ID Number		2576
Study Type		Epidemiology
Model		This study examines the association between RF and ELF exposure and brain tumors in the large-scale INTEROCC study.
Details		AUTHORS' ABSTRACT: Turner, Bowman, Cardis et al. 2014 (IEEE #6338): BACKGROUND: Occupational exposure to extremely low-frequency magnetic fields (ELF) is a suspected risk factor for brain tumors, however the literature is inconsistent. Few studies have assessed whether ELF in different time windows of exposure may be associated with specific histologic types of brain tumors. This study examines the association between ELF and brain tumors in the large-scale INTEROCC study. METHODS: Cases of adult primary glioma and meningioma were recruited in seven countries (Australia, Canada, France, Germany, Israel, New Zealand, and the United Kingdom) between 2000 and 2004. Estimates of mean workday ELF exposure based on a job exposure matrix were assigned. Estimates of cumulative exposure, average exposure, maximum exposure, and exposure duration were calculated for the lifetime, and 1 to 4, 5 to 9, and 10+ years before the diagnosis/reference date. RESULTS: There were 3,761 included brain tumor cases (1,939 glioma and 1,822 meningioma) and 5,404 population controls. There was no association between lifetime cumulative ELF exposure and glioma or meningioma risk. However, there were positive associations between cumulative ELF 1 to 4 years before the diagnosis/reference date and glioma [odds ratio (OR) e 90th percentile vs. < 25th percentile, 1.67; 95% confidence interval (CI), 1.36-2.07; PLinear trend < 0.0001], and, somewhat weaker associations with meningioma (OR e 90th percentile vs. < 25th percentile, 1.23; 95% CI, 0.97-1.57; PLinear trend = 0.02). CONCLUSIONS: Results showed positive associations between ELF in the recent past and glioma. IMPACT: Occupational ELF exposure may play a role in the later stages (promotion and progression) of brain tumorigenesis. AUTHORS' ABSTRACT: Vila, Cardis et al. 2018 (IEEE #7053): INTRODUCTION: In 2011, the International Agency for Research on Cancer classified radiofrequency (RF) electromagnetic fields (EMF) as possibly carcinogenic to humans (group 2B), although the epidemiological evidence for the association between occupational exposure to RF-EMF and cancer was judged to be inadequate, due in part to limitations in exposure assessment. This study examines the relation between occupational RF and intermediate frequency (IF) EMF exposure and brain tumor (glioma and meningioma) risk in the INTEROCC multinational population-based case-control study (with nearly 4000 cases and over 5000 controls), using a novel exposure assessment approach. METHODS: Individual indices of cumulative exposure to RF and IF-EMF (overall and in specific exposure time windows) were assigned to study participants using a source-exposure matrix and detailed interview data on work with or nearby EMF sources. Conditional logistic regression was used to investigate associations with glioma and meningioma risk. RESULTS: Overall, around 10% of study participants were exposed to RF while only 1% were exposed to IF-EMF. There was no clear evidence for a positive association between RF or IF-EMF and the brain tumors studied, with most results showing either no association or odds ratios (ORs) below 1.0. The largest adjusted ORs were obtained for cumulative exposure to RF magnetic fields (as A/m-years) in the highest exposed category (e90th percentile) for the most recent exposure time window (1-4/years before the diagnosis or reference date) for both glioma, OR/=/1.62 (95% confidence interval (CI): 0.86, 3.01) and meningioma (OR/=/1.52, 95% CI: 0.65, 3.55). CONCLUSION: Despite the improved exposure assessment approach used in this study, no clear associations were identified. However, the results obtained for recent exposure to RF electric and magnetic fields are suggestive of a potential role in brain tumor promotion/progression and should be further investigated. AUTHOR'S ABSTRACT: Mortazavi 2018 (IEEE #7054): This commentary addresses the paper by Vila et al. entitled "Occupational exposure to high-frequency electromagnetic fields and brain tumor risk in the INTEROCC study: An individualized assessment approach" that is published in Environment International. The authors have examined the link between occupational exposures to radiofrequency (RF) and intermediate frequency (IF) electromagnetic fields (EMF) and glioma and meningioma brain tumor risk in the INTEROCC multinational population-based case-control study. This study showed no clear association with exposure to RF or IF EMFs and the risk of glioma or meningioma brain tumors. Recent studies show that in many cases there are large errors and/or major shortcomings in the studies claiming no link between mobile phone and brain cancer. Although the paper by Vila et al. is well-structured and can be considered as a significant contribution to this field, there are several items that merit further attention and are not fully addressed. These include the selection bias, confounding factors other than age, sex, region and country, and criteria used in this study for considering exposures as occupational.
Findings		Effects
Status		Completed With Publication
Principal Investigator		CREAL (Centre for Res in Env Epidemiology, Barcelo
Funding Agency		NIH, USA
Country		SPAIN
References		Turner, MC et al. Cancer Epidemiol Biomarkers Prev., (2014) 23:1863-1872 Vila, J et al. Journal of Exposure Science and Environmental Epidemiology., (2016) :doi: 10.1038/jes.2016.60- Vila, J et al. Environ Int., (2018) 119:353-365 Mortazavi, SM Environ Int. , (2018) 121:1024- Vila, J et al. Environment International., (2018) 121:1025-1026
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