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Brabant C, Geerinck A, Beaudart C, Tirelli E, Geuzaine C, Bruyère O. Exposure to magnetic fields and childhood leukemia: a systematic review and meta-analysis of case-control and cohort studies. REVIEWS ON ENVIRONMENTAL HEALTH 2023; 38:229-253. [PMID: 35302721 DOI: 10.1515/reveh-2021-0112] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 02/13/2022] [Indexed: 06/02/2023]
Abstract
The association between childhood leukemia and extremely low frequency magnetic fields (ELF-MF) generated by power lines and various electric appliances has been studied extensively during the past 40 years. However, the conditions under which ELF-MF represent a risk factor for leukemia are still unclear. Therefore, we have performed a systematic review and meta-analysis to clarify the relation between ELF-MF from several sources and childhood leukemia. We have systematically searched Medline, Scopus, Cochrane Database of Systematic Review and DARE to identify each article that has examined the relationship between ELF-MF and childhood leukemia. We have performed a global meta-analysis that takes into account the different measures used to assess magnetic field exposure: magnetic flux density measurements (<0.2 µT vs. >0.2 µT), distances between the child's home and power lines (>200 m vs. <200 m) and wire codings (low current configuration vs. high current configuration). Moreover, meta-analyses either based on magnetic flux densities, on proximity to power lines or on wire codings have been performed. The association between electric appliances and childhood leukemia has also been examined. Of the 863 references identified, 38 studies have been included in our systematic review. Our global meta-analysis indicated an association between childhood leukemia and ELF-MF (21 studies, pooled OR=1.26; 95% CI 1.06-1.49), an association mainly explained by the studies conducted before 2000 (earlier studies: pooled OR=1.51; 95% CI 1.26-1.80 vs. later studies: pooled OR=1.04; 95% CI 0.84-1.29). Our meta-analyses based only on magnetic field measurements indicated that the magnetic flux density threshold associated with childhood leukemia is higher than 0.4 µT (12 studies, >0.4 µT: pooled OR=1.37; 95% CI 1.05-1.80; acute lymphoblastic leukemia alone: seven studies, >0.4 µT: pooled OR=1.88; 95% CI 1.31-2.70). Lower magnetic fields were not associated with leukemia (12 studies, 0.1-0.2 µT: pooled OR=1.04; 95% CI 0.88-1.24; 0.2-0.4 µT: pooled OR=1.07; 95% CI 0.87-1.30). Our meta-analyses based only on distances (five studies) showed that the pooled ORs for living within 50 m and 200 m of power lines were 1.11 (95% CI 0.81-1.52) and 0.98 (95% CI 0.85-1.12), respectively. The pooled OR for living within 50 m of power lines and acute lymphoblastic leukemia analyzed separately was 1.44 (95% CI 0.72-2.88). Our meta-analyses based only on wire codings (five studies) indicated that the pooled OR for the very high current configuration (VHCC) was 1.23 (95% CI 0.72-2.10). Finally, the risk of childhood leukemia was increased after exposure to electric blankets (four studies, pooled OR=2.75; 95% CI 1.71-4.42) and, to a lesser extent, electric clocks (four studies, pooled OR=1.27; 95% CI 1.01-1.60). Our results suggest that ELF-MF higher than 0.4 µT can increase the risk of developing leukemia in children, probably acute lymphoblastic leukemia. Prolonged exposure to electric appliances that generate magnetic fields higher than 0.4 µT like electric blankets is associated with a greater risk of childhood leukemia.
