Radio frequency electromagnetic fields are produced by wireless communication devices and broadcast signals. They range from about 3 kHz to 300 GHz and include frequencies used by cell phones, WiFi, Bluetooth, and 5G. RF is typically measured in microwatts per square meter (µW/m²) or milliwatts per square centimeter (mW/cm²).
Based on Building Biology Institute guidelines (µW/m² (microwatts per square meter)):
See where common exposures fall on the scale:
Showing 376 studies with measured radio frequency (rf) exposure
Kolomytseva MP, Gapeev AB, Sadovnikov VB, Chemeris NK. · 2002
Russian scientists exposed mice to 42 GHz radiation for 20 minutes daily and found it suppressed infection-fighting white blood cells by 50% after just one exposure. Five days of exposure increased total white blood cell count by 44%, suggesting millimeter waves disrupt immune function.
Lushnikov KV, Gapeev AB, Sadovnikov VB, Cheremis NK. · 2001
Russian researchers exposed mice to 42 GHz radiation (millimeter waves like those in 5G) at low power levels. After 20 days of daily exposure, immune organs shrank significantly - the thymus by 17.5% and spleen by 14.5%, suggesting prolonged millimeter wave exposure may weaken immune system function.
Lushnikov et al. · 2001
Researchers exposed mice to weak 42 GHz electromagnetic radiation daily for 20 days. While short exposures showed no effects, prolonged exposure significantly reduced immune organ cell counts - thymus cells dropped 17.5% and spleen cells 14.5%, suggesting repeated EMF exposure may weaken immune function.
Safronova VG et al. · 1997
Russian researchers exposed mouse immune cells (neutrophils) to 41.95 GHz millimeter waves at 150 microW/cm2 for 20 minutes to test effects on the cells' ability to produce reactive oxygen species - their primary defense mechanism. The millimeter waves reduced the cells' immune response by up to 60% when calcium levels were high, but only when calcium could enter the cells from outside. This suggests that millimeter wave radiation can interfere with normal immune cell function by disrupting calcium signaling pathways.
Lass L et al. · 2002
Researchers exposed 100 volunteers to low-level 7 Hz-modulated radio frequency radiation (similar to older cell phone frequencies) for 10-20 minutes and tested their attention and memory skills. The exposed group showed increased variability in error rates on two attention tasks, while surprisingly performing better on one memory task. This suggests that even brief, low-level RF exposure can measurably alter cognitive performance in complex ways.
Hinrikus H, Bachmann M, Lass J, Tomson R, Tuulik V. · 2008
Researchers exposed 13 volunteers to 450 MHz microwave radiation while monitoring brain waves. Specific frequencies (14 and 21 Hz) significantly increased brain electrical activity by up to 17%. This proves microwaves can alter normal brain function, with effects varying by frequency.
Hinrikus H, Bachmann M, Lass J, Karai D, Tuulik V. · 2008
Researchers exposed 66 healthy volunteers to low-level microwave radiation at various frequencies and measured their brain activity using EEG. They found that microwave exposure increased brain energy levels, with 13-31% of subjects showing significant changes in their brain wave patterns depending on the frequency used. The study demonstrates that microwave radiation can alter normal brain function even at exposure levels considered safe by current standards.
Bachmann M et al. · 2007
Researchers exposed 14 healthy volunteers to low-level microwave radiation (450 MHz) and measured their brain activity using EEG. They found that the brain initially responded to the radiation by increasing electrical activity, but then adapted by reducing activity below normal levels. This adaptation occurred specifically in alpha and beta brain waves, which are associated with alertness and cognitive function.
Bachmann M et al. · 2006
Estonian researchers exposed healthy volunteers to cell phone-like microwave radiation and measured brain wave activity. They found statistically significant changes in brain electrical patterns in 12% to 30% of subjects, demonstrating that microwave radiation below current safety limits can measurably alter normal brain function.
Bachmann M, Kalda J, Lass J, Tuulik V, Säkki M, Hinrikus H. · 2005
Estonian researchers exposed 23 healthy volunteers to low-level microwave radiation (450 MHz) and measured their brain activity using EEG electrodes. Using advanced analysis techniques, they found that microwave exposure increased brain wave variability in 25% of subjects - changes that traditional analysis methods couldn't detect. This suggests that even weak electromagnetic fields can alter normal brain function patterns.
Rodina A, Lass J, Riipulk J, Bachmann T, Hinrikus H · 2005
Researchers exposed 10 volunteers to low-level microwaves (450 MHz at 0.16 mW/cm²) while testing their ability to recognize and order pairs of face photographs. The study found that microwave exposure caused a statistically significant 5% reduction in visual recognition performance compared to sham exposure. This suggests that even weak electromagnetic fields can subtly affect how the brain processes visual information.
Hinrikus H, Parts M, Lass J, Tuulik V. · 2004
Estonian researchers exposed 20 volunteers to low-level microwave radiation similar to cell phones. The study found measurable changes in brain wave patterns in the frontal region after repeated exposure. Individual responses varied significantly, suggesting some people may be more sensitive to microwave effects than others.
