A new study uncovered an association between exposure to chemicals commonly used in firefighting and glioma risk, reinforcing earlier research that has suggested a link between firefighting and the development of cancers.

The small study led by Dr. Elizabeth B. Claus, a professor at the Yale School of Public Health, member of Yale Cancer Center, and founder of the International Low Grade Glioma Registry, showed that the glioma tumors of some firefighters had a distinctive genetic pattern or “mutational signature.” Those specific signatures were previously shown to be caused by exposure to chemicals called haloalkanes, which are associated with flame retardants, fire extinguishants, and propellants. The study results were published March 10 in Cancer, a peer-reviewed journal of the American Cancer Society.

“Although glioma is largely associated with mutational processes that correlate with age, our finding that some gliomas have tumor signatures associated with environmental agents, such as haloalkanes, is of great interest given the lack of risk factors previously identified for glioma development,” said Dr. Claus.

The study included 35 participants from the University of California San Francisco Adult Glioma Study. The glioma tumors from 17 individuals (with an average fire-fighting history of 22 years) were compared with those from 18 individuals in non-firefighting occupations. The comparison showed an increased presence of haloalkane-associated mutational signatures in the fire-fighters’ tumors. Interestingly, several non-firefighters who were in occupations likely to expose them to haloalkanes (shipyard workers, painters) also showed evidence of the haloalkane signature in their gliomas.

“Although intriguing, our study is small and will require confirmation in larger samples,” said Dr. Claus. “It will also be of interest to explore whether these tumor patterns are seen in other types of cancers in fire-fighters as well as in persons who may have high exposure to haloalkanes by virtue of their occupation or environment. Identification of exposure risk would be helpful in developing preventive measures.”

Dr. Claus collaborated with researchers from Emmanuel College, the University of California San Francisco, Brigham and Women’s Hospital, and the University of Southern California. Joining Dr. Claus was first author Vincent L. Cannataro, a former postdoctoral fellow at Yale, as well as co-authors Paige M. Bracci, Jennie W. Taylor, Lucie McCoy, Terri Rice, Helen M. Hansen, Anne E. Heffernan, Joseph Wiemels, John Wiencke, and Margaret Wrensch.

The research was supported by the National Institutes of Health under award numbers 5U2C-CA252979, P50CA097257, and R01CA52689. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.