New research indicates that brain cancer risk increases with more years of cell phone and cordless phone use and more hours of use.
Dr. Lennart Hardell and his colleagues in Sweden just published the third in a series of papers
on the use of wireless phones, including cell phones and cordless phones, and the risk
of malignant and non-malignant brain tumors. The latest paper describes a new case-control
study that examines the association between mobile phone use and brain cancer risk.
In these studies, the cases were diagnosed with brain tumors between 2007 and
2009. (1)
The study updates
earlier research from case-control studies conducted by the Hardell group and extends
the prior research by examining the effects of wireless phone use, i.e., cell
phone and cordless phone use, on brain tumor risk for people who have used these
phones for up to 25 or more years.
Overall,
the research found that people who used wireless phones for more than a year were
at 70% greater risk of brain cancer as compared to those who used wireless phones
for a year or less. Those who used wireless phones for more than 25 years were at
greatest risk—300% greater risk of brain cancer than those who used wireless
phones for a year or less.
The total number
of hours of wireless phone use was as important as the number of years of use. A
fourth of the sample used wireless phones for 2,376 or more hours in their
lifetime which corresponds to about 40 minutes a day over ten years. These
heavier users had 250% greater
risk of brain tumors as compared to those who never used wireless phones or used
them for less than 39 hours in their lifetime.
A similar analysis reported in the 13-nation Interphone study funded partly by the World Health Organization found a 182% greater risk of brain cancer among those who used cell phones for 1,640 or more hours in their lifetime.
In the current study, for all
types of wireless phone use, brain cancer risk was found to be greater in the part
of the brain where the exposure to wireless phone radiation was highest—in the
temporal or overlapping lobes of the brain on the side of the head were people
predominantly used their phones.
Given consistent results from multiple case-control studies that long-term use of mobile phones (i.e., ten
or more years) is associated with brain cancer especially near
where the phone is predominantly used, the International Agency for Research on
Cancer should strengthen its 2011 assessment of radiofrequency energy from “possibly
carcinogenic” to “probably carcinogenic” to humans.
More
importantly, governments around the world should heed the results of these
studies. The public must be educated about the need to take simple precautions
whenever using wireless devices. Governments must strengthen regulatory
standards for wireless radiation and must fund research independent of industry
to develop safer technologies.
The paper
was published online in the peer-reviewed journal, International Journal of Oncology. The abstract and a link to this paper appears
below along with the abstracts for the Hardell group’s two prior papers from
this study. All three papers are open access.
(1-3)
References
(1) Lennart Hardell, Michael Carlberg, Fredrik Söderqvist, Kjell
Hansson Mild. Case-control study of the association between malignant brain
tumours diagnosed between 2007 and 2009 and mobile and cordless phone use.
International Journal of Oncology. Published online September 24, 2013.
Abstract
Previous studies have shown a
consistent association between long-term use of mobile and cordless phones and
glioma and acoustic neuroma, but not for meningioma. When used these phones
emit radiofrequency electromagnetic fields (RF-EMFs) and the brain is the main
target organ for the handheld phone. The International Agency for Research on
Cancer (IARC) classified in May, 2011 RF-EMF as a group 2B, i.e. a
‘possible’ human carcinogen. The aim of this study was to further explore the
relationship between especially long-term (>10 years) use of wireless phones
and the development of malignant brain tumours.
We conducted a new case-control study of brain tumour cases of both genders aged 18-75 years and diagnosed during 2007-2009. One population-based control matched on gender and age (within 5 years) was used to each case. Here, we report on malignant cases including all available controls. Exposures on e.g. use of mobile phones and cordless phones were assessed by a self-administered questionnaire. Unconditional logistic regression analysis was performed, adjusting for age, gender, year of diagnosis and socio-economic index using the whole control sample.
Of the cases with a malignant brain tumour, 87% (n=593) participated, and 85% (n=1,368) of controls in the whole study answered the questionnaire. The odds ratio (OR) for mobile phone use of the analogue type was 1.8, 95% confidence interval (CI)=1.04‑3.3, increasing with >25 years of latency (time since first exposure) to an OR=3.3, 95% CI=1.6-6.9. Digital 2G mobile phone use rendered an OR=1.6, 95% CI=0.996-2.7, increasing with latency >15-20 years to an OR=2.1, 95% CI=1.2-3.6. The results for cordless phone use were OR=1.7, 95% CI=1.1-2.9, and, for latency of 15-20 years, the OR=2.1, 95% CI=1.2-3.8. Few participants had used a cordless phone for >20-25 years. Digital type of wireless phones (2G and 3G mobile phones, cordless phones) gave increased risk with latency >1-5 years, then a lower risk in the following latency groups, but again increasing risk with latency >15-20 years. Ipsilateral use resulted in a higher risk than contralateral mobile and cordless phone use. Higher ORs were calculated for tumours in the temporal and overlapping lobes. Using the meningioma cases in the same study as reference entity gave somewhat higher ORs indicating that the results were unlikely to be explained by recall or observational bias.
This study confirmed previous results of an association between mobile and cordless phone use and malignant brain tumours. These findings provide support for the hypothesis that RF-EMFs play a role both in the initiation and promotion stages of carcinogenesis.
http://www.spandidos-publications.com/10.3892/ijo.2013.2111
We conducted a new case-control study of brain tumour cases of both genders aged 18-75 years and diagnosed during 2007-2009. One population-based control matched on gender and age (within 5 years) was used to each case. Here, we report on malignant cases including all available controls. Exposures on e.g. use of mobile phones and cordless phones were assessed by a self-administered questionnaire. Unconditional logistic regression analysis was performed, adjusting for age, gender, year of diagnosis and socio-economic index using the whole control sample.
