The effects of radiofrequency electromagnetic fields exposure on human self-reported symptoms: A systematic review of human experimental studies (WHO SR8)

Overview

The increasing use of radiofrequency electromagnetic fields (RF-EMF) since the 1950s has meant widespread exposure for much of the global population. The World Health Organization (WHO) has set out to review the potential health effects of RF-EMF exposure, focusing on self-reported symptoms in humans and the accuracy with which individuals can perceive RF-EMF exposure.

Objectives

• Systematically review effects of RF-EMF exposure on self-reported non-specific symptoms in humans.
• Assess ability to perceive presence or absence of RF-EMF exposure.

Methods

• Eligibility: Experimental studies on general population and those with idiopathic environmental intolerance attributed to EMF (IEI-EMF), in any language.
• Data Sources: Medline, Web of Science, PsycInfo, Cochrane Library, Epistemonikos, Embase, EMF portal (until April 2022).
• Bias Assessment: Used OHAT Risk of Bias tool tailored to this review.
• Analysis: Random-effects meta-analysis, sensitivity analyses.

Findings

• 41 studies included, mainly crossover trials from Europe, totaling 2,874 participants.
• Meta-analyses of 10 exposure-outcome pairs showed no or small, non-significant effects of RF-EMF exposure on symptoms (including headache, sleep disturbances, composite symptoms), with varying certainty of evidence.
• Standard mean differences for symptoms in both general and IEI-EMF groups mostly crossed zero, i.e., indicating lack of consistent effect.
• No evidence found that volunteers could detect RF-EMF exposure better than chance, including for IEI-EMF groups.

Discussion

Study limitations include that laboratory conditions differ from real life, participant demographics (mostly young, healthy volunteers), and the focus on self-reported acute symptoms rather than long-term or chronic effects. The findings cannot rule out real EMF effects, especially for vulnerable groups or under different conditions, and the possibility of effects masked in certain populations remains.

Conclusion

Current evidence suggests that acute RF-EMF exposures below regulatory limits do not cause immediate self-reported symptoms. Self-reported symptoms may relate more to perceptions or beliefs about EMF exposure (nocebo/attribution effects) rather than actual physiological responses. Still, it is crucial to recognize that other long-term or cumulative risks from EMF exposure are not ruled out by this review and deserve further study.

Implications for Practice

• No evidence was found linking acute RF-EMF exposures (below guidelines) to a wide variety of self-reported symptoms for either the general population or those with IEI-EMF.
• The idea of acute effects is better explained by the nocebo or attribution hypothesis.

Implications for Research

• Future research should include wider participant demographics, standardized methodologies, and may investigate exposures above regulatory limits with precautionary approaches.
• Well-designed studies are needed to clarify long-term and sensitive group risks.