Cancer incidence among firefighters: 45 years of follow-up in five Nordic countries
- Eero Pukkala1,2,
- Jan Ivar Martinsen3,
- Elisabete Weiderpass3,4,5,6,
- Kristina Kjaerheim3,
- Elsebeth Lynge7,
- Laufey Tryggvadottir8,9,
- Pär Sparén4,
- Paul A Demers10
- 1Finnish Cancer Registry, Institute for Statistical and Epidemiological Cancer Research, Helsinki, Finland
- 2School of Health Sciences, University of Tampere, Tampere, Finland
- 3Cancer Registry of Norway, Oslo, Norway
- 4Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- 5Samfundet Folkhälsan Research Center, Samfundet Folkhälsan, Helsinki, Finland
- 6Department of Community Medicine, Faculty of Health Sciences, University of Tromso - The Arctic University of Norway, Tromso, Norway
- 7University of Copenhagen, Copenhagen, Denmark
- 8Icelandic Cancer Registry, Icelandic Cancer Society, Reykjavik, Iceland
- 9Faculty of Medicine, University of Iceland, Reykjavik, Iceland
- 10Occupational Cancer Research Centre, Cancer Care Ontario, Toronto, Ontario, Canada
- Correspondence to Professor Eero Pukkala, Finnish Cancer Registry, Institute for Statistical and Epidemiological Cancer Research, Pieni Roobertinkatu 9, Helsinki FI-00130, Finland;
- Received 18 August 2013
- Revised 2 January 2014
- Accepted 13 January 2014
- Published Online First 6 February 2014
Objectives Firefighters are potentially exposed to a wide range of known and suspected carcinogens through their work. The objectives of this study were to examine the patterns of cancer among Nordic firefighters, and to compare them with the results from previous studies.
Methods Data for this study were drawn from a linkage between the census data for 15 million people from the five Nordic countries and their cancer registries for the period 1961–2005. SIR analyses were conducted with the cancer incidence rates for the entire national study populations used as reference rates.
Results A total of 16 422 male firefighters were included in the final cohort. A moderate excess risk was seen for all cancer sites combined, (SIR=1.06, 95% CI 1.02 to 1.11). There were statistically significant excesses in the age category of 30–49 years in prostate cancer (SIR=2.59, 95% CI 1.34 to 4.52) and skin melanoma (SIR=1.62, 95% CI 1.14 to 2.23), while there was almost no excess in the older ages. By contrast, an increased risk, mainly in ages of 70 years and higher, was observed for non-melanoma skin cancer (SIR=1.40, 95% CI 1.10 to 1.76), multiple myeloma (SIR=1.69, 95% CI 1.08 to 2.51), adenocarcinoma of the lung (SIR=1.90, 95% CI 1.34 to 2.62), and mesothelioma (SIR=2.59, 95% CI 1.24 to 4.77). By contrast with earlier studies, the incidence of testicular cancer was decreased (SIR=0.51, 95% CI 0.23 to 0.98).
Conclusions Some of these associations have been observed previously, and potential exposure to polycyclic aromatic hydrocarbons, asbestos and shift work involving disruption of circadian rhythms may partly explain these results.