Brain & Nervous SystemNo Effects Found
Neurodevelopment for the first three years following prenatal mobile phone use, radio frequency radiation and lead exposure.
Choi KH et al. · 2017
At a Glance
Of the 874 peer-reviewed studies in this collection on electromagnetic fields, 701 — 80.2% — reported biological effects. On children's brains specifically the direct evidence is thin and the honest summary is layered: tissue measurements show absorption properties change with age, animal work shows radiofrequency exposure producing DNA strand breaks in brain cells, one large birth cohort links prenatal phone exposure to behavioral difficulties while cautioning the link may be non-causal, and the largest brain-tumor study found no overall increase in risk.
Based on analysis of 903 peer-reviewed studies
Children's brains are fundamentally different from adult brains—not just smaller, but actively developing, forming new neural connections, and undergoing critical periods of growth. This raises important questions about how electromagnetic field exposure might affect the developing brain.
Researchers have approached this question through multiple methods: measuring how much RF energy children's brains absorb compared to adults, studying cognitive outcomes in children with various EMF exposures, and examining brain tissue effects in laboratory settings.
This page presents the scientific evidence on EMF exposure and childhood brain development.
Key Findings
- -701 of 874 studies (80.2%) in this collection found biological effects from electromagnetic field exposure
- -Radiofrequency exposure produced single- and double-strand DNA breaks in rat brain cells at a whole-body absorption rate of 1.2 W/kg, from both pulsed and continuous-wave radiation (Lai and Singh 1996)
- -Tissue dielectric properties decrease with age, most markedly in brain and skull, which is the measured basis for expecting different absorption in children (Peyman 2001)
- -Prenatal phone exposure was associated with emotional and hyperactivity problems at age seven across 13,159 children, an association the authors warn may be non-causal (Divan 2008)
- -The largest brain-tumor study found no overall increased risk — 2,708 glioma and 2,409 meningioma cases across 13 countries — with suggestions of elevated glioma risk at the highest exposures that bias prevents interpreting causally (INTERPHONE 2010)
What the Research Shows
What the Research Shows
Of the 874 peer-reviewed studies indexed here on electromagnetic fields, 701 — 80.2% — reported measurable biological effects. Very few examine children's brains directly. Children cannot be enrolled in controlled radiofrequency exposure experiments, so the evidence comes from animal brain tissue, tissue-property measurement, adult cognitive testing, and observational cohorts.
How Absorption Changes With Age
Peyman and colleagues (2001) measured the dielectric properties of ten rat tissues at six ages across 130 MHz to 10 GHz. Properties decreased with age, and the trend was most apparent in brain, skull and skin, driven by declining water content. Because those properties govern how radiofrequency energy enters and deposits in tissue, younger tissue interacts with these fields differently. This is the measured basis for treating children's exposure as a distinct question — tissue data from animals, not a measured dose to a child's brain.
What Exposure Does to Brain Cells
Lai and Singh (1996) exposed rats at a spatial-averaged power density of 2 mW/cm², producing a whole-body specific absorption rate of 1.2 W/kg, and measured DNA strand breaks in individual brain cells four hours after exposure. Both single- and double-strand breaks increased, with no significant difference between pulsed and continuous-wave radiation. The authors positioned it as support for earlier in vitro and in vivo work showing radiofrequency effects on DNA.
A developing brain is building the structure it will use for life, and DNA damage during that period carries different consequences than the same damage in a mature, slowly dividing tissue. That reasoning is why the animal result gets weighted heavily in discussions of children — it is an inference about vulnerability, not a measured pediatric outcome.
Cognition and Behavior
Preece and colleagues (1999) tested 36 adults under about 1 W mean power at 915 MHz in a randomized cross-over design. Only choice reaction time changed, and it improved. Word, number and picture recall and spatial memory were unaffected.
The behavioral signal in children comes from Divan and colleagues (2008), who followed 13,159 children in the Danish National Birth Cohort to age seven. Children with possible prenatal or postnatal phone exposure showed greater odds of behavioral problems — emotional and hyperactivity difficulties — with the prenatal association stronger and surviving adjustment for confounders. The authors state that the associations may be non-causal and may reflect unmeasured confounding.
Hutter and colleagues (2006) added population evidence in adults, finding effects on wellbeing and cognitive performance among 365 residents near base stations at exposures far below recommended limits, with no known mechanism at those levels.
