Reviews

In connection with the planned expansion of high-voltage direct current transmission lines, RWTH Aachen University has published two reviews on the effects of static electric fields on living organisms and plants^{[1, 2]}.

Eight human studies and 40 mammalian studies were analysed ^[1]. Because electric fields do not penetrate the body, acute health-relevant effects are not to be expected and have not been found. In general, it was shown that humans and animals can perceive strong electric fields above certain threshold values by means of their pelage and then react accordingly physiologically or in their behaviour. Some studies on physiological responses were of insufficient quality. The perception thresholds of humans are always lower (about 20 kV/m) for whole body exposure than for partial body exposure. More research is needed on perception thresholds.

In the second part of the study ^[2], 14 publications on invertebrates and 19 studies on plants that met the quality criteria were analysed. No negative physiological or health-relevant influences on lower animals and plants were described at field strengths that can be expected under power lines (< 35 kV/m). Invertebrates reacted behaviourally to static electric fields. Negative effects occurred at much higher field strengths. Studies with improved quality are necessary to distinguish effects of fields, corona ions, ionic currents, ozone, and nitrogen oxide.

Another review paper ^[3] describes the ecological aspects of electricity. Naturally occurring electric fields and charges as well as the corresponding reactions and perceptions of animals are described. The authors discuss the role of electric fields in the orientation, communication, prey search, pollination, and dispersal of some animal species. The functioning of sensory organs that serve to perceive electric fields in sharks and rays, electric fish, insects, and other invertebrates is explained. Possible effects of anthropogenic electric fields are only briefly addressed and mainly in connection with marine animals and insects. However, it goes without saying that wherever animals perceive natural electric fields and use them for orientation and communication, anthropogenic fields can lead to disturbances of these behaviours.

References

[1] Petri AK, Schmiedchen K, Stunder D, Dechent D, Kraus T, Bailey WH, Driessen S (2017). Biological effects of exposure to static electric fields in humans and vertebrates: a systematic review. Environ Health 16(1): 41.

[2] Schmiedchen K, Petri AK, Driessen S, Bailey WH (2018). Systematic review of biological effects of exposure to static electric fields. Part II: Invertebrates and plants. Environ Res 160: 60-76.

[3] England SJ, Robert D (2022) The ecology of electricity and electroreception. Biol Rev 97(1): 383-413.