Shepherd, S., Lima, M.A.P., Oliveira, E.E. et al. Extremely Low Frequency Electromagnetic Fields impair the Cognitive and Motor Abilities of Honey Bees. Sci Rep 8, 7932 (2018). https://doi.org/10.1038/s41598-018-26185-y
Extremely low frequency electromagnetic field (ELF EMF) pollution from overhead powerlines is known to cause biological effects across many phyla, but these effects are poorly understood. Honey bees are important pollinators across the globe and due to their foraging flights are exposed to relatively high levels of ELF EMF in proximity to powerlines. Here we ask how acute exposure to 50 Hz ELF EMFs at levels ranging from 20–100 µT, found at ground level below powerline conductors, to 1000–7000 µT, found within 1 m of the conductors, affects honey bee olfactory learning, flight, foraging activity and feeding. ELF EMF exposure was found to reduce learning, alter flight dynamics, reduce the success of foraging flights towards food sources, and feeding. The results suggest that 50 Hz ELF EMFs emitted from powerlines may represent a prominent environmental stressor for honey bees, with the potential to impact on their cognitive and motor abilities, which could in turn reduce their ability to pollinate crops.
The impact of these high EMFs on flying insects in general, whose biomass is in significant decline41, and pollinators in particular, has been overlooked throughout the debate about the effects of low level EMFs on human health. It is clear that we now need to understand the effects of EMFs on pollinator species in general, the mechanisms underlying these cognitive and motor effects, and the ecological implications of EMF pollution in the field, including impacts on ecosystem services that bees and other insects provide.
Electromagnetic fields (EMF) around transmission lines and experimental coils. (A) 50 Hz EMF distribution around a 400 kV Larger L6 pylon modelled using Maxwell SV modelling software. (B) Photograph showing the double-wound copper coils used to generate EMF. (Ci) The distribution of 50 Hz EMF around the coils with the voltage set to produce a 1000 μT field at the centre, and (Cii) a 7000 μT field at the centre, measured using an Alphalab magnetometer.