The Strongest Counter-Evidence
The INTERPHONE study ran an interview-based case-control study across 13 countries with 2,708 glioma and 2,409 meningioma cases and matched controls. It found no overall increase in either tumor type among mobile phone users — in fact reduced odds ratios that its authors attributed to participation bias or other methodological limitations. Suggestions of increased glioma risk appeared at the highest exposure levels, but the authors concluded that bias and error prevent a causal interpretation. That study concerns adults and tumors, not children and development, and it is the most substantial null result in this area.
What This Does Not Establish
Nothing here demonstrates that phone or WiFi exposure impairs a child's brain development. The tissue and DNA work is animal-based at exposures above typical use. The cognitive findings are in adults and are not uniformly negative. The behavioral cohort measures recalled phone use and carries the confounding its authors name.
Reasonable Practice
The steps that follow from this evidence are the ones that would be sensible even if every study above were overturned: keep phones away from children's heads by using speaker mode or wired headphones, favor texting over calling, keep devices out of bedrooms overnight, and use wired connections where devices do not move. Each reduces exposure during the years when the tissue differences are largest, and none costs anything worth counting.
Related Studies (903)
Brain & Nervous System
Review
Acute effects of radiofrequency electromagnetic field emitted by mobile phone on brain function.
Zhang J, Sumich A, Wang GY. · 2017
The review focuses on recent neuroimaging and electroencephalography studies to analyze effects of MP EMF exposure on neurocognitive function. Several studies indicate an increase in cortical excitability and/or efficiency with EMF exposure, more prominent in fronto-temporal regions and associated with faster reaction time. Cortical excitability might also underpin disruption to sleep. However, several inconsistent findings exist and conclusions regarding adverse effects of EMF exposure are currently limited.
Analysis of ear side of mobile phone use in the general population of Japan.
Sato Y, Kojimahara N, Taki M, Yamaguchi N · 2017
The study aimed to clarify the distribution of ear side of mobile phone use in Japan and factors associated with it. Statistically significant differences were observed only in talk time per call with an odds ratio of 2.17 and a 95% confidence interval of 1.22 to 3.99. In right-handed adults, left-ear use was significantly associated with age groups 30-39 (OR = 2.55; 95% CI: 1.79-3.68), 40-49 (OR = 3.08; 95% CI: 2.15-4.43), over 50 (OR = 1.85; 95% CI: 1.20-2.85), and with work-related talk time of 51-100% (OR = 1.75; 95% CI: 1.21-2.55). The survey included 2,518 children and 1,529 adults who completed an Internet-based survey, and data were analyzed by logistic regression. In children, the analysis focused on right-ear use in right-handed individuals due to dominant-hand tendency.
Mobile phone types and SAR characteristics of the human brain.
Lee AK, Hong SE, Kwon JH, Choi HD, Cardis E. · 2017
Researchers calculated specific absorption rate for four anatomical head models at different ages using 11 numerical phone models of different shapes and antenna configurations. The 11 models represented phone types accounting for around 86% of the approximately 1400 commercial phone models released into the Korean market since 2002. Seven of the phone models selected had an internal dual-band antenna and the remaining four had an external antenna. The 1 g peak spatial SAR and ipsilateral and contralateral brain-averaged SARs were reported for all 11 phone models, and the effects of phone type, phone position, operating frequency, and age of head models on brain SAR were comprehensively determined.
RAPD Profiling, DNA Fragmentation, and Histomorphometric Examination in Brains of Wistar Rats Exposed to Indoor 2.5 Ghz Wi-Fi Devices Radiation.
Ibitayo AO et al. · 2017
Researchers divided young male rats into four groups, with three groups exposed to 2.5 Ghz radiation for 30, 45, or 60 consecutive days. DNA damage was detected using agarose gel electrophoresis, and histomorphometry showed perivascular congestion and tissue damage.
Mobile phones, cordless phones and rates of brain tumors in different age groups in the Swedish National Inpatient Register and the Swedish Cancer Register during 1998-2015.
Hardell L, Carlberg M. · 2017
Researchers analyzed brain tumor rates in the Swedish National Inpatient Register and Swedish Cancer Register from 1998 to 2015. The average annual percentage change for brain tumors increased by 2.06% per 100,000 in both genders combined. A joinpoint in 2007 showed a shift from a 0.16% annual change before 2007 to a 4.24% annual change after 2007. The highest increase was in the 20-39 year age group. The authors concluded that underreporting to the Cancer Register means real incidence is higher and trends should be used with caution.
