Diatom motility: the search for independent replication of biological effects of extremely low-frequency electromagnetic fields.
OBJECTIVE
To investigate the hypothesis that exposure to a certain combination of static and time-varying electromagnetic fields (EMF) results in an increase in motility of the marine diatom Amphora coffeaeformis.


METHODS
Diatom motility on agar was positively correlated with calcium ion (Ca2+) concentration. In previous experiments extremely low frequency EMF (16 Hz) had the greatest effect on diatoms at suboptimal for movement Ca2+ concentrations. To ensure that the required suboptimal Ca2+ concentration and resultant cell motility were found, a number of low concentrations of Ca2+ were experimentally tested. The EMF exposure conditions were those at the calculated calcium resonances (B(V)=0 microT; B(H)=20.9 microT; B(AC)=41.8 microT peak-peak 16 Hz) previously found to cause enhanced motility. Diatom movement on agar plates under EMF and control exposures was recorded.


RESULTS
There was no significant difference in cell motility between control and EMF-exposed diatoms at each Ca2+ concentration tested.


CONCLUSIONS
The study indicates that low-frequency EMF set at resonance conditions did not cause an increase in motility of the diatoms.
Clarkson
N
N
The Ecology Centre, University of Sunderland, UK.
Davies
M S
MS
Dixey
R
R
D002118:Calcium / Q000494:pharmacology; D017377:Diatoms / Q000502:physiology* / Q000528:radiation effects*; D004574:Electromagnetic Fields; D009068:Movement / Q000528:radiation effects
D002118:Calcium