Scientific & policy developments regarding the biological & health effects of electromagnetic radiation from cell phones, cell towers, Wi-Fi, Smart Meters, electric vehicles & other wireless technology, including 5G. Website curated by Joel Moskowitz, PhD, Director, Center for Family & Community Health, UC Berkeley School of Public Health.
A scoping review and evidence map of radiofrequency field exposure and
genotoxicity: assessing in vivo, in vitro, and epidemiological data
Weller
SG, McCredden JE, Leach V, Chu C, Lam AK-Y (2025) A scoping review and
evidence map of radiofrequency field exposure and genotoxicity:
assessing in vivo, in vitro, and epidemiological data. Front. Public
Health 13:1613353. doi: 10.3389/fpubh.2025.1613353.
Abstract
Background
Studies investigating genotoxic effects of radiofrequency
electromagnetic field (RF-EMF) exposure (3 kHz−300 GHz) have used a wide
variety of parameters, and results have been inconsistent. A systematic
mapping of existing research is necessary to identify emerging patterns
and to inform future research and policy.
Methods
Evidence mapping was conducted using guidance from the Preferred
Reporting Items for Systematic reviews and Meta-Analyses for Scoping
Reviews (PRISMA-ScR). A comprehensive search strategy was applied across
multiple research databases, using specific inclusion and exclusion
criteria within each knowledge domain. Quantitative aggregation using
tables, graphs and heat maps was used to synthesize data according to
study type, organism type, exposure level and duration, biological
markers (genotoxicity, cellular stress, apoptosis), RF-EMF signal
characteristics, as well as funding source to further contextualize the
evidence landscape. Quality criteria were applied as part of a focused
analysis to explore potential biases and their effects on outcomes.
Results
Over 500 pertinent studies were identified, categorized as in vitro
(53%), in vivo (37%), and epidemiological (10%), and grouped according
to type of DNA damage, organism, intensity, duration, signal
characteristics, biological markers and funding source. In vitro studies
predominantly showed proportionally fewer significant effects, while in
vivo and epidemiological studies showed more. DNA base damage studies
showed the highest proportion of effects, as did studies using GSM
talk-mode, pulsed signals and real-world devices. A complex relationship
was identified between exposure intensity and duration, with duration
emerging as a critical determinant of outcomes. A complex U-shaped
dose-response relationship was evident, suggesting adaptive cellular
responses, with increased free radical production as a plausible
mechanism. Higher-quality studies showed fewer significant effects;
however, the funding source had a stronger influence on outcomes than
study quality. Over half (58%) of studies observing DNA damage used
exposures below the International Commission of Non-Ionizing Radiation
Protection (ICNIRP) limits.
Conclusion
The collective evidence reveals that RF-EMF exposures may be genotoxic
and could pose a cancer risk. Exposure duration and real-world signals
are the most important factors influencing genotoxicity, warranting
further focused research. To address potential genotoxic risks, these
findings support the adoption of precautionary measures alongside
existing thermal-based exposure guidelines.
Excerpts
Implications for policy and practice
The evidence from the evidence map indicates that medium to long-term RF-EMF exposures, particularly at low intensities, can induce genetic damage through non-thermal mechanisms such as increased free radical production and oxidative stress. Genetic damage can have far-reaching, long-term, and potentially irreversible consequences for individual organisms and broader ecological and planetary health (112, 113).
Both In vivo and epidemiological RF-EMF studies provide credible evidence of genotoxicity, suggesting potential risks such as increased cancer susceptibility and reproductive harm. Studies on brain cells frequently reported positive findings for DNA damage, suggesting that brain cells may be particularly sensitive to RF-EMF, indicating a risk for neurological diseases and brain tumors, as observed in animal models (114–116).
Current RF-EMF exposure guidelines established by ICNIRP (15), prioritize the prevention of thermal effects by incorporating substantial safety margins (e.g., a 50-fold reduction from effect thresholds, setting a local SAR limit of 2 W/kg for the head and torso for the general public, averaged over 10 grams of tissue). However, the evidence mapping process found statistically significant DNA damage at extremely low intensities, with the lowest recorded effects occurring at a SAR of 0.000000319 W/kg in an epidemiological study (117) and at 0.000003 W/kg in several in vivo experiments (118, 119). These levels are substantially (>600,000 times) below the ICNIRP public exposure limits (15). This pattern suggests non-thermal genotoxic effects, because temperature changes at these intensities would be negligible and not measurable.
ICNIRP (2020) guidelines (15) set RF-EMF exposure limits to protect against thermal effects from acute exposures, with averaging times of 6 min for local exposure (head and torso) and 30 min for whole-body exposure. However, the above analysis revealed that medium (1 day−3 months) and long-term RF-EMF exposures (>3 months or 1,000 h) were most strongly linked to genotoxic effects, even at very low exposure intensities. ICNIRP (2020) guidelines (15) do not set specific limits for chronic, low-level RF-EMF exposures, particularly for non-thermal effects like genotoxicity, citing “no substantiated evidence of health-relevant effects” [(15), p. 522].
The mapping process also revealed that RF exposures are associated with genetic damage in a wide range of organisms, with an observed sensitivity of non-mammalian organisms, such as plants, insects, and possibly amphibians. Current guidelines neglect potential effects on wildlife or ecosystems (78, 96). Notably, a recent WHO-commissioned systematic review of animal studies suggested carcinogenic effects from RF-EMF exposures (116). Other studies suggest biological effects on non-human species (120, 121). Together, these results suggest that the environmental implications of RF-EMF exposure merit greater scrutiny (122), even though the current evidence remains limited and debated (96).
While these findings do not yet establish causation or a clear No Observed Adverse Effect Level (NOAEL), they indicate risks that ICNIRP's current framework discounts by prioritizing only effects with confirmed harm [(15), p. 487]. ICNIRP's review process and position is best described as a hazard-based assessment focused only on confirmed effects. This approach is overly restrictive, as it delays updating guidelines until absolute certainty is achieved (123), which may not align with the precautionary needs of public health or environmental protection.
Currently, there is a widespread (6) and often non-consensual nature to RF-EMF exposure (92) from mobile phones, base stations, and other wireless technologies. While acknowledging the permanence of this technology in modern society, policy adjustments are required that prioritize health and environmental protection over economic interests. This can be achieved by adopting a precautionary approach to RF-EMF (123) and addressing potential risks from non-thermal RF-EMF effects, despite scientific uncertainty. Strategies such as justification (assessing net benefits of RF-EMF applications), optimization (balancing protection with societal needs), and As low as Reasonably Achievable or As Low as Technically Achievable - ALARA/ALATA (avoiding deterministic effects and minimizing stochastic effects) per International Commission on Radiological Protection (ICRP) recommendations - ICRP103 (124) could be considered. Further development and deployment of wireless technologies should incorporate improved safety measures in their design (125), such as creating devices that emit lower levels of RF-EMF or using materials and antenna designs to direct emissions away from the body.
Additionally, public information regarding potential health risks and personal protective measures could be disseminated through public health campaigns, making use of existing advice such as the EUROPAEM EMF Guideline 2016 (126); e.g. minimizing the use of wireless devices, prioritizing wired connections, maintaining distance between RF-EMF sources and the body, use of air-tube headsets or handsfree calls, turning off wireless when not in use, and mitigation of oxidative stress by incorporating antioxidants into the diet.
While individual actions are valuable, they are not a substitute for robust regulatory standards and industry accountability. Ensuring the safety of wireless technologies requires a collective effort from manufacturers, policymakers, and consumers to develop comprehensive RF safety guidelines. Future regulatory guidelines could encompass workplace protection measures, including substitution, engineering, and administrative controls (127), integration of building biology standards (128), mandatory detailed product labeling to inform users of potential risks, and standardized safety hygiene practices.
Recommended actions
To address these concerns and bridge existing gaps, the following actions are recommended:
Standardization of Research Protocols: Harmonizing
methodologies across studies, particularly comet assay protocols, is
critical for reducing heterogeneity and enabling robust meta-analyses.
Focus on Long-Term and Low-Intensity Exposures:
Future research should prioritize investigating the cumulative effects
of prolonged and low-intensity RF-EMF exposures, which are most relevant
to real-world scenarios and devices.
Inclusion of Emerging Frequencies: Given the rapid
deployment of 5G and other novel technologies, research focused on
higher frequencies and new modulation schemes is urgently needed.
Targeted Environmental and Health Studies: Targeted
research in both human health and ecological systems needs to be
conducted independently of vested interest influences, ensuring
methodological rigor in each domain.
Independent Funding and Research Oversight: To
mitigate biases associated with industry funding, greater support for
independent research is essential. Transparent disclosure of ALL funding
sources and researcher affiliations should be mandatory.
Re-evaluation of RF Standards: Regulatory bodies must
update exposure guidelines to reflect non-thermal mechanisms and the
potential health effects from long-term chronic exposure settings by
incorporating findings from independent, high-quality studies.
Conclusions
The evidence map presented here reveals statistically
significant DNA damage in humans and animals resulting from man-made
RF-EMF exposures, particularly DNA base damage and DNA strand breaks.
The evidence also suggests plausible mechanistic pathways for DNA
damage, most notably through increased free radical production and
oxidative stress. Sensitivity to damage varied by cell type, with
reproductive cells (testicular, sperm and ovarian) along with brain
cells appearing particularly vulnerable. A complex U-shaped
dose-response relationship was observed for both exposure duration and
intensity, with more DNA damage occurring in specific frequency and
intensity combination windows. DNA damage was more likely to be found
using in vivo studies, very weak or very strong signal
intensities, very short or very long exposure durations, 900, 1,800 and
2,450 MHz frequencies, GSM-talk mode and pulsed modulations,
particularly when using real-world devices. On the other hand, research
funded by vested interests has tended to use different experimental
design parameters, with a high proportion of studies using in vitro,
short-term exposures, medium-high intensity signals and using signal
generators. Funding source is also a stronger determinant of
experimental outcomes than study quality.
Overall, there is a strong evidence base showing DNA damage and
potential biological mechanisms operating at intensity levels much
lower than the ICNIRP recommended exposure limits. Public policy could
benefit from the implementation of precautionary measures such as ALARA
or ALATA, along with public information campaigns to better safeguard
human and environmental health and wellbeing.
Genetic effects of non-ionizing electromagnetic fields
Lai H. Genetic effects of non-ionizing electromagnetic fields.
Electromagn Biol Med. 2021 Apr 3;40(2):264-273. doi:
10.1080/15368378.2021.1881866.
Abstract
This is a review of the research on the
genetic effects of non-ionizing electromagnetic field (EMF), mainly on
radiofrequency radiation (RFR) and static and extremely low frequency
EMF (ELF-EMF). The majority of the studies are on genotoxicity (e.g.,
DNA damage, chromatin conformation changes, etc.) and gene expression.
