nikim

• Babigumira, Ronnie; Veierød, Marit Bragelien; Larsen, Inger Kristin; Berge, Leon Alexander Mclaren; Shala, Nita Kaupang & Marjerrison, Niki [Vis alle 22 forfattere av denne artikkelen] (2025). Benzene exposure and risk of colorectal cancer by anatomical subsite in the Norwegian offshore petroleum workers cohort. Environmental Research. ISSN 0013-9351. 276, s. 1–9. doi: 10.1016/j.envres.2025.121407. Fulltekst i vitenarkiv Vis sammendrag

  Objective: To investigate the association between low levels of benzene exposure (≤0.879 parts per million [ppm]-years) and risk of colorectal cancer (CRC) including its anatomical subsites. Methods: Among 25,347 male workers in the Norwegian Offshore Petroleum Workers (NOPW) cohort with offshore work history (1965–1998), 455 CRC cases were diagnosed 1999–2021. We compared these with a subcohort (n = 2031) drawn from the full cohort. Work histories were linked to a previously developed industry-specific benzene job-exposure matrix (JEM). Cox regression for case-cohort analyses was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for CRC, adjusted for age, body mass index, smoking, alcohol intake, red/processed meat intake, and physical activity. Results: Risks of CRC increased with increasing benzene exposure. For all CRC, the HRs (95% CI) for the most exposed [quartile 4] vs. the unexposed were 1.32 (0.96 to 1.81, [0.177–0.879 ppm-years]; p-trend = 0.085) for cumulative, 1.52 (1.11 to 2.07, [17–34 years]; p-trend = 0.032) for duration, and 1.56 (1.15 to 2.12, [0.015–0.046 ppm]; p-trend = 0.005) for average intensity of benzene exposure. For right-sided colon cancer, the association was most evident for exposure duration (HR = 2.25 (1.33 to 3.80), quartile 4 [17–34 years] vs. unexposed; p-trend = 0.007). Sensitivity analyses showed consistent associations. Conclusion: This study found positive exposure-response associations between low-level benzene exposure and CRC risk in offshore petroleum workers. These findings add to emerging evidence that benzene can be associated with solid tumours including lung and bladder, which potentially has important occupational and public health implications.

• Marjerrison, Niki; Grimsrud, Tom Kristian; Hansen, Johnni; Martinsen, Jan Ivar; Nordby, Karl-Christian & Olsen, Raymond [Vis alle 9 forfattere av denne artikkelen] (2024). Occupational exposures of firefighting and prostate cancer risk in the Norwegian Fire Departments Cohort. Scandinavian Journal of Work, Environment and Health. ISSN 0355-3140. 51(2), s. 100–110. doi: 10.5271/sjweh.4202. Fulltekst i vitenarkiv Vis sammendrag

  Objectives Excess incidence of prostate cancer (PC) is frequently observed among firefighters; however, the association with specific occupational exposures of firefighting, as well as the influence of a medical surveillance bias, remains unclear. Our aim was to study PC risk within a firefighter cohort, applying indicators of exposures. Methods We used indicators of various firefighting exposures to examine PC risk among men in the Norwegian Fire Departments Cohort (N=4251). Incident PC cases, including clinical characteristics, were obtained from the Cancer Registry of Norway (1960–2021). Cox regression was used to estimate hazard ratios (HR) by cumulative exposure in tertiles (reference: lowest) for all, aggressive, and indolent PC, with adjustment for age and birth cohort. The cumulative incidence of PC across birth cohorts and diagnostic periods was examined. Results No clear associations emerged for any of the exposure indicators, although we observed an HR of 1.31 [95% confidence interval (CI) 0.63–2.72] for aggressive PC in the highest tertile of fire exposure score and 1.31 (95% CI 0.60–2.89) for indolent PC in the highest tertile of inhalation score. Assessment of cumulative incidence demonstrated a greater number of diagnoses at younger ages after 1990, particularly for indolent and unclassifiable PC. Conclusions We found little support for an association between firefighting exposures and PC risk. However, our study had few cases in analyses by clinical stage. Challenges in studies of firefighters’ PC risk remain, including difficulties in exposure characterization and the unclear magnitude of a medical surveillance bias.

