Nov 2, 2021

Radio-Frequency Exposure of the Yellow Fever Mosquito (A. aegypti) from 2 to 240 GHz

Eline De Borre, Wout Joseph, Reza Aminzadeh, Pie Müller, Matthieu Boone, Iván Josipovic, Sina Hashemizadeh, Niels Kuster, Sven Kühn, and Arno Thielens, PLOS Computational Biology 2021, Volume 17, Issue 10, Article Number e1009460, online 28 October 2021; doi: 10.1371/journal.pcbi.1009460

Fifth generation networks (5G) will be associated with a partial shift to higher carrier frequencies, including wavelength sizes of insects, which could lead to higher absorption of radiofrequency (RF) electromagnetic fields (EMF) and cause dielectric heating in insects. The yellow fever mosquito Aedes aegypti, which is a vector for diseases such as yellow and dengue fevers, favors warm climates. Exposure to higher-frequency RF EMFs that possibly cause dielectric heating could have an influence on behavior, physiology, and morphology, and could possibly lead to introduction of the species in regions where the yellow fever mosquito does not normally appear. In this study, the influence of far-field RF exposure on A. aegypti was examined between 2 and 240 GHz. Finite difference time domain (FDTD) simulations were used to determine the distribution of the EMF in and around the insect, and the absorbed RF power levels for six different mosquito models (three male, three female) were found. The 3D models were created from micro-CT scans of real mosquitoes. The dielectric properties used in the simulation were measured from a mixture of homogenized A. aegypti. For a given incident RF power, the absorption was found to increase with increasing frequency between 2 and 90 GHz, with a maximum between 90 and 240 GHz. The absorption was maximal in the region where the wavelength matches the size of the mosquito. For an equivalent incident field strength, the power absorption by the mosquito is 16 times greater at 60 GHz than at 6 GHz. The higher absorption of RF power by future technologies can result in dielectric heating and potentially influence the biology of this mosquito species.

The scientific and technical impact of the study can be summarized as:

  • Six high-resolution 3D models of mosquitos – the first models to be based on real mosquitoes at high spatial resolution – were created
  • The dielectric properties of homogenized yellow fever mosquitoes over the frequency range of 5 – 67 GHz were measured for the first time with the coaxial-probe technique
  • The RF exposure of these mosquitoes at frequencies between 2 and 240 GHz was numerically simulated, leading to first-ever insights into how RF power is absorbed at frequencies in the 4G and the future 5G mm-wave environments
  • The distribution of EMFs in and around the mosquito showed higher field strengths in the insect for 120 and 240 GHz than at 6 GHz, indicating that carrier frequencies of telecommunication systems >6 GHz will result in higher absorption of EMF by yellow fever mosquitoes, which can cause dielectric heating and have an impact on behavior, development, and possibly the expansion of the insect into new bioenvironments