Genetic effects of EMF depend on various factors, including field
parameters and characteristics (frequency, intensity, wave-shape), cell
type, and exposure duration. The types of gene expression affected
(e.g., genes involved in cell cycle arrest, apoptosis and stress
responses, heat-shock proteins) are consistent with the findings that
EMF causes genetic damages. Many studies reported effects in cells and
animals after exposure to EMF at intensities similar to those in the
public and occupational environments. The mechanisms by which effects
are induced by EMF are basically unknown. Involvement of free radicals
is a likely possibility. EMF also interacts synergistically with
different entities on genetic functions. Interactions, particularly with
chemotherapeutic compounds, raise the possibility of using EMF as an
adjuvant for cancer treatment to increase the efficacy and decrease side
effects of traditional chemotherapeutic drugs. Other data, such as
adaptive effects and mitotic spindle aberrations after EMF exposure,
further support the notion that EMF causes genetic effects in living
organisms.
Excerpts
"Supplements
1 and 2 show that the majority of studies reported genetic effects of
EMF (66% for RFR and 79% for static/ELF-EMF). Thus, it is safe to
conclude that genotoxic effects of EMF have been reported. The most
common effects found are: DNA strand breaks, micronucleus formation, and
chromosomal structural changes. There are not many studies on mutation.
Thus, it is not known whether these genotoxic effects transform into
mutation and involved in carcinogenesis. Interestingly, available data
do not suggest mutagenic effect after RFR exposure (Chang et al., 2005;
Meltz et al., 1990; Ono et al., 2004; Takahashi et al., 2002); whereas
most static/ELF-EMF studies (Chahal et al., 1993; Mairs et al., 2007;
Miyakoshi, 1997; Miyakoshi et al., 1998, 1996; Potenza et al., 2004;
Wilson et al., 2015) suggested some mutagenic effects...."
"There are similarly many studies that showed changes in gene expression
after EMF exposure (Supplement 3). Changes in expression of many
different genes have been reported. Studies in gene expression by
static/ELF-EMF are far more diversified than those of RFR. The most
interesting results are the expression of genes related to stress
response both in vitro and in vivo in plans and animals. Another
important finding is the expression of heat shock proteins, particularly
HSP70, which is an important protein involved in protein misfolding and protecting cells from environmental stress...."
"Effects
of EMF on cellular free radical processes have been reported in many
experiments (cf. Lai, 2019; Yakymenko et al., 2016). It is conceivable
that an increase in free radicals in cells could cause macromolecular
damages including DNA. There are many reports on involvements of free
radicals in genetic processes, including both reactive oxygen species
and reactive nitrogen species...."
"There are many reports of genetic effects induced by low intensities of
EMF. The studies are listed in Supplement 4. This is an important topic
to consider since living organisms are being constantly exposed to low
levels of EMF in the occupational and public environments. This is
particularly true for ELF-EMF, since intensities of ELF-EMF in the
environment are in microtesla (µT) levels, even exposure to fields from
electrical appliances rarely exceed 10 microtesla (i.e., 0.01 mT).
However, most laboratory cell and animal studies in ELF-EMF used fields
in the millitesla (mT) level...."
"Another important observation of the studies is that EMF can interact
with other entities and synergistically cause genetic effects....
Most of the compounds that have been shown to interact with EMF are
mutagens. This is important because in real-life situations, a person is
usually exposed simultaneously to EMF and many different environmental
factors, including mutagens.
"
"Two other important findings of recent studies are that the effects of
EMF are waveform specific and cell-type specific (Supplement 5). These
findings underscore the complicity of interaction of EMF with biological
tissues and may partially explain why effects were observed in some
studies and not others. It is essential to understand why and how
certain wave-characteristics of an EMF are more effective than other
characteristics in causing biological effects, and why certain types of
cells are more susceptible to the effect of EMF? The fact that “there
are different biological effects elicited by different EMF
wave-characteristics” is a critical proof for the existence of
non-thermal effects...."
"Regarding cell-type specificity, one can speculate that: 1. Cells that
are metabolic active are more susceptible to EMF effects with an
increase in generation of free radical in the mitochondria; 2. Cells
that have higher anti-oxidative activities are less susceptible; 3.
Transitional elements, e.g., iron, may play a role in the effect via the
Fenton reaction (see Lai, 2019).
Brain cells contain a relatively high concentration of free iron,
particularly intercalated in the DNA molecules, and are more
susceptible; 4. Cell cycle arrests are common in cells exposed to EMF.
It may be a response to repair genetic damages caused by EMF. If damage
could not be repaired, cell death occurs, particularly via apoptosis,
which is a common outcome after EMF exposure. These effects are
consistent with the gene expression studies, showing activation of genes
involved in both cell death and repair. 5. If genetic damaged cells are
allowed to survive, cancer may occur. However, if they die, the risk of
cancer would actually be reduced. But, other detrimental health
outcomes may occur, e.g., death of brain cells could lead to
neurodegenerative diseases. Increased incidences of degenerative
diseases..."
"The main question is whether EMF
exposure could cause genetic effects? It is pertinent here to quote a
recent statement made by two prominent bioelectromagnetic researchers
(Barnes and Greenebaum, 2020): “The evidence that weak radiofrequency
(RF) and low-frequency fields can modify human health is still less
strong, but the experiments supporting both conclusions are too numerous
to be uniformly written off as a group due to poor technique, poor
dosimetry, or lack of blinding in some cases, or other good laboratory
practices.” All in all, in the studies reviewed in Supplements 1 and 2,
approximately 70% of them showed effects. One could say that EMF
exposure can lead to genetic changes. Some genetic damages could
eventually lead to detrimental health effects. However, the mechanisms
remain to be uncovered. But, knowing the mechanism is not necessary to
accept that the data are valid. It is also a general criticism that most
EMF studies cannot be replicated. I think it is a conceptual and
factual mis-statement. Replication is also not a necessary and
sufficient condition to believe that certain data are true. Scientific
studies are hardly replicated. Rational funders do not generally fund
replications. All scientists should know that it is very difficult to
replicate exactly an experiment carried out by another lab. This is
particularly true when the effects of EMF depend on many unknown
factors. By the way, not many replication experiments have been carried
out in EMF genetic-effect research to justify the statement that “data
from EMF are not replicable”. In some cases, the experimenters
deliberately changed the procedures of an experiment that they were
supposed to be replicating and claimed that their experiment was a
replication, for example, compare the experimental procedures of Lai and
Singh (1995) and Malyapa et al. (1998).
To prove an
effect, one should look for consistency in data. Genetic damage studies
have shown similar effects with different set-up and in various
biological systems. And, the gene expression results (Supplement 3) also
support the studies on genetic damages. Expression of genes related to
cell differentiation and growth, apoptosis, free radical activity, DNA
repair, and heat-shock proteins have been reported. These changes could
be consequences of EMF-induced genetic damages.... In conclusion, there
are enough reasons to believe that genetic effects of EMF are real and
possible.
During cell phone use, a relatively constant mass of
tissue in the brain is exposed to the radiation at relatively high
intensity (peak specific absorption rate (SAR) of 4–8 W/kg). Many papers
have reported genetic effect/DNA damage at much lower SAR (or power
density) (see Supplement 4). This questions the wisdom of the several
exposure standard-setting organizations in using the obsolete data of 4
W/kg (whole-body averaged SAR) as the threshold for exposure-standard
setting. Furthermore, since critical genetic mutations in one single
cell are sufficient to lead to cancer and there are millions of cells in
a gram of tissue, it is inconceivable that some standards have changed
the SAR from averaged over 1 gm to 10 gm of tissue. (The limit of
localized tissue exposure has been changed from 1.6 W/kg averaged over 1
gm of tissue to 2 W/kg over 10 gm of tissue. Since distribution of
radiofrequency energy is non-homogenous inside tissues, this change
allows a higher peak level of exposure.) What is actually needed is a
better refinement of SAR calculation to identify ‘peak values’ of SAR
inside the brain.
Any effect of EMF has to depend on the energy
absorbed by a biological entity and on how the energy is delivered in
space and time. Aside from influences that are not directly related to
experimentation (Huss et al., 2007), many factors could influence the
outcome of an experiment in bioelectromagnetics research. Frequency,
intensity, exposure duration, and the number of exposure episodes can
affect the response, and these factors can interact with each other to
produce different effects. In addition, in order to understand the
biological consequences of EMF exposure, one must know whether the
effect is cumulative, whether compensatory responses result, and when
homeostasis will break down. A drawback in the interpretation and
understanding of experimental data from bioelectromagnetic research is
that there is no general accepted mechanism on how EMF affects
biological systems. Since the energy level is not sufficient to cause
direct breakage of chemical bonds within molecules, the effects are
probably indirect and secondary to other induced chemical changes in the
cell. The mechanisms by which EMF causes genetic effects are unknown.
This author suspects that biological effects of EMF exposure are caused
by multiple inter-dependent biological mechanisms."
Hybrid and electric cars may be cancer-causing as they emit extremely low frequency (ELF) electromagnetic fields (EMF). Recent studies of the EMF emitted by these automobiles have claimed either that they pose a cancer risk for the
vehicles' occupants or that they are safe.
Unfortunately, much of the research conducted on this issue has been industry-funded by companies with vested interests on one side of the issue or the other which
makes it difficult to know which studies are trustworthy.
Meanwhile, numerous peer-reviewed laboratory studies conducted over several decades have found biologic effects from limited exposures to ELF EMF. These studies suggest that the EMF guidelines established by the self-appointed, International Commission on Non-Ionizing Radiation Protection(ICNIRP) are inadequate to protect our
health. Based upon the research, more than 250 EMF experts have signed the International EMF Scientist Appeal which calls on the World Health Organization to establish stronger guidelines for ELF and radio frequency EMF. Thus, even if EMF measurements comply with the ICNIRP guidelines, occupants of hybrid and electric cars may still be at increased risk for cancer and other health problems. Given that magnetic
fields have been considered "possibly carcinogenic" in humans by the
International Agency for Research on Cancer of the World Health Organization since
2001, the precautionary principle dictates that we should design consumer
products to minimize consumers’ exposure to ELF EMF. This especially applies to hybrid and electric automobiles as drivers and passengers spend considerable amounts of time in these vehicles, and health risks increase with the duration of exposure.
In January 2014, SINTEF, the largest independent research organization in Scandinavia,
proposed manufacturing design guidelines that could reduce the magnetic fields in electric vehicles (see
below). All automobile manufacturers should follow these guidelines to ensure their customers' safety.
The public should demand that governments adequately fund high-quality
research on the health effects of
electromagnetic fields that is independent of industry to eliminate any potential conflicts of interest. In the U.S., a
major national research and education initiative could be funded with as little as a 5
cents a month fee on mobile phone subscribers.
Following are summaries and links to recent studies and news articles on this topic. --
Magnetic Field Measurement of Various Types of Vehicles, Including Electric Vehicles
My note: The
"reference levels" recommended by the International Commission on
Non-Ionizing Radiation Protection (ICNIRP) for public exposure are no
assurance of safety.
Fukui H,
Minami N, Tanezaki M,
Muroya S, Ohkubo C.
Magnetic Field Measurement of Various Types of Vehicles,
Including Electric Vehicles. Electronics. 2025; 14(15):2936.
https://doi.org/10.3390/electronics14152936
Abstract
Since around the year 2000, following
the introduction of electric vehicles (EVs) to the market, some people
have expressed concerns about the level of magnetic flux density (MFD)
inside vehicles. In 2013, we reported the results of MFD measurements
for electric vehicles (EVs), hybrid electric vehicles (HEVs), and
internal combustion engine vehicles (ICEVs). However, those 2013
measurements were conducted using a chassis dynamometer, and no
measurements were taken during actual driving. In recent years, with the
rapid global spread of EVs and plug-in hybrid electric vehicles
(PHEVs), the international standard IEC 62764-1:2022, which defines
methods for measuring magnetic fields (MF) in vehicles, has been issued.
