Electromagnetic fields and human endocrine system.

Extremely low frequency electromagnetic fields (ELF EMF) are commonly present in daily life all over the world. Moreover, EMF are used in the physiotherapy of many diseases because of their beneficial effects. There is widespread public concern that EMF may have potential consequences for human health. Although experimental animal studies indicate that EMF may influence secretion of some hormones, the data on the effects of EMF on human endocrine system are scarce. Most of the results concentrate on influence of EMF on secretion of melatonin. In this review, the data on the influence of EMF on human endocrine system are briefly presented and discussed. KEYWORDS: electromagnetic fields, endocrine system, hormones DOMAINS: microscopy, medicine, endocrinology, sport medicine and physiotherapy. INTRODUCTION Extremely low frequency electromagnetic fields (ELF EMF) are commonly present in daily life all over the world. They are associated with the use of electric power applied in residential and occupational environments. Wherever electricity is generated, transmitted, or used, electric and magnetic fields are created due to the presence of motion of electric charges. They are emitted by power lines, electrical panels, transformers, and service wires, but also by such household appliances as televisions, electric blankets, hair driers, etc. [1]. Moreover, electromagnetic fields (EMF) are used in the physiotherapy of many diseases (e.g., low back pain syndrome, migraine and vasomotoric headaches, multiple sclerosis, degenerative processes of the bones and joints, rheumatoid arthritis) because of their beneficial effects (e.g., improvement of soft tissue regeneration processes, vasodilatory action, acceleration of bone adhesion formation, anti-inflammatory and analgesic action) There is widespread public concern that EMF may have potential consequences for human health [1, Although there is still scientific controversy concerning that problem, it seems to be a growing consensus that human health hazard associated with exposure to EMF is either very small or restricted to small subgroups. A Working Group organized by the National Institute of Environmental Health Services concluded in a report published in 1998, on the basis of almost 900 publications, that: "None of the evidence for adverse health effects seen after exposure to ELF EMF achieved a degree of evidence exceeding 'inadequate' (for humans) or 'weak' (for experimental animals)" [1]. Studies on the effects of EMF in humans concentrate mainly on power line frequency fields or fields used in mobile phones. The influence of ELF EMF used in physiotherapy on the endocrine system was rarely examined. Although experimental animal studies indicate that EMF may influence secretion of some hormones ELECTROMAGNETIC FIELDS AND MELATONIN The data on the influence of EMF on melatonin secretion in humans are controversial. Although EMFinduced suppression on nocturnal melatonin secretion has been reported in occupational and residential studies ELECTROMAGNETIC FIELDS AND PITUITARY HORMONES No significant effects of EMF on the secretion of growth hormone and FSH have been found ELECTROMAGNETIC FIELDS AND PITUITARY -THYROID AXIS Generally, EMF did not significantly influence hormones secreted by pituitary -thyroid axis 24 Karasek and Woldanska-Okonska: EMFs and hormones TheScientificWorldJOURNAL (2004) 4(S2), 23-28 ELECTROMAGNETIC FIELDS AND PITUITARY -ADRENAL AXIS Electromagnetic fields did not influence secretion of ACTH 25 Karasek and Woldanska-Okonska: EMFs and hormones TheScientificWorldJOURNAL (2004) 4(S2), 23-28 ELECTROMAGNETIC FIELDS AND GONADAL HORMONES In men, chronic application of 2.9 mT, 40 200 Hz EMF[42] or acute exposure to EMF of 1 µT, 50 Hz[30] did not affect testosterone concentrations. However, application of EMF of 25-80 µT, 200 Hz lowered levels of estradiol, whereas EMF of 2.9 mT, 40 Hz have no effect in me