Temperature Changes in Chicken Embryos Exposed to a Continuous-Wave 1.25 GHz Radiofrequency Electromagnetic Field

Abstract

A total of 550 fertile chicken eggs (White Leghorn) were exposed to a radiofrequency (RF) electromagnetic field of 1.25 GHz (continuous wave) at six different power flux densities in the range of 9.0-0.75 mW/cm(2). The eggs were exposed either continuously throughout the whole 21 days of incubation (long-term exposure) or in a short-term exposure (1-2 h/day). The temperatures of the embryonic tissue and the amniotic fluid, respectively, were measured with inserted temperature probes. This study was designed to investigate the relationship between exposure and temperature changes in exposed tissues, without considering biological and medical effects. This knowledge is of general interest for studies of nonthermic teratological or embryo-lethal effects of exposure to electromagnetic fields (EMFs). Throughout the entire 21 days of embryonic development, the mean temperature increases in the eggs during the exposure were found to be up to 0.25 degrees C for a power flux density of 1.25 mW/cm(2) and increased to 2.3 degrees C for 9.0 mW/cm(2). The corresponding maximum whole-body SARs for the embryos over the 21 days of embryonic development were 1.45 and 10.44 W/kg, respectively. At 0.75 mW/cm(2) (0.87 W/kg) the extent of the RF-field induced hyperthermia was within the measurement accuracy (+/-0.1 degrees C) of the temperature probes used in the tests. The field-induced temperature increase was greatest in the first week of incubation and was less pronounced in the last (third) week before hatching. In both the short- and the long-term exposures, the temperature of the exposed tissue and the amniotic fluid, respectively, reached its maximum (asymptotic) approximately 40-50 min after the RF field was switched on. After the field was switched off, the temperature inside the exposed eggs returned to its initial value within 40-50 min.

Effects of extremely low-frequency electromagnetic fields (ELF-EMF) exposure on B6C3F1 mice

“…Although the energy associated with environmental EMFs is too low to cause direct changes to the structure of DNA, EMFs might affect the production of agents such as free radicals, which themselves can react with DNA, or other agents that cause chromosomal damage, instigating translocation by inducing DNA breaks or formation of unnatural DNA structures [22]. Chicken embryos exposed to a continuous-wave 1.25 GHz radiofrequency electromagnetic field shows the increased temperature changes [27]. Moreover, increased expression of heat shock protein (HSP) in magnetic field has been shown [28].…”

Effects of cell phone radiation on the levels of T3, T4 and TSH, and histological changes in thyroid gland in rats treated with Allium sativum extract

“…Thus, the signals transmitted by a cell phone can reach all parts of the body and penetrate into the living tissues, and influence the body at the cellular level (Sarookhani et al, 2011). It is possible to say that the deleterious effects of electromagnetic microwaves are generally exerted through elevation of body temperature (Thalau et al, 2003;Bagher et al, 2009) and creation of free radicals (Rollwitz et al, 2004;Bagher et al, 2009).…”

Study of potential health effects of electromagnetic fields of telephony and Wi‐Fi, using chicken embryo development as animal model

“…On the other hand, Velizarov et al [1999] reported that RF-EMF exposure had a different effect on cultured cells than a temperature change. In a study on chicken embryo development, Saito et al [1991] reported embryo-lethal and/or teratogenic effects and delayed hatching after exposing eggs to a 428 MHz radiofrequency (RF) radiation at a power density of 5.5 mW/cm 2 during incubation, but as later shown by Thalau et al [2003] these may have been thermal effects.…”

“…In most studies, it was assumed that the observed effects were mediated by a non-thermal mechanism. In a study on chicken embryo development, Saito et al [1991] reported embryo-lethal and/or teratogenic effects and delayed hatching after exposing eggs to a 428 MHz radiofrequency (RF) radiation at a power density of 5.5 mW/cm 2 during incubation, but as later shown by Thalau et al [2003] these may have been thermal effects. For instance, in the Caenorhabditis study [de Pomerai et al, 2000], it was later found [de Pomerai et al, 2006] that a local temperature increase of 0.2 8C could occur in the nematode and that heating by 0.2 8C in the nematode was enough to induce the effects seen by EMF radiation.…”