Epidemiological study (observational study)

A case-control study of childhood leukemia in southern Ontario, Canada, and exposure to magnetic fields in residences epidem.

By: Green LM, Miller AB, Villeneuve PJ, Agnew DA, Greenberg ML, Li J, Donnelly KE

Published in: Int J Cancer 1999; 82 (2): 161-170

Aim of study (acc. to author)

To investigate the association between the risk of childhood leukemia and residential exposure to magnetic fields, a population-based case-control study was conducted in Canada.

Further details

Exposure to magnetic fields was assessed by point-in-time measurements inside and outside the residences and by wire-code classification according to Wertheimer-Leeper, Barnes (Wertheimer-Leeper scheme modified by considering underground service) and Kaune-Savitz.

Endpoint/type of risk estimation

childhood leukemia

Type of risk estimation:

incidence

(odds ratio (OR))

Exposure

Assessment

wire code: Wertheimer-Leeper scheme, Wertheimer-Leeper scheme modified by Barnes, Kaune-Savitz scheme
measurement: point-in-time measurements in the child's bedroom and two other rooms most frequently used by the child, point-in-time measurements outside the home
calculation: time-weighted averages of point-in-time measurements

Exposure groups

Group	Description
Reference group 1	measurement of magnetic flux density in child's bedroom: < 0.03 µT
Group 2	measurement of magnetic flux density in child's bedroom: 0.03 - 0.06 µT
Group 3	measurement of magnetic flux density in child's bedroom: 0.06 - 0.12 µT
Group 4	measurement of magnetic flux density in child's bedroom: ≥ 0.13 µT
Reference group 5	measurement of magnetic flux density, interior average: < 0.04 µT
Group 6	measurement of magnetic flux density, interior average: 0.04 - 0.08 µT
Group 7	measurement of magnetic flux density, interior average: 0.09 - 0.14 µT
Group 8	measurement of magnetic flux density, interior average: ≥ 0.15 µT
Reference group 9	measurement of magnetic flux density, outside: < 0.03 µT
Group 10	measurement of magnetic flux density, outside: 0.03 - 0.07 µT
Group 11	measurement of magnetic flux density, outside: 0.08 - 0.14 µT
Group 12	measurement of magnetic flux density, outside: ≥ 0.15 µT
Reference group 13	Wertheimer-Leeper: very low current configuration (VLCC)
Group 14	Wertheimer-Leeper: ordinary low-current configuration (OLCC)
Group 15	Wertheimer-Leeper: ordinary high-current configuration (OHCC)
Group 16	Wertheimer-Leeper: very-high-current configuration (VHCC)
Reference group 17	Wertheimer-Leeper, modified by Barnes: underground
Group 18	Wertheimer-Leeper, modified by Barnes: very low current configuration (VLCC)
Group 19	Wertheimer-Leeper, modified by Barnes: ordinary low-current configuration (OLCC)
Group 20	Wertheimer-Leeper, modified by Barnes: ordinary high-current configuration (OHCC)
Group 21	Wertheimer-Leeper, modified by Barnes: very-high-current configuration (VHCC)
Reference group 22	Kaune-Savitz: low
Group 23	Kaune-Savitz: medium
Group 24	Kaune-Savitz: high

Population

Group:
- children
Age: 0–14 years
Observation period: 1985 - 1993
Study location: Canada (southern Ontario)

Case group

Characteristics: children with leukemia
Data source: Pediatric Oncology Group Registry

Control group

Selection:
- population-based
Matching:
- sex
- age
- case:control = 1:2

Study size

	Cases	Controls
Eligible	298	1,133
Participants	203	419
Evaluable	201	406

Statistical analysis method:

conditional logistic regression

(adjustment:

)

Results (acc. to author)

Magnetic field exposures measured both inside and outside the residences representing at least 70 % of the etiological period showed weak, non-significant associations with childhood leukemia. For children younger than 6 years at diagnosis, an association between outside perimeter measurements of the residence with magnetic fields of 0.15 µT and above and increased leukemia risk was found. The findings did not support an association between childhood leukemia and proximity to power lines with high current configuration.

