Carcinogenicity of Radiofrequency
Electromagnetic Fields (EMF)
2015: the US National Institutes of Health (NIH), exposed rats and mice to
non-ionising radio-frequency radiation ( 2g and 3G not 4G) like that emitted by
phones. Some of the exposed animal groups did have a higher incidence of damage
to the heart, and cancers in nerves to the heart.
But the animals were given much higher doses of radiation than people experience
in real life – even those of us who are glued to our phones. They were kept in
special chambers that exposed them to high levels of radiation over their whole
body, for nine hours a day over the duration of their two-year lives. So the
findings cannot be assumed to also apply to humans, NIH researcher John Bucher
said in a statement.
No good evidence
More importantly, there has been no good evidence that cancers of these types
are increasing in people. Our use of mobile phones and other wireless devices in
our homes has been increasing at an unprecedented rate. Cancer incidence is
tracked carefully in countries such as the UK and the US – if tumours of the
heart or brain were on the rise, we would know about it by now.
SOURCE
Robert Baan a,
Yann Grosse a,
Béatrice Lauby-Secretan a,
Fatiha El Ghissassi a,
Véronique Bouvard a,
Lamia Benbrahim-Tallaa a,
Neela Guha a,
Farhad Islami a,
Laurent Galichet a,
Kurt Straif a, on behalf
of the WHO International Agency for Research on Cancer Monograph Working Group
In May, 2011, 30 scientists from 14 countries met at the International
Agency for Research on Cancer (IARC) in Lyon, France, to assess the
carcinogenicity of radiofrequency electromagnetic fields (RF-EMF). These
assessments are published as Volume 102 of the
IARC
Monographs. 1
It
appears that the number of incidences of glioma does not
correlate to the large increase in cellphone use over time.
IARC on the
Evaluation of Carcinogenic Risks to Humans
Non-Ionizing Radiation, Part 2: Radiofrequency Electromagnetic Fields
(2013)
6.
EVALUATION
6.1
Cancer in humans
There is limited evidence in humans for the
carcinogenicity of radiofrequency radiation.
Positive associations have been observed
between exposure to radiofrequency radiation from wire-less phones
and glioma, and acoustic neuroma.
6.2
Cancer in experimental animals
There is limited evidence in experimental
animals for the carcinogenicity of radio frequency radiation.
|
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New York Times: “If phones are linked to cancer, we’d expect to
see a marked uptick,” David Robert Grimes, a cancer researcher at the
University of Oxford,
wrote recently in The Guardian. “Yet we do not.”
No, a rat study with marginal results does not prove that cell phones
cause cancer, no matter what Mother Jones and Consumer Reports say.
EMF,
Electromagnetic Fields for Electrical Workers Show No Brain Tumor Risk
2018
The FACTS on EMF & SMART METERS
It is worth mentioning that the 3G and
4G mobile phones commercially available today – equipped with adaptive
power control – emit considerably less RF energy
than the GSM phones used more than a decade ago. The key
epidemiological studies were conducted in the
late 1990s and the early 2000.
The Working Group agreed to consider three categories of human
exposure to RF radiation:
 | 1. environmental sources such as mobile-phone
base stations, broadcast antennae, smart meters, and medical
applications; |
| 2. occupational sources such as high-frequency
dielectric and induction heaters, and high-power pulsed radars; and
|
| 3. the use of personal devices such as
mobile phones |
|
6.3 Overall evaluation
Radiofrequency electromagnetic fields are possibly
carcinogenic to humans (Group 2B).
6.4 Rationale for the
evaluation of the epidemiological evidence
The human epidemiological evidence was mixed.
Several small early case–control studies were considered to be largely
uninformative.
A large cohort study showed no increase in risk of
relevant tumours, but it lacked information on level of mobile-phone use
and there were several potential sources of misclassification of
expo-sure.
