The bioeffects of extremely weak power-frequency alternating magnetic fields

Abstract

We report the results of a study of the influence of extremely-weak alternating magnetic fields (EW AMF) directed co-linearly to the static Earth's magnetic field on the rate of regeneration in planarians and also on the rate of gravitropic response in the stem segments of flax. In particular we obtained the data on the dependence of the value of bioeffects on the amplitude (at fixed 60 Hz-frequency) and on the frequency (at fixed 1.6 lT-amplitude) of the alternating component. Our data show unambiguously that EW AMF substantially affect the properties of the biosystems. The experimental data may be approximated by the theoretical expression following directly from a general formula, derived in the theory of magnetic parametric resonance. Our data indicate that the nuclear spins of hydrogen atoms serve as the primary targets for the action of the EW AMF on the biosystems. The values of bioeffects of combined magnetic fields with extremely weak alternating component are completely determined by the parameter cB AC =f , where c = 42.578 Hz/lT-gyromagnetic ratio of the nuclear spins of hydrogen atoms, and B AC and f correspond to magnetic induction and frequency of the alternating magnetic component. The dependence of bioeffect's value on cB AC =f -parameter is polyextremal: well expressed maxima are observed at cB AC =f ¼ 0:9; 2:75 and minor maxima at cB AC =f ¼ 4:5; 6:1. The bioeffects are absent at cB AC =f ¼ 1:8, 3.8, 5.3, 6.7. At the values of B AC [8--10 lT the bioeffect changes its sign-activation of planarian's regeneration starts to be replaced by its inhibition. The inhibition takes place for the range of the amplitudes from 10 to 140 lT. The observed change in the sign of the effect may result to the prevalence of the effects caused by the induction of the alternating currents in the test-system at relatively high B AC -amplitudes. These results provide the basis for planning of the epidemiological studies and interpretation of the corresponding results.

Reduced growth of soybean seedlings after exposure to weak microwave radiation from GSM 900 mobile phone and base station

“…Only a few studies of EMF effects on plants [Tkalec et al, 2005[Tkalec et al, ,2007[Tkalec et al, ,2009Sharma et al, 2009] have been reported. In early studies seeds were exposed to extremely low frequency (ELF) magnetic fields or RF radiation in order to investigate biological effects [Bigu-Del-Blanco et al, 1977;Belova and Lednev, 2001;Belova et al, 2007;Tkalec et al, 2009;Shine et al, 2011], however, the results are inconsistent.…”

Effect of weak combined static and extremely low‐frequency alternating magnetic fields on tumor growth in mice inoculated with the Ehrlich ascites carcinoma

“…Most experiments devoted to the effect of weak combined alternating (AC) and static (DC) magnetic fields (MFs) on biosystems have been performed using fields with the amplitude of the AC component of tens of microteslas against the background of the static MF of comparable strength. However, there is substantial evidence indicating that very weak alternating MFs of the nanotesla range are also capable of inducing marked biological effects [Juutilainen et al, 1987;Berman et al, 1990;Liburdy et al, 1993;Novikov et al, 1996Novikov et al, , 2005Novikov et al, , 2008Persinger et al, 1999;Belova and Lednev, 2001;Blackman et al, 2001;Novikov, 2004;Bobkova et al, 2005;Belova et al, 2007]. It should be noted that in the majority of cases, the experiments with very weak AC MFs were conducted against the background of the geomagnetic field whose magnetic flux density is $50 mT.…”

Impact of physical factors on the society and environment

“…Belova et al (2007) paid a special attention on the biological effects of alternating magnetic fields originated from natural and technogenic sources. The spectrum of the effects of lowintensity magnetic field could be extended with the paper of Abdolmaleki et al (2007) who discussed the role of static magnetic fields on cell death.…”