Medical/biological study (experimental study)

Sinusoidal 50 Hz, 500 microT magnetic field has no acute effect on urinary 6-sulphatoxymelatonin in Wistar rats med./bio.

By: Bakos J, Nagy N, Thuroczy G, Szabo LD

Published in: Bioelectromagnetics 1995; 16 (6): 377-380

Aim of study (acc. to author)

To investigate the effect of a 50 Hz magnetic field (MF) exposure on melatonin production in rats.

Background/further details

6-sulphatoxymelatonin is the major metabolite of melatonin and can be determined easily non-invasively in excreted urine.
A total of 20 adult rats were used (10 male and 10 female, divided into 2 groups: magnetic field-exposed (500 µT) and sham exposed (5 µT, stray field)). A light (9 h)/dark (15 h) cycle was maintained (light on at 7 a.m./light off at 4 p.m.). Urine was collected twice a day (i.e. at the end of the dark phase and light phase, respectively) over a period of 5 consecutive days. The magnetic field was turned on at 7 a.m. on day 3 and turned off at 7 a.m. on day 4 (total magnetic field exposure time 24 h).

Endpoint

endocrine changes: melatonin metabolism

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: 24 h	magnetic flux density: 5 µT effective value (cage located in the stray field) magnetic flux density: 500 µT effective value (at the center of the cage)

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	24 h

Exposure setup

Exposure source	pair of doublewound coils connected with a special AC generator
Chamber	Metabolic cages/ 20 cm in diameter, 11 cm high.
Setup	Cages kept in the center of the coils.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	5 µT	effective value	measured	-	cage located in the stray field
magnetic flux density	500 µT	effective value	measured	-	at the center of the cage

Additional parameter details

Geomagnetic field was 48 µT.

Exposed system:

animal
rat/Wistar
whole body

Methods Endpoint/measurement parameters/methodology

endocrine changes: amount of 6-sulphatoxymelatonin in excreted urine (radioimmunoassay)

Investigated system:

isolated bio./chem. substance
6-sulphatoxymelatonin
investigation on living organism

Time of investigation:

before exposure
during exposure
after exposure

Main outcome of study (acc. to author)

No significant changes in the excretion of 6-sulphatoxymelatonin during or after magnetic field exposure could be observed.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

not stated/no funding

Replication studies

Bakos J et al. (1997): Urinary 6-sulphatoxymelatonin excretion is increased in rats after 24 hours of exposure to vertical 50 Hz, 100 microT magnetic field

Seifpanahi-Shabani H et al. (2016): Long-term Exposure to Extremely Low Frequency Electromagnetic Field and Melatonin Production by Blood Cells
Dyche J et al. (2012): Effects of power frequency electromagnetic fields on melatonin and sleep in the rat
Davis S et al. (2006): Effects of 60-Hz magnetic field exposure on nocturnal 6-sulfatoxymelatonin, estrogens, luteinizing hormone, and follicle-stimulating hormone in healthy reproductive-age women: results of a crossover trial
Gobba F et al. (2006): No association between occupational exposure to ELF magnetic field and urinary 6-sulfatoximelatonin in workers
Bakos J et al. (2002): One week of exposure to 50 Hz, vertical magnetic field does not reduce urinary 6-sulphatoxymelatonin excretion of male wistar rats
Chacon L (2000): 50-Hz Sinusoidal Magnetic Field Effect On In Vitro Pineal N-Acetyltransferase Activity
Heikkinen P et al. (1999): Chronic exposure to 50-Hz magnetic fields or 900-MHz electromagnetic fields does not alter nocturnal 6-hydroxymelatonin sulfate secretion in CBA/S mice
Selmaoui B et al. (1999): Age-related differences in serum melatonin and pineal NAT activity and in the response of rat pineal to a 50-Hz magnetic field
Bakos J et al. (1999): Urinary 6-Sulphatoxymelatonin Excretion of Rats is not Changed by 24 Hours of Exposure to A Horizontal 50-Hz, 100-μT Magnetic Field
Bakos J et al. (1997): Urinary 6-sulphatoxymelatonin excretion is increased in rats after 24 hours of exposure to vertical 50 Hz, 100 microT magnetic field