Increased risk of cancer among firefighters

Firefighters in Norway are at increased risk of some cancers, a new study shows. The findings suggest that risk may be related to occupational exposures.

In a new study of 3881 firefighters in Norway who worked between 1913 and 2018, we found an increased risk of cancers of the urinary tract, throat and peritoneum compared to the general population.

The study is part of a larger project on health risks and health effects of firefighting (HERO). The study is led by Sintef, with the National Institute of Occupational Health (STAMI), the Cancer Registry of Norway and RISE Fire Research as partners. Niki Marjerrison, PhD candidate at the Cancer Registry of Norway, is the lead author of the article now published in the Scandinavian Journal of Work, Environment and Health.

The article describes the first results from the newly established cohort, which includes all employees at 15 fire departments in Norway. Here most areas of the Norway are represented, including the largest cities.

Firefighters are exposed to many known and possible carcinogens in wildfire smoke. This includes, among other things, PAHs (polycyclic aromatic hydrocarbons), asbestos, various organic solvents and diesel exhaust that can be absorbed either via the respiratory tract or the skin.

This first study focused on cancers with a known association with the carcinogenic exposures that occur in firefighting.

Among those who have worked for over 30 years and those who were employed over 40 years ago, the risk of both laryngeal cancer and breast cancer is more than twice as high compared to the general population.

Better prospects for newer firefighters

Among those who have started working as firefighters more recently, no such increased risk was seen.

"One explanation for this may be that exposures in recent times have become lower through better quality and better routines for the use of protective equipment. However, a more certain answer to this question requires that we follow up cancer incidence in this group over a longer period of time, because cancer most often occurs several years after the impact has occurred," says Marjerrison, PhD candidate at the Cancer Registry.

The way forward

Unfortunately, we do not have the information about lifestyle, for example, about cigarette smoking. Firefighters need to be in good shape to do their work, and if they smoke less than the general population, it can camouflage some of the increased cancer risk, for example of lung cancer. Nor do we have historical measurements of substances in fires or detailed information about individual call-outs.

We are currently working on creating indicators for exposure for the individual based on fire statistics from the municipalities, individual work history and information about working conditions at the fire services. Then we will be able to compare low- and high-exposure firefighters in the cohort to look more closely at possible work-related cancer risk.

The study is part of the project Cancer risk among firefighters. Project leader is Kristina Kjærheim, researcher at the Cancer Registry. Read more about the project here.