Biochemical Modifications and Neuronal Damage in Brain of Young and Adult Rats After Long-Term Exposure to Mobile Phone Radiations.
Motawi TK, Darwish HA, Moustafa YM, Labib MM. · 2014
At a Glance
Of the 473 peer-reviewed studies in this collection on mobile phone radiation, 335 — 70.8% — reported biological effects. None identifies a safe age. The research speaks to how a phone is used rather than when a child gets one: distance from the head, call duration, and whether the device transmits at full power. The tissue basis for extra caution with children is measured, and the largest study of phones and brain tumors found no overall increase in risk.
Based on analysis of 491 peer-reviewed studies
Parents frequently ask at what age children should get their first cell phone. Beyond social and developmental considerations, there are scientific factors to consider regarding children's unique vulnerability to radiofrequency radiation.
Children are not miniature adults when it comes to RF exposure. Research has documented that children's thinner skulls, higher brain water content, and developing nervous systems result in different exposure patterns than adults experience from the same devices.
This page examines the research relevant to children's cell phone use and what science suggests about age-appropriate exposure.
Key Findings
- -335 of 473 studies (70.8%) in this collection found biological effects from mobile phone radiation exposure
- -No study here identifies a safe age — the evidence addresses exposure conditions, not an age threshold
- -Tissue dielectric properties decrease with age, most markedly in brain and skull, the measured basis for expecting children to absorb differently than adults (Peyman 2001)
- -Radiofrequency exposure produced DNA strand breaks in rat brain cells at a whole-body absorption rate of 1.2 W/kg (Lai and Singh 1996)
- -The largest brain-tumor study found no overall increased risk across 2,708 glioma and 2,409 meningioma cases in 13 countries, with a suggestion at the highest exposures that its authors said bias prevents interpreting causally (INTERPHONE 2010)
What the Research Shows
What the Research Can Answer
Of the 473 peer-reviewed studies indexed here on mobile phone radiation, 335 — 70.8% — reported measurable biological effects. None of them was designed to find an age at which a phone becomes safe, and none reports one. The research addresses exposure — how much energy reaches which tissue, under what conditions — which makes it useful for deciding how a child uses a phone rather than when they get one.
Why Age Matters Physically
Peyman and colleagues (2001) measured dielectric properties across ten rat tissues at six ages from 130 MHz to 10 GHz and found a general decrease with age, most apparent in brain, skull and skin, driven by falling water content. Those properties determine how radiofrequency energy enters and deposits in tissue, so a younger head interacts with a phone's field differently than an adult's. The study measured rat tissue and reports properties rather than a child's absorbed dose, which is the correct strength for this claim: directionally supported, not quantified.
What Exposure Does
Lai and Singh (1996) exposed rats at 2 mW/cm², a whole-body specific absorption rate of 1.2 W/kg, and found increased single- and double-strand DNA breaks in brain cells four hours later, with pulsed and continuous-wave exposure producing similar effects.
Divan and colleagues (2008) followed 13,159 children in the Danish National Birth Cohort and found that both prenatal and, to a lesser degree, postnatal phone exposure were associated with emotional and hyperactivity problems around school entry. Their own caution belongs with the finding: the associations may be non-causal and may be due to unmeasured confounding.
The Null Result Parents Should See
The INTERPHONE study examined 2,708 glioma and 2,409 meningioma cases with matched controls across 13 countries. It found no overall increase in brain tumor risk among mobile phone users, reporting reduced odds ratios its authors attributed to participation bias or methodological limitations, alongside suggestions of increased glioma risk at the highest exposure levels that bias and error prevent interpreting causally. The study covers adults, and it is the most substantial evidence against a tumor risk from ordinary use.
What Actually Changes Exposure
Four things, none of which depend on a birthday. Distance from the head, since intensity falls steeply within the first few centimeters — speaker mode or wired headphones remove most of it. Call duration, since absorbed energy accumulates with transmit time. Signal strength, because a phone reaching for a distant tower transmits at higher power than one with full bars. And whether the device is transmitting at all, which is why texting, airplane mode and leaving the phone out of the bedroom overnight matter more than the model.
What This Does Not Establish
Nothing here shows that a child of any particular age is harmed by a phone. The DNA evidence is animal work at exposures above ordinary use. The behavioral cohort measures recalled use and carries the confounding its authors name. The largest tumor study is null. A specific safe age does not follow from this body of work.