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Affiliation(s)
- Christian Brabant
- WHO Collaborating Centre for Public Health Aspects of Musculo-Skeletal Health and Ageing, Division of Public Health, Epidemiology and Health Economics, University of Liège, Liège, Belgium
- Department of Psychology, Cognition and Behavior, University of Liège, Liège, Belgium
| | - Anton Geerinck
- WHO Collaborating Centre for Public Health Aspects of Musculo-Skeletal Health and Ageing, Division of Public Health, Epidemiology and Health Economics, University of Liège, Liège, Belgium
| | - Charlotte Beaudart
- WHO Collaborating Centre for Public Health Aspects of Musculo-Skeletal Health and Ageing, Division of Public Health, Epidemiology and Health Economics, University of Liège, Liège, Belgium
| | - Ezio Tirelli
- Department of Psychology, Cognition and Behavior, University of Liège, Liège, Belgium
| | - Christophe Geuzaine
- Department of Electricity, Electronics and Computer Sciences (Montefiore Institute), University of Liège, Liège, Belgium
| | - Olivier Bruyère
- WHO Collaborating Centre for Public Health Aspects of Musculo-Skeletal Health and Ageing, Division of Public Health, Epidemiology and Health Economics, University of Liège, Liège, Belgium
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Amoon AT, Swanson J, Magnani C, Johansen C, Kheifets L. Pooled analysis of recent studies of magnetic fields and childhood leukemia. ENVIRONMENTAL RESEARCH 2022; 204:111993. [PMID: 34481821 DOI: 10.1016/j.envres.2021.111993] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 08/23/2021] [Accepted: 08/30/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Over forty epidemiologic studies have addressed an association between measured or calculated extremely-low-frequency magnetic fields (MF) and childhood leukemia. These studies have been aggregated in a series of pooled analyses, but it has been 10 years since the last such. METHODS We present a pooled analysis combining individual-level data (24,994 cases, 30,769 controls) from four recent studies on MF and childhood leukemia. RESULTS Unlike previous pooled analyses, we found no increased risk of leukemia among children exposed to greater MF: odds ratio (OR) = 1.01, for exposure ≥0.4 μT (μT) compared with exposures <0.1 μT. Similarly, no association was observed in the subset of acute lymphoblastic leukemia, birth homes, studies using calculated fields, or when geocoding accuracy was ignored. In these studies, there is a decline in risk over time, also evident when we compare three pooled analyses. A meta-analysis of the three pooled analyses overall presents an OR of 1.45 (95% CI: 0.95-2.20) for exposures ≥0.4 μT. CONCLUSIONS Our results are not in line with previous pooled analysis and show a decrease in effect to no association between MF and childhood leukemia. This could be due to methodological issues, random chance, or a true finding of disappearing effect.
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Affiliation(s)
- Aryana T Amoon
- University of California, Department of Epidemiology, Los Angeles, CA, USA; County of Los Angeles, Department of Public Health, Office of Health Assessment and Epidemiology. Los Angeles, CA, USA.
| | | | - Corrado Magnani
- University of Eastern Piedmont and CPO Piemonte, Medical Statistics & Cancer Epidemiology Unit-Department of Translational Medicine, Novara, Italy
| | - Christoffer Johansen
- Rigshospitalet, Department of Oncology-Cancer Survivorship and Late Treatment Late Effects (CASTLE) Unit, Copenhagen, Denmark
| | - Leeka Kheifets
- University of California, Department of Epidemiology, Los Angeles, CA, USA
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Onyije FM, Olsson A, Baaken D, Erdmann F, Stanulla M, Wollschläger D, Schüz J. Environmental Risk Factors for Childhood Acute Lymphoblastic Leukemia: An Umbrella Review. Cancers (Basel) 2022; 14:382. [PMID: 35053543 PMCID: PMC8773598 DOI: 10.3390/cancers14020382] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 01/05/2022] [Accepted: 01/11/2022] [Indexed: 02/05/2023] Open
Abstract
Leukemia is the most common type of cancer among children and adolescents worldwide. The aim of this umbrella review was (1) to provide a synthesis of the environmental risk factors for the onset of childhood acute lymphoblastic leukemia (ALL) by exposure window, (2) evaluate their strength of evidence and magnitude of risk, and as an example (3) estimate the prevalence in the German population, which determines the relevance at the population level. Relevant systematic reviews and pooled analyses were identified and retrieved through PubMed, Web of Science databases and lists of references. Only two risk factors (low doses of ionizing radiation in early childhood and general pesticide exposure during maternal preconception/pregnancy) were convincingly associated with childhood ALL. Other risk factors including extremely low frequency electromagnetic field (ELF-MF), living in proximity to nuclear facilities, petroleum, benzene, solvent, and domestic paint exposure during early childhood, all showed some level of evidence of association. Maternal consumption of coffee (high consumption/>2 cups/day) and cola (high consumption) during pregnancy, paternal smoking during the pregnancy of the index child, maternal intake of fertility treatment, high birth weight (≥4000 g) and caesarean delivery were also found to have some level of evidence of association. Maternal folic acid and vitamins intake, breastfeeding (≥6 months) and day-care attendance, were inversely associated with childhood ALL with some evidence. The results of this umbrella review should be interpreted with caution; as the evidence stems almost exclusively from case-control studies, where selection and recall bias are potential concerns, and whether the empirically observed association reflect causal relationships remains an open question. Hence, improved exposure assessment methods including accurate and reliable measurement, probing questions and better interview techniques are required to establish causative risk factors of childhood leukemia, which is needed for the ultimate goal of primary prevention.
