6,486 Studies Reviewed. 85.2% of Original Studies Found Biological Effects. The Evidence is Clear.
All Exposure Types

SAR (Specific Absorption Rate)

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Specific Absorption Rate (SAR) measures the rate at which RF energy is absorbed by body tissue, expressed in watts per kilogram (W/kg). SAR is used to rate cell phones and other devices held against the body. The FCC limit for cell phones is 1.6 W/kg averaged over 1 gram of tissue.

Concern Level Thresholds

Based on Building Biology Institute guidelines (W/kg (watts per kilogram)):

No Concern
< 0.4 W/kg
Slight Concern
0.4 – 1.0 W/kg
Severe Concern
1.0 – 1.6 W/kg
Extreme Concern
> 1.6 W/kg (FCC limit)

See where common exposures fall on the scale:

A logarithmic scale showing your reading relative to Building Biology concern thresholds and FCC regulatory limits.Your SAR Exposure in ContextNo ConcernSlightSevereExtreme0.0010.010.1FCC Limit →0.00110 W/kg

Showing 898 studies with measured sar (specific absorption rate) exposure

Modulator effects of L-carnitine and selenium on wireless devices (2.45 GHz)-induced oxidative stress and electroencephalography records in brain of rat

Naziroğlu M, Gümral N. · 2009

Researchers divided thirty rats into five groups to study the effects of 2.45 GHz electromagnetic radiation on the brain's antioxidant system and EEG records. Exposed rats received 2.45 GHz electromagnetic radiation for 60 minutes per day for 28 days, after which EEG records and brain cortex samples were collected. Brain cortex concentrations of vitamin A, vitamin C, and vitamin E were lower in the exposed group than in controls, though these concentrations were increased by selenium and L-carnitine supplementation. L-carnitine appeared to have a more protective effect on vitamin concentrations than selenium.

Brain & Nervous SystemNo Effects Found

Effects of weak mobile phone - electromagnetic fields (GSM, UMTS) on well-being and resting EEG.

Kleinlogel H et al. · 2008

Researchers tested 1950 MHz UMTS at SAR 0.1 and 1 W/kg and pulsed 900 MHz GSM at 1 W/kg on well-being and vigilance-controlled resting EEG in 15 healthy right-handed subjects. The study used a double-blind randomised crossover design. Neither UMTS nor GSM exposure produced significant changes in measured parameters compared to sham exposure. The results did not give evidence for a deleterious effect of the EMF on normal healthy mobile phone users.

Brain & Nervous SystemNo Effects Found

Effects of weak mobile Phone-Electromagnetic fields (GSM, UMTS) on well-being and resting EEG.

Kleinlogel H et al. · 2008

Researchers exposed 15 healthy adults to electromagnetic fields from both GSM (2G) and UMTS (3G) mobile phones while measuring their brain activity with EEG and asking about their well-being. They found no significant changes in brain wave patterns or reported symptoms compared to fake (sham) exposure. The study suggests that typical mobile phone radiation levels don't produce detectable immediate effects on brain activity in healthy users.

Brain & Nervous SystemNo Effects Found

Effects of weak mobile phone - electromagnetic fields (GSM, UMTS) on event related potentials and cognitive functions.

Kleinlogel H et al. · 2008

Researchers tested whether cell phone radiation from GSM and UMTS networks affects brain activity and cognitive performance in 15 healthy adults. They measured brain waves and reaction times during various mental tasks while participants were exposed to phone radiation at levels typical of actual phone use. The study found no significant changes in brain activity or cognitive function during EMF exposure compared to fake (sham) exposure.

Brain & Nervous SystemNo Effects Found

Effects of weak mobile phone - electromagnetic fields (GSM, UMTS) on event related potentials and cognitive functions.

Kleinlogel H et al. · 2008

Researchers tested the effects of 1950 MHz UMTS at 0.1 and 1 W/kg and pulsed 900 MHz GSM at 1 W/kg on event-related potentials and behavioral measures in 15 healthy right-handed subjects. The study used a double-blind, randomized, crossover design. Neither the UMTS- nor the GSM-EMF produced any significant changes in the measured parameters compared to sham exposure. The results do not give any evidence for a deleterious effect of the EMF on normal healthy mobile phone users.

DNA & Genetic DamageNo Effects Found

Analysis of gene expression in two human-derived cell lines exposed in vitro to a 1.9 GHz pulse-modulated radiofrequency field.

Chauhan V et al. · 2007

Researchers examined the effect of RF field exposure on late onset gene expression in U87MG cells after a 24 h exposure period. A human monocyte-derived cell line (MM6) was exposed to intermittent RF fields for 6 h and gene expression was assessed immediately and at 18 h postexposure. Both cell lines were exposed to 1.9 GHz pulse-modulated RF fields for 6 or 24 h at SARs of 0.1-10.0 W/kg. The study found no evidence that nonthermal RF field exposure altered gene expression in either U87MG or MM6 cells relative to nonirradiated controls. Heat shock at 43°C for 1 h altered the expression of well-characterized heat-shock proteins in both cell lines.

