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(Database last updated on Mar 27, 2024)
| ID Number | 467 | |
| Study Type | In Vitro | |
| Model | 147, 450 MHz (CW, AM-16 Hz) exposure to chick brain tissue and analysis of Ca++ efflux. | |
| Details | Chick brain tissue (from 2-5 day old chicks) was exposed to 147-MHz (CW and PW- AM at 0.5, 3, 6, 9, 11, 16, 20, 25, or 35 Hz) for 20 minutes at 1-2 mW/cm2 using the exposure system described by Bawin et al. (Brain Res 1973, 58:365-384). Exposure to 147-MHz CW or AM at 0.5 and 3 Hz did not affect 45-Ca++ efflux. Exposure to 147 MHz AM at 6, 9, 11, and 16 Hz did, however, caused a significant increase in 45-Ca++ efflux, with AM at 20, 25, and 35 Hz causing progressively less of an effect. Importantly, this effect was also observed in tissue poisoned by Na-cyanide indicating that it was not due to channel activation / deactivation or any other active metabolic process. The effect of 147 MHz RF (AM at 6-16 Hz) was not observed in skeletal muscle preparations. The authors concluded that certain modulation frequencies of a 147 MHz carrier are able to increase Ca++ efflux from isolated neonatal chick brains. A similar study using 450 MHz was performed in Proc Natl Acad Sci U S A (1976) 73:1999-2003. More detailed analysis was also performed, and again chick brain tissue exposed to 147 & 450 MHz (AM-16 Hz) for 20 minutes at 0.1 to 5 mW/cm2 resulted in an increased efflux of 45Ca++. This efflux was inhibited by a lack of buffering agents, increased with low pH, and suggested by the authors to be due to interaction with extracellular and ion sensitive Ca++ binding sites. In addition, the increased Ca++ efflux was observed at 0.1 and 1 mW/cm2, but not at 2-5 mW/cm2 suggesting power density windows for the effects. In related studies, preloaded rat synaptosomes were loaded with 45Ca++ and exposured to 450 MHz (AM-16 Hz) at 0.5 mW/cm2. Exposure using the AM-16 Hz signal resulted in increased 45Ca++ efflux while 450 MHz CW and AM-60 Hz did not. The authors also reported that the MW induced Ca++ efflux was different than that stimulated by CaCl, which is derived intracellularly, and suggest whole cells or organized tissue are not required for the MW effect. In other studies, live cats were exposed to 450 MHz (AM-16Hz) for 60 minutes at ~0.3 W/kg (to the interhemispheric fissure) using a horn irradiator. Exposure resulted in irregular amplitude & duration of brain waves and an increased efflux of 45Ca++. In addition, in the majority of cases exposure also resulted in a transient increase in end-tidal CO2. AUTHOR'S ABSTRACT: Adey 1993 (IEEE #6519): Life on earth has evolved in a sea of natural electromagnetic (EM) fields. Over the past century, this natural environment has sharply changed with introduction of a vast and growing spectrum of man-made EM fields. From models based on equilibrium thermodynamics and thermal effects, these fields were initially considered too weak to interact with biomolecular systems, and thus incapable of influencing physiological functions. Laboratory studies have tested a spectrum of EM fields for bioeffects at cell and molecular levels, focusing on exposures at athermal levels. A clear emergent conclusion is that many observed interactions are not based on tissue heating. Modulation of cell surface chemical events by weak EM fields indicates a major amplification of initial weak triggers associated with binding of hormones, antibodies, and neurotransmitters to their specific binding sites. Calcium ions play a key role in this amplification. These studies support new concepts of communication between cells across the barriers of cell membranes; and point with increasing certainty to an essential physical organization in living matter, at a far finer level than the structural and functional image defined in the chemistry of molecules. New collaborations between physical and biological scientists define common goals, seeking solutions to the physical nature of matter through a strong focus on biological matter. The evidence indicates mediation by highly nonlinear, nonequilibrium processes at critical steps in signal coupling across cell membranes. There is increasing evidence that these events relate to quantum states and resonant responses in biomolecular systems, and not to equilibrium thermodynamics associated with thermal energy exchanges and tissue heating. |
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| Findings | Effects | |
| Status | Completed With Publication | |
| Principal Investigator | Univ. California Riverside | |
| Funding Agency | DOE, USA | |
| Country | UNITED STATES | |
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