Worldwide, the number of insects is decreasing at an alarming rate. It is known that among other causes, the use of pesticides and modern agricultural practices play a particularly important role. The cumulative effects of multiple low-dose toxins and the spread of toxins in nature have not yet been methodically researched, or only in the early stages.
Existing research indicates another factor of anthropogenic origin, which might cause subtle adverse effects: the increasingly frequent use of artificial electromagnetic fields (EMF) such as high voltage, mobile telephony and Wi-Fi. The infrastructure of the next generation of mobile communications technologies, 5G, is being deployed without having been previously tested for possible toxic effects. With mankind’s aspirations for omnipresence of technology, even modest effects of electromagnetic fields on organisms might eventually reach a saturation level that can no longer be ignored.
This systematic review evaluates the state of knowledge regarding the toxic effects of electromagnetic fields (EMF) on insects. Also included is a general review of reported effects and mechanisms of EMF exposure, which addresses new findings in cell biology. 72 of 83 analyzed studies found an effect. Negative effects that were described in studies include: disturbance of the sense of orientation, reduced reproductive ability and fertility, lethargy, changes in flight dynamics, failure to find food, reduced reaction speeds, escape behavior, disturbance of the circadian rhythm, blocking of the respiratory chain and damage to the mitochondria, misactivation of the immune system, increased number of DNA strand breaks.
Some mechanisms of action leading to these damages are identified. EMFs affect the metabolism, among other things affecting voltage-gated calcium channels, e.g. in neurotransmission and in muscle tissue, which can lead to an overactivation of signal transduction and of the respiratory chain with production of free oxygen radicals and consequently leading to oxidative cell stress.
The results show that EMF could have a serious impact on the vitality of insect populations. In some experiments it was found that despite low levels of exposure to transmitters, harmful effects occurred after several months. Field strengths 100 times below the ICNIRP limits could already have effects. Against the background of the rapid decline of insects and the further expansion of high-frequency electromagnetic field sources, there is not only an urgent need for further research, but also in particular on the interactions with other harmful noxious agents, such as pesticides. When planning the expansion of mobile networks, insect habitats should be protected from high-intensity EMF exposure already now.