The World Health Organization concludes there is “limited
evidence” in both humans and laboratory animals for the carcinogenicity of
radiofrequency radiation, especially from cell phones.
The
International Agency for Research on Cancer (IARC) of the World Health
Organization (WHO) published its long-awaited monograph on the cancer risk to
humans from exposure to cell phone radiation and other radiofrequency electromagnetic
fields. The primary focus of the review is on the microwave radiation emitted
by cell phones.
According to the
monograph, “Radiofrequency electromagnetic fields are possibly
carcinogenic to humans (Group 2B).” (p. 421) Children are particularly vulnerable to this carcinogenic effect as “the
average exposure from use of the same mobile phone is higher by a factor of 2
in a child’s brain and higher by a factor of 10 in the bone marrow of the skull.”
Also, the child’s brain is developing at a greater rate than the adult
brain.
This 471 page report
is based on the consensus of a Working Group of 31 international experts who met
in Lyon, France in May, 2011. Although a few studies published since this
meeting were included in this monograph, other recent studies that further
support the evidence for increased cancer risk due to exposure to cell phone radiation
were not reviewed.
The monograph
only examines research on cancer risk. Other research has found that cell phone
radiation has additional harmful effects on humans, especially on sperm and the
fetus.
Following are
what I consider to be the most important quotes from the monograph. I highlighted
some phrases with boldface type.
From IARC's "Note to the Reader"
"The
term ‘carcinogenic risk’ in the IARC Monographs series is taken to mean that an
agent is capable of causing cancer...identification of cancer sites with
sufficient evidence or limited evidence in humans should not be viewed as
precluding the possibility that an agent may cause cancer at other sites. The
evaluations of carcinogenic risk are made by international working groups of
independent scientists and are qualitative in nature. No recommendation is
given for regulation or legislation.”
Exposure Data
“While the
number of mobile-phone subscriptions has been increasing rapidly around the world
(4.6 billion subscribers in 2009), changes in mobile-phone technology have led
to lower time-averaged RF power emitted from mobile phones used at present than
those of previous generations. Of major
interest to this Monograph
is the exposure
scenario in which mobile phones are held against the ear during a voice call.”
(p. 407)
“GSM 900/1800/PCS phones (Global System
for Mobile communications/Personal Communications Service, operating at 900 or 1800
MHz) held next to the ear induce high spatial-averaged
SAR values in the brain. This is because adaptive power control on average only
reduces the output power to about 50% of its maximum during calls, but this
would vary depending on the network software.” (p. 408) [SAR or Specific
Absorption Rate is a measure of the maximum amount of radiation absorbed in the
brain from a cell phone or cordless phone, averaged over a specific volume of
tissue for a specific period of time.]
“Adaptive power
control is much more effective with third-generation (3G) phone technologies,
and this has led to a reduction of SAR in the brain by almost two orders of
magnitude compared with that from GSM phones. The DECT (Digital Enhanced
Cordless Telecommunications) phone is another widely used device that is held against
the ear to make and receive voice calls. The average SAR in the brain from use
of DECT phones is around five times lower than that measured for GSM phones … The
spatial maximum exposure from cordless DECT phones is an order of a magnitude lower
than that from mobile phones.” (p. 408) [DECT phone technology is used in
cordless phones used in homes and offices.]
“Due to the closer proximity of the phone to the brain of
children compared with adults, the average exposure from use of the same mobile
phone is higher by a factor of 2 in a child’s brain and higher by a factor of
10 in the bone marrow of the skull.” (p. 408)
INTERPHONE Study
“In terms of
cumulative call time, all odds ratios were uniformly below unity for all
deciles of exposure except for the highest decile (≥ 1640 hours of cumulative
call time). For this exposure group, the odds ratio for glioma was 1.40 (95% CI,
1.03–1.89). Some other analyses of the same data also pointed to a possible
association of mobile-phone use with risk of glioma, including the findings
related to location of tumour (a higher odds ratio for tumours in the temporal lobe)
and laterality of mobile-phone use (an apparently higher odds ratio in those
who used a mobile phone on the same side of the head as the tumour). In an
attempt to obviate the distortions that might have been generated by
differential non-participation, an analysis was conducted with the lowest
exposure decile as the reference; this showed a high odds ratio in the highest
exposure decile.” (p. 411)
“In summary, in
the INTERPHONE study there was no increased risk of glioma associated with
having ever been a regular user of mobile phones. However, there were
indications of an increased risk of glioma at the highest levels of cumulative
call time, for ipsilateral exposures, and for tumours in the temporal lobe, but
chance or bias may explain this increased risk.” (p. 411)
Swedish Studies
“When mobile phone
users were compared with people who reported no use of mobile or cordless
phones, or exposure > 1 year before the reference date, an increased odds
ratio was estimated (OR, 1.3; 95% CI, 1.1–1.6). The odds ratios increased
progressively with increasing time since first mobile phone use, and with
increasing cumulative call time for the ordered categories of exposure duration
(1–1000, 1001–2000, and > 2000 hours) as follows: 1.2 (95% CI, 0.98–1.4),
1.5 (95% CI, 1.1–2.1), and 2.5 (95% CI, 1.8–3.5), respectively. Ipsilateral use
of the mobile phone was associated with higher risk. Further, there were
similar findings in relation to the use of cordless phones.” (p. 411)
Comparison of INTERPHONE and Swedish Studies
“Overall, the
Working Group reviewed all the available evidence with regard to the use of
wireless phones, including both mobile and cordless phones, and the risk of glioma. Time trends were considered, as
were several early case–control studies and one cohort study. The evidence from
these studies was considered less informative than the results of the
INTERPHONE study and the Swedish case–control study. While both of these are susceptible to bias, the Working Group
concluded that these findings could not be dismissed as reflecting bias alone,
and that a causal interpretation was possible.”
“In considering
the evidence on acoustic neuroma, the Working Group considered the same
methodological concerns as for glioma, but concluded that bias was not
sufficient to explain the positive findings, particularly those of the study
from Sweden.” (p. 412) [My note: positive findings refers to increased tumor
risk]
“For meningioma, the same two studies mentioned
above provided the key evidence. Overall, in each, the findings generally
indicated no increase in risk.” (p.
412)
“The Working Group
found the evidence to be insufficient to reach a conclusion as
to the potential association of mobile-phone use and either leukaemia or lymphoma.” (p. 412)
“Evidence to date does not point to a causal
association of mobile-phone use with the various additional malignancies
addressed, including ocular or cutaneous melanoma, cancer of the testis, cancer
of the breast, or tumours of the parotid gland.” (p. 412)
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 wireless phones
and glioma, and acoustic neuroma.” (p. 421)
Cancer
in Experimental Animals
“There is limited evidence in experimental animals
for the carcinogenicity of radiofrequency radiation.” (p. 412)
Overall Evaluation
“Radiofrequency
electromagnetic fields are possibly carcinogenic to humans (Group
2B).” (p. 421)
“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.” (p. 421)
Reference
Non-ionizing
radiation, Part II: Radiofrequency electromagnetic fields / IARC Working Group
on the Evaluation of Carcinogenic Risks to Humans (2011: Lyon, France). Vol. 102 (2013).
The complete monograph can be downloaded from the IARC web site:
