Medical/biological study (observational study)

Long-term (up to 20 years) effects of 50-Hz magnetic field exposure on immune system and hematological parameters in healthy men med./bio.

By: Touitou Y, Djeridane Y, Lambrozo J, Camus F, Selmaoui B

Published in: Clin Biochem 2013; 46 (1-2): 59-63

Aim of study (acc. to author)

To study the effects of an exposure to electromagnetic fields in workers chronically exposed to electromagnetic fields both at work and at home (between 1 and 20 years duration) on immunological-hematological parameters (q.v. Touitou et al. 2012).

Background/further details

The exposed volunteers (n=15) worked in substations and their main tasks included installing couplings between extra high voltage lines and voltage transformers. Moreover, the exposed subjects lived near the substations.
None of the controls had a professional position that could have resulted in occupational exposure to magnetic fields. They were subjected only to the normal electromagnetic fields of our daily environment.
All subjects were synchronized with daytime activity from 7:00 h to 23:00 h and nocturnal rest.
Blood samples were taken hourly from 20.00 h -8:00 h.

Endpoint

effects on the immune system: immunological-hematological parameters

Exposure

- 50/60 Hz
- magnetic field
- electrical substation
- occupational
- residential

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: continuous for up to 20 years (10 workers: 7-20 years; 5 workers: 1-4 years)	magnetic flux density: 0.72 µT mean (of 15 workers) magnetic flux density: 0.64 µT mean (daytime (occupational exposure)) magnetic flux density: 0.82 µT mean (nighttime (residential)) magnetic flux density: 2.6 µT maximum (geometric mean (individual exposure))

Exposure 1

Main characteristics

Frequency	50 Hz
Exposure duration	continuous for up to 20 years (10 workers: 7-20 years; 5 workers: 1-4 years)

Exposure setup

Exposure source	substations (occupational exposure) and power lines (residential exposure)
Additional info	extra high voltage substations (occupational) and power lines (residential exposure) of a 225 kV and 400 kV electricity transmission network

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	0.72 µT	mean	calculated	-	of 15 workers
magnetic flux density	0.64 µT	mean	calculated	-	daytime (occupational exposure)
magnetic flux density	0.82 µT	mean	calculated	-	nighttime (residential)
magnetic flux density	2.6 µT	maximum	measured	-	geometric mean (individual exposure)

Additional parameter details

a subset of 3 subjects had an arithmetic mean of 2.1 µT (workday arithmetic mean of 1.5 µT and nighttime residential exposure of 2.71 µT); arithmetic mean of the controls was 0.04 µT (also the arithmetic mean of both the workday and nighttime exposure was 0.04 µT)

Measurement and calculation details

all subjects wore a personal dosimeter; magnetic field measurements were recorded for 7 days during daytime and at night (every 30 s)

Exposed system:

human
whole body

Methods Endpoint/measurement parameters/methodology

effects on the immune system: immunological-hematological parameters (red blood cells, hemoglobin, hematocrit, platelets, white blood cells, lymphocytes, monocytes, eosinophils, basophils, neutrophils, IgA, IgM, IgG, CD3, CD4, CD8, natural killer cells, B cells, CD28, CD8+ CD28+, activated T cells, IL-2, IL-6, IL-2 receptor; immunofluorescence; fluorescence microscopy; flow cytometry; immunoassay; blood cell analyzer)

Investigated system:

blood samples

Investigated organ system:

immune system
hematological system

Time of investigation:

during exposure

Main outcome of study (acc. to author)

The data showed that a long-term chronic exposure to 50 Hz magnetic fields did not affect the hematological and immune system functions or their profiles in healthy men, at least for the variables studied. Thus, the data suggest that magnetic fields have no cumulative effects on these functions.

Study character:

medical/biological study
observational study
blind study

Study funded by

Electricité de France (EDF)
Réseau de Transport d'Electricité (RTE), France

Touitou Y et al. (2022): Assessment of cortisol secretory pattern in workers chronically exposed to ELF-EMF generated by high voltage transmission lines and substations
Touitou Y et al. (2020): Evaluation in humans of ELF-EMF exposure on chromogranin A, a marker of neuroendocrine tumors and stress
Molaei S et al. (2019): Effect of 50-Hz Magnetic Fields on Serum IL-1β and IL-23 and Expression of BLIMP-1, XBP-1, and IRF-4
Sobhanifard M et al. (2019): Effect of Extremely Low Frequency Electromagnetic Fields on Expression of T-bet and GATA-3 Genes and Serum Interferon-γ and Interleukin-4
Mahdavinejad L et al. (2018): Extremely Low Frequency Electromagnetic Fields Decrease Serum Levels of Interleukin-17, Transforming Growth Factor-β and Downregulate Foxp3 Expression in the Spleen
Zhang D et al. (2017): Resveratrol may reverse the effects of long-term occupational exposure to electromagnetic fields on workers of a power plant
Tiwari R et al. (2013): The Potential Bioeffects of Extremely Low Frequency Electromagnetic Fields on Melatonin Levels & Related Oxidative Stress in Electric Utility Workers Exposed to 132 kV Substation
Touitou Y et al. (2012): Long-term (up to 20 years) effects of 50-Hz magnetic field exposure on blood chemistry parameters in healthy men
Selmaoui B et al. (2011): Acute exposure to 50-Hz magnetic fields increases interleukin-6 in young healthy men
Gobba F et al. (2009): Natural killer cell activity decreases in workers occupationally exposed to extremely low frequency magnetic fields exceeding 1 microT
Gobba F et al. (2009): Extremely low frequency-magnetic fields (ELF-EMF) occupational exposure and natural killer activity in peripheral blood lymphocytes
Di Giampaolo L et al. (2006): Follow up study on the immune response to low frequency electromagnetic fields in men and women working in a museum
Ichinose TY et al. (2004): Immune markers and ornithine decarboxylase activity among electric utility workers
Bonhomme-Faivre L et al. (2003): Effects of electromagnetic fields on the immune systems of occupationally exposed humans and mice
Dasdag S et al. (2002): Effects of extremely low frequency electromagnetic fields on hematologic and immunologic parameters in welders
Tuschl H et al. (2000): Occupational exposure to static, ELF, VF and VLF magnetic fields and immune parameters
Kula B et al. (1999): Effect of Electromagnetic Field on Serum Biochemical Parameters in Steelworkers
Selmaoui B et al. (1999): Assessment of the effects of nocturnal exposure to 50-Hz magnetic fields on the human circadian system. A comprehensive study of biochemical variables
Tuschl H et al. (1999): Occupational exposure to high frequency electromagnetic fields and its effect on human immune parameters
Mevissen M et al. (1998): Complex effects of long-term 50 Hz magnetic field exposure in vivo on immune functions in female Sprague-Dawley rats depend on duration of exposure
Bonhomme-Faivre L et al. (1998): Study of human neurovegetative and hematologic effects of environmental low-frequency (50-Hz) electromagnetic fields produced by transformers
Selmaoui B et al. (1996): Acute exposure to 50 Hz magnetic field does not affect hematologic or immunologic functions in healthy young men: a circadian study