Maternal cell phone use during pregnancy and child behavioral problems in five birth cohorts.
Birks L et al. · 2017
Researchers analyzed data from 83,884 mother-child pairs across five birth cohorts in Denmark, Korea, the Netherlands, Norway, and Spain. They categorized maternal cell phone use during pregnancy into none, low, medium, and high based on call frequency reported by mothers. Child behavioral problems were assessed using the Strengths and Difficulties Questionnaire or Child Behavior Checklist at ages 5–7 years. A trend of increasing risk of hyperactivity/inattention problems was observed across cell phone use categories, with odds ratios of 1.11 for medium users and 1.28 for high users. The association was consistent across cohorts and between prospective and retrospective data collection methods.
Use of mobile and cordless phones and change in cognitive function: a prospective cohort analysis of Australian primary school children.
Bhatt CR et al. · 2017
Long-term exposure to a continuous 900 MHz electromagnetic field disrupts cerebellar morphology in young adult male rats.
Aslan A, İkinci A, Baş O, Sönmez OF, Kaya H, Odacı E. · 2017
Researchers used three groups of six 21-day-old male rats, including an unexposed control, a sham-exposed group, and a group exposed to 900 MHz EMF for one hour daily from postnatal day 21 to 46. The EMF-exposed group had significantly fewer Purkinje cells than both the control and sham groups. Histopathological examination also showed altered Purkinje cell arrangement and intense cytoplasmic staining in the exposed rats.
Influence of the on-line ELF-EMF stimulation on the electrophysiological properties of the rat hippocampal CA1 neurons in vitro.
Zheng Y, Ma W, Dong L, Dou JR, Gao Y, Xue J. · 2017
Researchers studied the influence of on-line ELF-EMF stimulation on electrophysiological properties of rat hippocampal CA1 neurons in vitro. Modeling data and actual measurements showed similar magnetic flux densities from the stimulation coils. The stimulator induced sodium channel currents and field excitatory postsynaptic potentials in the neurons. Computational simulations in COMSOL modeling described the uniformity of the on-line magnetic field distribution.
Deep Brain Magnetic Stimulation Promotes Neurogenesis and Restores Cholinergic Activity in a Transgenic Mouse Model of Alzheimer's Disease.
Zhen J, Qian Y, Fu J, Su R, An H, Wang W , Zheng Y, Wang X. · 2017
Researchers investigated the effect of deep brain magnetic stimulation on spatial learning and memory, neurogenesis in the dentate gyrus, and cholinergic system expression and activity in a transgenic 5XFAD mouse model. Deep brain magnetic stimulation improved spatial learning and memory, enhanced neurogenesis in the hippocampal dentate gyrus, raised acetylcholine levels, and prevented increased acetylcholinesterase activity and decreased acetyltransferase activity in the hippocampus of 5XFAD mice. The authors concluded that deep brain magnetic stimulation may be a promising noninvasive tool for treating and preventing Alzheimer's disease cognitive impairment by promoting neurogenesis and enhancing cholinergic function.
Effects of Extremely Low-Frequency Electromagnetic Fields on Neurogenesis and Cognitive Behavior in an Experimental Model of Hippocampal Injury.
Sakhaie MH et al. · 2017
ELF-EMF exposure enhanced spatial learning and memory in the Morris water maze test. ELF-EMF significantly increased BrdU+ and NeuN+ cells in the dentate gyrus. Western blot showed NeuroD2 upregulation in ELF-EMF-exposed mice versus the TMT-treated group.
Dopamine-dependent changes of cortical excitability induced by transcranial static magnetic field stimulation in Parkinson's disease.
Dileone M et al. · 2017
Researchers performed a randomized double-blind sham-controlled cross-over study applying tSMS for 10 minutes to the more affected motor cortex of Parkinson's disease patients. Cortical excitability was measured by motor evoked potential amplitude elicited by single-pulse transcranial magnetic stimulation. tSMS significantly decreased MEP amplitudes in patients off dopaminergic medication but not in patients on levodopa. Between-patient variability of tSMS-induced changes was significantly greater when patients were on medication. Greater disease progression was associated with a switch from inhibitory to facilitatory plasticity on medication.