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Affiliation(s)
- Felix M. Onyije
- Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer (IARC/WHO), 150 Cours Albert Thomas, CEDEX 08, 69372 Lyon, France; (A.O.); (F.E.); (J.S.)
| | - Ann Olsson
- Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer (IARC/WHO), 150 Cours Albert Thomas, CEDEX 08, 69372 Lyon, France; (A.O.); (F.E.); (J.S.)
| | - Dan Baaken
- Division of Childhood Cancer Epidemiology, Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany; (D.B.); (D.W.)
| | - Friederike Erdmann
- Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer (IARC/WHO), 150 Cours Albert Thomas, CEDEX 08, 69372 Lyon, France; (A.O.); (F.E.); (J.S.)
- Division of Childhood Cancer Epidemiology, Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany; (D.B.); (D.W.)
| | - Martin Stanulla
- Pediatric Hematology and Oncology, Hannover Medical School, Carl-Neuberg-Str 1, 30625 Hannover, Germany;
| | - Daniel Wollschläger
- Division of Childhood Cancer Epidemiology, Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany; (D.B.); (D.W.)
| | - Joachim Schüz
- Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer (IARC/WHO), 150 Cours Albert Thomas, CEDEX 08, 69372 Lyon, France; (A.O.); (F.E.); (J.S.)
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Amoon AT, Swanson J, Vergara X, Kheifets L. Relationship between distance to overhead power lines and calculated fields in two studies. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2020; 40:431-443. [PMID: 32066122 DOI: 10.1088/1361-6498/ab7730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
There is some evidence that both distance from transmission lines and measured or calculated magnetic fields are associated with childhood leukemia. Because distance is a key component when calculating the magnetic field generated by power lines, distance from lines and calculated fields based on lines tend to be highly correlated. Socioeconomic status (SES) and dwelling type are also associated with magnetic field exposure. We used exposure data from two large studies of childhood leukemia and other cancers, in the US and the UK, to describe a relationship between distance and magnetic fields across the population within 100 meters (m) of power lines as a whole and evaluate potential modifiers such as SES and type of dwelling. There were 387 subjects living within 100 m of an overhead power line. There was no significant difference in mean calculated fields or distance to 200+ kV lines within 100 m by study. Within the range where the power-line field is expected to be significant compared to other sources, which we take as 100 m, distance to high-voltage lines predicted magnetic field (MF) variation in both studies better than other functions of distance tested in both linear and logistic regression. There were no differences between high and low SES or dwelling types (single-family home versus other). In conclusion, we found that calculated fields do appear to diminish linearly with increasing distance from overhead power lines, up to 100 m, particularly those 200+ kV and above. These results are stronger in the UK study. Within 100 m, distance to high-voltage lines continues to be highly correlated with calculated MFs and each can be a proxy for the other.
