Mobile Phones and Blood-Brain Barrier

The available scientific evidence is insufficient to dismiss or to support claims of a health risk in humans

Dariusz Leszczynski

STUK - Radiation and Nuclear Safety Authority, Helsinki, Finland

phone 358-9-75988694, fax: 358-9-75988464, e-mail: dariusz.leszczynski@stuk.fi

Abstract

One of the potential health risks of the mobile phone radiation (RF-EMF) is induction of the leakage of blood-brain barrier (BBB). Clarification of this issue has been listed as one of the research priorities by the World Health Organization's Electro Magnetic Fields Project (WHO-EMF Project) (Repacholi 1998). At the present there are no epidemiological or human volunteer studies that would address the issue of RF-EMF effect on BBB. Therefore, in evaluating the potential risk to human health, scientific panels have had to rely on the evidence provided by animal and in vitro studies (The Royal Society of Canada 1999, Jokela et al. 1999, Independent Expert Group on Mobile Phones 2000, French Health Directorate 2001, Health Council of the Netherlands 2002). Based on this evidence it has been concluded:

· in 2000 - “Stewart Commission” (Independent Expert Group on Mobile Phones 2000) - “The available evidence for an effect of RF exposure on the blood-brain barrier is inconsistent and contradictory. Recent, well-conducted studies have not reported any effects.”,

· in 2002 - “Dutch Commission” (Health Council of the Netherlands 2002) - “A number of studies from the 1970s and 1980s seem to indicate that exposure to electromagnetic fields affects the permeability of the blood-brain barrier. However, recent research has been unable to reproduce these effects. The Committee is of the opinion that there are no scientific grounds to assume the existence of such effects.”.

In spite of these no-risk-to-humans conclusions, the recently published in vitro study (Leszczynski et al. 2002) and animal study presented at several scientific meetings (Töre et al. 2001, Töre et al. 2002) have suggested that RF-EMF exposure might have effect on BBB. Hypothesis has been proposed that RF-EMF-exposure-induced increase in phosphorylation of stress response protein hsp27 might be molecular event that could cause the shrinkage of endothelial cells and increase their pinocytosis and in this way to induce BBB leakage (Leszczynski et al. 2002, Leszczynski 2002).

Considering the weaknesses of the presently available scientific evidence, any “final conclusions” as to the potential effect of mobile phone radiation on blood-brain barrier are premature. The presently available scientific evidence, that is based on in vitro or on animal studies, does not provide clear answer whether mobile phone radiation alters permeability of blood-brain barrier or does not have any effect. Human laboratory studies are urgently needed to clarify this issue.

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