The bulk of evidence came from reports of the
INTERPHONE study, a very large inter-national, multicentre case–control
study and a separate large case–control study from Sweden on
gliomas
and
meningiomas
of the brain and
acoustic
neuromas.
While affected by
selection bias and information bias to varying degrees, these
studies showed an association between
glioma and acoustic neuroma and
mobile-phone use; specifically in
people:-
|
With highest cumulative use of mobile phones, |
|
who had used mobile phones
on the same side of the head as that on which their tumour developed,
and |
|
whose tumour was in the temporal lobe of the brain (the area of the brain that is most exposed to
RF radiation when a wireless phone is used at the ear). |
The Swedish study found similar results for
cordless phones. The comparative weakness of the associations in the
INTERPHONE study and inconsistencies between its results and those of
the Swedish study led to the evaluation of limited evidence for
glioma and acoustic neuroma, as decided by the majority of
the members of the Working Group.
A small, recently published Japanese case–control
study, which also observed an association of acoustic neuroma
with mobile-phone use, contributed to the evaluation of limited evidence
for acoustic neuroma.
There was, however, a minority opinion that
current evidence in humans was inadequate, therefore permitting no
conclusion about a causal association. This minority saw inconsistency
between the two case–control studies and a lack of exposure–response
relationship in the INTERPHONE study.
The minority also pointed to the fact that no
increase in rates of glioma or acoustic neuroma was seen
in a nation-wide Danish cohort study, and that up to now, reported time trends in
incidence rates of glioma have not
shown a trend parallel to time trends in mobile-phone use.
SOURCE:
http://monographs.iarc.fr/ENG/Monographs/vol102/index.php
http://monographs.iarc.fr/ENG/Monographs/vol102/mono102-005-006.pdf
http://marincounty.info/Healthcare/carcinogenicity_of_phones_radiofrequenc.htm
http://marincounty.info/Healthcare/SMART_METERS.htm
Volume 80 (Static and
Extremely Low-Frequency (ELF) Electric and Magnetic Fields; IARC,
2002), and the fourth and last in a series on physical agents, after
Volume 75
(Ionizing Radiation, Part 1: X- and Gamma-radiation, and Neutrons;
IARC, 2000) and
Volume 78
(Ionizing Radiation, Part 2: Some Internally Deposited Radionuclides;
IARC, 2001).
Solar radiation and ultraviolet
radiation were evaluated in Volume 55 (IARC, 1992).
The types of radiation evaluated
as human carcinogens (Group 1) were revisited in
Volume 100D
(IARC, 2012). A summary of the findings in the present volume has
appeared in The Lancet Oncology(Baan et al., 2 011)
The FACTS on SMART METERS
Human exposures to RF-EMF (frequency
range 30 kHz to 300 GHz) can occur :-
from use of personal devices (eg,
| mobile telephones, |
| cordless phones, |
| Bluetooth, and amateur radios |
from occupational sources (eg,
| high-frequency dielectric and induction heaters, and |
| high-powered pulsed radars), |
and from environmental sources such as
| mobile-phone base stations, |
| broadcast antennas, and |
| medical applications. |
|
|
For workers, most exposure to RF-EMF comes from
near-field sources, whereas the general population receives
the highest exposure from transmitters close
to the body, such as handheld devices like mobile telephones.
Exposure to high-power sources at work might involve higher
cumulative RF energy deposited into the body than exposure to mobile
phones, but the local energy deposited in the brain is generally
less.
Typical exposures to the
brain from rooftop or tower-mounted mobile-phone base
stations and from TV and radio stations are several orders of
magnitude lower than those from global system for mobile
communications (GSM) handsets. The
average exposure from use of digital enhanced cordless
telecommunications (DECT) phones is
around five times lower than that measured for
GSM phones, and third-generation (3G)
phones emit, on average, about 100 times less RF energy than
GSM phones,
when signals are strong. Similarly, the average output power of
Bluetooth wireless hands-free kits is
estimated to be around 100 times lower than that of mobile
phones.