In response, and for the first time, we conducted new MF measurements
on current Japanese vehicle models in accordance with the international
standard IEC 62764-1:2022, identifying the MFD levels and their sources
at various positions within EVs, PHEVs, and ICEVs. The measured MFD
values in all vehicle types were below the reference levels recommended
by the International Commission on Non-Ionizing Radiation Protection
(ICNIRP) for public exposure. Furthermore, we performed comparative
measurements with the MF data obtained in 2013 and confirmed that the MF
levels remained similar. These findings are expected to provide
valuable insights for risk communication with the public regarding
electromagnetic fields, particularly for those concerned about MF
exposure inside electrified vehicles.
Conclusions
As
the adoption of EVs and PHEVs increases, public concern about MFs from
these vehicles has also grown. Narrowing the perception gap between
scientific risk assessments and public anxiety is essential for
effective risk communication. In this study, we conducted measurements
of MFs emitted by domestic vehicles in Japan using IEC 62764-1:2022
methods and were able to provide reliable and easily accessible data to
the public as a basis for risk communication.
The
results confirmed that the measured MFs comply with ICNIRP guidelines
and remain at levels that do not cause known acute adverse effects, such
as nerve stimulation. The locations and characteristics of the maximum
MF strengths for EVs, PHEVs, and ICEVs were identified.
For
EVs and PHEVs, the highest MF values were observed on the rear seat at a
6.5 cm measurement distance, while for ICEVs, the maximum was recorded
at the driver’s side dashboard at 20 cm. Among the vehicle types, PHEVs
showed the highest MF levels, followed by ICEVs, which had higher values
than EVs.
As a result of the frequency
analysis, both speed-dependent and speed-independent MF components were
detected across all vehicle types. Speed-dependent peaks included 6–29
Hz frequency components near the front seats, attributed to magnetized
tires. Fixed-frequency peaks included a 294 Hz component observed during
air conditioner operation. Low-frequency peaks around 1 Hz were
observed near wiring routes around the rear seat area and were
attributed to current flow during vehicle operation, with notably higher
values in the PHEV during deceleration. In ICE vehicles, low-frequency
components in the 1–5 Hz range were associated with wiper motor
operation, while higher-frequency peaks at 847 Hz and 1268 Hz were
detected but could not be clearly linked to specific sources.
A
comparison with a previous study conducted in 2013 revealed that the MF
levels are comparable to those of current vehicles as of 2025.
A
comparison with the MF measurement results from Seibersdorf Laboratory
in Austria revealed that their reported values were significantly
higher. This difference is attributed to their capturing of rapid
increases in MFD due to transient phenomena occurring on timescales
below 200 ms, which were not considered in this study, and reflects
differences in measurement conditions.
These
findings are expected to provide valuable insights for risk
communication with the general public regarding EMFs, particularly for
those concerned about MF exposure inside electrified vehicles.
As
a future perspective, as the performance of EVs continues to improve
each year, with increases in motor output and battery capacity, exposure
to MFs is expected to rise. Therefore, it is important to continue
publishing measurement results regularly in the future.
This
study focused on the vehicle itself and did not include measurements of
the charging equipment. Wireless charging systems are being developed
as an emerging technology [27,28,29,30,31],
and demonstration experiments are currently underway in Japan. As their
adoption is expected to increase in the future, opportunities for risk
communication with the general public are likely to grow. It is
therefore important to conduct MF exposure measurements in line with
public road deployment and to advance risk communication accordingly.
In
addition to passenger cars, the electrification of other vehicles such
as buses is advancing, and the introduction of new mobility
technologies, including the construction of linear motor cars, is
expected to progress in the future. As such technologies are introduced,
public concern about EMF exposure is likely to increase. Therefore, it
is important to consider conducting measurements in line with the pace
of their deployment.
Exploring RF-EMF levels in Swiss microenvironments: An evaluation of environmental and auto-induced downlink and uplink exposure in the era of 5G
Veludo AF, Stroobandt B, Van Bladel H, Sandoval-Diez N, Guxens M, Joseph W, Röösli M. Exploring RF-EMF levels in Swiss microenvironments: An evaluation of environmental and auto-induced downlink and uplink exposure in the era of 5G. Environmental Research, 2024, doi: 10.1016/j.envres.2024.120550.
Highlights
A new protocol was created to measure environmental and auto-induced RF-EMF levels.
Environmental RF-EMF was mainly attributed to downlink frequency bands
Inducing downlink and uplink traffic increased RF-EMF exposure levels notably
Auto-induced downlink exposure was mainly attributed to the 5G band at 3.5 GHz
The main contributor to auto-induced uplink exposure was the band at 2.1 GHz
Abstract
The advancement of cellular networks requires updating measurement protocols to better study radiofrequency electromagnetic field (RF-EMF) exposure emitted from devices and base stations. This paper aims to present a novel activity-based microenvironmental survey protocol to measure environmental, auto-induced downlink (DL), and uplink (UL) RF-EMF exposure in the era of 5G. We present results when applying the protocol in Switzerland. Five study areas with different degrees of urbanization were selected, in which microenvironments were defined to assess RF-EMF exposure in the population. Three scenarios of data transmission were performed using a user equipment in flight mode (non-user), inducing DL traffic (max DL), or UL traffic (max UL). The exposimeter ExpoM-RF 4, continuously measuring 35 frequency bands ranging from broadcasting to Wi-Fi sources, was carried in a backpack and placed 30cm apart from the user equipment. The highest median RF-EMF levels during the non-user scenario were measured in an urban business area (1.02 mW/m2). Here, DL and broadcasting bands contributed the most to total RF-EMF levels. Compared to the non-user scenario, exposure levels increased substantially during max DL due to the 5G band at 3.5 GHz with 50% of the median levels between 3.20-12.13 mW/m2, mostly in urban areas. Note that the time-division nature of this band prevents distinguishing between exposure contribution from DL beamforming or UL signals emitted at this frequency. The highest levels were measured during max UL, especially in rural microenvironments, with 50% of the median levels between 12.08-37.50 mW/m2. Mobile UL 2.1 GHz band was the primary contributor to exposure during this scenario. The protocol was successfully applied in Switzerland and used in nine additional countries. Inducing DL and UL traffic resulted in a substantial increase in exposure, whereas environmental exposure levels remained similar to previous studies. This data is important for epidemiological research and risk communication/management.
Conclusion
A
novel activity-based microenvironmental survey protocol was developed
and successfully carried out to disentangle environmental from
auto-induced downlink and uplink exposure in the era of 5G. The
measurements conducted in Switzerland demonstrate that higher RF-EMF
exposure levels were measured when inducing maximum downlink and uplink
traffic using a user equipment, with the 5G band at 3.5 GHz and the UL
band at 2.1 GHz the main contributors to exposure, respectively. This
data is important for epidemiological research, risk communication and
risk management, but also for future dosimetry and modelling studies.
Future research understanding auto-induced DL and UL exposure from more
realistic case scenarios remains necessary for a better characterization
of the exposure levels. Future research will consist of the application
of the proposed protocol in various countries and the comparison of the
exposure values.
6/18/2024 Note: The following paper was just published. Also see below a 2020 European Commission study I just added to this post, "Assessment of low frequency magnetic fields in electrified vehicles."
--
Do non-ionizing radiation concerns affect people's choice between hybrid and traditional cars?
Tchetchik A, Kaplan S, Rotem-Mindali O. Do non-ionizing radiation concerns affect people's choice between hybrid and traditional cars? Transportation Research Part D: Transport and Environment, Volume 131, 2024, doi: 10.1016/j.trd.2024.104226.
Abstract
The growing market for hybrid electric vehicles (HEV) has raised concerns about the long-term impacts of non-ionizing radiation (NIR) exposure. This study is the first to address the impact of NIR on consumer choice between HEV and internal combustion engine (ICE) vehicles. We explore the hypothesis that NIR is associated with a lower probability of HEV choice in the presence of NIR information and the relative effect of NIR-health concerns versus environmental attitudes and driving norms. The data are collected from a stated choice experiment and estimated via a hybrid choice model. The results show that i NIR is associated with a lower choice probability of HEV, ii NIR-dread is associated with a higher probability of choosing ICE vehicles, while skepticism about NIR is associated with a higher probability of choosing HEV, iii prompting positively or negatively framed information about NIR discourages HEV choice compared to providing no information.
Conclusions and policy recommendations
The results show the effect of NIR-associated barriers on the choice of HEV versus ICE and highlight the following policy recommendations.
First, the massive production of EVs combined with the lack of regulatory frameworks can lead to the introduction of low-cost car models with low NIR safety standards (Trentadue et al., 2020). The European Union recommends a clear regulatory framework and international standards to promote the transition toward EVs. This study showed that NIR levels negatively affect the choice of HEV, signaling to car manufacturers and policymakers that consumers are concerned about NIR levels. Accordingly, setting NIR safety standards and maintaining low NIR levels are important goals for the transition toward autonomous, connected, electric vehicles.
Second, this study showed that while NIR dread was a discouraging factor, NIR skepticism was a strong choice motivator. Thus, perceived occurrence probability is as important as NIR risk dread. As with other health issues, prevalence across the population is an important decision-making factor that, in the absence of information, may lead to self-exemption beliefs. Scientific evidence from large-scale studies regarding both short- and long-term NIR effects and their prevalence in the population and among risk groups will enable informed decision-making, help mitigate NIR dread, and establish meaningful guidelines for in-vehicle NIR levels. With climate goals requiring the transition toward EV by 2030 and with the rapid technological advancement of autonomous, connected, electric vehicles, establishing the prevalence of NIR short- and long-term health effects is important for the future of the industry.
Third, better information quality strengthens the relationship between the depiction of new vehicle technologies and perceived purchase value (Zhang et al., 2022). Our study showed that both positive and negative framing can lead to a lower choice probability when an NIR safety threshold is provided. In this study, the information that “Studies show that long-term exposure to NIR levels below 4 mG is safe” was associated with lower choice probabilities, similar to the case of negative framing, “Studies show that long-term exposure to NIR levels below 4 mG increases the health risks to health concerns.” Policymakers and manufacturers must consider information quality in terms of accuracy, clarity, ambiguity, and potential sources of confusion and decision bias. In this study, consumers used the provided threshold of 4 mG as a decision anchor, which means that consumers in some cultural contexts seek clear, “fast and frugal” evaluation criteria without engaging in complex exposure evaluations.