• Marjerrison, Niki; Grimsrud, Tom Kristian; Hansen, Johnni; Martinsen, Jan Ivar; Nordby, Karl-Christian & Olsen, Raymond [Vis alle 8 forfattere av denne artikkelen] (2023). Occupational exposures of firefighting and urinary tract cancer risk among men in the Norwegian Fire Departments Cohort. Occupational and Environmental Medicine. ISSN 1351-0711. 80(12). doi: 10.1136/oemed-2023-109003. Fulltekst i vitenarkiv Vis sammendrag

  Objectives: Increased risks of bladder cancer and mesothelioma were the strongest evidence for the recent reclassification of firefighting as carcinogenic (Group 1) by the International Agency for Research on Cancer. Our study aim was to develop indicators for specific firefighting exposures and examine associations with urinary tract cancer (UTC), including bladder cancer. Methods: We developed indicators for exposure from employment at a fire department or in firefighting jobs, to fire and smoke, and to diesel exhaust for men in the Norwegian Fire Departments Cohort (n=4250). Incident UTC cases were obtained from the Cancer Registry of Norway (1960–2021). Poisson regression was used to estimate incidence rate ratios (IRR) with cumulative exposures grouped into tertiles (reference: lowest exposed tertile) with 0-year, 10-year and 15-year lagging of exposures. Results: During 125 090 person-years of follow-up, there were 76 cases of UTC. IRRs were mostly non-significantly increased in the middle tertile and at or below 1 in the highest tertile for total duration of employment, number of fires attended and fire exposure score with and without lags. In the middle tertile for diesel exhaust exposure, UTC risk was elevated over twofold with 10-year (IRR 2.27, 95% CI 1.22 to 4.20) and 15- year (2.21, 1.18 to 4.16) lags, and near 1 in the highest tertile. Findings for bladder cancer were similar to those for UTC. Conclusions: Dose-response associations between the exposure indicators and UTC were not observed. Future studies using the indicators with more cases are needed.

• Madar, Ahmed Ali; Kurniasari, Astrid; Marjerrison, Niki & Mdala, Ibrahimu (2023). Breastfeeding and Sleeping Patterns Among 6–12-Month-Old Infants in Norway. Maternal and Child Health Journal. ISSN 1092-7875. doi: 10.1007/s10995-023-03805-2. Fulltekst i vitenarkiv
• Sritharan, Jeavana; Kirkham, Tracy L.; MacLeod, Jill; Marjerrison, Niki; Lau, Ashley & Dakouo, Mamadou [Vis alle 10 forfattere av denne artikkelen] (2022). Cancer risk among firefighters and police in the Ontario workforce. Occupational and Environmental Medicine. ISSN 1351-0711. 79(8), s. 533–539. doi: 10.1136/oemed-2021-108146. Fulltekst i vitenarkiv
• Marjerrison, Niki; Jakobsen, Jarle; Grimsrud, Tom Kristian; Hansen, Johnni; Martinsen, Jan Ivar & Nordby, Karl-Christian [Vis alle 8 forfattere av denne artikkelen] (2022). Cancer incidence in sites potentially related to occupational exposures: 58 years of follow-up of firefighters in the Norwegian Fire Departments Cohort. Scandinavian Journal of Work, Environment and Health. ISSN 0355-3140. 48(3), s. 210–219. doi: 10.5271/sjweh.4009. Fulltekst i vitenarkiv Vis sammendrag

  Objectives Firefighters are exposed to a variety of known and suspected carcinogens through their work. However, the association with cancer risk has limited evidence. We examined cancer incidence among firefighters in the newly established Norwegian Fire Departments Cohort restricted to sites with established associations with carcinogens encountered during firefighting. This included sites within the respiratory, urinary, and lympho-hematopoietic systems, and the skin and all sites combined. Methods Male firefighters (N=3881) in the cohort were linked to the Cancer Registry of Norway for incident cancer cases occurring during the period 1960–2018. We calculated standardized incidence ratios (SIR) with rates for the national male population as reference, and stratified SIR analyses by period of first employment, duration of employment, and time since first employment. Results Elevated risk was seen for all sites combined (SIR 1.15, 95% confidence interval 1.07–1.23). Elevated risk of urinary tract cancer was observed among firefighters who began working before 1950, and with observation ≥40 years since first employment. Risk of mesothelioma and laryngeal cancer were elevated with ≥40 years since first employment and with ≥30 years employment duration. Conclusions The observed associations between firefighting and urinary tract cancer, laryngeal cancer, and mesothelioma have been observed in some studies previously, and our results suggest the observed elevated risks are related to carcinogenic occupational exposures. Differences in risk by period of employment potentially reflect changes in exposures from improved quality and use of personal protective equipment.