EMFs generated by RF sources couple with the body, resulting in
induced electric and magnetic fields and associated currents inside
tissues. The most important factors
that determine the induced fields are the
distance of the source from the body and the output power level.
Additionally, the efficiency of coupling and resulting
field distribution inside the body strongly depend on the frequency,
polarisation, and direction of wave incidence on the body, and
anatomical features of the exposed person, including height,
body-mass index, posture, and dielectric properties of the tissues.
Induced fields within the body are highly non-uniform, varying over
several orders of magnitude, with local hotspots.
|
| |
|
|
Holding a mobile phone to the ear to make a voice call can result in high specific RF energy
absorption-rate (SAR) values in the brain,
depending on the design and position of the phone and its antenna in
relation to the head, how the phone is held, the anatomy of the head, and
the quality of the link between the base station and
phone. When used by children, the
average RF energy deposition is two times higher in the
brain and up to ten times higher in the bone
marrow of the skull, compared with mobile phone use by adults.2 Use of hands-free kits lowers
exposure to the brain to below 10% of the exposure from use at the ear,
but it might increase exposure to other parts of the body.3
Epidemiological evidence for an association between
RF-EMF and cancer comes from cohort,
case-control, and time-trend studies. The populations in these studies
were exposed to RF-EMF in occupational
settings, from sources in the general environment,
and from use of wireless (mobile and cordless)
telephones, which is the most extensively studied exposure source.
One cohort study4
and five case-control studies5—9 were judged by the Working Group
to offer potentially useful information regarding associations between use
of wireless phones and
glioma. The cohort study4
included 257 cases of glioma among 420 095 subscribers to two Danish
mobile phone companies between 1982 and 1995.
Glioma incidence was
near the national average for the subscribers. In this study,
reliance on subscription to a mobile phone provider, as a surrogate for
mobile phone use, could have resulted in
considerable misclassification in exposure
assessment. Three early case-control studies5—7 encompassed a period when mobile
phone use was low, users typically had low
cumulative exposures, time since first use of a mobile
phone was short, and effect estimates were
generally imprecise; the Working Group considered these studies less informative. Time-trend analyses
did not show an increased rate of brain
tumours after the increase in mobile phone
use. However, these studies have substantial limitations because most of
the analyses examined trends until the early 2000s only. Such analyses are
uninformative if excess risk only manifests more than a decade after
phone use begins, or if
phone use only affects a small proportion of cases—eg, the most
heavily exposed, or a subset of brain
tumours.
The INTERPHONE study,8
a multicentre case-control study, is the largest investigation so far of
mobile phone use and
brain tumours, including glioma,
acoustic neuroma,
and meningioma. The pooled analysis included
2708 glioma cases and 2972 controls
(participation rates 64% and 53%, respectively). Comparing those who ever
used mobile phones with those who never did
yielded an odds ratio (OR) of 0·81 (95% CI 0·70—0·94). In terms of
cumulative call time, ORs were uniformly below or close to unity for all
deciles of exposure except the highest decile (>1640 h of use), for which
the OR for glioma was 1·40 (95% CI 1·03—1·89). There was suggestion of an
increased risk for ipsilateral exposure (on the same side of the head as
the tumour) and for tumours in the temporal
lobe, where RF exposure is highest. Associations between
glioma and cumulative specific energy
absorbed at the tumour location were examined in a subset of 553 cases
that had estimated RF doses.10
The OR for glioma increased with increasing
RF dose for exposures 7 years or more before diagnosis, whereas there was
no association with estimated dose for exposures less than 7 years before
diagnosis.
