Transcript Slide 1

What the History of Epidemiology
and Toxicology Teach Us
About Understanding
Cell Phone Risks
Devra Davis, Ph.D. MPH
Porto Allegre, Brasil
May 19,2009
Caveat Emptor
International Congress
of Scientific and Social
Campaign Against
Cancer held in Brussels
in 1936
Known Cancer Causes -Chapterof2Scientific and
International Congress
Social Campaign Against Cancer, 1936
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Hormones
X-Radiation
Solar radiation
Coal tars/ soots
Benzene
Cobalt-uranium mining
Clarence Cook Little
headed the American
Cancer Society until 1954,
when the geneticist
became the founding
Director of the Scientific
Advisory Board of the
Tobacco Industry
Research Council.
Chapter 7: Saving Cigarettes
The Secret Ingredient in Kent
Cigarettes???
Crocidolite Asbestos
Cell Phone Science
Follows Tobacco Playbook
• Raise doubts about experimental
findings
• Fund and develop studies
• “War Gaming” of challenging results
Changing Cell Phone Patterns
phones per 1000 users
Region
1990
2000
2005
US
127
683
946
Western
Europe
Asia
60
930
1008
7.1
230
379
World
2.1
123
319
Use among 1,600 13-to-15-year-olds in
Belgium, Katholieke University Leuven
• almost 60% of students (ages 13-15) used
cell phones to talk or text message after
turning their lights out at bedtime.
• teens who used their cell phone more than
once a week after lights-out were five times
more likely than those who never did so to
indicate fatigue and sleep difficulties.
Cell Signals Penetrate the Brains
of Children More than Adults
With Permission of Om P. Gandhi
[Gandhi and Kang, 2002]
SAR in plane of antenna feed point
Adult
10 year old
5 year old
Bit-Babik et al. “Simulation of Exposure and SAR Estimation for Adult and Child
Heads Exposed to RF Energy from Portable Communication Devices”
Radiation Research 163, 580-590 (2005)
French Telecom Estimate of Differential
Absorption of Radiofrequency with Age
Wiart et al Phys Med Biol 2008;53:368
Marketing Cell Phones
For Children
glowPhone Gift Package
glowPhone everything active kids and parents
need to keep in touch during their increasingly
busy days.
The glowPhone features a full color screen,
built in games, customizable ringtones and wallpapers
also has a flashlight.
$74.98
Show Color:
Marketing to Five Year Olds
Pew Center Estimates on Children’s
cell phone patterns
• 63% of teenagers age 12-17 have cell phones
• Girls age 15-17 most likely to have them (79 percent).
• 55% of teens with cell phones use them to talk daily.
60% of teens with cell phones send text messages daily.
54% of kids age 8-12 are expected to have a cell phone in
the next three years.
Sources: Pew Internet & American Life Project report “Teens and Social Media”
and the Center on Media and Child Health, 2008
Changing Use of Cell Phones
in U.S. Children/Young Adults
2008
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20% of seven year olds
40-60% of middle school children
Changing use patterns
The average cell phone call in 2003 lasted
2.87 minutes, and the average monthly bill
was $49.91.
• Growing marketing to children
Changing Patterns of Cell Phone
Use in Teenagers
• No students had their own mobile phones
20 years ago
• 2008 more than three-fourths of all teens
age 15-17 possess cell phones
Special Packaging for Children
Cell phone use among
children
Children are a sensitive population:
For most tumors and a large number of carcinogens there is an
inverse association between age at exposure and development of
the disease.
Children can experience a long latency period between exposure
and development of the disease.
Sadetzki, 2009
MOBI-KIDS
“Risk of brain cancer from exposure to radiofrequency fields
in childhood and adolescence”
[Collaborative Project of the Seventh Framework Programme
Theme Environment (including climate change) – 2009-2014]
Childhood brain cancer from exposure to
radiofrequency fields in childhood and adolescence
• Collaborative Project.
• EC grant – topic of call: Health impacts of
exposure to RF fields in childhood and
adolescence (ENV.2008.1.2.1.1.)
FRANCE, DECEMBER 2008
(Vriheid M, Occup Environ Med 2006)
Detailed data on cell
phone use (duration &
frequency of calls, side of
use, use while moving, use
of handset and handheld
devices, use in urban &
rural areas)
r=0.7
“Based on the largest number of benign PGT
patients reported to date, our results suggest an
association between cellular phone use and PGTs”.
This research was funded by The Israel Cancer Association
Cellular phone use & the risk of benign &
malignant Parotid Gland Tumors – a
nationwide case-control study
Consistent elevated risks were shown in complementary analyses
restricted to conditions that may yield higher levels of exposure:
After 5 y of cellphone use, an increase of 34% was observed in
the risk to develop a tumor, in the same side of the head where
the cell phone was held.
For ipsilateral use, an excess risk of about 50% was observed in
the highest category of use.
