Wednesday, February 1, 2023

Wireless Radiation Exposure Limits

Maximum recommended radio frequency exposure levels
(power density) by source

For the general public, the recommended maximum whole-body average radio frequency exposure limit as measured by the incident power density varies by source:

FCC (based on acute heating averaged over 30 minutes)

Recommended levels:

2,000,000 µW/m2 (for 30 - 300 MHz)

frequency (in Hz)/150 µW/m2 (for 300 MHz - 1500 MHz)

10,000,000 µW/m2 (for 1500 MHz - 100,000 MHz)

ICNIRP (2020) (based on acute heating averaged over 30 minutes)

Recommended levels:

2,000,000 µW/m2 (for 30 - 400 MHz)

frequency (in Hz)/200 µW/m2 (for 400 MHz - 2000 MHz)

10,000,000 µW/m2 (for 2000 MHz - 300,000 MHz)


400,000 µW/m2


100,000 µW/m2

Council of Europe, Resolution 1815

Recommended level: 106 µW/m2

European EMF guideline for the prevention, diagnosis and treatment of EMF-related health problems and illnesses.(Belyaev et al,, 2016)

Recommended levels:

FM radio: 100 - 10,000 µW/m2

Cell phone frequencies: 1 - 100 µW/m2

Wi-Fi (2400 and 5000 MHz): 0.1 - 10 µW/m2

BioInitiative Report (2012)

Recommended levels: 3–6 µW/m2

Building Biology Institute guideline for sleeping areas (2015)

Recommended level: <0.1 µW/m2


Mhz = megahertz = million cycles per second

µW/m2 = microwatts per square meter = millionths of a watt per square meter


April 19, 2022

Leading experts on wireless radiation biological effects call for stronger exposure limits in new research review

On April 19, Dr. Henry Lai and B. Blake Levitt published an extensive review of the research on the biological effects of wireless radiation which calls for stronger limits on radio frequency radiation exposure to protect human health. According to their paper, governments should adopt a maximum full-body Specific Absorption Rate (SAR) of 1.65 milliwatts per kilogram which is 48 times lower than the wireless exposure limits that allow the public to be exposed to a full-body SAR of 80 milliwatts per kilogram and 960 times lower than the 1.6 watts per kilogram cell phone exposure limit for the head and torso in the U.S. The paper was published in the peer-reviewed journal, Electromagnetic Biology and Medicine (see abstract and excerpts below).

Dr. Lai is professor emeritus at the University of Washington. In his long research career he has focused on the biological effects of non-ionizing electromagnetic fields and their possible medical applications with research end points covering molecular biology, neurochemistry, behavior, and cancer treatment. He has published over 100 peer-reviewed research papers.

Lai H, Levitt BB. The roles of intensity, exposure duration, and modulation on the biological effects of radiofrequency radiation and exposure guidelines. Electromagn Biol Med. 2022 Apr 3;41(2):230-255. doi: 10.1080/15368378.2022.2065683.


In this paper, we review the literature on three important exposure metrics that are inadequately represented in most major radiofrequency radiation (RFR) exposure guidelines today: intensity, exposure duration, and signal modulation. Exposure intensity produces unpredictable effects as demonstrated by nonlinear effects. This is most likely caused by the biological system’s ability to adjust and compensate but could lead to eventual biomic breakdown after prolonged exposure. A review of 112 low-intensity studies reveals that biological effects of RFR could occur at a median specific absorption rate of 0.0165 W/kg. Intensity and exposure duration interact since the dose of energy absorbed is the product of intensity and time. The result is that RFR behaves like a biological “stressor” capable of affecting numerous living systems. In addition to intensity and duration, man-made RFR is generally modulated to allow information to be encrypted. The effects of modulation on biological functions are not well understood. Four types of modulation outcomes are discussed. In addition, it is invalid to make direct comparisons between thermal energy and radiofrequency electromagnetic energy. Research data indicate that electromagnetic energy is more biologically potent in causing effects than thermal changes. The two likely function through different mechanisms. As such, any current RFR exposure guidelines based on acute continuous-wave exposure are inadequate for health protection.


