|Additional info||The exposed group comprised of 63 male technical service workers, aged 22-67 years, at four substations. The control group consisted of of 42 male technical service workers, aged 20-68 years, at four radio link stations.|
The relative risk of decreased heart rate variability was significantly higher in the exposed group than in controls. The very low frequency power spectrum was significantly higher in the exposed group and correlated with the exposure level. The percentage of subjects with dominant sympathetic function was significantly higher in the study group than in controls (65% vs. 47%).
It was concluded that occupational exposure to 50 Hz electromagentic fields could influence the neurovegetative regulation of the cardiovascular system.