• Marjerrison, Niki; Jacobsen, Jarle; Demers, Paul A.; Grimsrud, Tom Kristian; Hansen, Johnni & Martinsen, Jan Ivar [Vis alle 9 forfattere av denne artikkelen] (2022). Comparison of cancer incidence and mortality in the Norwegian Fire Departments Cohort, 1960-2018. Occupational and Environmental Medicine. ISSN 1351-0711. 79, s. 736–743. doi: 10.1136/oemed-2022-108331. Fulltekst i vitenarkiv Vis sammendrag

  Objectives Elevated risk of cancer at several sites has been reported among firefighters, although with mixed findings. The purpose of this study was to calculate standardised incidence ratios (SIRs) and standardised mortality ratios (SMRs) for cancer and compare them to assess whether use of the different measures could be a source of inconsistencies in findings. Methods The Norwegian Fire Departments Cohort, comprising 4295 male employees who worked at 15 fire departments across Norway, was linked to health outcome registries for the period 1960–2018. SIRs and SMRs were derived using national reference rates. Results Overall, we observed elevated incidence of colon cancer (SIR, 95% CI 1.27, 1.01 to 1.58), mesothelioma (2.59, 1.12 to 5.11), prostate cancer (1.18, 1.03 to 1.34) and all sites combined (1.15, 1.08 to 1.23). Smaller, non-significant elevations were found for mortality of colon cancer (SMR, 95% CI 1.20, 0.84 to 1.67) and mesothelioma (1.66, 0.34 to 4.86), while SMR for prostate cancer was at unity. Potential errors were observed in some of the mortality data, notably for mesothelioma cases. Among those who died of cancer, 3.7% (n=14) did not have a prior diagnosis of malignancy at the same site group. Conclusions Assessment of incidence or mortality did not greatly influence the interpretation of results. The most prominent differences in SIR and SMR appeared to be due to inconsistencies between sites of cancer diagnosis and cause of death. The difference in SIR and SMR for prostate cancer suggested a detection bias from differential screening practices.

• Ahmed, Hassan Soheir; Marjerrison, Niki; Kjøllesdal, Marte Karoline Råberg; Stigum, Hein; Htet, Aung Soe & Bjertness, Espen [Vis alle 8 forfattere av denne artikkelen] (2019). Comparison of Cardiovascular Risk Factors among Somalis Living in Norway and Somaliland. International Journal of Environmental Research and Public Health (IJERPH). ISSN 1661-7827. 16(13), s. 1–12. doi: 10.3390/ijerph16132353. Fulltekst i vitenarkiv Vis sammendrag

  Objective: We aimed to assess and compare cardiovascular disease (CVD) risk factors and predict the future risk of CVD among Somalis living in Norway and Somaliland. Method: We included participants (20–69 years) from two cross-sectional studies among Somalis living in Oslo (n = 212) and Hargeisa (n = 1098). Demographic data, history of CVD, smoking, alcohol consumption, anthropometric measures, blood pressure, fasting serum glucose, and lipid profiles were collected. The predicted 10-year risk of CVD was calculated using Framingham risk score models. Results: In women, systolic and diastolic blood pressure were significantly higher in Hargeisa compared to Oslo (p < 0.001), whereas no significant differences were seen in men. The ratio of total cholesterol to high-density lipoprotein (HDL) cholesterol was significantly higher in Hargeisa compared to Oslo among both men (4.4 versus 3.9, p = 0.001) and women (4.1 versus 3.3, p < 0.001). Compared to women, men had higher Framingham risk scores, but there were no significant differences in Framingham risk scores between Somalis in Oslo and Hargeisa. Conclusion: In spite of the high body mass index (BMI) in Oslo, most CVD risk factors were higher among Somali women living in Hargeisa compared to those in Oslo, with similar patterns suggested in men. However, the predicted CVD risks based on Framingham models were not different between the locations.

