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Friday 1 July 2022

Firefighting shown to be carcinogenic

Occupational exposure as a firefighter has been classified as carcinogenic to humans by IARC, the leading global cancer authority

  • Anna Stec, the University of Central Lancashire’s Professor of Fire Chemistry and Toxicity, is one of 25 leading scientists from eight countries who discussed the carcinogenic risks to firefighters at the International Agency for Research on Cancer (IARC)
  • Occupational exposure as a firefighter was classified as “carcinogenic to humans” on the basis of “sufficient” evidence for cancer in humans
  • There was “sufficient” evidence of carcinogenicity in humans for mesothelioma and cancer of the bladder and “limited” evidence for cancers of the colon, prostate, and testis, and for melanoma and non-Hodgkin lymphoma.

From 7-14 June 2022, 25 scientists from eight countries met under a strict protocol at the International Agency for Research on Cancer (IARC) in Lyon, France, to finalise their evaluation of the carcinogenicity of occupational exposure as a firefighter.

Published in the Lancet today, the group has found that occupational exposure as a firefighter is “carcinogenic to humans” (Class 1). The previous assessment, in 2007, had classified firefighting as “possibly carcinogenic” (Class 2b). The IARC Monographs identify preventable causes of human cancer. This classification can be applied to all types of firefighters, and also to both men and women.

"As one of the 25 contributory researchers to the IACR statement, our research found that firefighters are frequently exposed to carcinogens that can have a serious impact on their health."

UCLan’s Professor of Fire Chemistry and Toxicity Anna Stec

The types of fires, building materials, personal protective equipment (PPE), and roles and responsibilities of firefighters have changed substantially over time. As an example, the increase of wildland fires in urban areas has changed the types of exposure that firefighters face.

Since the previous classification of firefighting in Group 2b by the IARC Monograph in 2007, many new studies have investigated the association between occupational exposure as a firefighter and cancer risk in humans. The 25 scientists discussed these studies, which included a total of 52 cohort and case-control studies, 12 case reports, and 7 meta-analyses.

The working group identified in the human cancer evidence a causal positive association between occupational exposure as a firefighter and mesothelioma and cancer of the bladder. Positive associations were also observed for cancers of the colon, prostate, and testis, and for melanoma and non-Hodgkin lymphoma, although other explanations for these findings could not be ruled out with reasonable confidence.

UCLan’s Professor of Fire Chemistry and Toxicity Anna Stec, a member of the IARC committee, said: “As one of the 25 contributory researchers to the IACR statement, our research found that firefighters are frequently exposed to carcinogens that can have a serious impact on their health. In addition to fires and smoke, we have found high levels of cancer-causing substances (carcinogens) in fire engines, fire stations and personal protective equipment. In response, we developed our Firefighters Cancer and Disease Registry and Best Practice Report which are already in use in four countries, including the UK. Following this guidance, we hope that steps will be taken to keep firefighters safe and reduce the occurrence of cancer and other diseases within this lifesaving profession.

“Members of parliament must call for an urgent debate on firefighters’ health and cancer so that we can appropriately support those who work to save our lives.”