Static Magnetic Field Stimulation over Parietal Cortex Enhances Somatosensory Detection in Humans.
Carrasco-López C et al. · 2017
Researchers used noninvasive brain stimulation to modulate cortical network dynamics during neurophysiological and behavioral recordings. Parietal tSMS enhanced detection of near-threshold somatosensory stimuli. The improvement reflected decreased habituation to somatosensation. tSMS increased alpha oscillatory power without significantly affecting the early cortical component of somatosensory evoked potentials.
Rats exposed to 2.45GHz of non-ionizing radiation exhibit behavioral changes with increased brain expression of apoptotic caspase 3.
Varghese R, Majumdar A, Kumar G, Shukla A. · 2017
Researchers exposed female Sprague Dawley rats to 2.45GHz radiation for 4 hours per day for 45 days and assessed behavioral and oxidative stress parameters. Exposed rats exhibited memory decline and anxiety behavior in the Morris water maze, elevated plus maze, and light-dark box tests. Radiation exposure decreased brain antioxidant enzymes superoxide dismutase, catalase, and reduced glutathione, increased lipid peroxidation, and increased the apoptotic marker caspase 3, while histopathological examination and TNF-α levels showed no significant changes.
Effects of repeated restraint stress and WiFi signal exposure on behavior and oxidative stress in rats.
Othman H, Ammari M , Sakly M, Abdelmelek H. · 2017
Animals were divided into four groups: control, WiFi-exposed, restrained, and both WiFi-exposed and restrained, with each exposure occurring 2 h per day for 20 days. Tests included anxiety in the elevated plus maze, spatial learning in the water maze, cerebral oxidative stress response, and cholinesterase activity in brain and serum. WiFi exposure and restraint stress, alone and especially combined, induced anxiety-like behavior without impairing spatial learning and memory abilities. An oxidative stress response was triggered by WiFi and restraint, per se and especially when combined, as well as a WiFi-induced increase in acetylcholinesterase activity. There were no synergistic effects between WiFi signal and restraint stress on the brain.
Postnatal development and behavior effects of in-utero exposure of rats to radiofrequency waves emitted from conventional WiFi devices.
Othman H et al. · 2017
Researchers exposed pregnant rats to a 2.45 GHz WiFi signal for two hours daily throughout gestation. Offspring were assessed for physical and neurodevelopment during the first 17 postnatal days, anxiety at 28 days, motor behavior at 40-43 days, and cerebral oxidative stress and cholinesterase activity at 28 and 43 days. Prenatal WiFi exposure impaired early neurodevelopment but did not alter emotional or motor behavior in adulthood. It also increased oxidative stress markers and decreased antioxidant enzyme activities at 28 days but not at 43 days, and affected acetylcholinesterase activity in brain and serum.
The effect of 1800 MHz radio-frequency radiation on NMDA receptor subunit NR1 expression and peroxidation in the rat brain in healthy and inflammatory states.
Bodera P et al. · 2017
Researchers evaluated the effect of repeated 1800 MHz RFR exposure (5 times for 15 min) on NMDA-NR1 expression in rat brains in a persistent inflammatory state. They also measured the effect of RFR combined with tramadol to determine its potential antioxidant capacity. No differences in NMDA-NR1 expression were observed between baseline and RFR-exposed groups. NMDA-NR1 expression decreased after CFA injection combined with RFR exposure, while elevated expression was observed in healthy control rats exposed to RFR with or without tramadol. ORAC assessment revealed a robust effect of RFR, but other experiments showed equivocal effects.
Age-dependent acute interference with stem and progenitor cell proliferation in the hippocampus after exposure to 1800 MHz electromagnetic radiation.
Xu F et al. · 2017
Ten gigahertz microwave radiation impairs spatial memory, enzymes activity, and histopathology of developing mice brain
Sharma A, Kesari KK, Saxena VK, Sisodia R. · 2017
Effects of prenatal exposure to WIFI signal (2.45GHz) on postnatal development and behavior in rat: Influence of maternal restraint.
