A groundbreaking study spearheaded by researchers from the University of Arizona Health Sciences recently unveiled compelling insights into occupational exposure to per- and polyfluoroalkyl substances (PFAS) among frontline workers in Arizona. Published in the prestigious Journal of Exposure Science & Environmental Epidemiology, this research sheds new light on the differential serum concentrations of PFAS chemicals across various professions, notably firefighters and health care workers, emphasizing the urgent need to understand and mitigate PFAS exposure in occupational settings.
PFAS are a complex group of synthetic chemicals recognized for their remarkable stain-, water-, and flame-resistant properties, making them indispensable in numerous industrial and consumer applications. Their molecular structure confers an exceptional environmental stability; PFAS do not readily break down under natural conditions, resulting in their infamous nickname, “forever chemicals.” This stability, while beneficial commercially, poses significant environmental and public health challenges due to their persistence and bioaccumulation potential in human tissues.
The study meticulously analyzed blood samples from a robust cohort of 1,960 participants, encompassing 280 firefighters, 787 health care workers, and 734 other essential workers, collected over nearly three years from July 2020 to April 2023. This timeline allowed the researchers to observe trends in PFAS serum levels and provided an unprecedented longitudinal perspective on how PFAS body burdens vary among occupational groups with diverse exposure risks.
Firefighters emerged as the group with the highest detected concentrations of specific PFAS compounds, particularly PFHxS, Sm-PFOS, n-PFOS, and PFHpS. These elevated levels affirm previous findings and underscore the unique exposure pathways faced by firefighters, primarily linked to their use of PFAS-laden protective gear and aqueous film-forming foams (AFFF) employed during firefighting operations. The robust accumulation of PFAS in firefighter serum reveals the insidious nature of occupational hazards inherent in firefighting and points to critical intervention areas.
Health care workers, although less studied historically concerning PFAS exposure, demonstrated moderate elevations in PFHpS and PFUnA. More strikingly, they exhibited significantly higher odds of harboring Sb-PFOA and PFDoA compounds compared to other essential workers. These findings potentially implicate medical-grade materials such as single-use surgical masks, disposable gowns, and certain X-ray films as inadvertent yet tangible PFAS sources within health care environments—highlighting an uncharted exposure pathway that necessitates urgent investigation.
Across the broader workforce categorized as other essential workers, PFAS serum concentrations were noted to decline between 6% and 17% annually throughout the study period. Despite this encouraging trend, the persistent presence of detectable PFAS levels within this group signals ongoing environmental or occupational exposures that must not be overlooked. This decline could partly reflect regulatory actions limiting PFAS use, but sustained vigilance and improved surveillance remain crucial.
The multidisciplinary research team boasts an impressive roster of experts, including senior author Dr. Kate Ellingson, an epidemiologist at the Mel and Enid Zuckerman College of Public Health, and co-author Dr. Jeff Burgess, director of the Center for Firefighter Health Collaborative Research. Their combined expertise in environmental epidemiology and occupational health underpins the study’s methodological rigor and elevates its relevance to public health policy and intervention frameworks.
Importantly, the methodology leveraged the Arizona Healthcare, Emergency Response, and Other Essential Worker Surveillance Study (AZ HEROES), an innovative surveillance platform designed to capture nuanced exposure data across diverse frontline professions. Such infrastructure allows researchers to contextualize PFAS exposure levels with detailed occupational histories and behavioral factors, providing a comprehensive lens on risk stratification.
From a toxicological perspective, PFAS exposure has been correlated with an array of adverse health outcomes, ranging from elevated cholesterol levels, immunotoxicity including diminished vaccine response, to increased cancer risks and reproductive health challenges. By delineating occupation-specific PFAS body burdens, this study paves the way for targeted protective measures, regulatory scrutiny, and worker education to abate these health risks.
Firefighters’ historically high PFAS exposures underscore the critical need to reevaluate current personal protective equipment (PPE) materials and fire suppressants. This emerging evidence advocates for accelerated development and deployment of PFAS-free alternatives, alongside rigorous decontamination protocols, to curtail ongoing occupational exposure that can translate into chronic health detriments.
Conversely, the revelation of health care workers’ PFAS exposure prompts a reevaluation of medical supply chains and sterilization processes. As health care environments rely heavily on disposable protective gear and diagnostic materials, identifying and mitigating PFAS sources could be transformative for safeguarding millions of workers and patients alike.
Finally, this pivotal study calls for an expansion of epidemiologic surveillance beyond traditionally studied groups and fosters interdisciplinary collaboration between chemists, epidemiologists, industrial hygienists, and policy makers. Addressing the challenges posed by PFAS exposure demands a multifaceted approach—combining exposure science, toxicology, occupational health, and environmental regulation—to curtail the long-term public health impact of these ubiquitous chemicals.
As the scientific and regulatory communities grapple with the complexities of PFAS, studies like this illuminate the silent occupational hazards faced by essential workers, bringing clarity to exposure patterns and galvanizing action to create safer workplaces and healthier communities in the face of persistent chemical threats.
Subject of Research: People
Article Title: Differences in serum concentrations of per-and polyfluoroalkyl substances by occupation among firefighters, other first responders, healthcare workers, and other essential workers in Arizona, 2020–2023
News Publication Date: 6-Mar-2025
Web References:
References:
- Ellingson, K. et al. (2025). Differences in serum concentrations of per- and polyfluoroalkyl substances by occupation among firefighters, other first responders, healthcare workers, and other essential workers in Arizona, 2020–2023. Journal of Exposure Science & Environmental Epidemiology. DOI: 10.1038/s41370-025-00753-7.
Keywords:
Carcinogenesis, Environmental methods, Cancer, Forest fires, Public policy, Environmental chemistry
