International Archives of Occupational and Environmental Health (2018) 91:759–766
Mortality in a cohort of Danish ﬁreﬁghters; 1970–2014
Kajsa Ugelvig Petersen
· Julie Elbæk Pedersen
· Jens Peter Bonde
· Niels Erik Ebbehøj
· Johnni Hansen
Received: 27 September 2017 / Accepted: 22 May 2018 / Published online: 28 May 2018
© Springer-Verlag GmbH Germany, part of Springer Nature 2018
Purpose Occupational exposure of ﬁreﬁghters involves a complex range of potential health threats from toxic chemicals,
shift work, extreme heat, physical and emotional strain. The aim of this study is to examine overall and disease-speciﬁc
mortality among Danish ﬁreﬁghters.
Methods Through systematic collection of personnel and membership records from employers and trade unions, past and
present male Danish ﬁreﬁghters were identiﬁed (n = 11,775). Using the unique Danish personal identiﬁcation number,
information on additional employment, vital status and cause of death was linked to each member of the cohort from the
Supplementary Pension Fund Register, the Danish Civil Registration System and the Danish Register of Causes of Death.
Standardized mortality ratios (SMRs) were calculated for speciﬁc causes of death using rates for two reference groups, a
random sample of the male working population (n = 262,168) and the military (n = 396,739), respectively.
Results Overall mortality was signiﬁcantly reduced among the ﬁreﬁghters compared to both the sample of the working
population and the military (SMR 0.74, 95% CI 0.69–0.78 and SMR 0.88, 95% CI 0.83–0.93). Further, the SMRs for endo-
crine diseases, mental disorders, non-traﬃc related accidents and other external causes were signiﬁcantly lower against both
reference groups. Death from stomach cancer was signiﬁcantly increased among the full time ﬁreﬁghters, while part time/
volunteer workers shared a signiﬁcant increase in prostate cancer death compared to both references.
Conclusions Despite potential exposure to several occupational hazards, male Danish ﬁreﬁghters have a lower mortality
than both the Danish working population in general and Danish military employees.
Keywords Fireﬁghter · Mortality · Epidemiology · Occupational exposure
In addition to the apparent imminent dangers arising from
the actual encounter with uncontrolled ﬁres, ﬁreﬁghters are
intermittently exposed to a wide range of potential health
hazards in the form of toxic chemicals, shift work, heat
stress, extreme physical exertion and emotional trauma.
Concerns have thus been raised regarding the resulting
changes in both acute and chronic morbidity among ﬁre-
ﬁghters and ultimately also their mortality.
Many previous studies on mortality among ﬁreﬁghters
around the world have consistently shown either reduced
or even all-cause mortality when compared to correspond-
ing background populations (Ahn and Jeong 2015; Ama-
deo et al. 2015; Daniels et al. 2014; Glass et al. 2016a, b,
2017; Haas et al. 2003; Ide 2014; Ma et al. 2005; Wagner
et al. 2006). However, selection of healthier individuals into
employment may bias results when occupational cohorts are
measured simply against the general public.
This study, therefore, aims to present a more balanced
image of the actual eﬀects of ﬁreﬁghting on multiple aspects
of health analyzing speciﬁc causes of death using both a
random sample of Danish employees and the military as
references. In addition, selected exposure parameters such as
type and duration of ﬁreﬁghting employment will be evalu-
ated regarding impact on patterns of mortality. The unique
Electronic supplementary material The online version of this
article (https ://doi.org/10.1007/s0042 0-018-1323-6) contains
supplementary material, which is available to authorized users.
* Kajsa Ugelvig Petersen
The Danish Cancer Society Research Center, The Danish
Cancer Society, Strandboulevarden 49, 2100 Copenhagen,
Department of Occupational and Environmental Medicine,
Copenhagen University Hospital Bispebjerg, Copenhagen,