"Over the last 25–30 years, significant information has been published that in other regulated areas would have resulted in re-examination and adjustments to allowable exposure limits. This has not been the case with these two groups [the FCC and ICNIRP] which adhere to a model based on obsolete scientific evidence, especially in light of the new 5G network that uses higher frequencies and novel modulation forms that have never been used before in broad civilian telecommunications and which are poorly studied."

"RFR effects have been observed at low intensities (< 0.4 W/kg) – a list of which is included in Supplement 1 – far below the guidelines. This points to both the nonlinearity of how living systems couple with nonionizing radiation as well as the inadequacy of acute thresholds. The studies encompass many different biological effects to myriad systems, including: apoptosis induction, adrenal gland activity, blood–brain barrier permeability, brain transmitter levels, calcium concentration in heart muscle, calcium efflux, calcium movement in cells, cell growth, cognitive functions, cellular damage in liver, decreased cell proliferation, embryonic development, endocrine changes, enolose activity, genetic effects, hippocampal neuronal damage, immunological functions, kidney development, memory functions, latency of muscular contraction, membrane chemistry, nerve cell damage, metabolic changes, neural electrical activity, oxidative stress, plant growth, prion level, protein changes, renal injury, serum testosterone concentration, heat-shock protein induction, testis morphology, testosterone synthesis, thymidine incorporation, and ultrastructural alteration in cell cytoplasm. In fact, there are not many physiological functions in humans, animals, or plants that are not affected by low-level RFR."

"As reflected in Supplement 1, SARs at which effects were observed were available from 112 studies. Of these, 75 (67%) were in vivo exposure studies with whole body/organ SARs available. The other 37 (33%) studies were in vitro experiments.... The level at which biological effects occur represents data from in vivo and in vitro and acute and chronic/repeated-exposure experiments. There is a very wide range of effects seen. With an exposure that induces a SAR of 0.0165 W/kg, and using a ten-fold protection, the SAR would be 0.00165 W/kg (i.e., 1.65 mW/kg). For rate of energy absorption in body organs, 0.00165 W/kg is far below the maximum level allowed in the guidelines (whether over 1 or 10 gm of tissue as per FCC/ICNIRP allowances). Given the large body of work as illustrated in Supplement 1, the SAR at, or below, 4 W/kg as a safe threshold is insupportable."

"The duration of exposure is another important factor in biological effects. Other than demarcations for whole body exposures averaged over 30 minutes and local body areas averaged over 6 minutes, neither FCC nor ICNIRP address duration, especially pertaining to long-term and low-level RFR exposures. These are prevalent in both near-field exposures to people with WiFi routers, for example, as well as cell phones, and far-field exposures from infrastructure that have created chronic rising ambient background levels (Levitt et al. 2021a). The guidelines are written only for short-term acute durations.... What we do know is that the supposition that all exposures are the same above and below the SAR threshold set by FCC/ICNIRP is fundamentally flawed in light of the most current research. One feasible and logical solution to such uncertainties regarding duration as an exposure factor would be to adopt an SAR level commensurate with the studies summarized in Supplement 1 at no higher than 0.00165 W/kg, no matter the exposure conditions."

"It is generally believed that modulated RFR is more biologically active than continuous-wave (CW) radiation, i.e., the carrier-wave. To understand the biological and possible hazardous health effects of RFR, it is therefore important to understand modulation effects. Below we discuss what is known about modulation from the research literature (mostly from 1990 to date) and examine the claim that modulation makes RFR more biologically significant...There is research showing no significant biological effects of CW-RFR (Table 1a) but there are also studies that reported CW-RFR effects too (Table 1b). The reason why CW-RFR produced effects in some studies but not others is unknown. Both types of studies (with “effect” and “no effect” outcomes) involved many different biological endpoints, exposure intensities, and duration of exposure – with no discernible differences. A possible explanation is that different tissue types respond differently to CW-RFR. But that just adds another level of inquiry. One of the most puzzling observations is when CW caused an effect but modulation did not (e.g., Kubinyi et al. 1996; Luukkonen et al. 2009). In some studies, a modulated field produced an effect that was not produced by CW. These observations may indicate that the CW carrier-wave itself and modulation act on different mechanisms.... Differences in responses between CW and modulated fields of the same frequency and incident power density provide strong proof that non-thermal effects occur since the two conditions should produce the same amount of heating.... Some studies reported that different frequencies of modulation caused different biological responses .... CW and modulated fields can cause the same effects but with different degrees of biological activity and intensity of reactions. In most instances, a modulated field was found to be more potent than CW versus only one study in which the opposite was reported (Persson et al. 1997).... To add to the complexities described above, effects with modulated fields have also been shown to depend on exposure duration.... there are many studies that used intermittent exposure (e.g., 10 min ON/10 min OFF) instead of continuous exposure with the supposition that intermittent exposure is more biologically active. But not much data showed this to be true.... There are many studies using pulsed fields (i.e., mobile phone signals are pulsed), but there are not many studies that compared pulsed and CW fields of the same SAR in the same study. However, there are reports that effects only occurred with a pulsed field but not CW.... there are many studies showing effects of RFR on the hippocampus..."