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Affiliation(s)
- A T Amoon
- UCLA Fielding School of Public Health, Los Angeles, CA 90024, United States of America
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Gaps in Knowledge Relevant to the "Guidelines for Limiting Exposure to Time-Varying Electric and Magnetic Fields (1 Hz-100 kHz)". HEALTH PHYSICS 2020; 118:533-542. [PMID: 32251081 DOI: 10.1097/hp.0000000000001261] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Sources of low-frequency fields are widely found in modern society. All wires or devices carrying or using electricity generate extremely low frequency (ELF) electric fields (EFs) and magnetic fields (MFs), but they decline rapidly with distance to the source. High magnetic flux densities are usually found in the vicinity of power lines and close to equipment using strong electrical currents, but can also be found in buildings with unbalanced return currents, or indoor transformer stations. For decades, epidemiological as well as experimental studies have addressed possible health effects of exposure to ELF-MFs. The main goal of ICNIRP is to protect people and the environment from detrimental exposure to all forms of non-ionizing radiation (NIR). To this end, ICNIRP provides advice and guidance by developing and disseminating exposure guidelines based on the available scientific research. Research in the low-frequency range began more than 40 years ago, and there is now a large body of literature available on which ICNIRP set its protection guidelines. A review of the literature has been carried out to identify possible relevant knowledge gaps, and the aim of this statement is to describe data gaps in research that would, if addressed, assist ICNIRP in further developing guidelines and setting revised recommendations on limiting exposure to electric and magnetic fields. It is articulated in two parts: the main document, which reviews the science related to LF data gaps, and the annex, which explains the methodology used to identify the data gaps.
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Fei Y, Su L, Lou H, Zhao C, Wang Y, Chen G. The effects of 50 Hz magnetic field-exposed cell culture medium on cellular functions in FL cells. JOURNAL OF RADIATION RESEARCH 2019; 60:424-431. [PMID: 31111909 PMCID: PMC6640911 DOI: 10.1093/jrr/rrz020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/22/2019] [Indexed: 05/19/2023]
Abstract
Although extremely low frequency magnetic fields (ELF-MFs) have been classified as a possible carcinogen for humans by the International Agency for Research on Cancer (IARC), their biological effects and underlying mechanisms are still unclear. Our previous study indicated that ELF-MF exposure influenced the relative permittivity of the saline solution, suggesting that the MF exposure altered physical properties of the solution. To explore the biophysical mechanism of ELF-MF-induced biological effects, this study examined the effects of 50 Hz sinusoidal MF at 0-4.0 mT on the permittivity of culture medium with phase-interrogation surface plasmon resonance (SPR) sensing. Then, the biological effects of MF pre-exposed culture medium on cell viability, the mitogen-activated protein kinase (MAPK) signaling pathways, oxidative stress, and genetic stabilities were analyzed using Cell Counting Kit-8, western blot, flow cytometry, γH2AX foci formation, and comet assay. The results showed that SPR signals were decreased under MF exposure in a time- and dose-dependent manner, and the decreased SPR signals were reversible when the exposure was drawn off. However, MF pre-exposed culture medium did not significantly change cell viability, intracellular reactive oxygen species level, activation of the MARK signaling pathways, or genetic stabilities in human amniotic epithelial cells (FL cells). In conclusion, our data suggest that the relative permittivity of culture medium was influenced by 50 Hz MF exposure, but this change did not affect the biological processes in FL cells.
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Affiliation(s)
- Yue Fei
- Bioelectromagnetics Laboratory, and Department of Reproductive Endocrinology of Women’s Hospital, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, China
| | - Liling Su
- Bioelectromagnetics Laboratory, and Department of Reproductive Endocrinology of Women’s Hospital, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, China
- Department of Clinical Medicine, Jiangxi Medical College, Zhimin Road, Shangrao, China
| | - Haifeng Lou
- Bioelectromagnetics Laboratory, and Department of Reproductive Endocrinology of Women’s Hospital, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, China
| | - Chuning Zhao
- Bioelectromagnetics Laboratory, and Department of Reproductive Endocrinology of Women’s Hospital, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, China
| | - Yiqin Wang
- State Key Laboratory of Modern Optical Instrumentation (Zhejiang University), Centre for Optical and Electromagnetics Research, Zhejiang Provincial Key Laboratory for Sensing Technologies, JORCEP (Sino-Swedish Joint Research Center of Photonics), Zhejiang University, 866 Yuhangtang Road, Hangzhou, China
| | - Guangdi Chen
- Bioelectromagnetics Laboratory, and Department of Reproductive Endocrinology of Women’s Hospital, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, China
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7
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Swanson J, Kheifets L, Vergara X. Changes over time in the reported risk for childhood leukaemia and magnetic fields. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2019; 39:470-488. [PMID: 30736028 DOI: 10.1088/1361-6498/ab0586] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
There have been many studies from 1979 to the present reporting raised risks for childhood leukaemia with exposure to power-frequency magnetic fields. There are also suggestions that the reported risk has been decreasing. We examine trends in the risk over time from all available studies. For 41 studies, we combine reported risks using inverse-variance weighting, drawing risk estimates from previous pooled analyses where possible for greater consistency. We examine the cumulative risk for studies published up to each successive calendar year for all studies and for various subsets, and test for a trend over the period. The cumulative relative risk has indeed declined, for our most rigorous analysis from a maximum 2.44 in 1997 to 1.58 in 2017, but not statistically significantly when tested as a linear trend. We find suggestions of higher risks in studies looking at higher exposures and in studies with better quality exposure assessment. We conclude that there is a decline in reported risk from the mid 1990s to now, which is unlikely to be solely explained by improving study quality but may be due to chance, and an elevated risk remains.