• Ahmed, Soheir H.; Meyer, Haakon E; Kjøllesdal, Marte Karoline Råberg; Marjerrison, Niki; Mdala, Ibrahimu & Htet, Aung Soe [Vis alle 8 forfattere av denne artikkelen] (2019). The prevalence of selected risk factors for non-communicable diseases in Hargeisa, Somaliland: a cross-sectional study. BMC Public Health. 19(1). doi: 10.1186/s12889-019-7101-x. Fulltekst i vitenarkiv Vis sammendrag

  Background Non-communicable diseases (NCDs), particularly cardiovascular diseases, diabetes, respiratory conditions and cancers, are the most common causes of morbidity and mortality globally. Information on the prevalence estimates of NCD risk factors such as smoking, low fruit & vegetable intake, physical inactivity, raised blood pressure, overweight, obesity and abnormal blood lipid are scarce in Somaliland. The aim of this study was to determine the prevalence of these selected risk factors for NCDs among 20–69 year old women and men in Hargeisa, Somaliland. Methods A cross-sectional study was conducted in five districts of Hargeisa (Somaliland), using the STEPwise approach to noncommunicable disease risk factor surveillance (STEPS) to collect data on demographic and behavioral characteristics and physical measurements (n = 1100). The STEPS approach is a standardized method for collecting, analysing and disseminating data on NCD risk factor burden. Fasting blood sugar, serum lipids (total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides) were collected in half of the participants. Results The vast majority of participants had ≤1 serving of fruits daily (97.7%) and ≤ 1 serving of vegetables daily (98.2%). The proportion of participants with low physical activity levels was 78.4%. The overall prevalence of high salt intake was 18.5%. The prevalence of smoking and khat chewing among men was 27 and 37% respectively, and negligible among women. In women, the prevalence of hypertension increased from 15% in the age group 20–34 years to 67% in the age group 50–69 years, the prevalence of overweight and obesity (BMI ≥ 25 kg/m2) from 51 to 73%, and the prevalence of diabetes from 3 to 22%. Similar age-trends were seen in men. Conclusion Most of the selected risk factors for noncommunicable diseases were high and increased by age in both women and men. Overweight and obesity and low physical activity needs intervention in women, while hypertension and low fruit and vegetable consumption needs intervention in both men and women. Somaliland health authorities should develop and/or strengthen health services that can help in treating persons with hypertension and hyperlipidaemia, and prevent a future burden of NCDs resulting from a high prevalence of NCD risk factors.

Se alle arbeider i NVA

• Marjerrison, Niki; Grimsrud, Tom Kristian; Hansen, Johnni; Martinsen, Jan Ivar; Nordby, Karl-Christian & Olsen, Raymond [Vis alle 9 forfattere av denne artikkelen] (2025). Occupational exposures of firefighting and prostate cancer risk in the Norwegian fire departments cohort. Occupational and Environmental Medicine. ISSN 1351-0711. 82(Suppl. 1). doi: 10.1136/oemed-2024-epicohabstracts.3. Fulltekst i vitenarkiv Vis sammendrag

