Study type: Medical/biological study (observational study)

Effect of Electromagnetic Field on Serum Biochemical Parameters in Steelworkers med./bio.

Published in: J Occup Health 1999; 41 (3): 177-180

Aim of study (acc. to author)

The effects of a chronic occupational exposure of steelworkers to a 50 Hz magnetic field on blood serum parameters should be investigated.

Background/further details

64 steelworkers employed at the same workplace with chronic occupational exposure were used as "cases" and were divided into the three following groups on the basis of their previous employment period: 1) up to 3 years (n=20, mean age=24.2 ± 6.5 years), 2) 3-10 years (n=28, mean age=36.2 ± 7.2 years) and 3) more than 10 years (n=16, mean age=38.8 ± 8.9 years). The control group (n=25, mean age=35.2 ± 9.9 years) consisted of workers from the same factory in capacities without occupational exposure to a magnetic field. A total of 12 blood samples was taken per subject, 1 sample every 4 weeks.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: repeated daily exposure of 6.8 h/day (mean) from Monday to Friday, a total of 34 h/week for up to >10 years

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Exposure duration repeated daily exposure of 6.8 h/day (mean) from Monday to Friday, a total of 34 h/week for up to >10 years
Exposure setup
Exposure source
Setup subjects worked at a tool shop and heavy processing shop, where two induction heaters were located; shops were closed rooms with appropriate humidity, ventilation and temperature
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 20 V/m - - - -
magnetic field strength 2 A/m - - - -
magnetic flux density 1.3 mT - - - induction-value of each heater, not specified

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

The total protein level was significantly decreased in group 2 (exposed for 3-10 years), the β-globulin level was significantly decreased in all case groups and the γ-globulin level was significantly decreased in group 1 (exposed for up to 3 years) and group 2 compared to the control. The enzyme activity of aspartate aminotransferase was significantly increased, whereas gamma-glutamyltranspeptidase and malate dehydrogenase activities were significantly reduced in group 3 (exposed for more than 10 years) compared to the control. The total lipid level and the total cholesterol levels were both significantly decreased in groups 2 and 3 compared to the control. Moreover, the triglycerides and pre-β-lipoproteins levels were significantly decreased and the α-lipoproteins level significantly increased in group 3 compared to the control.
The authors conclude, that a chronic occupational exposure of steelworkers to a 50 Hz magnetic field could influence some blood serum parameters. The most distinct changes were found in workers who had been occupationally exposed for more than 10 years.

Study character:

Study funded by

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