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European Foundation of Oncology and Environmental Sciences “B. Ramazzini”
Cesare Maltoni Cancer Research Center
The potential
carcinogenic risks of
electromagnetic fields:
what we know and what
we still must learn
Bologna Summer Event
June 28 2007
Power frequency EMF:
what we know
2
Power frequency EMF: epidemiological evidence

The first epidemiological study of childhood cancer and
EMF was published in 1979.

Since then more than 20 studies have been conducted

The present position on EMF and the epidemiology of
childhood leukemia is summarized in a pooled analysis
of measurement and calculated field studies published by
Ahlbom et al (3247 cases in total).
3
Pooled results from Ahlbom et al
Relative risks (and 95% confidence intervals)
Study
0.1-<0.2 µT
0.2-<0.4 µT
Numbers of subjects
≥ 0.4 µT
≥ 0.4 µT
Observed
Expected
Measurement studies
Canada
Germany
New Zealand
UK
USA
1.29
1.24
0.67
0.84
1.11
1.39
1.67
4 cs/0 ct
0.98
1.01
1.55
2.00
0 cs/0 ct
1.00
3.44
13
2
0
4
17
10.3
0.9
0
4.4
4.7
2.68
0 cs/19 ct
1.75
1.75
0 cs/8 ct
4.11
1.06
0.57
2 cs/0 ct
6.21
0 cs/10 ct
3.74
2
1
0
5
0
0.2
2.7
1.5
Measurements studies
Calculated field studies
1.05 (0.9-1.3)
1.58 (0.8-3.3)
1.15 (0.9-1.5)
0.79 (0.3-2.3)
1.87 (1.1-3.2)
2.13 (0.9-4.9)
36
8
20.1
4.4
All studies
1.08 (0.9-1.3)
1.11 (0.8-1.5)
2.00 (1.3-3.1)
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24.2
Calculated field studies
Denmark
Finland
Norway
Sweden
Summary
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Power frequency EMF: experimental evidence
Authors
Animals
Species/strain
Yasui et al.,
Exposure
Duration
256 males
0; 5 µT
32 weeks
No evidence of
S.D.
per group
(50 Hz)
(22 h/day)
carcinogenic effect
Rats F344
48 females
0;0,5; 5 mT
2 years
No evidence of
(22 h/day)
carcinogenic effect
1997
per group
Mandeville et al., Rats F344
1997
NTP, 1998
Result
No.
Margonato et al., Rats
1995
Treatment
50 males and
(50 Hz)
0; 2; 20; 200;
50 females
2000 µT
per group
(60 Hz)
Rats F344
100 males and
Mice B6C3F1
100 females
0; 2; 200;
1000 µT
2 years, GLP
No evidence of
(20 h/day)
carcinogenic effect
2 years, GLP
Equivocal evidence
(18.5 h/day)
Comments
Only 1 sex (male);
short duration
(32 weeks)
Only 1 sex (male);
short duration
(104 weeks)
Few animals;
short duration
(104 weeks)
Short duration
of carcinogenic effect (104 weeks)
per species and
for thyroid C cell
per group
tumour in male
treated with 2 or
200 µT
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Present position on power frequency EMF (part I)
There is an association between childhood leukemias and
EMF exposure in the study populations.
However, it is not yet possible to establish a causecorrelation for two reasons:
1) the absence of a plausible mechanism
2) lack of support from laboratory evidence
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Present position on power frequency EMF (part II)

These factors led IARC to classify power frequency
EMF as a possible carcinogen in 2001