How to Use This in a Decision
The age at which a child gets a phone is mostly a question about supervision, social readiness and sleep, and this collection has nothing to say about those. What it supports is the conditions attached to the device whenever it arrives: headphones or speaker for calls, texting as the default, no phone in the bedroom overnight, airplane mode when the device is being used as a camera or game, and a wired or WiFi connection rather than cellular where possible. Those conditions cost nothing and address the exposure variables the research actually measured.
Related Studies (491)
Behavior and memory evaluation of Wistar rats exposed to 1·8 GHz radiofrequency electromagnetic radiation
Júnior LC et al. · 2014
Researchers exposed male Wistar rats to radiofrequency electromagnetic radiation from a GSM cell phone (1·8 GHz) for 3 days. After exposure, behavioral tests including the open field and object recognition tests were performed. The exposed animals did not present anxiety patterns or working memory impairment, but stress behavior actions were observed.
Liver antioxidant stores protect the brain from electromagnetic radiation (900 and 1800 MHz)-induced oxidative stress in rats during pregnancy and the development of offspring.
Cetin H et al. · 2014
Researchers divided thirty-two rats and their offspring into three groups: a control group, a 900 MHz group, and an 1800 MHz group, with the two exposed groups receiving electromagnetic radiation for 60 minutes per day during pregnancy and neonatal development. Brain and liver glutathione peroxidase activities, as well as liver vitamin A and beta-carotene concentrations, decreased in the exposed groups. Brain iron, vitamin A, and beta-carotene concentrations increased in the exposed groups, and by the sixth week, selenium concentrations in the brain decreased in the exposed groups. There were no statistically significant differences in glutathione, vitamin E, chromium, copper, magnesium, manganese, and zinc concentrations between the three groups.
Cancer & Tumors
Not an original health-effects study
New Zealand adolescents' cellphone and cordless phone user-habits: are they at increased risk of brain tumours already? A cross-sectional study.
Redmayne M · 2013
The cross-sectional study recruited 373 Year 7 and 8 students with a mean age of 12.3 years from the Wellington region of New Zealand. Participants completed a questionnaire and measured their normal body-to-phone texting distances. Both cellphones and cordless phones were used by approximately 90% of students. A third of participants had already used a cordless phone for ≥ 7 years. High cellphone use was related to cellphone location at night, being woken regularly, and being tired at school.
Cellular EffectsNo Effects Found
Electromagnetic fields (UHF) increase voltage sensitivity of membrane ion channels; possible indication of cell phone effect on living cells.
Ketabi N, Mobasheri H, Faraji-Dana R. · 2013
Researchers investigated the effects of ultra high frequency nonionizing electromagnetic fields on the channel activities of the nanopore forming protein OmpF porin. Using the voltage clamp technique on an artificial bilayer, they exposed the pore to electromagnetic fields at 910 to 990 MHz and found that the frequency of channel gating and voltage sensitivity increased, while conductance remained unchanged. No changes in membrane capacitance or permeability were identified, and the energy transferred to nano-environments was estimated to address possible thermal effects.
Symptoms & SensitivityNo Effects Found
Subjective symptoms related to GSM radiation from mobile phone base stations: a cross-sectional study.
Gómez-Perretta C, Navarro EA, Segura J, Portolés M. · 2013
Researchers re-analyzed data from a 2003 study on health symptoms related to microwave exposure from mobile phone base stations. They used binary logistic regression with bootstrapping to model symptoms as a function of exposure. The symptoms most related to exposure were lack of appetite, lack of concentration, irritability, and trouble sleeping. Concerns about base stations were strongly related to trouble sleeping. The exposure variable remained statistically significant in multivariate analysis.
Brain & Nervous SystemNo Effects Found
No effects of a single 3G UMTS mobile phone exposure on spontaneous EEG activity, ERP correlates, and automatic deviance detection
Trunk A et al. · 2013
Researchers conducted two double-blind experiments to test effects of a 30-minute 3G UMTS mobile phone-like EMF exposure on human brain electrical activity. In the first experiment with 17 participants, spontaneous EEG spectral power was analyzed in delta, theta, alpha, and beta bands before and after exposure while subjects watched a silent documentary. In the second experiment with 26 participants, auditory event-related potentials and mismatch negativity were measured using a passive oddball paradigm with standard and deviant tones. No measurable effects were found on EEG spectral power in any frequency band. No significant effects were found on the amplitude and latency of ERP components including P50, N100, P200, MMN, and P3a.