An excess risk was found among cell phones heavy users in rural
areas characterized by a relatively small number of antennas.
(Sadetzki
S, Am J Epidemiol 2008)
INTERPHONE study:
% of cellphone heavy users (upper quintile) by center
Cumulative Call Time (%)
40
35
Sadetzki
30
Interphone
upper
quintile=735h
25
20
Israel upper
quintile=1324h
15
10
5
er
m
an
y
ly
G
Ita
Fr
an
ce
ay
N
or
w
ed
en
Sw
an
ad
a
C
Ja
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ar
k
en
m
D
Fi
nl
an
d
N
Z
al
ia
A
45
us
tr
Is
ra
el
50
40
35
30
25
Interphone
upper
quintile=12800
20
15
10
5
er
m
an
y
G
Fr
an
ce
ly
Ita
ar
k
D
en
m
K
U
ay
or
w
N
ed
en
Sw
Ja
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an
ad
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Z
N
Fi
nl
an
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A
us
tr
al
ia
0
Is
ra
el
Cumulative Number of Calls (%)
0
Israel upper
quintile=25328
calls
Hardell metanalysis, 2008
Table 2. Odds ratios (ORs) and 95 % confidence intervals (CIs) from six case-control studies on glioma incl
studies using > 10 years latency period. Numbers of exposed cases and controls are given.
Study
Author, year of publication,
country, latency, reference
number
Lönn et al 2005, Sweden,
> 10 years (14)*
Christensen et al 2005,
Denmark, low-grade glioma,
> 10 years (15)*
Christensen et al 2005,
Denmark, high-grade glioma,
> 10 years (15)*
Hepworth et al 2006, UK,
> 10 years (16)*
Schüz et al 2006, Germany,
> 10 years (17)
Hardell et al 2006, Sweden,
> 10 years (1), all glioma
-Low-grade glioma
-High-grade glioma
Lahkola et al 2006, Denmark,
Norway, Finland, Sweden,
UK, > 10 years (18)
Meta-analysis
Total
No. of OR
cases/controls
95 %
CI
Ipsilateral
No. of OR
cases/controls
95 % CI
cases/c
25/38
0.9 0.5 – 1.5
15/18
1.6
0.8 – 3.4
6/9
1.6 0.4 – 6.1
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-
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8/22
0.5 0.2 – 1.3
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-
-
66/112
0.9 0.6 – 1.3
1.6
0.9 – 2.8
12/11
2.2 0.9 – 5.1
Not
given
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-
78/99
2.7 1.8 – 3.9
41/28
4.4
2.5 – 7.6
7/99
71/99
143/220
1.5 0.6 – 3.8
3.1 2.0 – 4.6
0.95 0.7 – 1.2
2/28
39/28
77/117
233/330
1.4 1.1 – 1.7
118/145
1.2 0.3 – 5.8
5.4 3.0 – 9.6
1.4 1.01 – 1.9
1.9
1.4 – 2.4
Interphone Summary
Interphone Release, October 8, 2008
• No increased risk meningioma, parotid
gland tumors
• Doubled risk of gliomas in Denmark,
France, Germany, Japan with 10 yrs of use
• Some increase in acoustic neuroma
Acoustic Neuroma Meta-analysis
Han et al., 2009
• Cell phone use for at
least 10 years had a
2.4-fold of acoustic
neuroma (95% CI =
1.1-5.3)
Need for Industry Records
for independent evaluation
• reduce recall bias and increase statistical
power
• conduct retrospective analyses of first
adopters & typical SAR with geocoding
• evaluate impacts on children and teenagers
• advise regarding engineering redesign
Existing Studies Biased Toward Null
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Insufficient latency time. The time between exposure and
diagnosis of a brain tumor, similar to smoking and lung
cancer could be several decades.
"Regular" cellphone use is defined as once a week for 6
months or more. Would you expect to find lung cancer in
a smoker who had smoked for once a week for 6 months or
more?
No young adults or children included. Because their
brains are more susceptible, they are likely to be
vulnerable.
Methodological Critiques
• Cellphones used in rural areas radiate more power
than in urban areas. Studies have not included rural
users.
• Cordless phones are similar to cellphones yet cordless
phones users are treated as unexposed.
• People who die before they can be interviewed are
excluded. This underestimates risks of most
deadly brain tumors.
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• Interviews conducted in hospital after surgery
• Recall bias (imperfect memory). An Interphone study,
using billing records, has shown that light users
underestimate their use and heavy user overestimates
their use.
Cell Phone Studies
Industry
Funded
Effect
25
No Effect
52
Total
77
(42%)
(32%)
(68%)
Non-Industry105(58%)
Funded
74
31
(70%)
(30%)
Total
99 (54%)
83 (46%)
182
c2 = 24.36 (p< .001)
Odds ratio=0.2 an industry funded study
is 1/5 as likely to report a positive finding compared to an independent one.