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Affiliation(s)
- J Swanson
- National Grid, London, United Kingdom
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Draper GJ, Bithell JF, Bunch KJ, Kendall GM, Murphy MFG, Stiller CA. Childhood cancer research in Oxford II: The Childhood Cancer Research Group. Br J Cancer 2018; 119:763-770. [PMID: 30131553 PMCID: PMC6173767 DOI: 10.1038/s41416-018-0181-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 05/26/2018] [Accepted: 06/20/2018] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND We summarise the work of the Childhood Cancer Research Group, particularly in relation to the UK National Registry of Childhood Tumours (NRCT). METHODS The Group was responsible for setting up and maintaining the NRCT. This registry was based on notifications from regional cancer registries, specialist children's tumour registries, paediatric oncologists and clinical trials organisers. For a large sample of cases, data on controls matched by date and place of birth were also collected. RESULTS Significant achievements of the Group include: studies of aetiology and of genetic epidemiology; proposals for, and participation in, international comparative studies of these diseases and on a classification system specifically for childhood cancer; the initial development of, and major contributions to, follow-up studies of the health of long-term survivors; the enhancement of cancer registration records by the addition of clinical data and of birth records. The Group made substantial contributions to the UK government's Committee on Medical Aspects of Radiation in the Environment. CONCLUSION An important part of the ethos of the Group was to work in collaboration with many other organisations and individuals, both nationally and internationally: many of the Group's achievements described here were the result of such collaborations.
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Affiliation(s)
- Gerald J Draper
- Department of Statistics, University of Oxford, 24-29 St Giles, Oxford, OX1 3LB, UK.
| | - John F Bithell
- Department of Statistics, University of Oxford, 24-29 St Giles, Oxford, OX1 3LB, UK
| | - Kathryn J Bunch
- National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Richard Doll Building, Old Road Campus, Oxford, OX3 7LF, UK
| | - Gerald M Kendall
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Richard Doll Building, Old Road Campus, Oxford, OX3 7LF, UK
| | - Michael F G Murphy
- Nuffield Department of Women's and Reproductive Health, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Charles A Stiller
- National Cancer Registration and Analysis Service, Public Health England, Chancellor Court, Oxford Business Park South, Oxford, OX4 2GX, UK
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Amoon AT, Crespi CM, Ahlbom A, Bhatnagar M, Bray I, Bunch KJ, Clavel J, Feychting M, Hémon D, Johansen C, Kreis C, Malagoli C, Marquant F, Pedersen C, Raaschou-Nielsen O, Röösli M, Spycher BD, Sudan M, Swanson J, Tittarelli A, Tuck DM, Tynes T, Vergara X, Vinceti M, Wünsch-Filho V, Kheifets L. Proximity to overhead power lines and childhood leukaemia: an international pooled analysis. Br J Cancer 2018; 119:364-373. [PMID: 29808013 PMCID: PMC6068168 DOI: 10.1038/s41416-018-0097-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 03/14/2018] [Accepted: 04/06/2018] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Although studies have consistently found an association between childhood leukaemia risk and magnetic fields, the associations between childhood leukaemia and distance to overhead power lines have been inconsistent. We pooled data from multiple studies to assess the association with distance and evaluate whether it is due to magnetic fields or other factors associated with distance from lines. METHODS We present a pooled analysis combining individual-level data (29,049 cases and 68,231 controls) from 11 record-based studies. RESULTS There was no material association between childhood leukaemia and distance to nearest overhead power line of any voltage. Among children living < 50 m from 200 + kV power lines, the adjusted odds ratio for childhood leukaemia was 1.33 (95% CI: 0.92-1.93). The odds ratio was higher among children diagnosed before age 5 years. There was no association with calculated magnetic fields. Odds ratios remained unchanged with adjustment for potential confounders. CONCLUSIONS In this first comprehensive pooled analysis of childhood leukaemia and distance to power lines, we found a small and imprecise risk for residences < 50 m of 200 + kV lines that was not explained by high magnetic fields. Reasons for the increased risk, found in this and many other studies, remains to be elucidated.
