An expert panel recently confirmed what has long since been suspected in the mesothelioma community: firefighting is a carcinogenic (cancer-causing) profession, and specifically puts firefighters at risk of mesothelioma, as well as bladder cancer and several other forms of cancer.
The panel was recently convened by the International Agency for Research on Cancer (IARC), which is part of the World Health Organization (WHO), to study the cancer risk of firefighters. Their findings were published in The Lancet Oncology on June 30th, 2022.
The IARC/WHO Panel and What it Found
The IARC panel consisted of 24 scientists, medical professionals, and experts from eight different countries (including four US representatives). It conducted a meta-review of 52 cohort and case-controlled studies and 12 case reports that followed firefighters and their health outcomes in North America, Asia, and Europe.
Their main findings were as follows:
- Firefighters have a 58% higher risk than the general public of developing malignant mesothelioma. This high rate of mesothelioma is likely caused by firefighting in older commercial buildings and homes containing asbestos, specifically from breathing in asbestos fibers from damaged and disturbed asbestos materials. Burning buildings and structures that contain asbestos can release particularly intense and toxic concentrations of asbestos fibers into the air, which are then inhaled by firefighters (especially firefighters without sufficient PPE and protective gear).
- Exposure to airborne asbestos fibers still occurs to a significant extent among firefighters, despite emphasis on protective gear and PPE.
- Diagnosis with mesothelioma often occurs many years—if not multiple decades—after exposure to asbestos fibers. This means that firefighters receiving mesothelioma diagnoses were often exposed many years—often 20-60 years—beforehand.
- Bladder cancer is also a significant risk for firefighters. This is the result of firefighters’ prolonged exposure to certain toxic/carcinogenic chemicals that are commonly released in strong concentrations as structures burn. The body absorbs these carcinogens, transferring them to the blood. They are then filtered out by the kidneys, and turned into urine, which is held in the bladder and then expelled from the body. It was found that greater concentrations of these chemicals in urine can damage the endothelial lining of the bladder, increasing firefighters’ risk of developing a specific type of bladder cancer called Transitional Cell Carcinoma (TCC).
- Additionally, there was evidence of elevated risk for colon, prostate, and testicular cancers, as well as melanoma and non-Hodgkin lymphoma—though lifestyle may influence malignancy more significantly than is the case with mesothelioma or bladder cancer.
- The published findings highlighted several main carcinogenic factors that firefighters regularly encounter (beyond the ordinary dangers of firefighting), through dermal exposure, inhalation, and ingestion. These include:
- Toxic building materials (i.e., asbestos)
- Combustion products from fires (i.e., polycyclic hydrocarbons, volatile organic compounds, and airborne molecules and particulates, including metals)
- Diesel exhaust
- Potentially carcinogenic flame retardants from textiles
- Persistent organic pollutants (i.e., polyfluorinated substances) used in firefighting foams
- Other hazards (i.e., heat stress, sleep disturbance from shift work, ultraviolet and other radiation exposure)
What does this mean for firefighters?
There are over 15 million firefighters around the world, a number that will likely increase as largescale fires become more frequent due to climate change.
Due to the clear and present cancer risk posed to firefighters by their profession, the WHO has reclassified firefighting to Group 1 Status, its highest tier of occupational risk for cancer. All professions with Group 1 Status are considered “definitively carcinogenic to humans.”
This conclusion represents a major shift in IARC/WHO thinking and policy, but only confirms what many firefighters and the medical professionals who treat them (as well as their friends and family members) have suspected for many years from lived experience.
It has been enormously frustrating to the firefighter community that their significantly elevated cancer risk has taken so long to officially confirm. Prior to this confirmation, firefighting was only officially classed as having Group 2b Status (that is, as being “possibly carcinogenic to humans”).
For years, advocacy organizations like the IAFF (International Association of Firefighters) have put in a tremendous amount of effort to get recognition and consensus on the carcinogenic nature of firefighting, so that more steps can be made to lower the risk, protect firefighters, and appropriately compensate and care for them if and when they do get sick.
Firefighter health advocates say that these findings and the raising of firefighting to Group 1 Status—now putting firefighting on par with tobacco and benzene as a definitive carcinogen—has been a long time coming, but finally getting it done is a step in the right direction.
Experts suggest that this reclassification may lead to new laws that protect firefighters from asbestos exposure and make it easier and more accessible for them to file claims and be compensated for cancer-related damages obtained on the job. It may also inspire further medical research on the topic, which firefighter advocates enthusiastically encourage and support.
What does this mean for firefighters affected by the World Trade Center response?
Firefighters and other 9/11 first responders who assisted in the rescue efforts after the World Trade Center attacks were exposed to carcinogenic materials, including asbestos (as well as lead, mercury, benzene, and dioxins, among others). Asbestos fibers were particularly prevalent in the air around Ground Zero, as the World Trade Center—constructed in the 60s—contained a large amount of asbestos that was primarily used as fire-retardant insulation. When the towers were impacted and then fell, asbestos fibers flooded the air in extremely dangerous concentrations.
2021 marked 20 years since September 11th, 2001. Mesothelioma tends to have a rather long latency period (referring to the time it takes for symptoms to develop after exposure). On average, the first symptoms of mesothelioma do not appear until 20 to 30 years after exposure. This means that by the time mesothelioma symptoms appear, the cancer may already be significantly late-stage—often too late for aggressive or effective treatment.
This also means that the first wave of mesothelioma diagnoses among 9/11 first responder firefighters is coming. Indeed, it has already begun: in October 2019, a 52-year-old first responder from Pennsylvania (part of the White Oak Rescue Team) died of mesothelioma. His cancer was linked to asbestos exposure that occurred during his time at Ground Zero.
Any and all firefighters and first responders who were present at Ground Zero should immediately consult their doctors and pursue screenings for mesothelioma as well as other commonly associated cancers and conditions.