April 2007

Comparison of methods used to assess cell phone exposure

One of the major challenges that researchers face when conducting epidemiological studies of cell phones is the difficulty in accurately assessing the exposure of an individual to the radiofrequency radiation from the phone. The two methods most commonly employed are self-reported use and using data on subscriptions that are supplied by a network provider. Schüz and Johansen compared these two methods, using data from two studies that they were able to cross-link. They found "fair" agreement between the two methods. However, they point out the limitations of both methods, and argue that these limitations can be minimized in prospective studies, with exposure estimation based on traffic records on current use of a cellular telephone.
For more on this subject, see "Research - Exposure assessment".

Reference: Schüz J, Johansen C. A comparison of self-reported cellular telephone use with subscriber data: Agreement between the two methods and implications for risk estimation. Bioelectromagnetics 2007;28:130-136.

Benevento Resolution

The International Commission for Electromagnetic Safety (ICEMS) held a conference entitled The Precautionary Approach: Rationale, Legislation, and Implementation.The City of Benevento, Italy, hosted the conference on February 22-24, 2006. The meeting was dedicated to W. Ross Adey. The scientists at the meeting drew attention to their concern that electromagnetic fields (EMFs) can have adverse effects, and made a number of recommendations to minimize exposure to EMFs.

The Resolution can be found at:
Electromagnetic Biology and Medicine 2006;25:197-200.


RFR exposure and heart rate variability

Parazzini and colleagues tested the effect of radiofrequency radiation (RFR) exposure at 900 MHz on the heart rate variability (HRV) on young adults. The found no effect on the main outcome of R-R interval on the electrocardiogram, and on most of the other parameters, but a weak effect on some. This latter effect was suggestive of an effect on the sympathetic component of the autonomic nervous system.
For more, see "Research - Clinical - Cardiovascular".

Reference: Parazzini M, Parazzini P, Tognola G, Thuroczy G, et al. Electromagnetic fields produced by GSM cellular phones and heart rate variability. Bioelectromagnetics 2007;28:122-129.
Go to summary>

Norwegian Interphone study of intracranial tumours

Another Interphone study - this one from Norway - has been published. There was no evidence from the study that cell phone use is associated with an increased risk of gliomas, meningiomas, or acoustic neuromas. The authors discuss the common limitations of epidemiological studies, particularly case-control studies. These include selection and recall bias, and misclassification. They also caution that the time interval since the introduction of cell phone use may be too short to detect possible effects of cell phone use.
For more, see "Research - Epidemiology", and "Research Programs - Interphone study".

Reference: Klaeboe L, Blaasaas KG, Tynes T. Use of mobile phones in Norway and risk of intracranial tumours. Eur J Cancer Prev 2007;16:158-164
Go to summary>


Correlation of health indicators with population density and power output from cell phones

Hallberg reports that a variety of health indicators have shown a decline since 1997 in Sweden. In an ecological analysis he reports that people in sparsely populated counties had more illness, and that the indicators correlated strongly with estimated cell phone area coverage and power output.

An ecological analysis is the weakest type of epidemiological study. It is subject to a bias known as the ecological fallacy (Last JM, A Dictionary of Epidemiology, 1988), which may occur because an association observed between variables on an aggregate level does not necessarily represent the association that exists at an individual level. There may be a number of factors that can explain an observed correlation. For more, see "Research - Exposure Assessment".

Reference: Hallberg O. Adverse health indicators correlating with sparsely populated areas in Sweden. Eur J Cancer Prev 2007;16:71-76.
Go to summary>

Development of an EMF hypersensitivity questionnaire

Eltiti and colleagues from the UK have developed an electromagnetic hypersensitivity questionnaire. The authors consider that the scale provides an index of the type and severity of symptoms commonly experienced by people believing themselves to be EHS and a screening tool that researchers can use to pre-select the most sensitive individuals to take part in their research.
For more, see "Clinical - Others- General health symptoms".

Reference: Eltiti S, Wallace D, Zougkou K, Russo R, et al. Development and evaluation of the electromagnetic hypersensitivity questionnaire. Bioelectromagnetics 2007;28:137-151.
Go to summary>

WHO Workshop report

Valberg and colleagues have published a report on a "Workshop on Base Stations and Wireless Networks" that was convened by the World Health Organization. The report details sources of radiofrequency radiation (RFR) and their exposure levels. It discusses mechanisms that would be required of RF energy to change physiological function, initiate dysfunction, or cause the onset of disease in humans or animals. It briefly summarizes research that that has been done on the health effects of RFR exposure. The report also assesses the problems in risk communication in everyday life.

Reference: Valberg PA, van Deventer TE, Repacholi MH. Workshop report: Base stations and wireless networks - radiofrequency (RF) exposures and health consequences. Environ Health Perspect 2007;115:416-424.



Home             Links              Sitemap               Contact Us
© McLaughlin Centre for Population Health Risk Assessment