Exposure to certain chemicals while on the job may increase the risk of prostate cancer among firefighters, according to a recent study published by Quaid et al in Environmental and Molecular Mutagenesis.
Background
Prostate cancer has the highest incidence of any cancer type among U.S. male patients. The incidence of prostate cancer is 1.21 times higher among firefighters compared with the general population as a result of work-related chemical exposures, including smoke and firefighting foam.
Some of these chemicals can affect how genes are expressed through a process of epigenetic modification, and certain modifications—including DNA methylation—may contribute to cancer development. One class of chemicals that has been correlated with epigenetic modifications is per- and polyfluoroalkyl substances (PFAS)—which are present in firefighting foam as well as many household items like nonstick pans and water-resistant clothing.
Study Methods and Results
In the recent study, the investigators analyzed the methylation of genes from firefighters.
They found evidence that experienced firefighters had different epigenetic modifications at chromosome 8q24 compared with new firefighters. This region has been linked to the risk of prostate cancer.
The investigators then evaluated whether there was a link between exposure to PFAS and epigenetic modifications. They discovered that in many fire departments, experienced and new firefighters had similar exposure to PFAS. However, exposure to the PFAS chemical branched perfluorooctanoic acid was linked to epigenetic modifications.
Conclusions
“With these published findings, we have clear evidence of the health risks that firefighters face due to cumulative exposure on the job,” emphasized senior study author Jeff Burgess, MD, MPH, Professor, Director of the Center for Firefighter Health Collaborative Research, and a member of the BIO5 Institute at the University of Arizona Mel and Enid Zuckerman College of Public Health. “This study demonstrates the power of the Fire Fighter Cancer Cohort Study to combine data across grants—in this case, awards from the Federal Emergency Management Agency in 2014, 2015, and 2018—to more powerfully evaluate questions from the fire service, this time around exposures and increased prostate cancer risk,” he concluded.
Disclosure: The research in this study was supported in part by the National Institute of Environmental Health Sciences of the National Institutes of Health, the Federal Emergency Management Agency, and the U.S. Centers for Disease Control and Prevention. For full disclosures of the study authors, visit onlinelibrary.wiley.com.