  Objectives: In their 2022 classification of firefighting as carcinogenic, the International Agency for Research on Cancer deemed the evidence of the association with prostate cancer (PC) ‘limited’, citing an inability to rule out that a medical surveillance bias fully explained firefighters’ excess PC incidence compared to the general population. Our aim was to compare PC risk within a firefighter cohort, applying indicators of exposures. Methods: We used employment duration and the indicators fire exposure score, inhalation score and diesel exhaust exposure score to examine PC risk among men in the Norwegian Fire Departments Cohort (n=4251). Incident PC cases, including clinical characteristics, were obtained from the Cancer Registry of Norway (1960–2021). Cox regression was used to estimate hazard ratios (HRs) by cumulative exposure in tertiles (reference: lowest) for all, aggressive, and indolent PCs, with adjustment for age and birth cohort. The cumulative incidence of PC across birth cohorts and diagnostic periods was examined. Results: During 123,835 person-years of follow-up, there were 268 PC cases (61 aggressive, 69 indolent, 138 unclassifiable). No clear associations emerged for any of the exposure indicators, although elevated HRs were observed for aggressive PCs in the highest tertile of fire exposure score compared to the lowest (1.51, 95% CI 0.63–2.72), and for indolent PCs in the highest tertile of inhalation score compared to the lowest (1.31, 95% CI 0.60–2.89). Assessment of cumulative incidence by stage demonstrated a greater number of diagnoses of indolent and unclassifiable PC at younger ages from 1990. Conclusions: We did not observe clear associations between our exposure indicators and PC risk. However, our study had few cases in analyses by clinical stage. Studies of PC risk among firefighters remain challenged by difficulties in exposure characterization and a limited understanding of PC etiology, as well as the unclear magnitude of a medical surveillance bias. Funding: This work was funded by the Foundation Dam (grant no: 2019/FO247424), Cancer Society of Norway, Norwegian Firefighters Fight Cancer, Norwegian Union of Municipal and General Employees, Norwegian Union of Marine Engineers, and the Fire Union in Delta. Acknowledgements: We wish to thank Jarle Jakobsen (Nordland Hospital, Bodø, Norway) for his work in the early stages of this study. We also wish to thank the fire departments that collected and shared their data that constitutes the Norwegian Fire Departments Cohort, as well as our project reference group (comprising representatives from firefighters’ unions, employers’ organisations, the volunteer organisation ‘Norwegian Firefighters Fighting Cancer’, the Norwegian Directorate for Civil Protection, the Norwegian Labour Inspection Authority, and the Norwegian Cancer Society) for their contributions to the project.

• Marjerrison, Niki & Wojewodzic, Marcin Wlodzimierz (2025). Using the population-based Janus Serum Bank as a ‘Time Machine’ to explore testicular cancer and its relationship with exposure to PFAS ‘Forever Chemicals’. Fulltekst i vitenarkiv
• Wojewodzic, Marcin Wlodzimierz & Marjerrison, Niki (2025). Gathering evidence of Per- and polyfluoroalkyl substances causing testicular cancer. Fulltekst i vitenarkiv
• Sandsund, Mariann; Kjærheim, Kristina; Li, Tian; Marjerrison, Niki; Olsen, Raymond & Renberg, Julie [Vis alle 9 forfattere av denne artikkelen] (2024). Health Risks and Health Effects of Firefighter Work: A Multidisciplinary Project using Register Data, Laboratory Studies and Real Fire Scenarios. Fulltekst i vitenarkiv Vis sammendrag

  Publisher: International Society for Environmental Ergonomics ISBN: 979-11-987858-0-0 (13590) 20th International Conference on Environmental Ergonomics, 3-7th June 2024, Jeju, Republic of Korea

• Færevik, Hilde; Sandsund, Mariann; Marjerrison, Niki; Li, Tian & Olsen, Raymond (2023). Webinar: The HERO project - Health risks and health effects of firefighter work. Fulltekst i vitenarkiv Vis sammendrag

  The project will study cancer incidence using register data and exposure estimates, and describe penetration of toxic smoke particles, gases and vapours in small-scale scenarios and in real fire scenarios. In addition, thermoregulatory responses in male and female firefighters will be studied. This will form the basis for development of measures to be used by manufacturers to improve their products related to protection of firefighters, changes in practice and supplementary knowledge that can lead to a reduction in the incidence of cancer among firefighters and more effective coordination between public agencies and fire safety actors. Health and occupational research groups at SINTEF, National Institute of Occupational Health (STAMI), the Cancer Registry of Norway (CRN) and RISE Fire Research will collaborate to generate knowledge about these topics. The project also collaborates with the Fire Research and Innovation Centre – FRIC, as well as an international advisory expert group and a reference group of representatives from firefighter departments, authorities, scientists and producers of firefighter clothing. Hot environmental conditions and high work intensity expose firefighters to significant levels of thermoregulatory stress. Also, many known and suspected carcinogenic substances have been demonstrated during knock down and overhaul of fires. In addition to direct exposure during firefighting, the personal protective equipment and gears may be an important source of hazardous exposures. An increased demand for new knowledge and a better understanding of factors leading to health problems/illnesses among firefighters is needed.

