Leukemia following Occupational Exposure to 60-Hz Electric and Magnetic Fields among Ontario Electric Utility Workers

Abstract

In a nested case-control study of 1,484 cancer cases and 2,179 matched controls from a cohort of 31,543 Ontario Hydro male employees, the authors evaluated associations of cancer risk with electric field exposure and reevaluated the previously reported findings for magnetic fields. Pensioners were followed from January 1, 1970, and active workers (including those who left the corporation) from January 1, 1973, with both groups followed through December 31, 1988. Exposures to electric and magnetic fields and to potential occupational confounders were estimated through job exposure matrices. Odds ratios were elevated for hematopoietic malignancies with cumulative electric field exposure. After adjustment, the odds ratio for leukemia in the upper tertile was 4.45 (95% confidence interval (CI) 1.01-19.7). Odds ratios were also elevated for acute nonlymphoid leukemia, acute myeloid leukemia, and chronic lymphoid leukemia. For cumulative magnetic field exposure, there were similar elevations that fell with adjustment. Evaluation of the combined effect of electric and magnetic fields for leukemia showed significant elevations of risk for high exposure to both, with a dose-response relation for increasing exposure to electric fields and an inconsistent effect for magnetic fields. There was some evidence of a nonsignificant association for brain cancer and benign brain tumors with magnetic fields. For lung cancer, the odds ratio for high exposure to electric and magnetic fields was 1.84 (95% CI 0.69-4.94).

Occupational exposure and cancer incidence among workers from an aluminum smelter in western Norway

“…Employment in "electrical occupations" has repeatedly been associated with increased risk (20), whereas studies based on quantitative exposure estimates have produced negative or equivocal results (21)(22)(23)(24). In the present study the absence of an association with magnetic field exposure in the production cohort was contrasted by a statistically significant, positive association with employment as a maintenance electrician.…”

The non-Hodgkin lymphomas: A review of the epidemiologic literature

“…Occupational exposure to electromagnetic fields was not significantly associated with risk of NHL in some studies, [358][359][360] although an inverse association was reported among workers with high-intensity exposure in one study. 170 Neither the latter study nor one other provided evidence of a doseresponse relationship between NHL risk and increasing electromagnetic radiation exposure, based on intensity of potential exposure and cumulative exposure level.…”

“…170 Neither the latter study nor one other provided evidence of a doseresponse relationship between NHL risk and increasing electromagnetic radiation exposure, based on intensity of potential exposure and cumulative exposure level. 170,358 In a Canadian study of electric utility workers, the authors evaluated the risk of NHL based on percentage of time above a specified threshold of electric field and magnetic field exposure. 361 Significant positive associations were found for the upper tertile of percentage of time spent above electric field intensities of 10 (OR 5 3.05, 95% CI: 1.07-8.80) and 40 (OR 5 3.57, 95% CI: 1.30-9.80) Volts per meter, but the strength of association diminished and was no longer significant among higher intensity categories.…”

The 1.5 GHz Electromagnetic Near‐field Used for Cellular Phones Does Not Promote Rat Liver Carcinogenesis in a Medium‐term Liver Bioassay

“…[1][2][3][4][5] This may be particularly the case for industrial high exposure to electric and/or magnetic fields, derived not only from 50 or 60 Hz power frequency sources, but also from high-frequency transmitters. 6,7) Equivocal evidence of increased risk of brain tumors and leukemia development has been presented. [8][9][10][11][12][13] The use of portable cellular phones is rapidly expanding in many countries, and the potential health hazards to humans of the electromagnetic waves that they use is therefore of great concern.…”