Finally, the model shows that travel with children is negatively associated with HEV leasing. Nevertheless, while NIR dread is negatively associated with HEV leasing, an additional interaction effect between NIR levels and travel with children was not statistically significant. These results indicate that while NIR dread is important, there is no additional health concerns particularly associated with travel with children. Hence, the decrease in the HEV leasing propensity when traveling with children may be associated with other reasons, such as vehicle reliability or other concerns that were not investigated in the current study. Notably, previous studies found a particular concern for children’s health-related to NIR from mobile phones and cellular stations. Leach and Bromwich (2018) found that two-thirds of the participants believed that mobile technology use should be restricted due to possible health risks to children’s health. P¨olzl (2011) added that 30 % of the population had strong or considerable concerns regarding NIR health risks to children, and noted that adults can be motivated to adjust their behavior to protect their children. Further research is important in other regions and contexts, to understand more thoroughly the issue of HEV leasing or purchase when traveling with children.
Eberhard J, Fröhlich J, Zahner M.
[Electromagnetic fields (EMF) in electric cars] Elektromagnetische
Felder (EMF) in Elektrofahrzeugen. Swiss Federal Office of Energy
(SFOE). 2023.
My
note:
I would be interested in seeing an English translation of this report. The exposures reported in the following English-language summary are alarming since the ICNIRP exposure limits are far too lax and inadequate to protect our health.
Summary
More
and more battery-powered electric vehicles (e-vehicles) are being put
into operation to facilitate the decarbonisation of mobility. Electric,
magnetic and electromagnetic fields (EMF) are generated in and around
vehicles by the electrical components of the drive, through battery
charging and from other diverse electronic systems used in modern
vehicles. In principle, it can be stated from a technical point of view
that all vehicles generate immissions of electromagnetic fields,
regardless of the type of drive. In addition to the electrical
parameters of the components, the design and the materials used are
significant. A feature of exposure in vehicles is that passengers may be
simultaneously exposed to a large number of sources of various
frequencies in a very confined space for hours at a time. One is also in
a volume that is (partially) shielded by the car body and window panes
coated with vapour-deposited metal.
The aim of this project was
to assess, through measurements on a selection of e-vehicles, whether
the additional EMF immissions from the electric drive and associated
components are to be judged critically as a health risk and whether
further, more in-depth clarifications are necessary.
For this
purpose, extensive measurements of the occurring low-frequency and
high-frequency EMFs extant under real operating conditions, including
the charging process, were carried out on a small selection of
series-production passenger vehicles (5 e-vehicles purely electric and
battery-powered, 1 diesel-motorised vehicle for comparison) from the
stock vehicle market in order to be able to assess the immissions on
passengers and persons staying in the vicinity of the vehicle. Since
there are currently no specific regulations for EMF in e-vehicles, the
field strengths of the measured EMF were classified against
internationally established limit recommendations (ICNIRP). The total
exhaustions of the limit values thus determined from all sources were
rather low, on average in the range of up to 5% for low-frequency
magnetic fields and up to approx. 10% for high-frequency EMF.
Occasionally, higher peak readings of low-frequency magnetic fields up
to approx. 50% of the limit values were found. In general, as is common
with magnetic fields in general, these high values are often very
localised. Moreover, due to the dynamic and complex situation in
vehicles, they often occur only sporadically and, as far as they could
be identified, are hardly directly related to the electric drive. The
measurement results of the present study are consistent with other
previous studies. Wireless power transfer (charging) was not
investigated in this project.
As far as the results of this study
can be generalised, the electric drive with energy drawn from a battery
appears to be unproblematic with regard to additional EMF.
Regardless
of the type of drive, attention must be paid to further technological
development, especially with regard to the trend toward increasing
networking and digitisation. One outstanding issue remains the
insufficient EMF regulation for vehicle interiors.
Exposure to RF Electromagnetic Fields in the Connected Vehicle: Survey of Existing and Forthcoming Scenarios
G.
Tognola, M. Bonato, M. Benini, S. Aerts, S. Gallucci, E. Chiaramello,
S. Fiocchi, M. Parazzini, B. Masini, W. Joseph, J. Wiart, P. Ravazzani.
Exposure to RF Electromagnetic Fields in the Connected Vehicle: Survey
of Existing and Forthcoming Scenarios. IEEE Access. doi:
10.1109/ACCESS.2022.3170035.
Abstract
Future vehicles will be increasingly connected to enable new
applications and improve safety, traffic efficiency and comfort, through
the use of several wireless access technologies, ranging from
vehicle-to-everything (V2X) connectivity to automotive radar sensing and
Internet of Things (IoT) technologies for intra-car wireless sensor
networks. These technologies span the radiofrequency (RF) range, from a
few hundred MHz as in intra-car network of sensors to hundreds of GHz as
in automotive radars used for in-vehicle occupant detection and
advanced driver assistance systems. Vehicle occupants and road users in
the vicinity of the connected vehicle are thus daily immersed in a
multi-source and multi-band electromagnetic field (EMF) generated by
such technologies. This paper is the first comprehensive and specific
survey about EMF exposure generated by the whole ensemble of
connectivity technologies in cars. For each technology we describe the
main characteristics, relevant standards, the application domain, and
the typical deployment in modern cars. We then extensively characterize
the EMF exposure scenarios resulting from such technologies by resuming
and comparing the outcomes from past studies on the exposure in the car.
Results from past studies suggested that in no case EMF exposure was
above the safe limits for the general population. Finally, open
challenges for a more realistic characterization of the EMF exposure
scenario in the connected car are discussed.
Complex Electromagnetic Issues Associated with the Use of Electric Vehicles in Urban Transportation
Krzysztof Gryz, Jolanta Karpowicz, Patryk Zradziński.
Complex Electromagnetic Issues Associated with the Use of Electric Vehicles in Urban Transportation. Sensors (Basel). 2022 Feb 22;22(5):1719. doi: 10.3390/s22051719.
Abstract
The electromagnetic field (EMF) in electric vehicles (EVs) affects not only drivers, but also passengers (using EVs daily) and electronic devices inside. This article summarizes the measurement methods applicable in studies of complex EMF in EVs focused on the evaluation of characteristics of such exposure to EVs users and drivers, together with the results of investigations into the static magnetic field (SMF), the extremely low-frequency magnetic field (ELF) and radiofrequency (RF) EMF related to the use of the EVs in urban transportation. The investigated EMF components comply separately with limits provided by international labor law and guidelines regarding the evaluation of human short-term exposure; however other issues need attention-electromagnetic immunity of electronic devices and long-term human exposure. The strongest EMF was found in the vicinity of direct current (DC) charging installations-SMF up to 0.2 mT and ELF magnetic field up to 100 µT-and inside the EVs-up to 30 µT close to its internal electrical equipment. Exposure to RF EMF inside the EVs (up to a few V/m) was found and recognized to be emitted from outdoor radio communications systems, together with emissions from sources used inside vehicles, such as passenger mobile communication handsets and antennas of Wi-Fi routers.
Excerpts
4.5. Health Aspects of Exposure to EMF in EVs
An EV driver’s long-lasting daily exposure to EMF, even if compliant with the exposure limits, cannot be counted to be negligible when the context of possible adverse health effects due to chronic exposure to EMF is considered. The ELF MF was classified to be a possible carcinogenic to human (2B classification) based on the epidemiologically proven elevated carcinogenic health risks in populations chronically exposed to MF exceeding 0.4 μT (attention level related to yearly averaged exposure) [38,39,40]. The level of ELF MF exposure reported in various studies focused on EMF in EVs and discussed in this article may significantly contribute to the total long-lasting exposure to drivers.
The effects of EMF exposure induced in exposed objects are frequency-dependent, but the significant majority of studies performed so far in the area of EMF safety have referred to the populations exposed to high-voltage power lines (i.e., to chronic exposure to EMF of sinusoidal power frequency), and the outcome of such observations was a base for the abovementioned 2B classification for ELF MF exceeding 0.4 μT. Because of differences in the frequency patterns of the discussed exposures (near power lines and in EVs), there needs to be very careful analysis of how far the studied health and safety outcomes from ELF EMF exposures vary in such cases, and which exposure metrics are relevant to evaluate them. Consistently, the mentioned differences in frequency characteristics of ELF EMF in EVs and EMF near regular electric power installations also need attention with respect to the exposure evaluation protocol, which in practice means that studies of the parameters of EMF exposure associated with the use of EVs require not only measurements of the RMS value (which, in practice, is usually almost equal to the RMS value of the dominant frequency component of exposure), but also attention to the higher harmonics of this exposure, the components of fundamental frequencies other than 50 Hz, the parameters of transient EMF over rapid changes in the mode of EV driving, and combined exposure including the above mentioned components.
Similar to ELF MF, RF EMF was classified by the IARC in the group of 2B carcinogenic environmental factors [41]. This component of driver EMF exposure also needs attention because of its level at least comparable to office exposure, where wireless radio communication facilities are in use and daily long-lasting exposure, potentially significantly contributing to total driver chronic exposure, combines with other components of lower frequencies (covering together exposure to: static, low frequency and radiofrequency fields).
5. Conclusions
In every urban area, there is a daily mass of passengers traveling by public transportation. Ecological and economic reasons, as well as technological development, mean that a significant percentage of the population already use EVs (trams, metro, trolleys, buses) daily, seeing as they are an increasing majority of transportation resources in various large cities. During the journeys, passengers and drivers are exposed to a specific complex EMF, with a dominant ELF component emitted by the driving systems and their supply installations, and an RF component emitted by various wireless communications systems (e.g., Wi-Fi routers located often inside vehicles, handsets of mobile communications used by passengers, and mobile communication BTS located outside vehicles). Depending on the location of the electric equipment inside the EVs, a higher exposure to EMF may affect passengers, or in some cases drivers.
Investigations into SMF, ELF and RF EMF emitted by various electrical equipment associated with the use of EV urban transportation showed that their levels, considered separately, comply with the limits provided by international labor law and guidelines aimed at protecting against the direct effects of short-term influence on humans of EMF of a particular frequency range (set up to prevent thermal load or electrical stimulation in exposed tissue) [12,13,17,20,21,22]. International guidelines and labor law do not provide rules on how to evaluate simultaneous exposure at various frequency ranges (e.g., SMF together with ELF and RF). This needs also specific attention, given that electronic devices and systems used inside EVs need to have sufficient electromagnetic immunity to ensure that their performance is not negatively affected by the impact from EMF emitted by the use of EVs.
Considering the chronic nature of exposure to EMF in EVs (in particular with respect to potential exposure to drivers when various EMF sources are located near their cabins), and the potential specific risks from exposure to EMF of complex composition in time and frequency domains, there is a need to collect research data on the complex characteristics of EMF exposure related to the use of EVs in public transportation and the associated health outcome in chronically exposed workers, as well as decreasing the level of their exposure by applying relevant preventive measures (e.g., locating indoor Wi-Fi routers, and other such electrical equipment, away from the driver’s cabin) [17,23,42,43,44].
Assessment of low frequency magnetic fields in electrified vehicles
European Commission, Joint Research Centre, Trentadue, G., Zanni, M., Martini, G. (2020). Assessment of low frequency magnetic fields in electrified vehicles, Publications Office. https://data.europa.eu/doi/10.2760/056116
Abstract
This report presents exploratory research into the low frequency (up to 400 kHz) magnetic fields generated by hybrid and electric vehicles under driving and charging conditions.
The study includes a literature survey and experimental work addressing the issues of: measurement protocols; instrument selection; and data processing, with the aim of contributing to standards development. When the experimental activities were planned, there were no published measurement procedures specific to the automotive sector; so different methodologies and instrumentation setups were explored.