Of the cases with a malignant brain tumour, 87% (n=593) participated, and 85% (n=1,368) of controls in the whole study answered the questionnaire. The odds ratio (OR) for mobile phone use of the analogue type was 1.8, 95% confidence interval (CI)=1.04‑3.3, increasing with >25 years of latency (time since first exposure) to an OR=3.3, 95% CI=1.6-6.9. Digital 2G mobile phone use rendered an OR=1.6, 95% CI=0.996-2.7, increasing with latency >15-20 years to an OR=2.1, 95% CI=1.2-3.6. The results for cordless phone use were OR=1.7, 95% CI=1.1-2.9, and, for latency of 15-20 years, the OR=2.1, 95% CI=1.2-3.8. Few participants had used a cordless phone for >20-25 years. Digital type of wireless phones (2G and 3G mobile phones, cordless phones) gave increased risk with latency >1-5 years, then a lower risk in the following latency groups, but again increasing risk with latency >15-20 years. Ipsilateral use resulted in a higher risk than contralateral mobile and cordless phone use. Higher ORs were calculated for tumours in the temporal and overlapping lobes. Using the meningioma cases in the same study as reference entity gave somewhat higher ORs indicating that the results were unlikely to be explained by recall or observational bias.
This study confirmed previous results of an association between mobile and cordless phone use and malignant brain tumours. These findings provide support for the hypothesis that RF-EMFs play a role both in the initiation and promotion stages of carcinogenesis.
http://www.spandidos-publications.com/10.3892/ijo.2013.2111
(2) Lennart Hardell, Michael Carlberg, Fredrik Söderqvist, Kjell Hansson Mild.
Pooled analysis of case-control studies on acoustic neuroma diagnosed 1997-2003
and 2007-2009 and use of mobile and cordless phones. International
Journal of Oncology. 43(4):1036-1044. October 2013.
Abstract
Abstract
We previously conducted a case-control study of acoustic neuroma. Subjects of both genders aged 20-80 years, diagnosed during 1997-2003 in parts of Sweden, were included, and the results were published. We have since made a further study for the time period 2007-2009 including both men and women aged 18-75 years selected from throughout the country. These new results for acoustic neuroma have not been published to date.
Similar methods were used for both study periods. In each, one population-based control, matched on gender and age (within five years), was identified from the Swedish Population Registry. Exposures were assessed by a self-administered questionnaire supplemented by a phone interview. Since the number of acoustic neuroma cases in the new study was low we now present pooled results from both study periods based on 316 participating cases and 3,530 controls. Unconditional logistic regression analysis was performed, adjusting for age, gender, year of diagnosis and socio-economic index (SEI).
Use of mobile phones of the analogue type gave odds ratio (OR) = 2.9, 95% confidence interval (CI) = 2.0-4.3, increasing with >20 years latency (time since first exposure) to OR = 7.7, 95% CI = 2.8-21. Digital 2G mobile phone use gave OR = 1.5, 95% CI = 1.1-2.1, increasing with latency >15 years to an OR = 1.8, 95% CI = 0.8-4.2. The results for cordless phone use were OR = 1.5, 95% CI = 1.1-2.1, and, for latency of >20 years, OR = 6.5, 95% CI = 1.7-26. Digital type wireless phones (2G and 3G mobile phones and cordless phones) gave OR = 1.5, 95% CI = 1.1-2.0 increasing to OR = 8.1, 95% CI = 2.0-32 with latency >20 years. For total wireless phone use, the highest risk was calculated for the longest latency time >20 years: OR = 4.4, 95% CI = 2.2-9.0. Several of the calculations in the long latency category were based on low numbers of exposed cases. Ipsilateral use resulted in a higher risk than contralateral for both mobile and cordless phones. OR increased per 100 h cumulative use and per year of latency for mobile phones and cordless phones, though the increase was not statistically significant for cordless phones. The percentage tumour volume increased per year of latency and per 100 h of cumulative use, statistically significant for analogue phones. This study confirmed previous results demonstrating an association between mobile and cordless phone use and acoustic neuroma.
(3) Michael Carlberg, Fredrik Söderqvist, Kjell Hansson Mild,
and Lennart Hardell. Meningioma patients diagnosed 2007–2009 and the
association with use of mobile and cordless phones: a case–control study. Environmental
Health 2013, 12:60. Published online Jul 19, 2013.
Abstract
Background
To study the association between use of wireless phones and
meningioma.
Methods We performed a case–control study on brain tumour
cases of both genders aged 18–75 years and diagnosed during 2007–2009. One
population-based control matched on gender and age was used to each case. Here
we report on meningioma cases including all available controls. Exposures were
assessed by a questionnaire. Unconditional logistic regression analysis was
performed.
Results In total 709 meningioma cases and 1,368 control
subjects answered the questionnaire. Mobile phone use in total produced odds
ratio (OR) = 1.0, 95% confidence interval (CI) = 0.7-1.4 and cordless phone use gave OR = 1.1, 95% CI = 0.8-1.5.
The risk increased statistically significant per 100 h of cumulative use
and highest OR was found in the fourth quartile (>2,376 hours) of
cumulative use for all studied phone types. There was no statistically
significant increased risk for ipsilateral mobile or cordless phone use, for
meningioma in the temporal lobe or per year of latency. Tumour volume was not
related to latency or cumulative use in hours of wireless phones.
Conclusions
No conclusive evidence of an
association between use of mobile and cordless phones and meningioma was found.
An indication of increased risk was seen in the group with highest cumulative
use but was not supported by statistically significant increasing risk with
latency. Results for even longer latency periods of wireless phone use than in
this study are desirable.
