Risk of cancer in Finnish children living close to power lines

BMJ. 1993 Oct 9;307(6909):895-9. doi: 10.1136/bmj.307.6909.895.


Objective: To investigate the risk of cancer in children living close to overhead power lines with magnetic fields of > or = 0.01 microteslas (microT).

Design: Cohort study.

Setting: The whole of Finland.

Subjects: 68,300 boys and 66,500 girls aged 0-19 years living during 1970-89 within 500 m of overhead power lines of 110-400 kV in magnetic fields calculated to be > or = 0.01 microT. Subjects were identified by record linkages of nationwide registers.

Main outcome measures: Numbers of observed cases in follow up for cancer and standardised incidence ratios for all cancers and particularly for nervous system tumours, leukaemia, and lymphoma.

Results: In the whole cohort 140 cases of cancer were observed (145 expected; standardised incidence ratio 0.97, 95% confidence interval 0.81 to 1.1). No statistically significant increases in all cancers and in leukaemia and lymphoma were found in children at any exposure level. A statistically significant excess of nervous system tumours was found in boys (but not in girls) who were exposed to magnetic fields of > or = 0.20 microT or cumulative exposure of > or = 0.40 microT years.

Conclusions: Residentia magnetic fields of transmission power lines do not constitute a major public health problem regarding childhood cancer. The small numbers do not allow further conclusions about the risk of cancer in stronger magnetic fields.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Cohort Studies
  • Electromagnetic Fields / adverse effects*
  • Environmental Exposure
  • Female
  • Finland / epidemiology
  • Housing*
  • Humans
  • Incidence
  • Infant
  • Infant, Newborn
  • Male
  • Neoplasms / epidemiology
  • Neoplasms / etiology*
  • Residence Characteristics
  • Risk Factors