Weak radiofrequency fields affect the insect circadian clock

Abstract

It is known that the circadian clock in Drosophila can be sensitive to static magnetic fields (MFs). Man-made radiofrequency (RF) electromagnetic fields have been shown to have effects on animal orientation responses at remarkably weak intensities in the nanotesla range. Here, we tested if weak broadband RF fields also affect the circadian rhythm of the German cockroach ( Blatella germanica ). We observed that static MFs slow down the cockroach clock rhythm under dim UV light, consistent with results on the Drosophila circadian clock. Remarkably, 300 times weaker RF fields likewise slowed down the cockroach clock in a near-zero static magnetic field. This demonstrates that the internal clock of organisms can be sensitive to weak RF fields, consequently opening the possibility of an influence of man-made RF fields on many clock-dependent events in living systems.

Magnetic fluctuations affect circadian patterns of locomotor activity in zebrafish

“…This is also evidenced by significant correlations between the studied here behavioral endpoints and experimental magnetic fluctuations. Earlier, it was reported that magnetic influence could affect circadian rhythms in different organisms [41,42]. However, until the present study, there were no direct experimental data in support of the entrainment of endogenous circadian oscillators to slow magnetic fluctuations.…”

Radical pairs can explain magnetic field and lithium effects on the circadian clock

“…It is also well-known that the superoxide radical, , can be an alternative partner for the flavin radical 58 – 61 . It has also been proposed that RPs can play important roles in the magnetosensitivity of Drosophila ’s CC 21 , 25 , 62 .…”

Radical pairs can explain magnetic field and lithium effects on the circadian clock

“…In the 1960s, Brown et al [11] found that small changes in the intensity of Earth’s MF synchronize the CCs of fiddler crabs and other organisms. Since then, the effects of external MF on the CC have been observed in multiple studies [12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24]. Similarly, Yoshii et al [25] have shown the effects of static MFs on the CC of Drosophila and found that exposure to these fields exhibited enhanced slowing of clock rhythms in the presence of blue light, with a maximal alteration at 300 µ T, and reduced effects at both lower and slightly higher field strengths.…”

“…It is also well-known that the superoxide radical, O 2 •– , can be an alternative partner for the flavin radical [58, 59, 60, 61]. It has also been proposed that RPs can play important roles in the magnetosensitivity of Drosophila ’s CC [21, 25, 62].…”