Executive Summary
Electrification is currently considered one of the key options for decarbonisation of the road transport sector. The number of registered electric vehicles and of models offered on the market is continuously increasing.
Still, there are a number of issues that represent, or are perceived by consumers as, barriers to the purchase of an electric car. Limited range, high price, and lack of recharging infrastructure are the most important ones. Potential safety hazards related to exposure to magnetic fields during the use of electric vehicles are in some cases indicated as a reason for concern that can discourage people from choosing this technology.
The health effects of electromagnetic fields have been studied for several decades and there is no clear evidence of possible long-term effects. On the contrary, direct physiological effects are well known. Direct effects occur above certain thresholds and consist of electrostimulation of nerves at low frequencies (1 Hz to 10 MHz) and heating of body tissues at higher frequencies (100 kHz-300 GHz). Indirect effects are also known and include: initiation of electro-explosive devices, electric shocks or burns due to contact currents, projectile risk from ferromagnetic objects, interference with medical devices, etc.
Direct effects are linked to in-body quantities, not measurable in practice. For these reasons the international guidelines published by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) identify specific parameters to be measured, and define the related reference levels for workers and the general public.
While existing vehicle regulations address aspects such as electromagnetic compatibility and other safety related issues, for the moment there is no specific legislation regulating electromagnetic fields (EMFs) generated by vehicles. There are a few recently published procedures that are recommended to assess EMFs in the automotive sector which differ in the level of detail of the protocol description and certain requirements.
This study was carried out with the following objectives in mind:
To provide a clear picture of current knowledge in this field by means of a comprehensive literature survey. A summary of the main findings is available in chapter 3.2;
To gather experimental data on low frequency magnetic fields generated by electrified vehicles of the latest generation through ad-hoc experiments carried out in the JRC’s VELA laboratories (section 5);
To support the development of a standard test procedure in anticipation of future legislation on type approval of electric vehicles (sections 6, 7).
In total, nine different electrified passenger cars, including both pure electric vehicles and hybrids, were tested in the JRC’s facilities. The main focus was the assessment of the magnetic flux density (B-field), in the time and frequency domains, inside the vehicle under various operating conditions. The instrument used for the campaign follows the guidelines set in IEC standard 61786-1:2013 “Measurement of DC Magnetic, AC Magnetic and AC Electric Fields from 1 Hz to 100 kHz with Regard to Exposure of Human Beings – Part 1: Requirements for measuring instruments”.
It is important to stress that when this exploratory work started, no standard for the assessment of low frequency magnetic fields inside vehicles was available. As a consequence, the protocol used changed significantly in response to the experience gained in the course of the work. Measurement locations corresponding to different parts of the human body (head, thorax and feet) were defined inside each vehicle. The vehicles were operated according to a driving cycle that included hard acceleration and braking events, as well as constant speed phases. Being a completely new activity for the JRC, solutions to a number of technical challenges were found, in particular regarding reproducibility of the driving cycle and proper data acquisition.
Results show that the highest B-field values were recorded in locations corresponding to the feet positions, during hard accelerations and regenerative braking. Acceleration and braking phases, rather than constant speed phases, were responsible for the highest peaks of current and consequently B-field; B-field values were also influenced by vehicle configuration and use during the test (air conditioning, regenerative breaking).
The study has identified some potential issues related to the requirements of the instrumentation and the test procedure that have to be further investigated and solved in view of a future regulation.
A complete characterization of the magnetic fields arising during vehicle operation would require correlation of instantaneous B – field values with the currents in the conductors within the vehicle, and with the vehicle’s speed. This task represents a significant challenge in terms of measurement instrumentation that has not yet been fully solved. Ad-hoc tools must be developed to acquire and synchronize all relevant parameters, including encrypted parameters from the vehicle's electronic control unit. Moreover, it turned out that the frequency resolution of probes appropriate for measuring human exposure to magnetic fields (i.e. probes complying with European Directive 2013/35/UE, ICNIRP 2010 and 1998 guidelines, and IEC 61786-2 -Measurement of DC magnetic, AC magnetic and AC electric fields from 1 Hz to 100 kHz with regard to exposure of human beings – Part 2: Basic standard for measurements) might not be sufficient for accurate frequency-domain characterisation of the field. This implies that specific requirements are needed for instruments to be used for measurements of exposure to magnetic fields inside vehicles. The other issue related to the instrument used is that raw B - field values were not available during time-domain measurements, since the probe only output the percentage of the ratio between the measured field and the reference level, limiting the possibilities for post-processing. For this reason, further measurements, whose results are pending publications, were made with a second instrument in collaboration with ENEA, the Italian Agency for New Technologies, Energy and Sustainable Economic Development, with the aim to acquire instantaneous magnetic field values to quantify a hypothesised underestimation of values recorded by the instrument used previously.
Recently published measurement procedures for magnetic fields inside vehicles recommend an approach similar to that described here in terms of used instrumentation and operating conditions of the vehicle under test. However, these protocols differ in the level of detail concerning both the procedure and the requirements for the instrumentation. An effort to harmonize and better define the so far proposed standards is desirable.
In a future with massively increased production of electric vehicles and inadequate regulation, manufacturers might seek to reduce production costs by saving on protections against EMF exposure, bringing car models with lower EMF safety standards to market. To prevent this, an appropriate regulatory standard, for type approval or in-use compliance, is required. This would also provide a clear legislative framework with which market players in the automotive sector could plan their investments with less uncertainty
Review of Safety and Exposure Limits of Electromagnetic Fields (EMF) in Wireless Electric Vehicle Charging (WEVC) Applications
Erdem Asa, Mostak Mohammad, Omer C. Onar, Jason Pries, Veda Galigekere, Gui-Jia Su. Review of Safety and Exposure Limits of Electromagnetic Fields (EMF) in Wireless Electric Vehicle Charging (WEVC) Applications.
2020 IEEE Transportation Electrification Conference & Expo (ITEC).23-26 June 2020. doi:
10.1109/ITEC48692.2020.9161597.
Abstract
This study reviews the
exposure limits and safety of intermediate frequency (IF)
electromagnetic field (EMF) emissions for wireless electric vehicle
charging (WEVC) applications. A review of the electromagnetic field
exposure limits identified in international guidelines are presented. An
overview of the electromagnetic field shielding technologies is
provided including recommended geometries, materials, and performances
of the methods available in the literature. Available laboratory results
of EMF emissions are summarized considering several wireless power
transfer studies in different power levels. Possible EMF reduction
techniques are discussed with shielding practices and ORNL [Oak Ridge National Laboratory] case studies.
Also, living object detection (LOD) and foreign object detection (FOD)
methods are reviewed from a safety aspect.
Conclusions
This study reviews and compiles the EMF emission limitations identified in international guidelines and standards including IEEE, ICNIRP, ACGIH, and SAE. EMF emissions can be substantial particularly at high-power transfer levels and misaligned conditions and should be reduced below the limits identified in the ICNIRP 2010 guidelines which are more conservative and thought to be safer. This study also provides a review of the shielding methods and presents two case studies from ORNL experiences and practices on EMF shielding. EMF exposure levels and shielding methodologies for high-power and dynamic wireless power transfer applications should be analyzed in future studies with possible standards development activities.
Electromagnetic Exposure Study on a Human Located inside the Car Using the Method of Auxiliary Sources
Jeladze VB, Nozadze TR, Tabatadze VA, et al. Electromagnetic Exposure Study on a Human Located inside the Car Using the Method of Auxiliary Sources. J Communications Technology Electronics. 65(5): 457-464. May 2020.
Abstract
The article studies the effect of the electromagnetic field of wireless communications on a human inside a car in the frequency ranges of 450, 900, and 1800 MHz, corresponding to the operational range of police radios and modern mobile phones. A comparative analysis of the influence of the Earth’s surface under the car is presented. The results of numerical calculations using the Method of Auxiliary Sources show the presence of resonance phenomena and a high reactive field inside the car, which leads to an undesirable increase in the level of absorbed energy in human tissues.
Conclusions
The Method of Auxiliary Sources was used to study the exposure of the electromagnetic field of a mobile phone’s antenna on a human inside a car. The calculations took into account the effect of Earth’s reflective surface under the car. The results showed that high-amplitude reactive fields inside the car can lead to a multiple increase in the SAR coefficient in human tissues compared to values obtained in the free space. It is recommended to reduce the duration of mobile phone calls inside a car.
-- Patients with pacemakers or defibrillators do not need to worry about e-Cars: An observational study
Lennerz C, Horlbeck L, Weigand S, Grebmer C, Blazek P, Brkic A, Semmler V, Haller B, Reents T, Hessling G, Deisenhofer I, Lienkamp M, Kolb C, O'Connor M. Technol Health Care. 2019 Nov 8. doi: 10.3233/THC-191891.
Abstract
BACKGROUND: Electric cars are increasingly used for public and private transportation and represent possible sources of electromagnetic interference (EMI). Potential implications for patients with cardiac implantable electronic devices (CIED) range from unnecessary driving restrictions to life-threatening device malfunction. This prospective, cross-sectional study was designed to assess the EMI risk of electric cars on CIED function.
METHODS: One hundred and eight consecutive patients with CIED presenting for routine follow-up between May 2014 and January 2015 were enrolled in the study. The participants were exposed to electromagnetic fields generated by the four most common electric cars (Nissan Leaf, Tesla Model S, BMW i3, VW eUp) while roller-bench test-driving at Institute of Automotive Technology, Department of Mechanical Engineering, Technical University, Munich. The primary endpoint was any abnormalities in CIED function (e.g. oversensing with pacing-inhibition, inappropriate therapy or mode-switching) while driving or charging electric cars as assessed by electrocardiographic recordings and device interrogation.
RESULTS: No change in device function or programming was seen in this cohort which is representative of contemporary CIED devices. The largest electromagnetic field detected was along the charging cable during high current charging (116.5 μT). The field strength in the cabin was lower (2.1-3.6 μT).
CONCLUSIONS: Electric cars produce electromagnetic fields; however, they did not affect CIED function or programming in our cohort. Driving and charging of electric cars is likely safe for patients with CIEDs.
Pääkkönen
R, Korpinen L. Low Frequency Magnetic Fields Inside Cars. Radiation
Protection Dosimetry. 2019. 187(2):268-271. doi: 10.1093/rpd/ncz248.
Abstract
Magnetic
fields were compared inside passenger seats of electric, petrol and
hybrid cars. While driving about 5 km in an urban environment, values
were recorded and compared between car types. The magnetic flux
densities of the cars were less than 2.6 μT. The magnitudes of the
magnetic fields of petrol cars and hybrid cars were about the same and
slightly lower for electric cars. Based on our measurements, values were
less than 3% of the guidelines given for the general population or
people using pacemakers.
Long-Term Monitoring of Extremely Low Frequency Magnetic Fields in Electric Vehicles
Yang L, Lu M, Lin J, Li C, Zhang C, Lai Z, Wu T.
Long-Term Monitoring of Extremely Low Frequency Magnetic Fields in Electric Vehicles.
Int J Environ Res Public Health. 2019 Oct 7;16(19). pii: E3765. doi: 10.3390/ijerph16193765.
