PFAS 'Forever Chemicals': Why Newer Variants Are Missing in Whale Tissue Studies

Study Reveals Gap in PFAS Tracking in Marine Life

Researchers in the Faroe Islands have been collecting tissue samples from North Atlantic long-finned pilot whales since the 1980s. These samples, archived over decades, have helped scientists track the presence of human-made contaminants in remote marine environments.

Jennifer Sun, a researcher at Harvard University studying PFAS—per- and polyfluoroalkyl substances, often called 'forever chemicals'—led a recent study analyzing PFAS accumulation in pilot whale tissue over the past 20 years. The findings revealed an unexpected pattern: while older PFAS concentrations decreased as expected, newer PFAS chemicals were largely absent from the samples.

Using tissue collected between 2001 and 2023, Sun and her team measured bulk extractable organofluorine, which indicates the total amount of organofluorine-containing chemicals (including PFAS) in the tissue. They then identified 28 specific PFAS chemicals out of thousands of possible formulations. The results showed a decline in legacy PFAS but no significant presence of newer PFAS variants.

This discrepancy raises a critical question in PFAS research: Where are these newer PFAS accumulating?

The Rise of Novel PFAS and Regulatory Challenges

PFAS are divided into two main categories: legacy PFAS and novel PFAS. Legacy PFAS, such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), were widely produced from the 1970s to the 1990s for use in nonstick cookware, food packaging, waterproof fabrics, industrial manufacturing, and firefighting. These were phased out in the early 2000s due to their environmental persistence and health risks.

Novel PFAS emerged as replacements, often designed with shorter fluorinated carbon chains to reduce environmental persistence. However, their production and use have surged globally, with potentially millions of different chemical structures in circulation. Unlike legacy PFAS, novel PFAS are not yet subject to the same regulatory scrutiny, allowing companies to introduce new formulations with limited oversight.

Why Are Newer PFAS Missing in Whale Tissue?

The absence of newer PFAS in the whale tissue samples suggests these chemicals may be accumulating in other environmental compartments or organisms not yet studied. Regulatory frameworks in the U.S. and elsewhere typically target specific PFAS chemicals, requiring individual testing for each new formulation before restrictions are imposed. This piecemeal approach struggles to keep pace with the rapid proliferation of novel PFAS, many of which environmental advocates refer to as 'regrettable substitutions' due to their potential harmful effects.

Sun and her colleagues emphasize the urgent need for broader research to understand the fate and transport of these emerging chemicals. With millions of potential PFAS formulations and behaviors, the risks to human health and the environment remain poorly understood.

Implications for Human and Environmental Health

The study underscores the challenges of tracking and regulating PFAS, particularly as manufacturers continue to develop new variants. The lack of comprehensive data on novel PFAS raises concerns about their long-term impact on ecosystems and human exposure pathways.

As researchers work to fill these knowledge gaps, the findings highlight the need for more robust monitoring and regulatory strategies to address the growing threat posed by PFAS pollution worldwide.