Mobile phone base stations and early childhood cancers: case-control studyBMJ 2010; 340 doi: http://dx.doi.org/10.1136/bmj.c3077 (Published 22 June 2010) Cite this as: BMJ 2010;340:c3077
- Paul Elliott, professor of epidemiology and public health medicine, head of department, director, MRC-HPA centre for environment and health,
- Mireille B Toledano, senior lecturer in epidemiology,
- J Bennett, research fellow,
- L Beale, research fellow,
- K de Hoogh, senior research officer,
- N Best, professor of statistics and epidemiology,
- D J Briggs, professor, chair in environmental and health sciences, school of public health
- 1Small Area Health Statistics Unit, MRC-HPA Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, St Mary’s Campus, London W2 1PG
- Correspondence to: P Elliott
- Accepted 23 April 2010
Objective To investigate the risk of early childhood cancers associated with the mother’s exposure to radiofrequency from and proximity to macrocell mobile phone base stations (masts) during pregnancy.
Design Case-control study.
Setting Cancer registry and national birth register data in Great Britain.
Participants 1397 cases of cancer in children aged 0-4 from national cancer registry 1999-2001 and 5588 birth controls from national birth register, individually matched by sex and date of birth (four controls per case).
Main outcome measures Incidence of cancers of the brain and central nervous system, leukaemia, and non-Hodgkin’s lymphomas, and all cancers combined, adjusted for small area measures of education level, socioeconomic deprivation, population density, and population mixing.
Results Mean distance of registered address at birth from a macrocell base station, based on a national database of 76 890 base station antennas in 1996-2001, was similar for cases and controls (1107 (SD 1131) m v 1073 (SD 1130) m, P=0.31), as was total power output of base stations within 700 m of the address (2.89 (SD 5.9) kW v 3.00 (SD 6.0) kW, P=0.54) and modelled power density (−30.3 (SD 21.7) dBm v −29.7 (SD 21.5) dBm, P=0.41). For modelled power density at the address at birth, compared with the lowest exposure category the adjusted odds ratios were 1.01 (95% confidence interval 0.87 to 1.18) in the intermediate and 1.02 (0.88 to 1.20) in the highest exposure category for all cancers (P=0.79 for trend), 0.97 (0.69 to 1.37) and 0.76 (0.51 to 1.12), respectively, for brain and central nervous system cancers (P=0.33 for trend), and 1.16 (0.90 to 1.48) and 1.03 (0.79 to 1.34) for leukaemia and non-Hodgkin’s lymphoma (P=0.51 for trend).
Conclusions There is no association between risk of early childhood cancers and estimates of the mother’s exposure to mobile phone base stations during pregnancy.
We are grateful to Les Barclay, David Bacon, and Michael Willis who advised on exposure aspects of the study; Clair Chilvers for advice on study design; Margaret Douglass, Peter Hambly, Catherine Keshishian and Chloe Morris for their help with data extraction and checking; Nirupa Dattani, Gloria Brackett, Nicola Cooper (Office for National Statistics), Ian Brown (General Register Office Scotland), Fiona Campbell, and Lesley Bhatti (Scottish Information and Statistics Division) for their help with checking cancer cases, obtaining birth controls, and data linkage.
Contributors: PE and DJB conceived the study and obtained funding. DJB was responsible for the fieldwork. LB and KdH carried out the geographical information system analysis. MBT was responsible for the data extractions, linkage, and checking. JB and MBT carried out the data analysis under the supervision of NB, DJB, and PE. PE, MT, JB, KdH, and DJB interpreted the results and drafted the paper. All authors approve the final draft of the paper. PE is guarantor.
Funding: The study was funded through the UK Mobile Telecommunications Health Research (MTHR) Programme (www.mthr.org.uk), an independent body set up to provide funding for research into the possible health effects of mobile telecommunications. The MTHR is jointly funded by the UK Department of Health and the mobile telecommunications industry. Members of the independent MTHR programme management committee approved the study design and commented on a draft manuscript. Data collection and analysis, interpretation of data, and the decision to submit the paper for publication were the sole responsibility of the authors.
Competing interests: MBT, JB, LB, KdH, and NB declare that the answers to the questions on the Unified Competing interest form at www.icmje.org/coi_discolure.pdf are all No and therefore declare that they have no conflicts of interest. PE and DJB obtained funding in support of this work from MTHR. PE was a member of the MTHR programme management committee.
Ethical approval: The study was approved by the St Mary’s NHS Trust local research ethics committee.
Data sharing: A technical appendix describing the derivation of modelled power density in more detail is available from the corresponding author.
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