Were there an accepted mechanism of action or
robust supporting evidence from the laboratory, it is
probable that EMF would have instead been
classified as an established carcinogenic agent.
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Radio frequency EMF
(RFEMF):
what we know
8
RFEMF: epidemiological evidence (part I)
1978-1995: Various epidemiological studies conducted
on military personnel exposed to radar waves and on
children living near radio-television aerials indicate a
possible increase in limphomas/leukaemia
2001-2002: Initial epidemiological data on tumours of
acustic nerves have been reassuringly negative
9
RFEMF: epidemiological evidence (part II)
2004: Preliminary results of an epidemiological study
condicted in Sweden report an increase in tumours of
the acustic nerve in population exposed to cellular
telephones (RFEMF) (Ahlbom, 2004)
2006: Pooled analysis of two case-control studies on
use of cellular and cordless telephones showed an
increase risk of malignant brain-tumours diagnosed in
1997-2003, highest in the group with > 10 years
latency period
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RFEMF: experimental evidence
Authors
Animals
Species/strain No.
Chou et al.,
1992
Rats
S.D.
Repacholi et al.,Mice
Em-Pim1
1997
100 males
per group
100 females
per group
Utteridge et al.,Mice
120 females
Em-Pim1;
w.t.
2002
per group
Bartsch et al., Rats
S.D.
2002
60 females
per group
Treatment
Exposure
Result
Comments
Duration
25 months Excess of primary Only 1 sex (male);
(2,450MHz) (21.5 h/day) malignant tumors short duration
(110 weeks)
(900 MHz)
(900 MHz)
18 months Increase risk of
(1h/day) lymphomas
2 years
(1h/day)
Only 1 sex (female);
short duration
(78 weeks)
Only 1 sex (male);
No evidence of
carcinogenic effect short duration
(104 weeks)
(900 MHz
(23 h/day) No evidence of
and DMBA)
carcinogenic
effect for
mammary
tumors
Few animals
short duration
(sacrificed within
1 year)
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Present position on RFEMF
 Use of cell phones for < 10 years have not
demonstrated an increase in cancer
 There is however some evidence regarding longterm use and lengthy latency period
absence of evidence ≠
absence of risk
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EMF and RFEMF:
what we still must learn
13
Diffused carcinogenic risks
EMF and RFEMF represent what are known as
diffused carcinogenic risks.
We use this term to describe carcinogenic risks of
low potency, but to which almost the entire
population of the planet may be exposed.
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Examples of diffused carcinogenic risks
1) agents which are slightly carcinogenic at
any dose;
2) low or extremely low doses of strong
carcinogenic agents;
3) mixtures of small doses of any carcinogenic
agents.
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Tools for identifying diffused carcinogenic risks
In the case of diffused carcinogenic risks,
it is not sufficient to follow the standard
protocol used in ordinary experiments,
but rather it is necessary to conduct what
we define as mega-experiments.
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Characteristics of mega-experiments

reproduce the various conditions of human exposure

use vast numbers of animals per group, in order to
express variations in the effects more sharply

are conducted until the natural death of the rodents,
to allow an agent to express its full carcinogenic
potential

evaluate all neoplastic and non-neoplastic
pathologies
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35 years of mega-experiments at the ERF
agent
# rodents
vinyl chloride
> 7,000
vitamins
> 8,000
coca-cola
> 2,000
gamma radiation
> 10,000
irradiated food
> 2,000
electromagnetic fields
> 9,000
extremely low frequency
> 7,000
radiofrequency
> 2,000
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Integrated project of the
European Ramazzini
Foundation (ERF)
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ERF mega-experiments to evaluate EMF (50Hz)
Experiment
Age at start
Number of animals
(M+F)
Treatment
Duration
BT 1 CEM
embryo
5,029
50Hz-magnetic field
Lifespan
BT 2 CEM
embryo
805
50Hz-magnetic field
and formaldehyde
Lifespan
BT 3 CEM
embryo
657
50Hz-magnetic field
and 10 gamma rads
Lifespan
BT 4 CEM
embryo
642
50Hz-magnetic field
and aflatoxin B1
Lifespan
TOTAL
7,133
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ERF mega-experiment on EMF (50Hz)
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ERF mega-experiment to evaluate RFERF (1.8 GHz)
Experiment BT 1 CEMRF
Group number
Age at start
Number of animals
(M+F)
Treatment (Volt/meter)
Duration
I
embryo
409
50 Volt/meter
Lifespan
II
embryo
411
25 Volt/meter
Lifespan
III
embryo
811
5 Volt/meter
Lifespan
IV
embryo
817
0 Volt/meter (control)
Lifespan
TOTAL
2,448
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ERF mega-experiment on RFEMF (1.8 GHz)
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Conclusions

The epidemiological evidence concerning EMF and longterm exposure to RFEMF show there are reasonable
grounds for concern for the possibility of adverse effects

The absence of epidemiological evidence concerning
short-term exposure RFEMF ≠ the absence of risk

While we await the results of the experiments currently
underway (2009-2011), the precautionary principle
guides us to “undertake provisional risk management
measures…without having to wait until the reality and
seriousness of those adverse effects become fully
apparent”
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