(1/29/04)
Source: Lai and Richter
Biological Plausibility
• Alters heat shock proteins
• Increases permeability of blood, brain
barrier
• Epigenetic effects on methylation and DNA
repair
• Some thermal effects
Ethical Questions??
• Apparent release of peer review to attorneys
engaged in litigation
Department of Health “Mobile phones &
Health” Leaflet (October 2006 )
• If you use a mobile phone, you can choose to
minimize your exposure to radio waves.
– keep your calls short
– consider relative SAR values when buying a new phone.
• Radio waves above a certain level can cause heating
effects to the body. International guidelines have been
set to keep exposure to radio waves below that level.
• The UK has a ban on handheld cell phone use while
driving.
U.K. Advice (continued)
• For children and young people (under the age of
16), the UK Chief Medical Officers strongly
advise:
– use mobile phones for essential purposes only
– keep all calls short - talking for long periods prolongs
exposure and should be discouraged
• The UK CMOs recommend that if parents want to
reduce potential risks to children they should
restrict children’s use of mobile phones.
FRANCE, DECEMBER 2008
The Israeli Ministry of Health –
Recommendations for cell phone use (July 2008)
“In general, the Israeli Ministry of Health embraces the guidelines
published by most international entities, which recommend following
the precautionary principle in relation to mobile phone use.
Accordingly, the Israeli Ministry of Health recommends the following:”
Use of a speaker/hands free device or earphones. Reducing the number and
duration of cell phone calls is another simple way of decreasing the exposure.
In areas where the reception is weak, the exposure level increases. Therefore,
one should talk less in these areas.
It is highly recommended that the precautionary rules be followed by children,
who are in general, more sensitive to develop cancer following exposure to
carcinogenic factors.
While driving, it is best to speak as little as possible and, in any case, to follow
regulation B28.
http://www.health.gov.il/pages/default.asp?PageId=4408&catId=838&maincat=46
Center for Environmental Oncology
University of Pittsburgh Cancer Institute –
Recommendations for cell phone use (July 2008)
“Precautionary Principle”
Use of a speaker/hands free device or earphones. Reducing the number and
duration of cell phone calls is another simple way of decreasing the exposure.
In areas where the reception is weak, the exposure level increases. Therefore,
one should talk less in these areas.
It is highly recommended that the precautionary rules be followed by children,
who are in general, more sensitive to develop cancer following exposure to
carcinogenic factors.
http://www.health.gov.il/pages/default.asp?PageId=4408&catId=838&maincat=46
UK, Department of Health
“Mobile phones & Health” Leaflet (October 2006 )
Gaps in scientific knowledge led the
Stewart Group to recommend a
precautionary approach to the use of
mobile phones and base stations.
French Government Proposed
Restrictions on Cell Phones, January,
2009
• Ban advertising to children under 12
• Ban design of phones to be used by those under
six.
• Handsets must be sold with phones
• City of Lyon official advertising campaign to
discourage the use of the phones by children.
Finnish Authorities Warn of Cell Phone
Risks to Children and Those with
Pacemakers
• Use text messages rather than calls
• Use hands-free devices, with phone kept
away from the body,
• Avoid talking in an area with low
connectivity
• Disruption of pacemakers is usually
harmless, but can increase heart beat
Finnish Authorities
Warn of Cell Phone
Risks to Children
“Although research to
date, has not
demonstrated health
effects from mobile
phone’s radiation,
precaution is
recommended for
children as all of the
effects are not
known.”
Many governments advise against
children using cell phones:
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England
France
Germany
Israel
Finland
Bangalore, India
Nick Naylor—Moral Flexibility
Truth is Stranger Than Fiction
• “Gentlemen, practice these words in front of
the mirror: Although we are constantly
exploring the subject, currently there is no
direct evidence that links cell phone usage
to brain cancer.”
For more information
visit:
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preventingcancernow.org
ewg.org
thesimplebody.com
devradavis.com
Center for Environmental Oncology
Leadership and Staff
• Ronald B. Herberman, MD, Director of UPCI Cancer
Centers
• Devra Lee Davis, PhD. MPH, Director
• Maryann Donovan,MPH,PhD,Scientific Director
• Evelyn Talbott, PhD, Epidemiology
• Joel Weissfeld, MD, Epidemiology
• Monica Han, PhD, Post-Doctoral Fellow
• Steven Bodnar, MS, Greening/Community Assessment
• Mary Platt, MBA, Center Administrator
Martin Luther King, Jr.
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Cowardice asks the question, “Is it safe?”
Expediency asks the questions, “Is it politic?”
But Conscience asks the question: “Is it right?”
And there comes a time when one must take a
position that is neither safe, nor politic, nor
popular, but he must do it because Conscience
tells him it is right.”
www.preventingcancernow.org
www.devradavis.com
www.thesimplebody.com