"Oxidative changes and stress have been reported in many papers on exposure to electromagnetic fields (Lai 2020; Yakymenko et al. 2016). These are the most consistent cellular responses to RFR exposure. Mechanisms have been proposed to account for oxidative effects that may involve the low-frequency component of modulation (e.g., see Barnes and Greenebaum 2015; Castello et al. 2021). ... But there is not enough data to conclude that modulation effects are caused by oxidative processes. In fact some effects of CW exposure alone also found changes in free radical mechanisms."

"It is important to point out as significant proof of non-thermal RFR effects that CW and modulated-waves of the same frequency and incident power density can/and do produce different effects. The bottom line is that certainty is elusive regarding precise effects in all circumstances. What is clear is that both modulation and continuous-wave RFR are biologically active and both should be considered in exposure guidelines. In situations where enough evidence exists to warrant specific caution, such as with pulsed fields used in cell phones and phased modulation with 5G, particular attention should be paid to include modulation in the guidelines beyond the suppositions of safety contained within the safety allowances. Peak exposures must also be factored in and not just the averaged values which only hide their significance."

"It is apparent that the biological outcome of changing the intensity and duration of RFR exposure is basically unpredictable. This is mainly due to the complex nature of the biological system studied. Intensity and duration can interact and produce different response patterns as shown in the literature reviewed above.

It is also apparent that how RFR modulation affects biological functions is difficult to quantify. Observed effects are multi-variant and involve many factors such as intensity, carrier frequencies and modulation, the modulation waveform itself, exposure duration, and properties of the exposed object. Not enough research data are presently available to provide an explanation or prediction of modulation effects under all circumstances. It may also turn out that modulation is of little major health concern or conversely that it is the only factor that matters – evidence is thus far too contradictory regarding modulation’s ability to consistently enhance the biological effects of carrier-waves. Then again, with most modulation forms the carrier-wave is completely altered. All of this awaits proper investigation with comparison studies. In the meantime, there are legitimate reasons for concern, given the contradictions in the literature.

In general, anthropogenic RFR – with highly unusual waveform characteristics and intensities that do not exist in the natural world – is new to the environment and thus has not been a factor in the evolution of species. Living organisms evolved over millions of years in the presence of static and extremely-low frequency (ELF) electromagnetic fields. These fields play critical roles in their survival, e.g., in migration, food foraging, and reproduction, etc. (see Levitt et al. 2021b). Living organisms are extremely sensitive to the presence of these environmental fields and thus, they can easily be disturbed by man-made EMF. RFR probably acts upon and modifies these primordial EMFs and affects biological functions. Interactions of static/ELF EMF and RFR are basically not well studied, not to mention the mechanisms of involvement of RFR modulations. The interactions are inevitably complex. Such interaction studies would provide answers to wildlife effects.

Regarding the perennial thermal- versus non-thermal- effects criticism inherent in human RFR exposure guidelines, it must be said that the underlying mechanisms of effects should not be a matter of concern in setting of exposure guidelines as is common today. What is important is the level at which energy absorption causes an effect. One such powerful proof – among so very many others – of non-thermal effects is evidenced in the fact that CW and modulated-waves of the same frequency and incident power density can produce different effects, as seen in the modulation section of this paper and Table 2."