• Færevik, Hilde; Olsen, Raymond & Marjerrison, Niki (2023). Brannkonstablers helse - en stor samfunnsutfordring? Paneldebatt. Fulltekst i vitenarkiv Vis sammendrag

  «Det store brannløftet» var en gave fra Gjensidigestiftelsen til det norske samfunn på 350 millioner kroner. Prosjektet omfatter ulike tiltak som på kort og lang sikt vil trygge hverdagen til befolkningen ytterligere. En del av gaven anvendes på forskning. Konferansen formidlet viktig kunnskap fra denne forskningen, og ønsker å skape debatt og dialog om hva som er viktig å fokusere på innen brannforskning fremover. VI presenterte prosjektet HERO - helserisiko og helseforebygging hos brannkonstabler

• Færevik, Hilde; Sandsund, Mariann; Renberg, Julie; Li, Tian; Marjerrison, Niki & Kjærheim, Kristina [Vis alle 7 forfattere av denne artikkelen] (2022). HERO - Helserisiko og helseeffekter av brannslukking - resultater fra arbeidspakkene. Fulltekst i vitenarkiv
• Marjerrison, Niki; Grimsrud, Tom Kristian; Hansen, Johnnie; Martinsen, Jan Ivar; Nordby, Karl-Christian & Veierød, Marit Bragelien [Vis alle 7 forfattere av denne artikkelen] (2022). Cancer incidence and mortality in the Norwegian Fire Departments cohort: Are incidence versus mortality outcome measures contributing to variability in risk estimates? Fulltekst i vitenarkiv
• Marjerrison, Niki; Jakobsen, Jarle; Grimsrud, Tom Kristian; Hansen, Johnnie; Martinsen, Jan Ivar & Nordby, Karl-Christian [Vis alle 8 forfattere av denne artikkelen] (2022). Cancer incidence and mortality in the Norwegian Fire Departments Cohort, 1960-2018. Fulltekst i vitenarkiv
• Færevik, Hilde; Renberg, Julie; Sandsund, Mariann; Marjerrison, Niki & Kjærheim, Kristina (2022). Health effects and health risk of firefighting. Fulltekst i vitenarkiv
• Marjerrison, Niki (2022). WP1: Exposure-related cancer risk among Norwegian firefighters. Fulltekst i vitenarkiv
• Marjerrison, Niki (2022). Eksponeringsrelatert kreftrisiko blant brannmenn. Fulltekst i vitenarkiv
• Marjerrison, Niki (2022). Cancer incidence in sites potentially related to occupational exposures: 58 years of follow-up of firefighters in the Norwegian Fire Departments Cohort. Fulltekst i vitenarkiv
• Marjerrison, Niki (2022). AP1: Kreftrisiko blant brannmenn. Fulltekst i vitenarkiv
• Marjerrison, Niki (2022). Cancer risk among firefighters. Fulltekst i vitenarkiv
• Marjerrison, Niki (2022). Cancer risk among Norwegian firefighters. Fulltekst i vitenarkiv
• Marjerrison, Niki; Kjærheim, Jenny Kristina; Stenehjem, Jo; Grimsrud, Tom Kristian; Veierød, Marit Bragelien & Martinsen, Jan Ivar [Vis alle 9 forfattere av denne artikkelen] (2025). Kreftrisiko blant brannkonstabler 2015–2024. Folkehelseinstituttet. Fulltekst i vitenarkiv Vis sammendrag

  Rapporten undersøker kreftrisiko blant norske brannkonstabler basert på en stor kohortstudie med nær 4700 ansatte fra 15 brannvesen. Studien viser at brannkonstabler har høyere forekomst av enkelte kreftformer enn den generelle befolkningen, særlig urinveiskreft, mesoteliom (brysthinnekreft), strupekreft, prostatakreft og tarmkreft. Risikoen var størst blant personer med lang ansettelsestid og blant dem som arbeidet i de tidligste periodene. Funnene gir særlig støtte til en sammenheng mellom yrkeseksponering ved brannslokking og risiko for urinveiskreft og mesoteliom. For prostatakreft kan den økte forekomsten delvis forklares av tidligere og hyppigere diagnostisering. Rapporten konkluderer med at resultatene støtter IARCs vurdering av brannyrket som kreftfremkallende, og understreker behovet for fortsatt forebygging og videre forskning på helsekonsekvenser av brannyrket

Se alle arbeider i NVA