Study funded by

Ontario Hydro (Hydro-Electric Power Commission), Canada

Amoon AT et al. (2022): Pooled analysis of recent studies of magnetic fields and childhood leukemia
Seomun G et al. (2021): Exposure to extremely low-frequency magnetic fields and childhood cancer: A systematic review and meta-analysis
Núñez-Enríquez JC et al. (2020): Extremely Low-Frequency Magnetic Fields and the Risk of Childhood B-Lineage Acute Lymphoblastic Leukemia in a City With High Incidence of Leukemia and Elevated Exposure to ELF Magnetic Fields
Auger N et al. (2019): Residential exposure to electromagnetic fields during pregnancy and risk of child cancer: A longitudinal cohort study
Crespi CM et al. (2019): Childhood leukemia risk in the California Power Line Study: Magnetic fields versus distance from power lines
Swanson J et al. (2018): Reanalysis of risks of childhood leukaemia with distance from overhead power lines in the UK
Amoon AT et al. (2018): Proximity to overhead power lines and childhood leukaemia: an international pooled analysis
Kheifets L et al. (2017): Residential magnetic fields exposure and childhood leukemia: a population-based case-control study in California
Bunch KJ et al. (2016): Epidemiological study of power lines and childhood cancer in the UK: further analyses
Crespi CM et al. (2016): Childhood leukaemia and distance from power lines in California: a population-based case-control study
Tabrizi MM et al. (2015): Increased risk of childhood acute lymphoblastic leukemia (ALL) by prenatal and postnatal exposure to high voltage power lines: a case control study in Isfahan, Iran
Salvan A et al. (2015): Childhood Leukemia and 50 Hz Magnetic Fields: Findings from the Italian SETIL Case-Control Study
Pedersen C et al. (2015): Residential exposure to extremely low-frequency magnetic fields and risk of childhood leukaemia, CNS tumour and lymphoma in Denmark
Tabrizi MM et al. (2015): Role of electromagnetic field exposure in childhood acute lymphoblastic leukemia and no impact of urinary alpha-amylase - a case control study in Tehran, Iran
Leitgeb N (2015): Synoptic Analysis Clarifies Childhood Leukemia Risk from ELF Magnetic Field Exposure
Ba Hakim AS et al. (2014): ELF-EMF correlation study on distance from overhead transmission lines and acute leukemia among children in Klang Valley, Malaysia
Swanson J et al. (2014): Childhood cancer and exposure to corona ions from power lines: an epidemiological test
Bunch KJ et al. (2014): Residential distance at birth from overhead high-voltage powerlines: childhood cancer risk in Britain 1962-2008
Zhao L et al. (2014): Magnetic fields exposure and childhood leukemia risk: a meta-analysis based on 11,699 cases and 13,194 controls
Pedersen C et al. (2014): Distance from residence to power line and risk of childhood leukemia: a population-based case-control study in Denmark
Sermage-Faure C et al. (2013): Childhood leukaemia close to high-voltage power lines--the Geocap study, 2002-2007
Schüz J et al. (2012): Extremely low-frequency magnetic fields and survival from childhood acute lymphoblastic leukemia: an international follow-up study
Jirik V et al. (2012): Association between Childhood Leukaemia and Exposure to Power-frequency Magnetic Fields in Middle Europe
Swanson J et al. (2012): Could the geomagnetic field be an effect modifier for studies of power-frequency magnetic fields and childhood leukaemia?
Wünsch Filho V et al. (2011): Exposure to magnetic fields and childhood acute lymphocytic leukemia in Sao Paulo, Brazil
Kroll ME et al. (2010): Childhood cancer and magnetic fields from high-voltage power lines in England and Wales: a case-control study
Sohrabi MR et al. (2010): Living near overhead high voltage transmission power lines as a risk factor for childhood acute lymphoblastic leukemia: a case-control study
Kheifets L et al. (2010): Pooled analysis of recent studies on magnetic fields and childhood leukaemia
Malagoli C et al. (2010): Risk of hematological malignancies associated with magnetic fields exposure from power lines: a case-control study in two municipalities of northern Italy
Rahman HIA et al. (2008): A case-control study on the association between environmental factors and the occurrence of acute leukemia among children in Klang Valley, Malaysia
Svendsen AL et al. (2007): Exposure to magnetic fields and survival after diagnosis of childhood leukemia: a German cohort study
Kabuto M et al. (2006): Childhood leukemia and magnetic fields in Japan: a case-control study of childhood leukemia and residential power-frequency magnetic fields in Japan
Foliart DE et al. (2006): Magnetic field exposure and long-term survival among children with leukaemia
Draper G et al. (2005): Childhood cancer in relation to distance from high voltage power lines in England and Wales: a case-control study
Schüz J et al. (2001): Residential magnetic fields as a risk factor for childhood acute leukaemia: results from a German population-based case-control study
UK Childhood Cancer Study Investigators (2000): Childhood cancer and residential proximity to power lines
Greenland S et al. (2000): A pooled analysis of magnetic fields, wire codes, and childhood leukemia. Childhood Leukemia-EMF Study Group
Ahlbom A et al. (2000): A pooled analysis of magnetic fields and childhood leukaemia
Dockerty JD et al. (1999): Electromagnetic field exposures and childhood leukaemia in New Zealand
Green LM et al. (1999): Childhood leukemia and personal monitoring of residential exposures to electric and magnetic fields in Ontario, Canada
UK Childhood Cancer Study Investigators (1999): Exposure to power-frequency magnetic fields and the risk of childhood cancer
Angelillo IF et al. (1999): Residential exposure to electromagnetic fields and childhood leukaemia: a meta-analysis
McBride ML et al. (1999): Power-frequency electric and magnetic fields and risk of childhood leukemia in Canada
Michaelis J et al. (1998): Combined risk estimates for two German population-based case-control studies on residential magnetic fields and childhood acute leukemia
Dockerty JD et al. (1998): Electromagnetic field exposures and childhood cancers in New Zealand
Linet MS et al. (1997): Residential exposure to magnetic fields and acute lymphoblastic leukemia in children
Tynes T et al. (1997): Electromagnetic Fields and Cancer in Children Residing Near Norwegian High-Voltage Power Lines
Petridou E et al. (1997): Electrical power lines and childhood leukemia: a study from Greece
Feychting M et al. (1993): Magnetic fields and cancer in children residing near Swedish high-voltage power lines
Verkasalo PK et al. (1993): Risk of cancer in Finnish children living close to power lines
Petridou E et al. (1993): Age of exposure to infections and risk of childhood leukaemia
Olsen J et al. (1993): Residence near high voltage facilities and risk of cancer in children
Savitz DA et al. (1988): Case-control study of childhood cancer and exposure to 60-Hz magnetic fields
Fulton JP et al. (1980): Electrical wiring configurations and childhood leukemia in Rhode Island
Wertheimer N et al. (1979): Electrical wiring configurations and childhood cancer