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Affiliation(s)
- Aryana T Amoon
- Department of Epidemiology, University of California Los Angeles Fielding School of Public Health, Los Angeles, CA, 90095-1772, USA
| | - Catherine M Crespi
- Department of Biostatistics, University of California Los Angeles Fielding School of Public Health, Los Angeles, CA, 90095-1772, USA
| | - Anders Ahlbom
- Unit of Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Megha Bhatnagar
- Department of Epidemiology, University of California Los Angeles Fielding School of Public Health, Los Angeles, CA, 90095-1772, USA
| | - Isabelle Bray
- Department of Health and Social Sciences, University of the West of England, Bristol, BS16 1QY, UK
| | - Kathryn J Bunch
- National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Headington, Oxford, OX3 7LF, UK
| | - Jacqueline Clavel
- Epidemiology of Childhood and Adolescent Cancers, CRESS, INSERM, UMR 1153, Paris Descartes University, Villejuif, France.,National Registry of Childhood Cancers - Hematological Malignancies, Villejuif, France
| | - Maria Feychting
- Unit of Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Denis Hémon
- Epidemiology of Childhood and Adolescent Cancers, CRESS, INSERM, UMR 1153, Paris Descartes University, Villejuif, France
| | - Christoffer Johansen
- The Danish Cancer Society Research Center, Strandboulevarden 49, 2100, Copenhagen, Denmark.,Oncology Clinic, Finsen Center, Rigshospitalet 5073, 2100, Copenhagen, Denmark
| | - Christian Kreis
- Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland
| | - Carlotta Malagoli
- Research Center of Environmental (CREAGEN), Genetic and Nutritional Epidemiology University of Modena and Reggio Emilia, Modena, Italy
| | - Fabienne Marquant
- Epidemiology of Childhood and Adolescent Cancers, CRESS, INSERM, UMR 1153, Paris Descartes University, Villejuif, France
| | - Camilla Pedersen
- The Danish Cancer Society Research Center, Strandboulevarden 49, 2100, Copenhagen, Denmark
| | - Ole Raaschou-Nielsen
- The Danish Cancer Society Research Center, Strandboulevarden 49, 2100, Copenhagen, Denmark.,Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000, Roskilde, Denmark
| | - Martin Röösli
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Petersgraben 1, Basel, Switzerland
| | - Ben D Spycher
- Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland
| | - Madhuri Sudan
- Department of Epidemiology, University of California Los Angeles Fielding School of Public Health, Los Angeles, CA, 90095-1772, USA.,Department of Public Health, Aarhus University, Aarhus, Denmark.,College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA, 91766-1854, USA
| | | | - Andrea Tittarelli
- Cancer Registry Unit, National Cancer Institute, Milan, 20133, Italy
| | - Deirdre M Tuck
- School of Medicine, University of Tasmania, Hobart, TAS, Australia.,Royal Hobart Hospital, Hobart, TAS, Australia
| | - Tore Tynes
- Department of Occupational Health Surveillance, National Institute of Occupational Health, Oslo, Norway
| | - Ximena Vergara
- Department of Epidemiology, University of California Los Angeles Fielding School of Public Health, Los Angeles, CA, 90095-1772, USA.,Energy and Environment Sector, Electric Power Research Institute, Palo Alto, CA, 94304, USA
| | - Marco Vinceti
- Research Center of Environmental (CREAGEN), Genetic and Nutritional Epidemiology University of Modena and Reggio Emilia, Modena, Italy.,Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA
| | - Victor Wünsch-Filho
- Department of Epidemiology, School of Public Health, University of São Paulo, São Paulo, 01246-904, Brazil
| | - Leeka Kheifets
- Department of Epidemiology, University of California Los Angeles Fielding School of Public Health, Los Angeles, CA, 90095-1772, USA.
