Study type: Epidemiological study (observational study)

A cross-sectional study on oxidative stress in workers exposed to extremely low frequency electromagnetic fields epidem.

Published in: Int J Radiat Biol 2015; 91 (5): 420-425

Aim of study (acc. to author)

A cross-sectional study was conducted in China to investigate whether exposure to extremely low frequency magnetic fields could induce oxidative stress in workers regularly performing inspection tours close to voltage transformers and distribution power lines.

Endpoint/type of risk estimation

Type of risk estimation:

Exposure

Assessment

Exposure groups

Group Description
Reference group 1 administrative staff: no exposure
Group 2 duration of magnetic field exposure: < 5 years
Group 3 duration of magnetic field exposure: ≥ 5 years
Reference group 4 8 h time-weighted average magnetic field strength: < 1.56 µT
Group 5 8 h time-weighted average magnetic field strength: 1.56 - 7.3 µT
Group 6 8 h time-weighted average magnetic field strength: > 7.3 µT

Population

Study size

Type Value
Total 700
Evaluable 560
Statistical analysis method:

Results (acc. to author)

In the 500 kV and 220 kV areas, the magnetic flux density at the spots ranged from 0.62-30.19 µT (median 18.7 µT) and from 0.51-60.11 µT (median 17.7 µT), respectively. In comparison, the magnetic flux density ranged from 0.07 to 0.72 µT with a median of 0.21 µT in the environment of the administrative staff. The 8 h time-weighted average magnetic flux density of the workers was 7.3 µT (1.56-26.3 µT).
No significant changes of the investigated oxidative stress parameters were found between workers that regularly perform inspection tours close to voltage transformers and distribution power lines and administrative staff.
The authors conclude that continual exposure to extremely low frequency electromagnetic fields might not induce oxidative stress in workers from a power supply company.

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