Review 1 Mention
The effects of radiofrequency electromagnetic fields exposure on human self-reported symptoms: A systematic review of human experimental studies
Xavier Bosch‐Capblanch•2024
Ekpereonne EsuChioma Moses Oringanje
Top 12% · 88th Percentile
37 citations · Biophysics
Open Access

TLDR

Brief exposure to wireless signals below official safety limits did not cause reported symptoms. People who felt sensitive could not reliably tell whether the signals were present.

Summary

1 Study Aim

The authors aimed to assess whether radiofrequency electromagnetic fields (RF-EMF; invisible energy used by wireless technologies) cause self-reported, non-specific symptoms (varied symptoms without one specific diagnosis). They also examined whether people, including those with idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF; reported sensitivity to such fields), could correctly identify exposure. The study asked whether brief wireless-signal exposure causes symptoms or can be consciously detected.

2 Study Design

The authors conducted a systematic review (structured search and synthesis of existing studies). They searched seven databases through April 2022. Eligible studies experimentally exposed general-population participants and people with IEI-EMF. Forty-one studies included 2,874 participants, mostly in Europe. Most were crossover trials, where participants experienced different exposure conditions. The authors combined suitable results using random-effects meta-analysis (a method allowing study results to differ). They assessed ten exposure-symptom comparisons. The researchers combined results from 41 controlled human studies involving nearly 2,900 people.

3 Findings

Across ten exposure-symptom comparisons, evidence showed no or small, non-significant effects, with certainty ranging from high to very low. In the general population, headache, sleep disturbance, and combined symptoms stayed close to zero. For people reporting IEI-EMF, effects were also small, and all uncertainty ranges included no effect. Participants could not identify exposure better than chance. People reporting IEI-EMF did not identify exposure more accurately than other participants. The authors caution that most studies involved young, healthy volunteers and brief exposures unlike daily life. The evidence did not assess long-term exposure, older adults, or chronically ill people. They conclude that acute exposure below official limits does not cause symptoms. Brief exposure below official limits did not make people feel symptoms, and people could not tell when signals were present.

Abstract

BACKGROUND: The technological applications of radiofrequency electromagnetic fields (RF-EMF) have been steadily increasing since the 1950s exposing large proportions of the population. The World Health Organization (WHO) is assessing the potential health effects of exposure to RF-EMF. OBJECTIVES: To systematically assess the effects of exposure to RF-EMF on self-reported non-specific symptoms in human subjects and to assess the accuracy of perceptions of presence or absence of RF-EMF exposure. METHODS: Eligibility criteria: experimental studies carried out in the general population and in individuals with idiopathic environmental intolerance attributed to EMF (IEI-EMF), in any language. INFORMATION SOURCES: Medline, Web of Science, PsycInfo, Cochrane Library, Epistemonikos, Embase and EMF portal, searched till April 2022. Risk of Bias (ROB): we used the RoB tool developed by OHAT adapted to the topic of this review. SYNTHESIS OF RESULTS: we synthesized studies using random effects meta-analysis and sensitivity analyses, where appropriate. RESULTS: Included studies: 41 studies were included, mostly cross over trials and from Europe, with a total of 2,874 participants. SYNTHESIS OF RESULTS: considering the primary outcomes, we carried out meta-analyses of 10 exposure-outcomes pairs. All evidence suggested no or small non-significant effects of exposure on symptoms with high (three comparisons), moderate (four comparisons), low (one comparison) and very low (two comparisons) certainty of evidence. The effects (standard mean difference, where positive values indicate presence of symptom being exposed) in the general population for head exposure were (95% confidence intervals) 0.08 (-0.07 to 0.22) for headache, -0.01 (-0.22 to 0.20) for sleeping disturbances and 0.13 (-0.51 to 0.76) for composite symptoms; and for whole-body exposure: 0.09 (-0.35 to 0.54), 0.00 (-0.15 to 0.15) for sleeping disturbances and -0.05 (-0.17 to 0.07) for composite symptoms. For IEI-EMF individuals SMD ranged from -0.19 to 0.11, all of them with confidence intervals crossing the value of zero. Further, the available evidence suggested that study volunteers could not perceive the EMF exposure status better than what is expected by chance and that IEI-EMF individuals could not determine EMF conditions better than the general population. DISCUSSION: Limitations of evidence: experimental conditions are substantially different from real-life situations in the duration, frequency, distance and position of the exposure. Most studies were conducted in young, healthy volunteers, who might be more resilient to RF-EMF than the general population. The outcomes of interest in this systematic review were symptoms, which are self-reported. The available information did not allow to assess the potential effects of exposures beyond acute exposure and in elderly or in chronically ill people. It cannot be ruled out that a real EMF effect in IEI-EMF groups is masked by a mix with insensitive subjects. However, studies on symptoms reporting and/or field perceptions did not find any evidence that there were particularly vulnerable individuals in the IEI-EMF group, although in open provocation studies, when volunteers were informed about the presence or absence of EMF exposure, such differences were consistently observed. INTERPRETATION: available evidence suggests that acute RF-EMF below regulatory limits does not cause symptoms and corresponding claims in the everyday life are related to perceived and not to real EMF exposure status.

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