Modest increase in temperature affects ODC activity in L929 cells: low-level radiofrequency radiation does not.

Hoyto A, Sihvonen AP, Alhonen L, Juutilainen J, Naarala J · 2006

Researchers investigated the effects of low-level radiofrequency radiation and elevated temperature on ornithine decarboxylase (ODC) activity in murine L929 fibroblasts. RF radiation did not affect cellular ODC activity. A slight temperature increase of 0.8-0.9 degrees C in the exposure system led to decreased ODC activity, which was verified by exposing cells to different temperatures in incubators.

DNA & Genetic DamageNo Effects Found0

Microarray gene expression profiling of a human glioblastoma cell line exposed in vitro to a 1.9 GHz pulse-modulated radiofrequency field.

Qutob SS et al. · 2006

Researchers exposed U87MG glioblastoma cells to a 1.9 GHz pulse-modulated RF field for 4 hours at SARs of 0.1, 1.0, and 10.0 W/kg to assess global gene expression. No evidence was found that non-thermal RF fields affect gene expression in these cells compared to nonirradiated controls. Heat shock at 43°C for 1 hour up-regulated typical stress-responsive genes in the positive control group.

Investigation of potential effects of cellular phones on human auditory function by means of distortion product otoacoustic emissions.

Janssen T, Boege P, von Mikusch-Buchberg J, Raczek J. · 2005

Researchers investigated potential effects of electromagnetic fields from GSM cellular phones on outer hair cells by measuring distortion product otoacoustic emissions (DPOAEs) in 28 normally hearing subjects. No significant change in DPOAE level was found in response to EMF exposure. After compensating for undesired side effects, an extremely small exposure-correlated change of less than 1 dB was observed in some subjects, which the researchers suggested was physiologically irrelevant given the very large dynamic range of hearing in humans.

Effects of GSM-900 microwaves on DMBA-induced mammary gland tumors in female Sprague-Dawley rats.

Anane R et al. · 2003

Researchers tested whether whole-body exposure to GSM-900 microwaves affected tumor promotion and progression in female Sprague-Dawley rats with DMBA-induced mammary tumors. Results were negative for tumor latency, multiplicity, and volume, though in the first experiment tumor incidence was higher at 1.4 W/kg but less so at 2.2 W/kg and not at all at 3.5 W/kg. Overall the results were considered rather inconsistent and did not bring new evidence of a co-promoting effect of GSM-900 exposure.

DNA & Genetic DamageNo Effects Found

Genotoxic Potential of 1.6 GHz Wireless Communication Signal: In Vivo Two-Year Bioassay.

Vijayalaxmi, Sasser LB, Morris JE, Wilson BW, Anderson LE. · 2003

Timed-pregnant Fischer 344 rats and their nursing offspring were exposed to a far-field 1.6 GHz Iridium signal for 2 h/day, 7 days/week. The offspring then received chronic head-only near-field exposure to a 1.6 GHz signal for 2 h/day, 5 days/week over 2 years. Near-field exposures were conducted at brain SARs of 0.16 or 1.6 W/kg. The incidence of micronuclei in bone marrow did not differ significantly between exposed, sham-exposed, and cage control rats.

The effect of low level continuous 2.45 GHz waves on enzymes of developing rat brain.

Paulraj R, Behari J · 2002

Researchers exposed 35-day-old Wistar rats to low-level continuous 2.45 GHz microwaves for 2 hr/day over 35 days at a power density of 0.34 mW/cm2 with a specific absorption rate of 0.1 W/kg. Exposed rats showed a significant increase in calcium ion efflux and ornithine decarboxylase activity and a significant decrease in calcium-dependent protein kinase activity in brain tissue. The authors suggested that the radiation affects membrane-bound enzymes linked to cell proliferation and differentiation, indicating a possible tumor-promoting role.

DNA & Genetic DamageNo Effects Found

DNA damage and micronucleus induction in human leukocytes after acute in vitro exposure to a 1.9 GHz continuous-wave radiofrequency field

McNamee JP et al. · 2002

Researchers exposed human white blood cells to cell phone radiation (1.9 GHz) for 2 hours at various power levels to see if it would damage DNA or cause genetic abnormalities. They found no evidence of DNA damage or genetic changes at any exposure level tested, including levels 5 times higher than typical cell phone use. This Canadian government study suggests that short-term radiofrequency exposure may not directly harm genetic material in immune cells.

Disruption of a putative working memory task and selective expression of brain c-fos following microwave-induced hyperthermia

Mickley GA, Cobb BL, Mason PA, Farrell S · 1994

Researchers exposed rats to various doses of microwave radiation between training and testing to study effects on working memory. Memory was assessed by measuring relative exploration time of a familiar versus a new object, with extensive re-exploration of the familiar object indicating memory loss. Rats exposed to more than 5 W/kg developed hyperthermia, and microwave-exposed rats at doses of 1, 5, 8.5, 9.3, and 10 W/kg did not show a preference for the new object, unlike normothermic controls. Microwave hyperthermia evoked prominent c-fos expression in periventricular strata, hypothalamic nuclei, amygdala, and several cortical areas.