A Swedish research group did a pooled analysis of two very similar studies
of associations between mobile and cordless phone
use and glioma, acoustic
neuroma, and meningioma.9
The analysis included 1148 glioma cases
(ascertained 1997—2003) and 2438 controls, obtained through cancer and
population registries, respectively. Self-administered mailed
questionnaires were followed by telephone interviews to obtain information
on the exposures and covariates of interest, including use of mobile and
cordless phones (response rates 85% and 84%,
respectively). Participants who had used a mobile
phone for more than 1 year had an OR for
glioma of 1·3 (95% CI 1·1—1·6). The OR increased with increasing
time since first use and with total call time, reaching 3·2 (2·0—5·1) for
more than 2000 h of use. Ipsilateral use of the mobile
phone was associated with higher risk.
Similar findings were reported for use of cordless
phones.
Although both the INTERPHONE study and the
Swedish pooled analysis are susceptible to
bias—due to recall error and selection for participation—the Working Group
concluded that the findings could not be dismissed as reflecting bias
alone, and that a causal interpretation between mobile
phone RF-EMF exposure and
glioma is possible. A similar conclusion was
drawn from these two studies for acoustic neuroma, although the case
numbers were substantially smaller than for glioma.
Additionally, a study from Japan11
found some evidence of an increased risk for
acoustic neuroma associated with ipsilateral mobile
phone use. For
meningioma, parotid-gland tumours, leukaemia,
lymphoma, and other tumour types, the Working
Group found the available evidence insufficient to
reach a conclusion on the potential association with mobile phone
use.
Epidemiological studies of individuals with potential occupational
exposure to RF-EMF have investigated brain tumours,
leukaemia, lymphoma,
and other types of malignancy including uveal
melanoma, and cancers of the testis,
breast, lung, and skin. The Working Group noted that the studies had
methodological limitations and the results were inconsistent. In reviewing
studies that addressed the possible association between environmental
exposure to RF-EMF and cancer, the Working
Group found the available evidence insufficient for
any conclusion.
The Working Group concluded that there is “limited
evidence in humans” for the carcinogenicity of RF-EMF, based on positive
associations between glioma and acoustic neuroma and exposure to RF-EMF
from wireless phones. A few members of the Working Group considered
the current evidence in humans “inadequate”. In their opinion there was
inconsistency between the two case-control studies and a lack of an
exposure-response relationship in the INTERPHONE
study results; no increase in rates of glioma
or acoustic neuroma was seen in the
Danish cohort study,4
and up to now, reported time trends in incidence
rates of glioma have not shown a parallel to temporal trends in mobile
phone use.
The Working Group reviewed more than 40 studies that
assessed the carcinogenicity of
RF-EMF in rodents,
including seven 2-year cancer bioassays. Exposures included 2450 MHz
RF-EMF and various RF-EMF that simulated emissions from mobile
phones. None of the chronic bioassays showed
an increased incidence of any tumour type in tissues or organs of animals
exposed to RF-EMF for 2 years. An increased total number of malignant
tumours was found in RF-EMF-exposed animals in one of the seven chronic
bioassays. Increased cancer incidence in
exposed animals was noted in two of 12 studies with tumour-prone animals12,
13 and in one of 18 studies using
initiation-promotion protocols.14
Four of six co-carcinogenesis studies showed increased cancer incidence
after exposure to RF-EMF in combination with a known
carcinogen; however, the predictive value of this type of study for
human cancer is unknown. Overall, the Working
Group concluded that there is “limited evidence” in
experimental animals for the carcinogenicity of RF-EMF.
The Working Group also reviewed many studies with endpoints
relevant to mechanisms of carcinogenesis,
including genotoxicity, effects on immune function,
gene and protein expression, cell signalling, oxidative stress, and
apoptosis. Studies of the possible effects of RF-EMF on the
blood-brain barrier and on a variety of
effects in the brain were also considered.
Although there was evidence of an effect of RF-EMF on some of these
endpoints, the Working Group reached the overall
conclusion that these results provided only weak mechanistic evidence
relevant to RF-EMF-induced cancer in humans.
In view of the limited evidence in humans and in
experimental animals, the Working Group classified
RF-EMF as “possibly carcinogenic to humans”
(Group 2B). This evaluation was supported by a large majority of
Working Group members.