Abstract
Extremely low frequency (ELF) magnetic field (MF) exposure in electric vehicles (EVs) has raised public concern for human health. There have been many studies evaluating magnetic field values in these vehicles. However, there has been no report on the temporal variation of the magnetic field in the cabin . This is the first study on the long-term monitoring of actual MFs in EVs. In the study, we measured the magnetic flux density (B) in three shared vehicles over a period of two years. The measurements were performed at the front and rear seats during acceleration and constant-speed driving modes. We found that the B amplitudes and the spectral components could be modified by replacing the components and the hubs, while regular checks or maintenance did not influence the B values in the vehicle. This observation highlights the necessity of regularly monitoring ELF MF in EVs, especially after major repairs or accidents, to protect car users from potentially excessive ELF MF exposure. These results should be considered in updates of the measurement standards. The ELF MF effect should also be taken into consideration in relevant epidemiological studies.
Effect of static magnetic field of electric vehicles on driving performance and on neuro-psychological cognitive functions
He Y, Sun W, Leung PS, Chow YT. Effect of static magnetic field of electric vehicles on driving performance and on neuro-psychological cognitive functions. Int J Environ Res Public Health. 2019 Sep 12;16(18). pii: E3382. doi: 10.3390/ijerph16183382.
Abstract
Human
neuropsychological reactions and brain activities when driving electric
vehicles (EVs) are considered as an issue for traffic and public safety
purposes; this paper examined the effect of the static magnetic field
(SMF) derived from EVs. A lane change task was adopted to evaluate the
driving performance; and the driving reaction time test and the reaction
time test were adopted to evaluate the variation of the
neuro-psychological cognitive functions. Both the sham and the real
exposure conditions were performed with a 350 μT localized SMF in this
study; 17 student subjects were enrolled in this single-blind
experiment. Electroencephalographs (EEGs) of the subjects were adopted
and recorded during the experiment as an indicator of the brain activity
for the variations of the driving performance and of the cognitive
functions. Results of this study have indicated that the impact of the
given SMF on both the human driving performance and the cognitive
functions are not considerable; and that there is a correlation between
beta sub-band of the EEGs and the human reaction time in the analysis. Open access paper: https://www.mdpi.com/1660-4601/16/18/3382
--
Possible Health Impacts of Advanced Vehicles Wireless Technologies
Judakova Z, Janousek L. Possible Health Impacts of Advanced Vehicles Wireless Technologies. Transportation Research Procedia. 40:1404-1411. 2019. https://doi.org/10.1016/j.trpro.2019.07.194
Abstract
Modern vehicles contain various security systems including vehicular networking where vehicles receive relevant traffic information using wireless communications from their peers. This wireless communication is mediated by the radiofrequency electromagnetic field. Exposure to electromagnetic fields caused by the transportation system is a cause of concern for many people. Plenty of dosimetric analysis of electromagnetic field carried out by various research groups found out the highest exposure values in the transport. How long-term effects of these fields affect the human organism and what is the mechanism of action, are questions without known answers. Several studies point to the possible association of different diseases with electromagnetic field exposure. The key to understanding the effect of the electromagnetic field on the human organism is to reveal the mechanism of action of these fields. Open access paper: https://www.sciencedirect.com/science/article/pii/S2352146519303643?via%3Dihub
-- Evaluating extremely low frequency magnetic fields in the rear seats of the electric vehicles
Lin
J, Lu M, Wu T, Yang L, Wu TN. Evaluating extremely low frequency
magnetic fields in the rear seats of the electric vehicles. Radiation
Protection Dosimetry. 182(2):190-199. Dec 2018.
Abstract
In
the electric vehicles (EVs), children can sit on a safety seat
installed in the rear seats. Owing to their smaller physical dimensions,
their heads, generally, are closer to the underfloor electrical systems
where the magnetic field (MF) exposure is the greatest. In this study,
the magnetic flux density (B) was measured in the rear seats of 10
different EVs, for different driving sessions. We used the measurement
results from different heights corresponding to the locations of the
heads of an adult and an infant to calculate the induced electric field
(E-field) strength using anatomical human models. The results revealed
that measured B fields in the rear seats were far below the reference
levels by the International Commission on Non-Ionizing Radiation
Protection. Although small children may be exposed to higher MF
strength, induced E-field strengths were much lower than that of adults
due to their particular physical dimensions.
-- Radiofrequencies in cars: A public health threat According to Theodore P. Metsis, Ph.D., an electrical, mechanical, and environmental engineer from Athens, Greece, modern conventional gas- and diesel-powered automobiles incorporate many EMF-emitting devices.
"EMFs in a car in motion with brakes applied + ABS activation may well exceed 100 mG. Adding RF radiation from blue tooth, Wi Fi, the cell phones of the passengers, the 4G antennas laid out all along the major roads plus the radars of cars already equipped with, located behind, left or right of a vehicle, the total EMF and EMR fields will exceed any limits humans can tolerate over a long period of time."
-- Mobile Phone Antenna’s EM Exposure Study on a Human Model Inside the Car Nozadze T, Jeladze V, Tabatadze V, Petoev I, Zaidze R. Mobile phone antenna’s EM exposure study on a homogeneous human model inside the car. 2018 XXIIIrd International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED). Tlibisi, Georgia. Sep 24-27, 2019. DOI: 10.1109/DIPED.2018.8543310
Abstract
Mobile phones’ radiation influence on a homogenous human model located inside a car is studied in this research. One of the novelty of proposed research is earth surface influence consideration under the car on EM field formation inside it. The inner field and its amplification by the car’s walls that in some cases act like a resonator are studied. The problem was solved numerically using the Method of Auxiliary Sources. Numerical simulations were carried out at the 450, 900, 1800 [MHz] standard communication frequencies. Obtained results showed the presence of resonant phenomena inside the car.
Excerpts
On Fig. 9 are presented point SAR peak values at the considered non-resonant and resonant frequencies. As it seen, point SAR peak values for resonant frequencies are approximately 5–8 times higher than non-resonant frequencies.
Based on the analysis of the obtained results we can conclude that at some frequencies car’s walls acts as the resonator and amplifies the field radiated from the mobile phones; which is cause of high point SAR values inside the human body. For the low frequency the EM field energy deeply penetrates into the human body, while for the high frequencies is mostly absorbed in the skin.
Conclusions
The mobile phone’s EM exposure problem for a homogenous human model inside the car is studied using the MAS. MAS were used to simulate earth reflective surface. The obtained results, conducted with the MAS based program package, showed the presence of resonance and reactive fields inside the car, that causes high SAR in human tissues. The reason of this is that at the considered frequencies car’s metallic surface acts as the resonator. So, it isn’t desirable speak on phones for a long time inside the car, that can be hazardous for the cell phone users located in it. https://ieeexplore.ieee.org/document/8543310
-- Electric cars
and EMI with cardiac implantable electronic devices: A cross-sectional evaluation
Lennerz C,
O'Connor M, Horlbeck L, Michel J, Weigand S, Grebmer C, Blazek P, Brkic A,
Semmler V, Haller B, Reents T, Hessling G, Deisenhofer I, Whittaker P, Lienkamp
M, Kolb C. Letter: Electric cars and electromagnetic interference with cardiac implantable electronic devices: A cross-sectional evaluation. Annals of
Internal Medicine. Apr 24, 2018.
No Abstract
Excerpts
Cardiac implantable electronic devices (CIEDs) are considered
standard care for bradycardia, tachycardia, and heart failure. Electromagnetic
interference (EMI) can disrupt normal function … Electric cars represent a
potential source of EMI. However, data are insufficient to determine their
safety or whether their use should be restricted in patients with CIEDs.
Objective: To assess
whether electric cars cause EMI and subsequent CIED dysfunction.
Methods and Findings: We approached
150 consecutive patients with CIEDs seen in our electrophysiology clinic … 40
patients declined to participate, and 2 withdrew consent … Participants were
assigned to 1 of 4 electric cars with the largest European market share…we
excluded hybrid vehicles.
Participants sat in the front seat while cars ran on a roller
test bench … Participants then charged the same car in which they had sat.
Finally, investigators drove the cars on public roads.
Field strength was generally highest during charging (30.1 to
116.5 µT) and increased as the charging current increased. Exposure during
charging was at least an order of magnitude greater than that measured within 5
cm of the CIED in the front seat (2.0 to 3.6 µT). Field strength did not differ
between the front and back seats. Peak field strength measured outside the cars
ranged between the values measured during charging and those measured within
the cars during testing … Field strength measured inside the cars during road
driving was similar to that measured during test bench studies.
We found no
evidence of EMI with CIEDs ...The electrocardiographic recorder did observe
EMI, but CIED function and programming were unaffected.
Our sample
was too small to detect rare events ... Nevertheless, other evidence supports a lack of EMI
with CIEDs. Magnetic fields are generated in gasoline-powered vehicles if the
vehicles' steel-belted tires are magnetized (3); average fields of
approximately 20 µT were reported in the back seat of 12 models, and those as
high as 97 µT were reported close to the tires (4). Similar values were
reported in electric trains and trams (5). The lack of anecdotal reports of
CIED malfunction associated with such transportation is consistent with our
findings.
Electric cars
seem safe for patients with CIEDs, and restrictions do not appear to be
required. However, we recommend vigilance to monitor for rare events,
especially those associated with charging and proposed “supercharging”
technology.
-- Evaluating ELF magnetic fields in the rear seats of electric vehicles
Lin J, Lu M, Wu T, Yang L, Wu T. Evaluating extremely low frequency magnetic fields in the rear seats of the electric vehicles.
Radiat Prot Dosimetry. 2018 Mar 23. doi: 10.1093/rpd/ncy048.
Abstract
In the electric vehicles (EVs), children can sit on a
safety seat installed in the rear seats. Owing to their smaller
physical dimensions, their heads, generally, are closer to the
underfloor electrical systems where the magnetic field (MF) exposure is
the greatest. In this study, the magnetic flux density (B) was measured
in the rear seats of 10 different EVs, for different driving sessions.
We used the measurement results from different heights corresponding to
the locations of the heads of an adult and an infant to calculate the
induced electric field (E-field) strength using anatomical human models.
The results revealed that measured B fields in the rear seats were far
below the reference levels by the International Commission on
Non-Ionizing Radiation Protection. Although small children may be
exposed to higher MF
strength, induced E-field strengths were much lower than that of adults
due to their particular physical dimensions. https://www.ncbi.nlm.nih.gov/pubmed/29584925
Excerpts
Small
children and infants sitting in a safety seat at the rear part of the
vehicle is a common occurrence. Children have smaller physical
dimensions and, thus, their heads are generally much closer to the car
floor, where the MF strength has been reported to be higher due to tire
magnetization and the operation of the underfloor electrical systems (6,
7). The matter of children being potentially subject to greater
magnetic field exposure may be relevant as leukemia is the most common
type of childhood cancer (8). In particular, Ahlbom et al. (9) and
Greenland et al. (10) indicated that the exposure to 50 and 60 Hz MF
exceeding 0.3–0.4 μT may result in an increased risk for childhood
leukemia although a satisfactory causal relationship has not yet been
reliably demonstrated. Also, it was reported that a combination of weak,
steady and alternating MF could modify the radical concentration, which
had the potential to lead to biologically significant changes (11).