Sleep & Circadian RhythmNo Effects Found
Effects of electromagnetic fields emitted from W-CDMA-like mobile phones on sleep in humans.
Nakatani-Enomoto S et al. · 2013
Researchers exposed 19 volunteers to real or sham electromagnetic fields for 3 h before sleep on three consecutive days in a double-blind design. No significant differences were found in subjective feelings, sleep stage percentages, or EEG power spectra between real and sham exposures. The researchers concluded that the exposure had no detectable effects on human sleep.
Brain & Nervous SystemNo Effects Found
No increased sensitivity in brain activity of adolescents exposed to mobile phone-like emissions
Loughran SP et al. · 2013
Researchers used a double-blind, randomized, crossover design with 22 adolescents aged 11–13 years. Participants underwent three sessions with mobile phone-like RF EMF signals at two intensities and a sham session. No clear significant effects of RF EMF exposure were found on waking EEG or cognitive performance.
Brain & Nervous SystemNo Effects Found
Maternal cell phone and cordless phone use during pregnancy and behaviour problems in 5-year-old children
Guxens M et al. · 2013
Researchers assessed the association between maternal cell phone and cordless phone use during pregnancy and teacher-reported and maternal-reported child behaviour problems at age 5. A total of 2618 children were included in the study. Prenatal cell phone use showed an increased but non-significant association with teacher-reported overall behaviour problems, without a dose-response relationship. Cordless phone use showed odds ratios below 1 or close to unity for teacher-reported overall behaviour problems. Associations with maternal-reported overall behaviour problems and specific behaviour problem subscales were non-significant.
Brain & Nervous SystemNo Effects Found
In Situ Expression of Heat-Shock Proteins and 3-Nitrotyrosine in Brains of Young Rats Exposed to a WiFi Signal In Utero and In Early Life
Aït-Aïssa S et al. · 2013
Researchers investigated bioeffects of WiFi signals on developing nervous systems of young rodents by assessing expression levels of 3-Nitrotyrosine, Hsp25, and Hsp70. Daily 2-hour exposures were performed blind in a reverberation chamber at whole-body specific absorption rates of 0, 0.08, 0.4, and 4 W/kg. No significant difference was observed among exposed and sham-exposed groups. The results suggest repeated WiFi exposure during gestation and early life has no deleterious effects on young rat brains.
Complexities of sibling analysis when exposures and outcomes change with time and birth order.
Sudan M, Kheifets LI, Arah OA, Divan HA, Olsen J. · 2013
The study demonstrated complexities of performing a sibling analysis with a re-examination of associations between cell phone exposures and behavioral problems in the Danish National Birth Cohort. The association of behavioral problems with prenatal and postnatal exposure differed between siblings (OR: 1.07; 95% CI: 0.69-1.66) and non-siblings (OR: 1.54; 95% CI: 1.36-1.74). Within siblings, the association was strongest for first-born children (OR: 1.72; 95% CI: 0.86-3.42) and negative for later-born children (OR: 0.63; 95% CI: 0.31-1.25). The study included 52,680 children, including 5,441 siblings, followed up to age 7. Researchers estimated associations between cell phone exposures and behavioral problems while accounting for the random family effect among siblings.
Association between Problematic Cellular Phone Use and Suicide: The Moderating Effect of Family Function and Depression.
Wang PW, Liu TL, Ko CH, Lin HC, Huang MF, Yeh YC, Yen CF. · 2013
The study examined the association between problematic CPU and suicidal ideation and attempts in 5051 adolescents. About 10.54% of adolescents had problematic CPU, with suicidal ideation rates of 23.50% versus 11.76% and attempt rates of 13.70% versus 5.45%. Family function, but not depression, had a moderating effect on the association between problematic CPU and suicidal ideation and attempt.
Cancer & Tumors163 citations
Case-control study of the association between malignant brain tumours diagnosed between 2007 and 2009 and mobile and cordless phone use.