Neoplastic transformation of C3H/10T1/2 cells following exposure to 120-Hz modulated 2.45-GHz microwaves and phorbol ester tumor promoter.

Balcer-Kubiczek EK, Harrison GH. · 1991

Researchers exposed actively growing cultures of C3H/10T1/2 cells for 24 hours to 2.45-GHz microwaves pulse-modulated at 120 Hz. The electromagnetic fields alone had no effect on cell survival or induction of neoplastic transformation. When combined with the tumor promoter TPA, the enhancement of transformation was highly significant and ranged up to a level equivalent to that produced by 1.5 Gy of X rays. The frequency of neoplastic transformation was dependent on the level of electromagnetic exposure and was additive with doses of X rays given as a cocarcinogen.

Individual differences in the effects of mobile phone exposure on human sleep: Rethinking the problem

Loughran SP, McKenzie RJ, Jackson ML, Howard ME, Croft RJ. · 2012

Twenty volunteers each underwent two experimental nights in which they were randomly exposed to either an active or sham condition before a full night of sleep. EEG spectral power was increased in the sleep spindle frequency range in the first 30 minutes of non-REM sleep after active exposure. The increase was more prominent in participants who had already shown an increase in the original study, suggesting the effect is sensitive to individual variability.

Mutagenic response of 2.45 GHz radiation exposure on rat brain.

Kesari KK, Behari J, Kumar S. · 2010

Researchers exposed male Wistar rats to 2.45 GHz microwave radiation for 2 hours a day for 35 days at a power density of 0.34 mW/cm2. The whole brain tissue was dissected and used for study of double strand DNA breaks by micro gel electrophoresis and comet assay. Exposed brain cells showed a significant increase in comet head, tail length, and tail movement. The study concluded that chronic exposure to these radiations may cause significant damage to brain, which may be an indication of possible tumour promotion.

Reproductive HealthNo Effects Found

Effects of gestational exposure to 1.95‐GHz W‐CDMA signals for IMT‐2000 cellular phones: Lack of embryotoxicity and teratogenicity in rats

Ogawa K et al. · 2009

The study exposed four groups of pregnant CD(SD) IGS rats to a 1.95-GHz W-CDMA signal for 90 minutes daily on gestational days 7–17, with spatial average brain SARs of 0.67 and 2.0 W/kg for low and high exposure groups. On gestational day 20, all dams were killed by cesarean section and fetuses were evaluated for numbers of live, dead, and resorbed embryos, placental weights, sex ratios, fetal weights, and external, visceral, and skeletal abnormalities. Maternal body weight gain did not differ between groups, and no adverse effects were observed on any reproductive or embryotoxic parameters.

The effect of mobile phone electromagnetic fields on the alpha rhythm of human electroencephalogram.

Croft RJ et al. · 2008

Researchers tested 120 healthy participants in a double-blind, counterbalanced crossover design, with each person receiving a 30-minute active and a 30-minute sham exposure one week apart while EEG data were recorded. The purpose of the study was to test one of the strongest findings in the literature, that of increased alpha power in response to MP-type radiation. Overall alpha power was enhanced during exposure, with the effect larger at sites on the same side as the exposure source than on the opposite side over posterior regions. After exposure ended, no overall change to alpha power was observed, though there was less alpha power contralateral to the exposure source relative to the ipsilateral side.

Brain & Nervous SystemNo Effects Found

The sensitivity of human event-related potentials and reaction time to mobile phone emitted electromagnetic fields.

Hamblin DL, Croft RJ, Wood AW, Stough C, Spong J. · 2006

Researchers tested 120 participants in a double-blind, counterbalanced, crossover design with two sessions one week apart. In both sessions, participants performed auditory and visual oddball tasks while EEG was recorded with a mobile phone set to sham exposure mounted over the temporal region, and then performed the same tasks while the handset was set to active or sham. No significant differences were found between exposure conditions for any ERP component or reaction time.

Disturbance of cell proliferation in response to mobile phone frequency radiation.

Trosić I, Pavicić I. · 2009

The study aimed to determine the influence of mobile phone frequency radiation on proliferation, cytoskeleton structure, and mitotic index of V79 cells after 1, 2, and 3 hours of exposure. V79 cells were exposed to continuous-wave 935 MHz radiation at an electric field strength of (8.2+/-0.3) V m(-1) and a specific absorption rate of 0.12 W kg(-1). Cell proliferation declined in cells exposed for three hours when measured 72 hours after irradiation. Microtubule structure was clearly altered immediately after three hours of irradiation. The mitotic index in exposed cells did not differ from negative controls.