Megha K et al. · 2012
Researchers exposed rats to cell phone frequency radiation (900 MHz) for 2 hours daily over 30 days and found significant cognitive impairment, brain inflammation, and oxidative stress damage. The rats showed worse memory and learning abilities, along with increased inflammatory markers in their brain tissue. This suggests that chronic exposure to microwave radiation at levels similar to cell phones may harm brain function through cellular damage.
Calabrò E et al. · 2012
Italian researchers exposed human brain cells to cell phone radiation at 1800 MHz for 2-4 hours and measured stress protein responses. They found that the radiation triggered cellular stress responses in the neurons, specifically decreasing one protective protein (Hsp20) and increasing another (Hsp70) after longer exposure. This suggests that cell phone radiation can activate stress pathways in brain cells even at levels considered safe by current standards.
Chauhan P, Verma HN, Sisodia R, Kesari KK. · 2017
Researchers exposed rats to 2.45 GHz microwave radiation (the same frequency used in WiFi and microwave ovens) for 2 hours daily over 35 days at very low power levels. The exposed rats showed significant tissue damage and oxidative stress in their brain, liver, kidney, testis, and spleen compared to unexposed control rats. This suggests that even low-level microwave radiation exposure over time may cause cellular damage throughout the body.
Shckorbatov YG et al. · 2002
Researchers exposed human cheek cells to extremely high-frequency microwaves (37.5 and 18.75 GHz) at very low power levels and measured how the cell nuclei responded to electrical fields. They found that microwave exposure changed the electrical properties of cell nuclei and increased cell membrane permeability, with effects varying based on each person's initial cellular characteristics.
Urech, M, Eicher, B, Siegenthaler, J · 1996
Swiss researchers exposed lichens (small organisms that grow on trees and rocks) to microwave radiation at 2.45 GHz for up to three years, using power levels similar to what you'd find near cell towers. They found that high-power microwave exposure (50 mW/cm²) significantly reduced the lichens' growth rate by causing them to heat up and dry out faster than normal.
Kues HA et al. · 1992
Researchers exposed monkeys to 2.45 GHz microwave radiation after applying common eye drops. The medications dramatically increased eye damage sensitivity, lowering the injury threshold from 10 mW/cm² to just 1 mW/cm². People using certain eye medications may face higher risks from everyday microwave exposure.
Cao H, Qin F, Liu X, Wang J, Cao Y, Tong J, Zhao H · 2015
Researchers exposed rats to cell phone radiation (1.8 GHz) for two hours daily over 32 days. The radiation disrupted natural daily rhythms of protective antioxidants in blood, with the largest decreases occurring during nighttime exposure, suggesting interference with the body's 24-hour protective cycles.
Qin F et al. · 2014
Researchers exposed male rats to cell phone radiation (1800 MHz) for 2 hours daily over 32 days and found it disrupted their natural body clocks and harmed reproductive function. The radiation reduced testosterone levels, decreased sperm production and movement, and interfered with the normal daily rhythms that regulate these processes. This suggests that the timing of EMF exposure throughout the day may influence how severely it affects male fertility.
Chen L, Qin F, Chen Y, Sun J, Tong J. · 2014
Researchers exposed male mice to cell phone-level radiation (1800 MHz) for two hours daily over 32 days. The radiation reduced sperm count and testosterone while increasing estradiol and disrupting natural daily hormone rhythms, suggesting potential male fertility risks from cell phone use.
Qin F, Yuan H, Nie J, Cao Y, Tong J. · 2014
Researchers exposed mice to cell phone radiation at 1800 MHz (the frequency used by GSM networks) for either 30 or 120 minutes daily over 30 days. Mice exposed for 120 minutes showed significant learning and memory problems, along with brain chemistry changes indicating oxidative stress. When researchers gave the mice nano-selenium supplements, the cognitive damage was largely prevented.
Qin F, Yuan H, Nie J, Cao Y, Tong J · 2014
Researchers exposed mice to cell phone radiation (1800 MHz) for 30 days and found that 2-hour daily exposures significantly impaired learning and memory performance. The study also tested whether nano-selenium supplements could protect against these cognitive effects, finding that the supplement did help preserve brain function in radiation-exposed mice.
Qin F et al. · 2012
Researchers exposed male rats to cell phone frequency radiation (1800 MHz) for 2 hours daily over 32 days and measured how this affected their natural daily cycles of melatonin and testosterone production. The radiation disrupted both hormones' normal rhythms, with melatonin being more severely affected than testosterone. This suggests that radiofrequency exposure can interfere with the body's internal biological clock that regulates crucial hormones.
Meena R, Kumari K, Kumar J, Rajamani P, Verma HN, Kesari KK. · 2014
Researchers exposed male rats to Wi-Fi frequency radiation (2.45 GHz) for 2 hours daily over 45 days, finding it damaged sperm DNA and caused oxidative stress in testicular tissue. The antioxidant melatonin prevented this damage, suggesting everyday microwave radiation may harm male fertility but antioxidants could provide protection.