... the B field values
measured at location #4 (floor in from of rear seat) were the highest,
followed by values from location #3 (rear seat cushion), #2 (child’s
head position) and #1 (adult’s head position) (p < 0.012, α = 0.05/3 = 0.017). There was a significant difference between the driving scenarios (F(3, 117) = 3.72, p = 0.013). The acceleration and deceleration scenarios generated higher B fields compared with the stationary and the 40 km/h driving scenarios (p < 0.01, α = 0.05/3 = 0.017) while no difference was identified between acceleration and deceleration (p = 0.16).
...
The results demonstrate that the induced E-field strength was lower for the infant model compared with that of the adult in terms of both the head and body as a whole.
The infant was reported to have higher electrical conductivity (29)
but there was no database dedicated to the infant. Furthermore, below 1
MHz, the database was hard to be measured and the uncertainty was large (30). Therefore, we would not include the issue in the study. Although several SCs (spectral components) on higher frequencies have been observed (can
spread to 1.24 kHz), the spectral analysis revealed that the SCs
concentrated on bands below 1000 Hz. The EVs under test used aluminum
alloy wheel rims, which have low magnetic permeability. However, the
steel wire in the reinforcing belts of radial tires pick up magnetic
fields from the terrestrial MF. When the tires spin, the magnetized
steel wire in the reinforcing belts generates ELF MF usually below 20
Hz, that can exceed 2.0 μT at seat level in the passenger compartment (6).
The measurement did not identify the ELF MF by different sources
because the purpose of the study was to investigate the realistic
exposure scenario for the occupants. To note, degaussing the tires or
using the fiberglass belted tires can eliminate this effect and provide
the MF results solely introduced by the operation of the electrified
system. ICNIRP proposed guidelines to evaluate the compliance of the non-sinusoidal signal exposure(3). The measurements rendered the maximal B
field at the level of one-tenth to several μT, far below the reference
level of the guidelines (e.g. 200 μT for 20–400 Hz). The similar
non-sinusoidal MF signal magnitudes can only account for 6–10% of the
reference levels according to the previous reports(32).
However, as noted in the Introduction, ‘… 50 and 60 Hz MF exceeding
0.3–0.4 μT may result in an increased risk for childhood leukemia’.
Therefore, it is necessary to measure the MF in the EVs to limit the
exposure and for the purpose of epidemiological studies.
In
this study, we measured ELF MF in the rear seats of ten types of EVs.
The measurements were performed for four different driving scenarios.
The measurement results were analyzed to determine the worst-case
scenario and those values were used for simulations. We made numerical
simulations to compare the induced E-field strength due to the physical
difference between children and adults using detailed anatomical models.
The results support the contention that the MF in the EVs that we
tested was far below the reference levels of the ICNIRP guidelines.
Furthermore, our findings show that children would not be more highly
exposed compared to adults when taking into consideration of their
physical differences. However, the measurement results indicated that
further studies should be performed to elucidate the concerns on the
incidence of the childhood leukemia for infant and child occupants.
-- Evaluation of electromagnetic exposure during 85 kHz wireless power transfer for electric vehicles SangWook
Park. Evaluation of Electromagnetic Exposure During 85 kHz Wireless
Power Transfer for Electric Vehicles. IEEE Transactions on Magnetics.
Volume: PP, Issue: 99. Sep 1, 2017. doi: 10.1109/TMAG.2017.2748498.
Abstract
The
external fields in the proximity of electric vehicle (EV) wireless
power transfer (WPT) systems requiring high power may exceed the limits
of international safety guidelines. This study presents dosimetric
results of an 85 kHz WPT system for electric vehicles. A WPT system for
charging EVs is designed and dosimetry for the system is evaluated for
various exposure scenarios: a human body in front of the WPT system
without shielding, with shielding, with alignment and misalignment
between transmitter and receiver, and with a metal plate on the system
for vehicle mimic floor pan. The minimum accessible distances in
compliance are investigated for various transmitting powers. The maximum
allowable transmitting power are also investigated with the limits of
international safety guidelines and the dosimetric results.
-- Electric and magnetic fields <100
KHz in electric and gasoline-powered vehicles
Tell RA,
Kavet R. Electric and magnetic fields <100 KHz in electric and
gasoline-powered vehicles. Radiat Prot Dosimetry. 2016 Dec;172(4):541-546.
Abstract
Measurements
were conducted to investigate electric and magnetic fields (EMFs) from 120 Hz
to 10 kHz and 1.2 to 100 kHz in 9 electric or hybrid vehicles and 4 gasoline
vehicles, all while being driven. The range of fields in the electric vehicles
enclosed the range observed in the gasoline vehicles. Mean magnetic fields
ranged from nominally 0.6 to 3.5 µT for electric/hybrids depending on the
measurement band compared with nominally 0.4 to 0.6 µT for gasoline vehicles.
Mean values of electric fields ranged from nominally 2 to 3 V m-1 for
electric/hybrid vehicles depending on the band, compared with 0.9 to 3 V m-1 for
gasoline vehicles. In all cases, the fields were well within published exposure
limits for the general population. The measurements were performed with Narda
model EHP-50C/EHP-50D EMF analysers that revealed the presence of spurious
signals in the EHP-50C unit, which were resolved with the EHP-50D model.
-- Passenger exposure to magnetic fields due to the batteries of an electric vehicle
Pablo Moreno-Torres Concha; Pablo Velez; Marcos Lafoz; Jaime
R. Arribas. Passenger Exposure to Magnetic Fields due to the Batteries
of an Electric Vehicle. IEEE Transactions on Vehicular Technology. 65(6):4564-4571. Jun 2016.
Abstract
In electric vehicles, passengers sit very close to an
electric system of significant power. The high currents achieved in these
vehicles mean that the passengers could be exposed to significant magnetic
fields (MFs). One of the electric devices present in the power train are the
batteries. In this paper, a methodology to evaluate the MF created by these batteries
is presented. First, the MF generated by a single battery is analyzed using
finite-elements simulations. Results are compared with laboratory measurements,
which are taken from a real battery, to validate the model. After this, the MF
created by a complete battery pack is estimated, and results are discussed.
Conclusion
Passengers inside an EV could be exposed to MFs of
considerable strength when compared with conventional vehicles or to other
daily exposures (at home, in the office, in the street, etc.). In this paper,
the MF created by the batteries of a particular electric car is evaluated from
the human health point of view by means of finite-elements simulations,
measurements, and a simple analytical approximation, obtaining an upper bound
for the estimated MF generated by a given battery pack. These results have been
compared with ICNIRP's recommendations concerning exposure limitation to
low-frequency MFs, finding that the field generated by this particular battery
pack should be below ICNIRP's field reference levels, and conclusions
concerning the influence of the switching frequency have been drawn. Finally,
some discussion regarding other field sources within the vehicle and different
vehicles designs has been presented. Due to the wide variety of both available
EVs and battery stacks configurations, it is recommended that each vehicle
model should be individually assessed regarding MF exposure.
Vassilev A et
al. Magnetic Field Exposure Assessment in Electric Vehicles. IEEE Transactions
on Electromagnetic Compatibility. 57(1):35-43. Feb 2015.
Abstract
This article
describes a study of magnetic field exposure in electric vehicles (EVs). The
magnetic field inside eight different EVs (including battery, hybrid, plug-in
hybrid, and fuel cell types) with different motor technologies (brushed direct
current, permanent magnet synchronous, and induction) were measured at
frequencies up to 10 MHz. Three vehicles with conventional powertrains were
also investigated for comparison. The measurement protocol and the results of
the measurement campaign are described, and various magnetic field sources are
identified. As the measurements show a complex broadband frequency spectrum, an
exposure calculation was performed using the ICNIRP “weighted peak” approach.
Results for the measured EVs showed that the exposure reached 20% of the ICNIRP
2010 reference levels for general public exposure near to the battery and in
the vicinity of the feet during vehicle start-up, but was less than 2% at head
height for the front passenger position. Maximum exposures of the order of 10%
of the ICNIRP 2010 reference levels were obtained for the cars with
conventional powertrains. http://ieeexplore.ieee.org/abstract/document/6915707/
-- Characterization of ELF magnetic fields from diesel, gasoline and hybrid cars under controlled conditions
Hareuveny
R, Sudan M, Halgamuge MN, Yaffe Y, Tzabari Y, Namir D, Kheifets L.
Characterization of Extremely Low Frequency Magnetic Fields from Diesel,
Gasoline and Hybrid Cars under Controlled Conditions. Int J Environ Res
Public Health. 2015 Jan 30;12(2):1651-1666.
Abstract
This study characterizes extremely low frequency (ELF) magnetic field (MF) levels in 10 car models.
Extensive
measurements were conducted in three diesel, four gasoline, and three
hybrid cars, under similar controlled conditions and negligible
background fields. Averaged over all four seats under various
driving scenarios the fields were lowest in diesel cars (0.02 μT),
higher for gasoline (0.04-0.05 μT) and highest in hybrids (0.06-0.09
μT), but all were in-line with daily exposures from other sources.
Hybrid cars had the highest mean and 95th percentile MF levels, and an
especially large percentage of measurements above 0.2 μT. These
parameters were also higher for moving conditions compared to standing
while idling or revving at 2500 RPM and higher still at 80 km/h compared
to 40 km/h. Fields in non-hybrid cars were higher at the front seats,
while in hybrid cars they were higher at the back seats, particularly
the back right seat where 16%-69% of measurements were greater than 0.2
μT. As our results do not include low frequency fields (below 30
Hz) that might be generated by tire rotation, we suggest that net
currents flowing through the cars' metallic chassis may be a possible
source of MF. Larger surveys in standardized and well-described settings
should be conducted with different types of vehicles and with spectral
analysis of fields including lower frequencies due to magnetization of
tires.
Excerpts
Previous
work suggests that major sources of MF in cars include the tires and
electric currents [4,5]. The level of MF exposure depends on the
position within the vehicle (e.g., proximity to the MF sources) and can
vary with different operating conditions, as changes to engine load can
induce MFs through changes in electric currents. Scientific
investigations of the levels of MF in cars are sparse: only one study
evaluated fields only in non-hybrid cars [6], two studies of hybrid cars
have been carried out [4,7], and few studies have systematically
compared exposures in both hybrid and non-hybrid cars [8,9,10,11,12],
some based on a very small number of cars
In
hybrid cars, the battery is generally located in the rear of the car
and the engine is located in the front. Electric current flows between
these two points through cables that run underneath the passenger cabin
of the car. This cable is located on the left for right-hand driving
cars and on the right for left-hand driving cars. Although in principle
the system uses direct current (DC), current from the alternator that is
not fully rectified as well as changes to the engine load, and
therefore the current level, can produce MFs which are most likely in
the ELF range. While most non-hybrid cars have batteries that are
located in the front, batteries in some of them are located in the rear
of the car, with cables running to the front of the car for the
electrical appliances on the dashboard. In this study, all gasoline and
diesel cars had batteries located in the front of the car.
