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.
Based on Building Biology Institute guidelines (W/kg (watts per kilogram)):
See where common exposures fall on the scale:
Showing 871 studies with measured sar (specific absorption rate) exposure
Atlı Şekeroğlu Z, Akar A, Sekeroğlu V. · 2013
Researchers exposed young and adult rats to cell phone radiation (900 MHz) for 2 hours daily over 45 days. Both age groups showed significant DNA damage in bone marrow cells, with young rats more severely affected. The genetic damage persisted even after a recovery period.
Adair ER, Kelleher SA, Mack GW, Morocco TS, · 1998
Researchers exposed seven people to 450 MHz radio waves for 45 minutes to study heat effects. The RF energy increased sweating but participants' bodies successfully maintained normal core temperature through natural cooling. This shows human thermoregulation can handle these RF exposure levels effectively.
La Regina M et al. · 2003
Researchers exposed 480 rats to cell phone radiation for 4 hours daily over 2 years to see if it caused cancer. They tested two types of signals (FDMA and CDMA) at levels similar to what your brain absorbs during phone calls. The study found no increase in tumors of any type compared to unexposed rats.
Canseven AG, Esmekaya MA, Kayhan H, Tuysuz MZ, Seyhan N. · 2014
Researchers exposed Burkitt's lymphoma cells (a type of cancer cell) to 1.8 GHz microwave radiation at levels similar to cell phones for 24 hours. The radiation significantly increased cell death and reduced cell survival, and when combined with a cancer drug called Gemcitabine, the effects were even stronger. This suggests that microwave radiation can affect cancer cells in ways that might interact with cancer treatments.
Loughran SP et al. · 2013
Researchers exposed 22 adolescents (ages 11-13) to cell phone-like radiation at two different power levels for 30 minutes while measuring brain activity and cognitive performance. They found no significant effects on brain waves or thinking abilities compared to fake exposure sessions. This suggests adolescents may not be more sensitive to mobile phone radiation than previously thought.
Trosic I, Busljeta I. · 2006
Researchers exposed rats to WiFi-frequency radiation (2.45 GHz) for 2 hours daily over weeks. The exposure initially damaged blood cells and disrupted bone marrow production, but effects normalized by study's end, suggesting rats may adapt to chronic microwave exposure.
Sekeroğlu V, Akar A, Sekeroğlu ZA · 2012
Researchers exposed young and adult rats to cell phone radiation (1800 MHz) for two hours daily over 45 days. Both groups showed DNA damage in bone marrow cells, but young rats suffered significantly worse damage that didn't heal during recovery, suggesting children may be more vulnerable.
Unterlechner M, Sauter C, Schmid G, Zeitlhofer J · 2008
Researchers exposed 40 healthy adults to 3G mobile phone signals at 1.97 GHz for 90 minutes while testing their attention and reaction time through computer tasks. The study found no immediate effects on cognitive performance at exposure levels up to 0.63 W/kg SAR (specific absorption rate), which represents the amount of RF energy absorbed by brain tissue. This suggests that short-term exposure to 3G phone signals does not impair basic mental functions like attention and reaction speed.
Schmid G, Sauter C, Stepansky R, Lobentanz IS, Zeitlhofer J · 2005
Researchers exposed 58 healthy adults to UMTS (3G) mobile phone signals at levels similar to actual phone use and tested whether this affected their visual perception through four different eye tests. They found no measurable differences in visual performance between exposure to the radio frequency signals and fake (sham) exposure. This suggests that 3G mobile phone radiation at typical usage levels does not impair basic visual processing abilities.
Ozgur E, Güler G, Seyhan N. · 2010
Researchers exposed guinea pigs to cell phone radiation (1800 MHz) for 10-20 minutes daily and found it caused liver damage through oxidative stress. Antioxidants like N-acetyl cysteine and green tea extract provided protection, suggesting cell phone radiation may harm organs beyond the brain.
Ozgur E, Güler G, Seyhan N · 2010
Guinea pigs exposed to cell phone radiation (1800 MHz) for 10-20 minutes daily showed liver damage from oxidative stress, with longer exposure causing more harm. However, antioxidants N-acetyl cysteine and green tea extract provided significant protection against this cellular damage.
Şahin D et al. · 2016
Researchers exposed female rats to 3G mobile phone radiation (2100 MHz) for either 10 or 40 days to study DNA damage in brain tissue. They found increased DNA damage after 10 days of exposure, but surprisingly, this damage decreased after 40 days, suggesting the brain may develop protective mechanisms over time. The study used radiation levels similar to what you'd experience during heavy mobile phone use.
Ozgur E et al. · 2015
Scientists exposed guinea pigs to cell phone radiation (900 MHz) for seven days and found it significantly reduced SOD, a protective antioxidant enzyme in liver tissue. Surprisingly, two common antioxidant supplements caused cellular damage when used alone, showing radiation's complex effects on cellular protection.