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Kheifets L, Crespi CM, Hooper C, Cockburn M, Amoon AT, Vergara XP. Residential magnetic fields exposure and childhood leukemia: a population-based case-control study in California. Cancer Causes Control 2017; 28:1117-1123. [PMID: 28900736 DOI: 10.1007/s10552-017-0951-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 08/28/2017] [Indexed: 12/17/2022]
Abstract
PURPOSE Studies have reported an increased risk of childhood leukemia associated with exposure to magnetic fields. We conducted a large records-based case-control study of childhood leukemia risk and exposure to magnetic fields from power lines in California. METHODS The study included 5,788 childhood leukemia cases (born in and diagnosed in California 1986-2008) matched to population-based controls on age and sex. We calculated magnetic fields at birth addresses using geographic information systems, aerial imagery, historical information on load and phasing, and site visits. RESULTS Based on unconditional logistic regression controlling for age, sex, race/ethnicity, and socioeconomic status using subjects geocoded to a basic standard of accuracy, we report a slight risk deficit in two intermediate exposure groups and a small excess risk in the highest exposure group (odds ratio of 1.50 (95% confidence interval [0.70, 3.23])). Subgroup and sensitivity analyses as well as matched analyses gave similar results. All estimates had wide confidence intervals. CONCLUSION Our large, statewide, record-based case-control study of childhood leukemia in California does not in itself provide clear evidence of risk associated with greater exposure to magnetic fields from power lines, but could be viewed as consistent with previous findings of increased risk.
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Affiliation(s)
- Leeka Kheifets
- Department of Epidemiology, UCLA Fielding School of Public Health, 650 Charles E Young Drive South, Los Angeles, CA, 90024, USA.
| | - Catherine M Crespi
- Department of Biostatistics, UCLA Fielding School of Public Health, Los Angeles, CA, 90024, USA
| | | | - Myles Cockburn
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Aryana T Amoon
- Department of Epidemiology, UCLA Fielding School of Public Health, 650 Charles E Young Drive South, Los Angeles, CA, 90024, USA
| | - Ximena P Vergara
- Department of Epidemiology, UCLA Fielding School of Public Health, 650 Charles E Young Drive South, Los Angeles, CA, 90024, USA.,Energy and Environment, Electric Power Research Institute, Palo Alto, CA, 94304, USA
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Kheifets L, Swanson J, Yuan Y, Kusters C, Vergara X. Comparative analyses of studies of childhood leukemia and magnetic fields, radon and gamma radiation. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2017; 37:459-491. [PMID: 28586320 DOI: 10.1088/1361-6498/aa5fc7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this paper we compare the findings of epidemiologic studies of childhood leukemia that examined at least two of ELF magnetic fields and/or distance to power lines, and exposure to radon and gamma radiation or distance to nuclear plants. Many of the methodologic aspects are common to studies of non-ionising (i.e. ELF-MF) and ionising radiation. A systematic search and review of studies with more than one exposure under study identified 33 key and 35 supplementary papers from ten countries that have been included in this review. Examining studies that have looked at several radiation exposures, and comparing similarities and differences for the different types of radiation, through the use of directed acyclic graphs, we evaluate to what extent bias, confounding and other methodological issues might be operating in these studies. We found some indication of bias, although results are not clear cut. There is little evidence that confounding has had a substantial influence on results. Influence of the residential mobility on the study conduct and interpretation is complex and can manifest as a selection bias, confounding, increased measurement error or could also be a potential risk factor. Other factors associated with distance to power lines and to nuclear power plants should be investigated. A more complete and consistent reporting of results in the future studies will allow for a more informative comparison across studies and integration of results.
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Affiliation(s)
- Leeka Kheifets
- University of California Los Angeles, United States of America
| | - John Swanson
- National Grid, 1-3 Strand, London, United Kingdom
| | - Yingzhe Yuan
- University of California Los Angeles, United States of America
| | - Cynthia Kusters
- University of California Los Angeles, United States of America
| | - Ximena Vergara
- University of California Los Angeles, United States of America
- Electric Power Research Institute, Palo Alto, CA, United States of America
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