete or indirect data, which delays crucial regulatory decisions aimed at protecting communities and ecosystems.

• Delayed Regulatory Action:
  Regulatory agencies depend on robust scientific evidence to set health-based limits. Restricted access to standards slows down this process, leaving potentially harmful exposures unaddressed.

Industry and Regulatory Implications

The limitations imposed by restricted access to PFAS reference standards do not only affect researchers. They also create significant challenges for the entire regulatory framework:

• Incomplete PFAS Inventories:
  With only a small subset of PFAS being quantifiable, environmental assessments risk missing critical data that could reveal higher levels of contamination.

• Call for Reform:
  Many experts are now urging regulatory bodies to mandate that manufacturers supply reference standards for every PFAS compound on the market. Such a measure would enhance transparency, improve risk assessments, and ultimately protect public health.

🧐 Alternative Approaches: Overcoming the Barrier 🔍

While the ideal solution is improved access to authentic analytical standards, alternative methods are emerging:

• Fluorine-19 NMR Spectroscopy:
  This technique, provided within the CASC4DE’s services, offers a promising workaround by quantifying total PFAS without needing a unique standard for every compound. Although its sensitivity is lower than that of liquid chromatography–mass spectrometry (LC-MS/MS), fluorine NMR can provide complementary data that is particularly valuable for detecting groups of PFAS and ultrashort-chain compounds.

• Combined Analytical Workflows:
  Researchers are exploring multi-method approaches—combining targeted LC-MS/MS analyses with total organofluorine measurements—to achieve a more comprehensive picture of PFAS contamination.

Looking Ahead

The restrictions imposed on analytical reference standards are not merely a technical inconvenience; they represent a significant barrier to advancing our understanding of PFAS contamination and its impacts. The scientific community, regulatory agencies, and industry stakeholders must collaborate to ensure that reference standards are made widely available. Such efforts are crucial for accelerating research, refining risk assessments, and ultimately implementing more effective regulations to safeguard human health and the environment.

Conclusion

Restricted access to PFAS reference standards hampers the ability of researchers to quantify these “forever chemicals” accurately. As studies continue to reveal that PFAS exposure may be grossly underestimated, there is an urgent need for reform. By demanding that manufacturers provide reference standards and exploring complementary analytical techniques, we can overcome this barrier and move toward more effective environmental protection and public health policies.