Ozgur E et al. · 2014
Researchers exposed guinea pigs to 900 MHz cell phone radiation for 7 days and measured damage to liver tissue. The radiation significantly reduced the activity of an important antioxidant enzyme (superoxide dismutase) that protects cells from damage. Surprisingly, two antioxidant supplements that were meant to provide protection actually caused additional cellular damage when combined with radiation exposure.
Schneider J, Stangassinger M · 2014
German researchers exposed rats to cell phone radiation (900 MHz GSM and 1.966 GHz UMTS) for their entire lives and tested their memory using a social recognition task. Male rats showed significant memory impairments, particularly when exposed to GSM frequencies, while female rats were unaffected. This suggests that chronic exposure to cell phone radiation at levels similar to what phones emit can damage memory function in a sex-specific way.
Hinrikus H, Lass J, Karai D, Pilt K, Bachmann M. · 2014
Researchers tested whether low-level microwave radiation affects how substances move through water by setting up two water containers connected by a tube and measuring how salt spread between them. They found that 450 MHz microwaves at 0.4 W/kg made diffusion happen 1.7 times faster, even though water temperature stayed constant. This suggests microwaves can alter water's molecular structure in ways that go beyond simple heating effects.
Avci B, Akar A, Bilgici B, Tunçel ÖK · 2012
Researchers exposed rats to cell phone-level radiation (1.8 GHz) for one hour daily for three weeks and found it caused protein damage in brain tissue. The study also tested whether garlic extract could protect against this damage and found it significantly reduced the brain protein damage caused by the radiation. This suggests that cell phone radiation can harm brain proteins, but certain antioxidants may offer some protection.
Lu YS, Huang BT, Huang YX. · 2012
Researchers exposed human immune cells to 900 MHz cell phone radiation for eight hours at typical usage levels. The radiation killed 37% of immune cells by triggering harmful molecules called free radicals, demonstrating that everyday phone exposure can damage your immune system.
Avci B, Akar A, Bilgici B, Tunçel ÖK. · 2012
Researchers exposed rats to 1.8 GHz radiofrequency radiation (similar to cell phone frequencies) for one hour daily over three weeks at levels comparable to phone use. The radiation caused protein damage in brain tissue and increased nitric oxide levels in blood, indicating oxidative stress. When rats were given garlic extract alongside the radiation exposure, the brain protein damage was significantly reduced.
De Iuliis GN, Newey RJ, King BV, Aitken RJ. · 2009
Researchers exposed human sperm to cell phone radiation at 1.8 GHz frequencies. Higher radiation levels reduced sperm movement and survival while increasing DNA damage and harmful molecules. The findings suggest that heavy mobile phone use could potentially affect male fertility and future children's health.
Ogawa K et al. · 2009
Researchers exposed pregnant rats to cell phone radiation (1.95-GHz signals) for 90 minutes daily during pregnancy to see if it would harm developing babies. They tested different exposure levels, including some higher than typical cell phone use, and found no effects on pregnancy outcomes, fetal development, or birth defects. The study suggests that cell phone radiation at these levels doesn't appear to cause developmental problems during pregnancy.
De Iuliis GN, Newey RJ, King BV, Aitken RJ. · 2009
Researchers exposed human sperm cells to radiofrequency radiation at the same frequency used by mobile phones (1.8 GHz) for 24 hours in laboratory conditions. They found that as radiation levels increased, sperm became less mobile and viable, while also showing increased DNA damage and harmful cellular stress. This suggests that mobile phone radiation could potentially affect male fertility and even the health of future children.
Ziemann C et al. · 2009
Researchers exposed mice to cell phone radiation (GSM and DCS signals) for 2 hours daily, 5 days a week for two years to test whether it damages DNA. They measured micronuclei (small DNA fragments that indicate genetic damage) in blood cells and found no difference between exposed and unexposed mice. This suggests that chronic exposure to these specific cell phone frequencies at the tested levels did not cause detectable genetic damage in this animal model.
Hruby R, Neubauer G, Kuster N, Frauscher M · 2008
Researchers exposed rats to 902 MHz GSM-type wireless signals (similar to cell phone radiation) for 4 hours daily over 6 months after giving them a chemical known to cause breast cancer. The RF-exposed rats showed statistically significant increases in palpable tissue masses and more malignant tumors compared to sham-exposed controls, though the researchers concluded these differences were likely incidental due to high variability in the cancer model used.
Mathur R · 2008
Researchers exposed growing rats to AM radio frequency fields (similar to some communication systems) for 2 hours daily over 45 days and tested their pain responses. The exposed rats showed altered pain processing - they became more emotionally reactive to short-term pain but less sensitive to long-term pain. This suggests that chronic RF exposure during development can rewire how the nervous system processes different types of pain signals.