Electric and magnetic fields are areas of energy that surround electrical devices. Electric fields are created by differences in voltage; the higher the voltage, the stronger the field. Electric fields are produced by the local build-up of electric charges in the atmosphere. Magnetic fields are formed when electric current flows; the greater the current, the stronger the magnetic field.
Electric fields are at their strongest when they are close to a charge or a charged conductor. Their strength diminishes with distance. In addition, walls, buildings, and trees may serve as barriers to electric fields. When power lines are buried in the ground, their electric fields are barely detectable. Magnetic fields are strongest when they are close to their area of origin, and they weaken with distance. But unlike electric fields, magnetic fields are not blocked by structures.
Though invisible to the human eye, electromagnetic fields, which combine electric and magnetic fields, are everywhere in the environment. In addition to the natural sources of electromagnetic fields, there are sources that have been designed by humans. For example, every power socket emits low frequency electromagnetic fields. Other sources include power lines, electrical wiring, microwave ovens, computers, and cell phones.
Researchers are strongly divided on the issue of whether or not electromagnetic fields pose a significant health risk to humans. To highlight this lack of consensus, this chapter is set up differently than others in the book. The first section discusses studies suggesting that electromagnetic fields are harmful, while the second section highlights studies suggesting that electromagnetic fields are not harmful. Although the jury is still out on this matter, avoiding excess exposure to electromagnetic fields may still be a good habit to follow.
In a study published in 2015 in the Journal of Environmental Health Science & Engineering, researchers from Iran wanted to determine the association between the use of cell phones by pregnant women and the spontaneous abortion of a growing fetus. The cohort consisted of 292 women who had unexplained spontaneous abortions before 14 weeks of gestation and 308 women who were pregnant for 14 weeks. All the women were between the ages of 18 and 35 years. Data were collected on both groups of women, who were recruited from 10 hospitals in Tehran. Information on cell phone use was also obtained. The researchers found an association between the use of cell phones and spontaneous abortions. “Although the mechanisms underlying the effects of EMF [electromagnetic fields] on the risk of spontaneous abortions are not well understood, early embryos are known to be sensitive to environmental exposures.” 2
In a study published in 2015 in the journal Environmental Research, researchers from the Netherlands and New Zealand tested residents before and after the construction of a nearby high-voltage power line. Both residents living close to the power line and those living a little further away participated in the two tests that occurred before the power line and the two tests that took place after construction of the power line. The researchers found that the residents living closer to the power line and who had higher incomes were more likely to agree to participate in the study. At baseline, symptom reports of residents living closer to the power line did not differ significantly from residents living further away. Participants were asked about 16 different nonspecific somatic symptoms such as headaches, dizziness, and low back pain. Health complaints tended to begin during construction of the power line. After the power line was opened, those living closest reported symptoms. “This increase in reported symptoms occurred largely parallel to the increase in the belief that these symptoms are caused by a power line.” 3
In a prospective study published in 2015 in the journal Environment International, researchers from Switzerland wanted to determine if the electromagnetic fields from wireless devices had any effect on the memory of adolescents. The cohort consisted of 439 teens, between the ages of 12 and 17 years, from 24 schools in rural and urban areas in central Switzerland. The baseline study took place between June 2012 and February 2013. Students completed questionnaires and performed a computerized memory test. Parents also completed questionnaires. The study was repeated one year later with 425 of the same students and the same study managers. The researchers gained even more information from a subgroup of 95 teens. For three days, these teens carried an exposimeter, a portable measuring device, and kept diaries on a time-activity diary application installed in smartphones. The researchers determined that the exposure to the electromagnetic fields appeared to have an effect on memory. “A change in memory performance over one year was negatively associated with cumulative duration of wireless phone use and more strongly with RF-EMF [radiofrequency electromagnetic fields] dose.” 4
In a study published in 2012 in the journal Bioelectromagnetics, researchers from Austria wanted to learn more about the association between short-term exposure to mobile phone electromagnetic fields and human cognitive performance. The researchers conducted a meta-analysis of the topic that included 17 studies with 749 subjects. The researchers were unable to locate any credible evidence that mobile phones had any short-term impact on human cognitive performance. The cognitive abilities were neither impaired nor improved by the phones’ electromagnetic fields. The researchers concluded that their findings “suggested that a substantial short-term impact of high frequency electromagnetic fields emitted by mobile phones can essentially be ruled out.” 5
In a study published in 2013 in the Journal of Psychosomatic Research, researchers from the United Kingdom and Germany examined the role that media might play in the development of symptoms related to exposure to electromagnetic fields. The cohort consisted of 147 subjects who were randomly assigned to watch a television report about the adverse health effects of WiFi (n=76) or a control film (n=71), which was the same length but addressed the security of mobile phone transmission. After watching the films, the subjects received a sham exposure to a WiFi signal for 15 minutes. The testing took place between January and June 2012 in London. Eighty-two subjects (54 percent) reported symptoms that they maintained were the result of their exposure to WiFi. In addition, the experimental film increased worries about electromagnetic fields among subjects with higher levels of pre-existing anxiety, a greater tendency for somatosensory amplification, and among those who considered themselves to have a higher sensitivity to electromagnetic fields. “Media reports about the adverse effects of supposedly hazardous substances can increase the likelihood of experiencing symptoms following a sham exposure and developing an apparent sensitivity to it.” And, these effects have the potential to continue for longer periods of time. Had the researchers not debriefed the subjects on what had actually occurred, “it is possible that this belief would have made future symptomatic reactions to electromagnetic stimuli more likely.” 7
1. Z. Wang, L. Wang, S. Zheng et al.. “Effects of Electromagnetic Fields on Serum Lipids in Workers of a Power Plant,” Environmental Science and Pollution Research International 23 (2016): 2495-504.
