Home
Epidemiological study (observational study)

Residential magnetic fields exposure and childhood leukemia: a population-based case-control study in California.

Published in: Cancer Causes Control 2017

Aim of study (acc. to author)

A case-control study was conducted in the USA to investigate the association between childhood leukemia risk and exposure to magnetic fields from power lines. The previous study by Crespi et al. (2016) based on the distance from birth address to nearby power lines was reanalyzed with improved exposure assessment by calculating magnetic fields based on detailed information.

Endpoint/type of risk estimation

Type of risk estimation:
  • incidence
(odds ratio (OR))

Exposure

Assessment

Exposure groups

Reference group 1 magnetic flux density: < 0.1 µT
Group 2 magnetic flux density: ≥ 0.1 - < 0.2 µT
Group 3 magnetic flux density: ≥ 0.2 - < 0.4 µT
Group 4 magnetic flux density: ≥ 0.4 µT

Population

  • Group:
    • children
  • Age: 0–16 years
  • Observation period: 1988 - 2008
  • Study location: USA (California)

Case group

Control group

  • Selection:
    • population-based
  • Matching:
    • sex
    • age
    • case:control = 1:1
  • Exclusion criteria: diagnosis of any type of cancer

Study size

Cases Controls
Total 6,645 -
Evaluable 5,788 5,788
Statistical analysis method:
  • unconditional logistic regression
  • conditional logistic regression
  • sensitivity analyses, cubic spline analysis
( adjustment: )

Conclusion (acc. to author)

A slight risk deficit for childhood leukemia in two intermediate exposure groups (groups 2 and 3) and a small excess risk in the highest exposure group were observed (OR 1.50, CI 0.70-3.23; unconditional logistic regression controlling for age, sex, race/ethnicity and socioeconomic status). Subgroup and sensitivity analyses as well as matched analyses gave similar results. All results were not statistically significant.
The authors conclude that the results do not provide clear evidence of risk for childhood leukemia associated with greater exposure to magnetic fields from power lines, but could be viewed as consistent with previous findings of increased risk.

Study funded by

  • Electric Power Research Institute (EPRI), USA
  • National Institute of Environmental Health Sciences/National Institute of Health (NIEHS/NIH), USA

Related articles