Power density, field intensity, and carrier frequency determinants of RF‐energy‐lnduced calcium‐ion efflux from brain tissue

Abstract

To explain a carrier frequency dependence reported for radiofrequency (RF)-induced calcium-ion efflux from brain tissue, a chick-brain hemisphere bathed in buffer solution is modeled as a sphere within the uniform field of the incident electromagnetic wave. Calculations on a spherical model show that the average electric-field intensity within the sample remains the same at different carrier frequencies if the incident power density (Pi) is adjusted by an amount that compensates for the change in complex permittivity (epsilon *r) and the change of wavelength, as a function of carrier frequency. The resulting formula for transforming Pi is seen to follow the pattern of both positive and negative demonstrations of calcium-ion efflux that have been observed at carrier frequencies of 50, 147, and 450 MHz. Indeed, all results obtained at these three frequencies, when related by Pi's that produce the same average electric-field intensity within the sample, are seen to be in agreement; no prediction is contradicted by an experiment.

Microwaves from Mobile Phones Inhibit 53BP1 Focus Formation in Human Stem Cells More Strongly Than in Differentiated Cells: Possible Mechanistic Link to Cancer Risk

“…Correspondingly, the SAR value of 39 mW/kg used here may be optimal for the effects at 915 MHz but not for those at 905 MHz. Alternatively, but less likely, it is possible that the cells have molecular components that have different electrical properties, thus altering the effective intensity (Joines and Blackman 1980). In either case, future testing of the cell response as a function of exposure intensities at 905 and 915 MHz should help to resolve this issue.…”

RF nonlinear interactions in living cells–I: Nonequilibrium thermodynamic theory

“…For these reasons, this article and its companions [Balzano, 2003] describe some very sensitive experimental methods to detect the presence of RF energies emitted by biological preparations because of inelastic and nonlinear interactions between the incident RF energy and the electrical oscillators in living cells. The suggested experiments could be carried out using the same biological preparations employed by the authors [Bawin et al, 1975;Blackman et al, 1979Blackman et al, , 1980Joines and Blackman, 1980;Lin-Liu and Adey, 1982;Lyle et al, 1983;Dutta et al, 1984;Dutta et al, 1989;Penafiel et al, 1997] who found evidence of nonlinear interactions in experiments with 10-20 min exposures.…”

“…Since the 1970s, some researchers [Bawin et al, 1975;Blackman et al, 1979Blackman et al, , 1980Joines and Blackman, 1980;Lin-Liu and Adey, 1982;Lyle et al, 1983;Dutta et al, 1984Dutta et al, , 1989Penafiel et al, 1997] have advanced the hypothesis of nonlinear responses in vitro and in vivo for tissues exposed to low frequency, amplitude modulated RF signals. The experimental results could not be reconciled with a purely linear field response, but necessitated the presence of base band modulating signals in tissue [Adey, 1980].…”

Internal field strength measurements in chick forebrains at 50, 147, and 450 MHz.

“…For example, as shown in Joines and Blackman [1980], P50/P147 values of 3.89, 5.20, 7.85, and 13.1 would predict contradictory results at 50 and 147 MHz, but values in between, including the 7.28 value in Table 2, cannot be rejected by the data. Likewise, from Joines and Blackman [1980], P147/P450 values of 1.00, 11.0, 15.1, and 16.6 would predict contradictory results, but the value of 5.92 in Table 2 cannot be rejected.…”