Epidemiological study (observational study)

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. epidem.

By: Tabrizi MM, Bidgoli SA

Published in: Asian Pac J Cancer Prev 2015; 16 (6): 2347-2350

Aim of study (acc. to author)

A case-control study was conducted in Iran to investigate the role of prenatal and postnatal exposure to high voltage power lines and other risk factors on the incidence of childhood acute lymphoblastic leukemia.

Further details

Remark EMF-Portal: Number of cases and controls as well as study results and whole chapters of this publication are identical in the publication by Tabrizi and Hosseini (2015). It is unclear whether this is a replication study with the same results or two studies conducted in two different cities with the same results.
Details of exposure assessment are missing in this publication. It is not stated how 'living near high voltage power lines' is defined and how the exposure to power lines was classified into 'yes' or 'no'.

Endpoint/type of risk estimation

childhood leukemia: acute lymphoblastic leukemia

Type of risk estimation:

incidence

(odds ratio (OR))

Exposure

- 50/60 Hz
- magnetic field
- also other exposures without EMF
- power transmission line
- residential

Assessment

questionnaire: living near high voltage power lines, using mobile phones, computers, microwave and all indoor electrically charged objects

Exposure groups

Group	Description
Reference group 1	prenatal exposure to power lines: no
Group 2	prenatal exposure to power lines: yes
Reference group 3	postnatal exposure to power lines: no
Group 4	postnatal exposure to power lines: yes

Population

Group:
- children
- children in utero
Age: 0–11 years
Observation period: 2013 - 2014
Study location: Iran (Isfahan)

Case group

Exclusion criteria: lack of access to the parents, birth and living out of Isfahan, having moderate and higher socioeconomic status

Control group

Matching:
- area
- 5-year age group

Study size

	Cases	Controls
Evaluable	22	100

Statistical analysis method:

Chi-square test
t-test, Cochrane-Mantel-Haenszel test

Conclusion (acc. to author)

Overall, 4 out of 22 (18.8%) of children with acute lymphoblastic leukemia and 3 out of 100 control children were exposed to high voltage power lines. As the population study was from low socioeconomic status, use of mobile phones, computers and microwave ovens was negligible.
Prenatal and childhood exposure to high voltage power lines was considered as the most important environmental risk factors of acute lymphoblastic leukemia (OR 3.65, CI 1.69-7.88).
The authors concluded that prenatal and postnatal exposure to high voltage power lines and living in pollutant regions as well as familial history of leukemia and parental occupational exposure to chemicals and radiation could be described as risk factors of childhood acute lymphoblastic leukemia for the first time in a low socioeconomic status Iranian population.

Limitations (acc. to author)

The results are based on low numbers.

Comments on this article

Dechent D et al. (2016): Re: Role of Electromagnetic Field Exposure in Childhood Acute Lymphoblastic Leukemia and No Impact of Urinary Alpha- Amylase - a Case Control Study in Tehran, Iran.

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.
Crespi CM et al. (2019): Childhood leukemia risk in the California Power Line Study: Magnetic fields versus distance from power lines.
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): Role of electromagnetic field exposure in childhood acute lymphoblastic leukemia and no impact of urinary alpha-amylase - a case control study in Tehran, Iran.
Pedersen C et al. (2015): Residential exposure to extremely low-frequency magnetic fields and risk of childhood leukaemia, CNS tumour and lymphoma in Denmark.
Salvan A et al. (2015): Childhood Leukemia and 50 Hz Magnetic Fields: Findings from the Italian SETIL Case-Control Study.
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.
Bunch KJ et al. (2014): Residential distance at birth from overhead high-voltage powerlines: childhood cancer risk in Britain 1962-2008.
Swanson J et al. (2014): Childhood cancer and exposure to corona ions from power lines: an epidemiological test.
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.
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.
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.
Kroll ME et al. (2010): Childhood cancer and magnetic fields from high-voltage power lines in England and Wales: a case-control study.
Kheifets L et al. (2010): Pooled analysis of recent studies on magnetic fields and childhood leukaemia.
Kheifets L et al. (2010): A Pooled Analysis of Extremely Low-Frequency Magnetic Fields and Childhood Brain Tumors.
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.
Yang Y et al. (2008): Case-only study of interactions between DNA repair genes (hMLH1, APEX1, MGMT, XRCC1 and XPD) and low-frequency electromagnetic fields in childhood acute leukemia.
Mezei G et al. (2008): Residential Magnetic Field Exposure and Childhood Brain Cancer: A Meta-Analysis.
Lowenthal RM et al. (2007): Residential exposure to electric power transmission lines and risk of lymphoproliferative and myeloproliferative disorders: a case-control study.
Swanson J et al. (2006): Power-frequency electric and magnetic fields in the light of Draper et al. 2005.
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.
Draper G et al. (2005): Childhood cancer in relation to distance from high voltage power lines in England and Wales: a case-control study.
UK Childhood Cancer Study Investigators (2000): Childhood cancer and residential proximity to power lines.
Kleinerman RA et al. (2000): Are children living near high-voltage power lines at increased risk of acute lymphoblastic leukemia?
Bianchi N et al. (2000): Overhead electricity power lines and childhood leukemia: a registry-based, case-control study.
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.
McBride ML et al. (1999): Power-frequency electric and magnetic fields and risk of childhood leukemia in Canada.
Green LM et al. (1999): Childhood leukemia and personal monitoring of residential exposures to electric and magnetic fields in Ontario, Canada.
Angelillo IF et al. (1999): Residential exposure to electromagnetic fields and childhood leukaemia: a meta-analysis.
UK Childhood Cancer Study Investigators (1999): Exposure to power-frequency magnetic fields and the risk of childhood cancer.
Green LM et al. (1999): A case-control study of childhood leukemia in southern Ontario, Canada, and exposure to magnetic fields in residences.
Michaelis J et al. (1998): Combined risk estimates for two German population-based case-control studies on residential magnetic fields and childhood acute leukemia.
Michaelis J et al. (1997): Childhood leukemia and electromagnetic fields: results of a population-based case-control study in Germany.
Linet MS et al. (1997): Residential exposure to magnetic fields and acute lymphoblastic leukemia in children.
Petridou E et al. (1997): Electrical power lines and childhood leukemia: a study from Greece.
Tynes T et al. (1997): Electromagnetic Fields and Cancer in Children Residing Near Norwegian High-Voltage Power Lines.
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.
Myers A et al. (1990): Childhood cancer and overhead powerlines: a case-control study.
Coleman MP et al. (1989): Leukaemia and residence near electricity transmission equipment: a case-control study.