Firefighter mesothelioma rates are twice that of the rest of the population according to a dramatic new study – the first ever of its kind.
The researchers said it was likely that the findings were associated with exposure to asbestos, and noted that this is the first study ever to identify higher rates of mesothelioma in U.S. firefighters.
What also makes the study important is that it analyzed cancers and cancer deaths through 2009 among 29,993 firefighters from the Chicago, Philadelphia, and San Francisco fire departments who were employed since 1950. The large number of study subjects and the many years that they were tracked elevates the credibility and importance of the study; especially in light of the grim results.
The findings are consistent with earlier studies, but because this one followed a larger study population for a longer period of time, the results strengthen the scientific evidence for a relation between firefighting and cancer, the researchers said.
The National Institute for Occupational Safety and Health (NIOSH) led the study in collaboration with the National Cancer Institute and the University of California Davis. The results from the NIOSH researchers and their colleagues were reported on October 14 in the online edition of the international medical journal Occupational and Environmental Medicine, an offshoot of the cutting edge British Medical Journal.
Other types of cancer were also found to be elevated in this study of firefighters in the three U.S. cities. The researchers found that rates of cancers of the respiratory, digestive, and urinary systems were higher in the firefighters than in the U.S. population as a whole.
Firefighters can be exposed to contaminants from fires that are known or suspected to cause cancer. These contaminants include combustion byproducts such as benzene and formaldehyde, and materials in debris such as asbestos from older structures. These materials may be inert under normal conditions but break down and are released when structures collapse during a fire.
The findings of the new study do not address other cancer risk factors, such as smoking, diet and alcohol consumption, NIOSH pointed out, according to an article in EHS Today, an occupational health and safety magazine.
A second phase of the study is planned and will further examine employment records from the three fire departments to gain more insight into occupational exposures, and to look at exposures in relation to cancer incidence and mortality, NIOSH said.