"When effects continue to be observed over a long period of time that go against prevailing beliefs, even when mechanisms remain imperfectly understood, the appropriate course of regulatory action is to examine the underlying basis upon which an original premise was formed. When proven incomplete or invalid by new information, the change in a regulatory course is not only justified but is imperative. Disproven or incomplete deductions of how RFR affects living cells and tissues, as well as suppositions of safety for exposed individuals and the environment are insupportable given the wealth of studies to draw from today that have filled in many gaps. We need to more responsibly address the increasing near- and far-field RFR exposures of contemporary life with an eye toward 5G technology’s unique characteristics. A new conceptual framework is called for."


Study: Wireless radiation exposure for children should be hundreds of times lower than current federal limits

Environmental Working Group, July 2021

WASHINGTON – A peer-reviewed study by the Environmental Working Group recommends stringent health-based exposure standards for both children and adults for radiofrequency radiation emitted from wireless devices. EWG’s children’s guideline is the first of its kind and fills a gap left by federal regulators.

The study, published in the journal Environmental Health, relies on the methodology developed by the Environmental Protection Agency to assess human health risks arising from toxic chemical exposures. EWG scientists have applied the same methods to radiofrequency radiation from wireless devices, including cellphones and tablets.

EWG recommends the Federal Communications Commission, or FCC, adjust its woefully outdated health standards for wireless radiation, last revised a quarter-century ago, well before wireless devices became ubiquitous, heavily used appliances synonymous with modern life. The recommendation draws on data from a landmark 2018 study from the National Toxicology Program, or NTP, one of the largest long-term studies on the health effects of radiofrequency radiation exposure.

EWG’s new guidelines, the first developed in the U.S. to focus on children’s health, recommend that children’s exposure overall be 200 to 400 lower than the whole-body exposure limit set by the FCC in 1996.

The EWG recommended limit for so-called whole-body Specific Absorption Rate, or SAR, for children is 0.2 to 0.4 milliwatts per kilogram, or mW/kg. For adults, EWG recommends a whole-body SAR limit of 2 to 4 mW/kg, which is 20 to 40 times lower than the federal limit.

The FCC has not set a separate standard for children. Its standards for radiofrequency radiation set a maximum SAR of 0.08 watts per kilogram, or W/kg, for whole-body exposure and an SAR for localized spatial peak – the highest exposure level for a specific part of the body, such as the brain – of 1.6 W/kg for the general population.

The NTP studies examined the health effects of 2G and 3G wireless radiation and found there is “clear evidence” of a link between exposure to radiofrequency radiation and heart tumors in laboratory animals. Similar results were reported by a team of Italian scientists from the Ramazzini Institute.

Cellphone radiation was classified a “possible carcinogen” in 2011 by the International Agency for Research on Cancer, part of the World Health Organization, a conclusion based on human epidemiological studies that found an increased risk of glioma, a malignant brain cancer, associated with cellphone use.

EWG scientists say that more research is needed on the health impacts of the latest generation of communication technologies, such as 5G. In the meantime, EWG’s recommendation for strict, lower exposure limits for all radiofrequency sources, especially for children.

When the FCC established its radiofrequency radiation limits, following the passage of the 1996 Telecommunications Act, relatively few Americans, and likely no children, owned and used cellphones.

Much has changed since the federal limits were set, including technology and how these devices are used. A survey completed by the nonprofit Common Sense Media in March 2020, just before the start of the Covid-19 spread in the U.S., found that 46 percent of 2- to 4-year-olds, and 67 percent of 5- to 8-year-olds, had their own mobile devices, such as a tablet or smartphone.

With remote learning, a necessity during the Covid-19 pandemic, phones, tablets and other wireless devices became a part of life for young children, tweens and teens nationwide.

“The FCC must consider the latest scientific research, which shows that radiation from these devices can affect health, especially for children,” said Uloma Uche, Ph.D., EWG environmental health science fellow and lead author of the study.

“It has been 25 years since the FCC set its limits for radiofrequency radiation. With multiple sources of radiofrequency radiation in the everyday environment, including Wi-Fi, wireless devices and cell towers, protecting children’s health from wireless radiation exposures should be a priority for the FCC,” she added.

“We have grave concerns over the outdated approach the federal government has relied on to study the health effects of cellphone radiation and set its current safety limit and advice for consumers,” said EWG President Ken Cook. “Government guidelines are a quarter-century old and were established at a time when wireless devices were not a constant feature of the lives of nearly every American, including children.”