Hardell L, Carlberg M, Söderqvist F, Mild KH. · 2013
Researchers conducted a case-control study of brain tumour cases aged 18-75 diagnosed from 2007 to 2009, with one population-based control matched on gender and age per case. Among malignant brain tumour cases, 87% participated, and 85% of controls answered the questionnaire. Analogue mobile phone use had an odds ratio of 1.8, which increased to 3.3 with more than 25 years of latency. Digital 2G mobile phone use showed an odds ratio of 1.6, rising to 2.1 with latency over 15-20 years. Cordless phone use had an odds ratio of 1.7, increasing to 2.1 with 15-20 years latency.
Meningioma patients diagnosed 2007--2009 and the association with use of mobile and cordless phones: a case--control study.
Carlberg M, Söderqvist F, Hansson Mild K, Hardell L. · 2013
The study included 709 meningioma cases diagnosed during 2007-2009 and 1,368 control subjects who answered a questionnaire. Mobile phone use overall gave an odds ratio of 1.0 (95% CI 0.7-1.4) and cordless phone use gave 1.1 (95% CI 0.8-1.5). Risk increased significantly per 100 hours of cumulative use, with the highest odds ratio in the fourth quartile (>2,376 hours). No statistically significant increased risk was found for ipsilateral use, temporal lobe tumors, or per year of latency. Tumor volume was not related to latency or cumulative use.
Mobile phone use, blood lead levels, and attention deficit hyperactivity symptoms in children: a longitudinal study.
Byun YH et al. · 2013
Researchers conducted a longitudinal study of 2,422 children in 10 Korean cities to examine the association between mobile phone use and ADHD symptoms while considering lead exposure. They found that mobile phone use for voice calls was linked to higher ADHD symptom risk, but only among children with relatively high lead exposure. The results suggest that simultaneous exposure to lead and RF from mobile phone use was associated with increased ADHD symptom risk, though reverse causality could not be excluded.
Cancer & Tumors184 citations
Mobile phone use and risk of brain neoplasms and other cancers: prospective study
Benson VS et al. · 2013
Researchers examined the relation between mobile phone use and incidence of intracranial CNS tumours and other cancers in 791,710 middle-aged women in the UK Million Women Study. During 7 years' follow-up, 51,680 incident invasive cancers and 1,261 incident intracranial CNS tumours occurred. Risk among ever versus never users was not increased for all intracranial CNS tumours (RR = 1.01, 95% CI = 0.90-1.14, P = 0.82) nor for cancer at 18 other specified sites. For long-term users compared with never users, there was no appreciable association for glioma (10+ years: RR = 0.78, 95% CI = 0.55-1.10, P = 0.16) or meningioma (10+ years: RR = 1.10, 95% CI = 0.66-1.84, P = 0.71).
Specific absorption rate variation in a brain phantom due to exposure by a 3G mobile phone: problems in dosimetry.
Behari J, Nirala JP. · 2013
A SAR measurement system was developed for a brain phantom in a Perspex box. The phantom box volume matched a small rat and was illuminated by a 3G mobile phone at 1718.5 MHz. A moving platform changed the phone's angular position at 2 degrees per minute up to 20 degrees while induced fields were measured. SAR values computed from induced fields were higher than those from induced field measurements alone and varied with angular position, but remained well below human safety criteria. SAR was also measured by temperature rise and compared with the induced-field results, and measurements were repeated in a 10 g phantom in a cubical box for safety criteria comparison.
Mobile phone emissions modulate brain excitability in patients with focal epilepsy
Tombini M et al. · 2013
Researchers used transcranial magnetic stimulation to assess the effects of 45 minutes of GSM-EMF exposure on cortical excitability in ten patients with cryptogenic focal epilepsy originating outside the primary motor area. The study employed a crossover, double-blind, counter-balanced design with three sessions one week apart. Exposure over the hemisphere contralateral to the epileptic focus significantly increased excitability in that hemisphere and slightly decreased it in the ipsilateral hemisphere. Real or sham exposure over the ipsilateral hemisphere did not affect brain excitability.
Cell phone exposures and hearing loss in children in the Danish National Birth Cohort
Sudan M, Kheifets L, Arah OA, Olsen J. · 2013
The Danish National Birth Cohort enrolled pregnant women from 1996 to 2002 and conducted detailed interviews at multiple time points up to age 7. Researchers used three statistical methods to examine cell phone use at age 7 in relation to hearing loss at age 7. Weak associations were observed, with odds ratios of 1.21, 1.23, and 1.22 from the three models. The authors cautioned that biases could affect the findings and that the results are not sufficient to conclude an effect of cell phone exposures on hearing.
