Do firefighters have an increased risk of glioma?
Researchers have demonstrated a link between a distinct glioma mutational signature and occupational exposure to haloalkanes.
In a collaborative study, led by Elizabeth Claus from Yale School of Public Health (CT, USA), researchers demonstrated a link between exposure to chemicals used in firefighting and glioma risk. Being aware of this link could help with identifying occupational risks associated with gliomas and developing measures to prevent them.
Glioma, a malignant primary brain tumor, is most commonly linked to age and endogenous mutational process relating to age. However, some gliomas have distinct mutational signatures – single base substation signature 42 – that have previously been linked to exposure to haloalkanes.
Haloalkanes are chemical compounds widely used in fire extinguishants, flame retardants, pesticides and other products. Identifying exogenous mutational process in cancers, such as exposure to haloalkanes, is important as it may help with the development of preventative measures and strategies to reduce mutagenesis.
“As firefighters have exposure to such chemical agents, we examined mutational signatures in glioma brain tumors diagnosed in persons who worked as firefighters versus those who did not,” explained study lead Elizabeth Claus.
The researchers compared the mutational signatures of 35 glioma patients from the University of California Adult Glioma Study. Overall, 17 of the patients had an occupational history of firefighting for an average of 22 years, while the other 18 glioma patients did not. The comparison revealed an increased presence of haloalkane-associated mutational signatures in the tumors of ex-firefighters compared to non-firefighters.
Interestingly, the haloalkane-associated mutational signature was also seen in some patients who did not have a firefighting occupation but still had exposure to haloalkanes through other occupations such as painters and shipyard workers.
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“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,” commented Claus.
Although this study was small, it provides preliminary data on occupational exposure to haloalkanes and glioma risk. Larger studies will be required for confirmation of this link and to determine necessary preventative measures. “Identifying exposure to such mutational agents is important to inform public health intervention strategies and pinpoint occupational hazards that may be avoidable,” concluded Claus.