Reviewing 5G and other aspects of wireless technology should be the focus of public health agencies, noted Cook. “It is long past time the federal government made exposure to 5G wireless devices safe. We strongly believe those exposures deserve far more investigation and scientific rigor than has been applied to date.”

“The evidence shows that children absorb more radiofrequency radiation than adults, and the developing body of a child is more vulnerable to such effects,” said Olga Naidenko, Ph.D., EWG’s vice president for science investigations and co-author of the study.

“More research on the safety and sustainability of wireless technology is essential,” added Naidenko. “Meanwhile, there are simple steps everyone can take to protect their health, such as keeping wireless devices farther from their bodies.”

There are a number of easy, precautionary steps consumers can take until the government conducts the rigorous scientific assessment the issue deserves, which should have occurred years ago.

“Based on our review of the health risks and the inadequacy of current standards to protect children, while the science evolves, it is perfectly reasonable for parents to consider minimizing or eliminating radiofrequency radiation sources at home by relying more on wired internet access, and to urge schools to take comparable steps to reduce classroom and campus exposure,” said Cook.

Other health-protective tips for consumers who want to reduce radiofrequency radiation from wireless devices include using a headset or speaker, texting instead of talking, and limiting the time children spend on smart phones.

Find all of EWG’s tips to reduce exposure to wireless radiation here.

EWG’s recommendation for limits for radiofrequency radiation exposure is its latest effort to advance the public dialogue about science-based standards that protect public health.

Development of health-based exposure limits for radiofrequency radiation from wireless devices using a benchmark dose approach

Uche UI, Naidenko OV. Development of health-based exposure limits for radiofrequency radiation from wireless devices using a benchmark dose approach. Environ Health. 2021 Jul 17;20(1):84. doi: 10.1186/s12940-021-00768-1.


Background  Epidemiological studies and research on laboratory animals link radiofrequency radiation (RFR) with impacts on the heart, brain, and other organs. Data from the large-scale animal studies conducted by the U.S. National Toxicology Program (NTP) and the Ramazzini Institute support the need for updated health-based guidelines for general population RFR exposure.

Objectives  The development of RFR exposure limits expressed in whole-body Specific Absorption Rate (SAR), a metric of RFR energy absorbed by biological tissues.

Methods  Using frequentist and Bayesian averaging modeling of non-neoplastic lesion incidence data from the NTP study, we calculated the benchmark doses (BMD) that elicited a 10% response above background (BMD10) and the lower confidence limits on the BMD at 10% extra risk (BMDL10). Incidence data for individual neoplasms and combined tumor incidence were modeled for 5% and 10% response above background.

Results  Cardiomyopathy and increased risk of neoplasms in male rats were the most sensitive health outcomes following RFR exposures at 900 MHz frequency with Code Division Multiple Access (CDMA) and Global System for Mobile Communications (GSM) modulations. BMDL10 for all sites cardiomyopathy in male rats following 19 weeks of exposure, calculated with Bayesian model averaging, corresponded to 0.27–0.42 W/kg whole-body SAR for CDMA and 0.20–0.29 W/kg for GSM modulation. BMDL10 for right ventricle cardiomyopathy in female rats following 2 years of exposure corresponded to 2.7–5.16 W/kg whole-body SAR for CDMA and 1.91–2.18 W/kg for GSM modulation. For multi-site tumor modeling using the multistage cancer model with a 5% extra risk, BMDL5 in male rats corresponded to 0.31 W/kg for CDMA and 0.21 W/kg for GSM modulation.

Conclusion  BMDL10 range of 0.2—0.4 W/kg for all sites cardiomyopathy in male rats was selected as a point of departure. Applying two ten-fold safety factors for interspecies and intraspecies variability, we derived a whole-body SAR limit of 2 to 4 mW/kg, an exposure level that is 20–40-fold lower than the legally permissible level of 0.08 W/kg for whole-body SAR under the current U.S. regulations. Use of an additional ten-fold children’s health safety factor points to a whole-body SAR limit of 0.2–0.4 mW/kg for young children.


Related Posts:  

Study: Wireless radiation exposure for children should be hundreds of times lower than federal limits (based on NTP study)

ICNIRP’s Exposure Guidelines for Radio Frequency Fields 

Worldwide Radio Frequency Radiation Exposure Limits versus Health Effects