The Risk, if Any, Is Not Great Enough
By Larry Junck (Wall St Journal article May 2016)
Each year, about 78,000 Americans are diagnosed with a malignant or benign
brain tumor. These lead to about 17,000 deaths—seventh among deaths due to
cancer. As a physician kept busy caring for people with brain tumors, I would
like nothing more than to see some of these tumors prevented.
Unfortunately, a label warning purchasers of
cellphones about an unproven brain-tumor risk would
not be a step toward that goal.
Consider that brain tumors have not increased in
incidence in correlation with
cellphone use. If
cellphones were an important cause of brain tumors,
we would have seen an increase perhaps starting in the 1990s, when
cellphones came into widespread use, or starting
several years later, if it took several years of
cellphone use to cause a brain tumor. While the
number of people diagnosed with brain tumors has risen, the increase has been
mainly among the elderly, who use
cellphones less than others. The increase started
before the 1990s, and the numbers have leveled off. The
increase is believed to be largely due to our improved
detection of brain tumors using CT scans and MRI.
Also, there is no known scientific mechanism by which mobile phones might
cause brain tumors. For carcinogenic chemicals and other environmental causes of
cancer, we can generally show that these cause mutations in DNA or changes in
other molecules, sufficient to explain the resulting cancers. However, radiofrequency emissions such as those emitted by
cellphones generally pass through tissues
without causing these effects.
Numerous epidemiologic studies considered together do not conclusively show
an increase in risk of brain tumors associated with
cellphone use. The majority of studies show no
association at all. A number of studies do suggest an increase in risk, but some
of these studies depend on patients’ recall of their
cellphone usage and thus are susceptible to bias.
One of the largest studies,
the
Interphone study done in 13 countries and
published in 2010, showed no increase in risk in
its primary analysis. A widely criticized secondary
analysis showed that among the 10% of
subjects who recalled the highest usage, incidence of glioma (the most common of
serious brain tumors) was increased by 40%—of marginal significance due to the
small number of tumors in the secondary analysis. Based largely on this study,
WHO’s International Agency for Research on Cancer
classified radio-frequency electromagnetic fields as “possibly carcinogenic” in
humans, a category that includes coffee and
pickled vegetables. Many
experts have expressed opinions
disagreeing with this classification because of the lack of good
evidence supporting it.
Other conceivable risks of RF have also been studied. An example is effects
on sperm. A meta-analysis of many studies looking for an association of
cellphone use with changes in sperm reported that
one of three variables studied, sperm motility, shows a small but statistically
significant relationship. But the authors do not indicate how sperm development
might be affected by RF from
cellphones, considering that RF emissions are
concentrated near their source and that
cellphones are generally held far from the scrotum
while in use.
Most scientific organizations that have studied this issue, such as the
World Health Organization and the
National Cancer Institute, find no convincing
evidence of risk of brain tumors or other harms. The Food
and Drug Administration states, “The weight of scientific evidence has
not linked
cellphones with any health problems.”
Meanwhile, supporters of stronger warnings point to reports in the
insurance industry citing the possibility of
increased liability to claims of health damage from
cellphones, but such conclusions appear to be based
on ` arising from public concerns that are not
based on evidence of harm. I submit that public policy should be based on actual
risk, not on popular perceptions that aren’t supported by evidence.
Do risks of
cellphones require more study? Yes, especially
looking for any long-term risk to children who use them extensively over many
years. Meanwhile, there is not much basis for modifying our use of mobile phones
because of the risk of brain tumors or other risks from RF emissions.
If a risk exists at all, it is not high enough to justify a warning label for
consumers. Warning labels are best reserved for risks that are both more
clear-cut and larger. Perhaps use of
cellphones while driving is an example.
Dr. Junck is professor of neurology at the University of Michigan Health
System. He can be reached at reports@wsj.com.
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