...the
percent of time above 0.2 µT was the most sensitive parameter of the
exposure. Overall, the diesel cars measured in this study had the lowest
MF readings (geometric mean less than 0.02 μT), while the hybrid cars
had the highest MF readings (geometric mean 0.05 μT). Hybrid cars had
also the most unstable results, even after excluding outliers beyond the
5th and 95th percentiles. With regard to seat position, after adjusting
for the specific car model, gasoline and diesel cars produced higher
average MF readings in the front seats, while hybrid cars produced the
highest MF readings in the back right seat (presumably due to the
location of the battery). Comparing the different operating conditions,
the highest average fields were found at 80 km/h, and the differences
between operating conditions were most pronounced in the back right seat
in hybrid cars. Whether during typical city or highway driving, we
found lowest average fields for diesel cars and highest fields for
hybrid cars.
Previous
works suggest that the magnetization of rotating tires is the primary
source of ELF MFs in non-hybrid cars [5,15]. However, the relatively
strong fields (on the order of a few μT within the car) originating from
the rotating tires are typically at 5–15 Hz frequencies, which are
filtered by the EMDEX II meters. ....
Overall,
the average MF levels measured in the cars’ seats were in the range of
0.04–0.09 μT (AM) and 0.02–0.05 μT (GM). These fields are well below the
ICNIRP [17] guidelines for maximum general public exposure (which range
from 200 μT for 40 Hz to 100 μT for 800 Hz), but given the complex
environments in the cars, simultaneous exposure to non-sinusoidal fields
at multiple frequencies must be carefully taken into account.
Nevertheless, exposures in the cars are in the range of every day
exposure from other sources. Moreover, given the short amount of time
that most adults and children spend in cars (about 30 minutes per day
based on a survey of children in Israel (unpublished data), the relative
contribution of this source to the ELF exposure of the general public
is small. However, these fields are in addition to other exposure
sources. Our results might explain trends seen in other daily exposures:
slightly higher average fields observed while travelling (GM = 0.096
μT) relative to in bed (GM = 0.052 μT) and home not in bed (GM = 0.080
μT) [1]. Similarly, the survey of children in Israel found higher
exposure from transportation (GM = 0.092 µT) compared to mean daily
exposures (GM = 0.059 µT). Occupationally, the GM of time-weighted
average for motor vehicle drivers is 0.12 μT [18].
-- Design guidelines to reduce the magnetic field in electric
vehicles
SINTEF, Jan 6, 2014
Based on the measurements and on extensive simulation work
the project arrived on the following design guidelines to, if necessary,
minimize the magnetic field in electric vehicles.
Cables
For
any DC cable carrying significant amount of current, it should be made in
the form of a twisted pair so that the currents in the pair always flow in
the opposite directions. This will minimise its EMF emission.
For
three-phase AC cables, three wires should be twisted and made as close as
possible so as to minimise its EMF emission.
All
power cables should be positioned as far away as possible from the
passenger seat area, and their layout should not form a loop. If cable
distance is less than 200mm away from the passenger seats, some forms of
shielding should be adopted.
A
thin layer of ferromagnetic shield is recommended as this is
cost-effective solution for the reduction of EMF emission as well EMI
emission.
Where
possible, power cables should be laid such a way that they are separated
from the passenger seat area by a steel sheet, e.g., under a steel
metallic chassis, or inside a steel trunk.
Motors
Where
possible, the motor should be installed farther away from the passenger
seat area, and its rotation axis should not point to the seat region.
If
weight permits, the motor housing should be made of steel, rather than
aluminium, as the former has a much better shielding effect.
If
the distance of the motor and passenger seat area is less than 500mm, some
forms of shielding should be employed. For example, a steel plate could be
placed between the motor and the passenger seat region
Motor
housing should be electrically well connected to the vehicle metallic chassis
to minimise any electrical potential.
Inverter
and motor should be mounted as close as possible to each other to minimise
the cable length between the two.
Batteries
Since
batteries are distributed, the currents in the batteries and in the
interconnectors may become a significant source for EMF emission, they
should be place as far away as possible from the passenger seat areas. If
the distance between the battery and passenger seat area is less than
200mm, steel shields should be used to separate the batteries and the
seating area.
The
cables connecting battery cells should not form a loop, and where
possible, the interconnectors for the positive polarity should be as close
as possible to those of the negative polarity.
-- Magnetic fields in electric cars won't kill you
Jeremy Hsu, IEEE Spectrum, May 5, 2014
Summary
“The study, led by SINTEF, an independent research
organization headquartered in Trondheim, Norway, measured the electromagnetic
radiation—in the lab and during road tests—of seven different electric cars, one hydrogen-powered car, two
gasoline-fueled cars and one diesel-fueled car. Results from all conditions
showed that the exposure was less than 20 percent of the limit recommended by
the International Commission on Non-Ionizing Radiation
Protection (ICNIRP).”
“Measurements taken inside the vehicles—using a test dummy
with sensors located in the head, chest and feet—showed exposure at less than 2
percent of the non-ionizing radiation limit at head-height. The highest electromagnetic field readings—still less than 20
percent of the limit—were found near the floor of the electric cars, close to
the battery. Sensors picked up a burst of radiation that same level, when the
cars were started.”
-- ELF magnetic fields in electric and
gasoline-powered vehicles
Tell RA, Sias
G, Smith J, Sahl J, Kavet R. ELF magnetic fields in electric and
gasoline-powered vehicles. Bioelectromagnetics. 2013
Feb;34(2):156-61. doi: 10.1002/bem.21730.
Abstract
We conducted
a pilot study to assess magnetic field levels in electric compared to
gasoline-powered vehicles, and established a methodology that would provide
valid data for further assessments. The sample consisted of 14 vehicles, all
manufactured between January 2000 and April 2009; 6 were gasoline-powered
vehicles and 8 were electric vehicles of various types. Of the eight models
available, three were represented by a gasoline-powered vehicle and at least
one electric vehicle, enabling intra-model comparisons. Vehicles were driven
over a 16.3 km test route. Each vehicle was equipped with six EMDEX Lite
broadband meters with a 40-1,000 Hz bandwidth programmed to sample every 4 s.
Standard statistical testing was based on the fact that the autocorrelation statistic
damped quickly with time. For seven electric cars, the geometric mean (GM) of
all measurements (N = 18,318) was 0.095 µT with a geometric standard deviation
(GSD) of 2.66, compared to 0.051 µT (N = 9,301; GSD = 2.11) for four
gasoline-powered cars (P < 0.0001). Using the data from a previous exposure
assessment of residential exposure in eight geographic regions in the United
States as a basis for comparison (N = 218), the broadband magnetic fields in
electric vehicles covered the same range as personal exposure levels recorded
in that study. All fields measured in all vehicles were much less than the
exposure limits published by the International Commission on Non-Ionizing
Radiation Protection (ICNIRP) and the Institute of Electrical and Electronics
Engineers (IEEE). Future studies should include larger sample sizes
representative of a greater cross-section of electric-type vehicles.
-- Mythbuster: EMF levels in hybrids Consumer Reports News: August 4, 2010
Summary
“Some concern has been raised about the possible health
effects of electromagnetic field radiation, known as EMF, for people who drive
in hybrid cars. While all electrical devices, from table lamps to copy
machines, emit EMF radiation, the fear is that hybrid cars, with their big
batteries and powerful electric motors, can subject occupants to unhealthy
doses. The problem is that there is no established threshold standard that says
what an unhealthy dose might be, and no concrete, scientific proof that the
sort of EMF produced by electric motors harms people
“We found the highest EMF levels in the Chevrolet Cobalt, a
conventional non-hybrid small sedan.”
[The peak EMF readings at the driver’s feet ranged from 0.5
mG (milligauss) in the 2008 Toyota Highlander to 30 mG in the Chevrolet Cobalt.
The hybrids tested at 2-4 mG. Here are some highlights from the tests. EMF
readings were highest in the driver’s foot well and second-highest at the
waist, much lower higher up, where human organs might be more susceptible to
EMF.
“To get a sense of scale, though, note that users of
personal computers are subject to EMF exposure in the range of 2 to 20 mG,
electric blankets 5 to 30 mG, and a hair dryer 10 to 70 mG, according to an
Australian government compilation. In this country, several states limit EMF
emissions from power lines to 200 mG. However, there are no U.S. standards
specifically governing EMF in cars.”
“In this series of tests, we found no evidence that hybrids
expose drivers to significantly more EMF than do conventional cars. Consider
this myth, busted.”
-- Israel preps world’s first hybrid car radiation scale
Tal Bronfer, the truth about cars, March 1, 2010
Summary
“The Australian Radiation Protection and Nuclear Safety
Agency (ARPANSA) recommends a limit of 1,000 mG (milligauss) for a 24 hour
exposure period. While other guidelines pose similar limits, the International
Agency for Research on Cancer (IARC) deemed extended exposure to electromagnetic
fields stronger than 2 mG to be a “possible cause” for cancer. Israel’s
Ministry of Health recommends a maximum of 4 mG.”
“Last year, Israeli automotive website Walla! Cars conducted
a series of tests on the previous generation Toyota Prius, Honda Insight and
Honda Civic Hybrid, and recorded radiation figures of up to 100 mG during
acceleration. Measurements also peaked when the batteries were either full (and
in use) or empty (and being charged from the engine), while normal driving at
constant speeds yielded 14 to 30 mG on the Prius, depending on the area of the
cabin.
The Ministry of Environmental Protection is expected to
publish the results of the study this week. The study will group hybrids sold
in Israel into three different radiation groups, reports Israel’s Calcalist.
It’s expected that the current-gen Prius will be deemed ‘safe’, while the Honda
Insight and Civic Hybrid (as well as the prev-gen Prius) will be listed as
emitting ‘excessive’ radiation.”
-- Fear, but few facts, on hybrid risk
Jim Motavalli, New York Times, Apr 27, 2008
Summary
“... concern is not without merit; agencies including the National Institutes of Health and the National Cancer Institute acknowledge the
potential hazards of long-term exposure to a strong electromagnetic field, or
E.M.F., and have done studies on the association of cancer risks with living
near high-voltage utility lines. While Americans live with E.M.F.’s all around — produced by
everything from cellphones to electric blankets — there is no broad agreement
over what level of exposure constitutes a health hazard, and there is no
federal standard that sets allowable exposure levels. Government safety tests
do not measure the strength of the fields in vehicles — though Honda and
Toyota, the dominant hybrid makers, say their internal checks assure that their
cars pose no added risk to occupants.” “A spokesman for Honda, Chris Martin, points to the lack of
a federally mandated standard for E.M.F.’s in cars. Despite this, he said,
Honda takes the matter seriously. “All our tests had results that were well
below the commission’s standard,” Mr. Martin said, referring to the European
guidelines. And he cautions about the use of hand-held test equipment. “People
have a valid concern, but they’re measuring radiation using the wrong devices,”
he said.”
“Donald B. Karner, president of Electric Transportation
Applications in Phoenix, who tested E.M.F. levels in battery-electric cars for
the Energy Department in the 1990s, said it was hard to evaluate readings
without knowing how the testing was done. He also said it was a problem to
determine a danger level for low-frequency radiation, in part because dosage is
determined not only by proximity to the source, but by duration of exposure.
“We’re exposed to radio waves from the time we’re born, but there’s a general
belief that there’s so little energy in them that they’re not dangerous,” he
said.”
