BERENIS – The Swiss expert group on electromagnetic fields and non-ionising radiation

donderdag, 04 februari 2021 - Categorie: Onderzoeken

BERENIS – The Swiss expert group on electromagnetic fields and non-ionising radiation
Newsletter – Special Issue January 2021


www.bafu.admin.ch/dam/bafu/en/dokumente/elektrosmog/fachinfo-daten/newsletter_berenis_sonderausgabe_januar_2021.pdf

This special issue of the BERENIS newsletter contains an up-to-date assessment of a possible
correlation between oxidative stress and exposure to magnetic and electromagnetic fields and their
putative effects on health. For this purpose, relevant animal and cell studies published between 2010
and 2020 were identified and summarized. An extended report presenting these recent studies in more
detail will be published soon by the FOEN1
. This special issue contains a short version of the report.

Is there evidence for oxidative stress caused by electromagnetic fields?
A summary of relevant observations in experimental animal and cell experiments related to
health effects in the last ten years
Prof Meike Mevissen, University of Bern
Dr David Schürmann, University of Basel

Introduction and aims of this report
Reactive oxygen species (ROS) are involved in many processes of the organism, including cellular
signalling pathways; therefore, physiological concentrations of ROS in cells need to be maintained by
engaging protective mechanisms (antioxidative enzymes and antioxidants). On the other hand,
external and internal factors influence the amount of ROS by altering the activity of the ROS-forming
and -degrading enzymes. For instance, the increased energy requirement during physical activity leads
to a temporary oxidative stress and many environmental stress factors such as UV light or radioactive
irradiation act via ROS formation. An oxidative imbalance has an effect on many important
physiological processes and functions, such as inflammation, cell proliferation and differentiation,
wound healing, neuronal activity, reproduction and behaviour by altering biochemical processes or
even leading to DNA damage or peroxidation of fats. In particular, changes in cell proliferation and
differentiation are closely related to carcinogenesis and the growth and development of organisms.
Concerning putative adverse health impact, the influence of electromagnetic fields (EMF), as an
environmental factor, on the formation of ROS and triggers of oxidative stress was considered.
Respective hypotheses and experimental findings were summarised and discussed in scientific reviews
as well as in reports of public organisations 1-12. Despite some evidence of ROS formation and
oxidative stress by EMF, a scientific consensus is not yet achieved, especially when it comes to possible
negative and long-term effects on our health.
Aiming at an up-to-date assessment of a possible correlation between oxidative stress and exposure
to magnetic and electromagnetic fields and their putative effects on health, this topic is revisited here
by identifying and summarizing recent and relevant animal and cell studies. This primarily involves
experimental data of animals and cultured cells from peer-reviewed publications (about 150 studies in
total) in the period 2010-2020. An extended report presenting these recent studies in more detail will be published soon on the FOEN website. Herein, the focus was set on publications dealing with EMF in
the frequency ranges relevant to the environment and technology: extremely-low-frequency magnetic
fields (ELF-MF), typical for 50/60 Hz alternating current power lines, as well as radio-frequency
electromagnetic fields (RF-EMF) from 800 MHz to 2.5 GHz as used for mobile communication systems.
The experimental studies investigated the influence of EMF exposure on the formation of ROS, markers
of oxidative stress, and changes in the protective mechanisms that counteract oxidative stress. These
publications may be of a purely descriptive nature, while others may contain mechanistic aspects that
specifically track and investigate interrelationships and influenced processes. It should be noted that
not only primary but also established and cancerous cells have been used to study the formation and
occurrence of ROS and related changes in cellular signalling pathways and protective mechanisms. In
animal studies, the balance of ROS and the antioxidative mechanisms can be studied in the whole
organism. In contrast to cell culture studies, functional changes caused by a permanent oxidative
imbalance can be investigated in animals, providing more relevant data for the evaluation of health
impacts. Therefore, animals studies in which functional changes are considered and assessed are
particularly important for the assessment of the impact of EMF on human health.

For the next sections see the link on top. Below the conclusions
Conclusions

In summary, the majority of the animal and more than half of the cell studies provided evidence of
increased oxidative stress caused by RF-EMF or ELF-MF. This notion is based on observations in a large
number of cell types, applying different exposure times and dosages (SAR or field strengths), also in the range of the regulatory limits. Certainly, some studies are burdened with methodological
uncertainties and weaknesses or are not very comprehensive in terms of exposure time, dose, number
and quantitative analysis of the biomarkers used, to name a few. Taking these methodological
weaknesses into account, nonetheless, a tendency becomes apparent, namely that EMF exposure,
even in the low dose range, can lead to changes in oxidative balance. Organisms and cells are generally
able to react to oxidative stress, and many studies showed adaptation to EMF exposure after a
recovery phase. Pre-existing conditions, such as immune deficiencies or diseases (diabetes,
neurodegenerative diseases), compromise the body's defence mechanisms, including antioxidative
protection, and it is therefore possible that individuals with these conditions experience more severe
health effects. In addition, the studies show that very young and elderly individuals can react less
efficiently to oxidative stress induced by EMF, which of course also applies to other stressors that cause
oxidative stress. More extensive studies under standardised conditions are necessary, to better
understand and confirm these phenomena and observations.



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