The relationship between adolescents' well-being and their wireless phone use: a cross-sectional study
Redmayne M, Smith E, and Abramson MJ · 2013
More frequent cellphone and cordless phone calls were associated with higher odds of headaches, wired headsets with tinnitus, wireless headsets with headache, feeling down or depressed, and waking at night, and being woken by a cellphone at night was strongly linked to daytime tiredness. The study reported that 36% of tested associations were statistically significant, more than the 5% expected by chance, and several showed dose-dependent patterns.
Auditory Brainstem Responses and EMFs Generated by Mobile Phones.
Khullar S1, Sood A2, Sood S3 · 2013
Researchers recruited 60 subjects and divided them into three groups of 20 based on mobile phone usage duration. Group A served as controls, group B used phones for up to 30 minutes daily for 5 years, and group C used phones for up to 30 minutes daily for 10 years. Auditory brainstem responses were recorded and analyzed for wave latencies and interpeak latencies. No significant difference in ABR parameters was found between controls and the 5-year use group. Wave latencies were significantly prolonged in the 10-year use group compared to controls.
Interference of vitamin E on the brain tissue damage by electromagnetic radiation of cell phone in pregnant and fetal rats
Gao X, Luo R, Ma B, Wang H, Liu T, Zhang J, Lian Z, Cui X · 2013
Radiation exposure decreased SOD and GSH-Px activity and increased MDA levels in both pregnant and fetal rats, and caused mitochondrial swelling, edema, and chromatin condensation in fetal brain tissue. Vitamin E supplementation reversed these changes in a dose-dependent manner, with all three doses increasing SOD and GSH-Px in fetal rats, and middle and high doses decreasing MDA in fetal rats and high dose doing so in pregnant rats.
Effect of a single 30 min UMTS mobile phone‐like exposure on the thermal pain threshold of young healthy volunteers.
Vecsei Z, Csathó A, Thuróczy G, Hernádi I · 2013
Researchers tested the effects of UMTS RF EMF exposure on the thermal pain threshold of 20 young adult volunteers, measuring responses on the surface of the fingers. The exposure lasted 30 minutes and was applied to the head through a patch antenna, with SAR kept constant at 1.75 W/kg. Thermal pain thresholds were intact, but a reduced desensitization effect between repeated stimulations was observed on the contralateral side during genuine UMTS exposure. Subjective pain ratings were marginally decreased in the genuine exposure condition only.
Transient and cumulative memory impairments induced by GSM 1.8 GHz cell phone signal in a mouse model
Ntzouni MP et al. · 2013
What This Means for You
- Consider delaying smartphone access until at least age 12-13, consistent with pediatric recommendations.
- When children do use phones, encourage speakerphone and limit duration of calls.
- Keep phones out of bedrooms at night to reduce overnight exposure.
- Use a radiation-shielding phone pouch when carrying the phone. SYB Phone Pouch
Further Reading:
Frequently Asked Questions
No study in this collection identifies a safe age, and none was designed to. The radiation evidence addresses exposure conditions — distance from the head, call duration, signal strength, transmit time — rather than an age threshold. The age decision rests mainly on supervision, social readiness and sleep, which this research does not speak to. What it supports is attaching usage conditions to the phone whenever the child gets one.
The measured basis is tissue properties rather than a child-specific dose study. Dielectric properties governing radiofrequency absorption decrease with age, most markedly in brain and skull tissue, because water content is higher in younger tissue (Peyman 2001). A smaller head also places the transmitting antenna relatively closer to more of the brain. Both support extra caution without providing a number for how much more a child absorbs.
The evidence does not support that claim. The largest study of mobile phone use and brain tumors, INTERPHONE, examined over 5,000 tumor cases across 13 countries and found no overall increase in risk, with a suggestion at the highest exposure levels its authors said bias and error prevent interpreting causally (INTERPHONE 2010). That study covers adults; this collection holds no comparable pediatric tumor study.
The ones that target what the research measures. Calls on speaker or wired headphones rather than the phone at the ear. Texting as the default. No phone in the bedroom overnight, which addresses both exposure and sleep. Airplane mode when the device is a camera, a game or a music player. And a preference for WiFi over cellular in weak-signal areas, since a phone straining to reach a tower transmits harder.
Further Reading
For a comprehensive exploration of EMF health effects and practical protection strategies, explore these books by R Blank and Dr. Martin Blank.