Othman H, Ammari M, Sakly M, Abdelmelek H. · 2017
Researchers randomly assigned 24 pregnant albino Wistar rats to four groups: control, WiFi-exposed, restrained, and both WiFi-exposed and restrained. Each WiFi exposure and restraint session lasted 2 hours per day throughout gestation until parturition. Prenatal WiFi exposure and restraint, separately and especially combined, adversely affected offspring physical development, neuromotor maturation, adult emotional responses, motor and exploratory behavior, brain oxidative stress, and serum biochemistry, with most impacts depending on offspring gender.
Effects of short and long term electromagnetic fields exposure on the human hippocampus
Deniz OG et al. · 2017
Researchers studied 60 healthy female medical students divided into low (<30 min daily) and high (>90 min daily) mobile phone exposure groups. Hippocampal volume and metabolite levels did not differ significantly between groups. However, the high exposure group performed significantly worse on Stroop and digit span backward tests of attention.
Personal radiofrequency electromagnetic field exposure measurements in Swiss adolescents.
Roser K et al. · 2017
Researchers measured personal RF-EMF exposure in 90 adolescents aged 13 to 17 years using a portable ExpoM-RF device across 13 frequency bands from 470 to 3600 MHz for three consecutive days with a time-activity diary. Mobile phones contributed 67.2% and mobile phone base stations contributed 19.8% of total personal RF-EMF measurements averaging 63.2 μW/m² (0.15 V/m). WLAN at school and home accounted for 3.5% of total personal measurements. Environmental sources contributed on average 6.0% to the brain dose and 9.0% to the whole-body dose according to dose calculations.
Effects of GSM and UMTS mobile telephony signals on neuron degeneration and blood-brain barrier permeation in the rat brain.
Poulletier de Gannes F et al. · 2017
Acute Neuroinflammation Promotes Cell Responses to 1800 MHz GSM Electromagnetic Fields in the Rat Cerebral Cortex.
Lameth J et al. · 2017
Researchers investigated whether a 2-hour head-only exposure to GSM-1800 MHz could affect a neuroinflammatory reaction triggered by lipopolysaccharide in 2-week-old or adult rats. In developing rats, 24 hours after exposure, cortical interleukin-1β and NOX2 NADPH oxidase transcripts were reduced by 50 to 60% compared with sham-exposed animals. Adult rats showed a 50% reduction in IL1β mRNA but no NOX2 suppression and displayed a significant growth response of microglial cell processes. GSM exposure decreased phosphorylation at two residues on the GluA1 AMPA receptor subunit (serine 831 and 845). The changes in gene expression, microglia, and GluA1 phosphorylation did not persist 72 hours after exposure and were absent without LPS pretreatment.
What This Means for You
- Children's developing brains may be more susceptible to EMF effects than adult brains.
- Limit screen time and device use, especially for younger children.
- Use speakerphone or wired headphones instead of holding phones to children's heads.
- Shield your child's phone with a radiation-deflecting pouch. SYB Phone Pouch
Further Reading:
Frequently Asked Questions
No study in this collection measured electromagnetic exposure against children's brain development directly. The supporting evidence is indirect: radiofrequency exposure produced DNA strand breaks in rat brain cells (Lai and Singh 1996), absorption-governing tissue properties differ with age (Peyman 2001), and prenatal phone exposure was associated with behavioral difficulties at age seven in a 13,159-child cohort whose authors caution the link may be non-causal (Divan 2008).
The physical basis is real but narrower than usually stated. Dielectric properties governing radiofrequency absorption decrease with age, most markedly in brain and skull tissue, because water content falls (Peyman 2001). That means young tissue interacts with these fields differently. Combined with a developing nervous system's smaller margin for error in repair, it is a reasonable basis for extra caution — not a measured multiplier for a child's absorbed dose.
No. The largest study of mobile phones and brain tumors, INTERPHONE, examined 2,708 glioma and 2,409 meningioma cases across 13 countries in adults and found no overall increase in risk, with suggestions at the highest exposure levels that its authors said bias and error prevent interpreting causally (INTERPHONE 2010). This collection contains no comparable pediatric tumor study.
Use the measures that reduce exposure at no cost: speaker mode or wired headphones instead of the phone at the ear, texting instead of calling where it makes no difference, devices out of bedrooms overnight, and wired connections for anything that stays put. These are worth doing on the strength of the evidence as it stands, and they remain sensible whichever way the science resolves.
Further Reading
For a comprehensive exploration of EMF health effects and practical protection strategies, explore these books by R Blank and Dr. Martin Blank.