2. F. S. Mahmoudabadi, S. Ziaei, M. Firoozabadi, and A. Kazemnejad, “Use of Mobile Phone During Pregnancy and the Risk of Spontaneous Abortion,” Journal of Environmental Health Science & Engineering 13 (2015): 34+.
3. Jarry T. Porsius, Liesbeth Claassen, Tjabe Smid et al., “Symptom Reporting After the Introduction of a New High-Voltage Power Line: A Prospective Field Study,” Environmental Research 138 (2014): 112-17.
4. Anna Schoeni, Katharina Roser, and Martin Röösli, “Memory Performance, Wireless Communication and Exposure to Radiofrequency Electromagnetic Fields: A Prospective Cohort Study in Adolescents,” Environment International 85 (2015): 343-51.
5. Alfred Barth, Ivo Ponocny, Timo Gnambs, and Robert Winkler, “No Effects of Short-Term Exposure to Mobile Phone Electromagnetic Fields on Human Cognitive Performance: A Meta-Analysis,” Bioelectromagnetics 33, no. 2 (2012): 159-65.
6. Maël Dieudonné, “Does Electromagnetic Hypersensitivity Originate from Nocebo Responses? Indications from a Qualitative Study,” Bioelectromagnetics 37, no. 1 (2016): 14-24.
7. Michael Witthöft and G. James Rubin, “Are Media Warnings About the Adverse Health Effects of Modern Life Self-Fulfilling? An Experimental Study on Idiopathic Environmental Intolerance Attributed to Electromagnetic Fields (IEI-EMF),” Journal of Psychosomatic Research 74 (2013): 206-12.
Barth, Alfred, Ivo Ponocny, Timo Gnambs, and Robert Winkler. “No Effects of Short-Term Exposure to Mobile Phone Electromagnetic Fields on Human Cognitive Performance: A Meta-Analysis.” Bioelectromagnetics 33, no. 2 (2012): 159-65.
Dieudonné, Maël. “Does Electromagnetic Hypersensitivity Originate from Nocebo Responses? Indications From a Qualitative Study.” Bioelectromagnetics 37, no. 1 (2016): 14-24.
Goedhart, Geertje, Martine Vrijheid, Joe Wiart et al. “Using Software-Modified Smartphones to Validate Self-Reported Mobile Phone Use in Young People: A Pilot Study.” Bioelectromagnetics 36 (2015): 538-43.
Kato, I., A. Young, J. Liu et al. “Electric Blanket Use and Risk of Thyroid Cancer in the Women’s Health Initiative Observational Cohort.” Women & Health 55, no. 7 (2015): 829-41.
Mahmoudabadi, F. S., S. Ziaei, M. Firoozabadi, and A. Kazemnejad. “Use of Mobile Phone During Pregnancy and the Risk of Spontaneous Abortion.” Journal of Environmental Health Science & Engineering 13 (2015): 34+
Porsius, Jarry T., Liesbeth Claassen, Tjabe Smid et al. “Symptom Reporting After the Introduction of a New High-Voltage Power Line: A Prospective Field Study.” Environmental Research 138 (2015): 112-17.
Qi, G., X. Zuo, L. Zhou et al. “Effects of Extremely Low-Frequency Electromagnetic Fields (ELF-EMF) Exposure on B6C3F1 Mice.” Environmental Health and Preventive Medicine 20, no. 4 (2015): 287-93.
Schoeni, Anna, Katharina Roser, and Martin Röösli. “Memory Performance, Wireless Communication and Exposure to Radiofrequency Electromagnetic Fields: A Prospective Cohort Study in Adolescents.” Environment International 85 (2015): 343-51.
Wang, Z., L. Wang, S. Zheng et al. “Effects of Electromagnetic Fields on Serum Lipids in Workers of a Power Plant.” Environmental Science and Pollution Research International 23 (2016): 2495-504.
MedlinePlus. www.nim.nih.gov/medlineplus .
World Health Organization. www.who.int/ .