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16/10/2013 - New papers show phones cause brain tumours
Two important mobile phone and cancer papers from Hardell, et al.
RF-EMF emissions from wireless phones are class 1 human carcinogens
Using the long-established and respected Bradford Hill criteria for assessing causality, this paper shows that RF-EMF exposure from mobile (and cordless) phones should be regarded as an IARC class 1 human carcinogen (cancel causing agent). Current guidelines for exposure need
to be urgently revised.
Wireless phones, i.e. mobile phones and cordless phones, emit radiofrequency electromagnetic
fields (RF-EMF) when used. An increased risk of brain tumors is a major concern. The International Agency for Research on Cancer (IARC) at the World Health Organization (WHO) evaluated the carcinogenic effect to humans from RF-EMF in May 2011. It was concluded that RF-EMF is a group 2B, i.e. a "possible", human carcinogen.
Bradford Hill gave a presidential address at the British Royal Society of Medicine in 1965 on the association or causation that provides a helpful framework for evaluation of the brain tumour risk from RF-EMF.
All nine issues on causation according to Hill were evaluated. Regarding wireless phones, only studies with long-term use were included. In addition, laboratory studies and data on the incidence of brain tumours were considered.
The criteria on strength, consistency, specificity, temporality, and biologic gradient for evidence of increased risk for glioma and acoustic neuroma were fulfilled. Additional evidence came from plausibility and analogy based on laboratory studies.
Regarding coherence, several studies show increasing incidence of brain tumours, especially in the most exposed area. Support for the experiment came from antioxidants that can alleviate
the generation of reactive oxygen species involved in biologic effects, although a direct mechanism for brain tumor carcinogenesis has not been shown. In addition, the finding of no increased risk for brain tumors in subjects using the mobile phone only in a car with an external antenna is supportive evidence. Hill did not consider it was essential, or even very likely, that all the listed criteria were likely to be fulfilled.
Ref: Lennart Hardell and Michael Carlberg, Using the Hill viewpoints from 1965 for evaluating strengths of evidence of the risk for brain tumors associated with use of mobile and cordless phones, Rev Environ Health 2013-0006, De Gruyter; DOI 10.1515
Case-control study of the association between malignant brain tumours diagnosed between 2007 and 2009 and mobile and cordless phone use
This new study confirms previous results of an association between mobile and cordless phone use and malignant brain tumours. The findings provide support for the hypothesis that RF-EMFs play a role both in the initiation and promotion stages of carcinogenesis.
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 these phones are used they emit radiofrequency electromagnetic fields (RF-EMFs) and the brain is the main target organ for the handheld phone emissions.
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.
The researchers 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 for 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 (GSM) mobile phone use rendered an OR=1.6, 95% CI=0.996-2.7,
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.
Ref: Hardell L, Carlberg M, Soderqvist F, Mild KH. Case-control study of the association between malignant brain tumours diagnosed between 2007 and 2009 and mobile and cordless phone use,
Int J Oncol. 2013 Sep 24. doi: 10.3892/ijo.2013.2111. [Epub ahead of print]