Dimida A, Ferrarini E, Agretti P, De Marco G, Grasso L, Martinelli M, Longo I, Giulietti D, Ricci A, Galimberti M, Siervo B, Licitra G, Francia F, Pinchera A, Vitti P, Tonacchera M. Electric and magnetic fields do not modify the biochemical properties of FRTL-5 cells. J Endocrinol Invest. Ahead of print. Jun 11, 2010.
Numerous scientific studies have been carried out to address the question of whether electric and magnetic fields (EMF) might be involved in human disease. Studies exploring alterations in thyroid structure and function in response to exposure to non-ionizing radiation have been conducted however; no consistent pattern of biological effects has emerged from laboratory studies with animals or with cells.
The objective of this study was to determine the effects of EMF on the thyroid, in particular the effects caused by exposure to a GSM signal (900 MHz) on cultured thyroid cells (FRTL-5).
An epithelial monoclonal continuous cell line derived from Fisher rat thyroid tissue growing as a monolayer (FRTL-5) that expresses the TSH receptor and the sodium-iodide symporter was used in the exposure. A Wire Patch Cell (WPC) which allows samples to be held in a region characterized by homogeneous electromagnetic field values was placed inside a CO2 incubator to guarantee the necessary environmental conditions (temperature, humidity and CO2 concentration) to maintain cells. An RF signal was obtained by amplifying the output of a signal generator. Cells were irradiated for 24, 48 and 96 hours with EMF (800-900 MHz, power-frequency of mobile communication systems) and iodide uptake and cAMP production were measured.
The irradiation of cells with EMF at 900Mhz for 24, 48 and 96 hours did not influence the level of cAMP production and was not able to modify iodide accumulation in FRTL5 cells with respect to basal conditions.
Interpretation and Limitations
The cellular responses to various forms of radiation, including ionizing, UV-radiation or exposure to electromagnetic fields have been found to be manifested as reversible or irreversible from structural to functional changes in different studies. Although this study found no effect of EMF on FRTL-5 cells, in vivo, rats exposed to a 900 MHz EMF have shown decreases in serum thyroid stimulating hormone (TSH) and triiodothronine–thyroxin (T3–T4) hormones levels. Future in vivo studies should be conducted to clarify such associations and in vitro, studies exposing cell lines should be conducted for longer periods of time.
EMF exposure does not interfere with the biochemical properties of FRTL-5 cells in vitro.