Zweden: Opnieuw een studie over de doorlaatbaarheid van de bloed hersen barrire (Upd+Ext)

zondag, 16 november 2008 - Categorie: Onderzoeken

Bijzonder is dat de onderzoekers hebben vastgesteld dat lagere intensiteiten een groter effect kunnen hebben. Deze omgekeerde dosis response relatie zal onderwerp moeten zijn van vervolgonderzoek, aldus de Zweedse wetenschappers.

Zie ook de wetenschappelijke analyse en genoemde consequenties -met name de versterkte aanwijzingen voor hersenschade bij langdurig mobielgebruik- onder:
www.powerwatch.org.uk/news/20081113_blood_brain_barrier.asp .


Bron: Cindy Sage, CHE-EMF Working Group

A new study from Sweden has been published by Eberhardt et al, and is
co-authored by veteran EMF
researchers Leif Salford and Bertil RR Persson of Lund University.

The study reports that cell phone GSM frequency exposure induces
pathological leakage of albumin across the blood-brain barrier. Such
effects have been reported in prior studies (for example, Salford 2003
and Schirmacher, 2007).

The blood-brain barrier is a critical structure in the brain that
separates the flow of blood through the brain from the brain matter
itself. Blood contains toxins being carried to excretory organs and
also certain molecules like albumin that can be lethal to brain
tissue. Exposure to extraordinarily small RF levels on the order of
may open the blood-brain barrier, making it leaky and
allowing toxins and molecules to cross directly into the brain, which
in turn can cause nerve cell damage and neuron death.

Eberhard et al (2008) report that two-hour exposures to cell phone GSM
microwave RF resulted in leakage of albumin across the blood-brain
barrier (BBB) and in neuron damage. Neuronal albumin uptake was
significantly correlated to occurrence of damaged neurons when
measured at 28 days post-exposure. The lowest exposure level was 0.12
mW/kg (0.00012 W/kg) for two hours. The highest exposure level was
120 mW/kg (0.12 W/kg). The weakest exposure level showed the greatest
effect in opening the BBB, and in neuron damage and death.

The current FCC exposure limit is 1.6 W/kg and the ICNIRP exposure
limit is 2 W/kg.

The most remarkable observation in our studies on the effects of
microwaves on the BBB is the fact that the lower SAR values (around 1
mW/kg) give rise to more pronounced albumin leakage than the higher
SAR values. If increase in dose had led to increased response, we feel
that the risk of cellular telephones, base-stations, and other
RF-emitting sources could be managed by reduction of their emitted
energy. The indications from our study that the weakest fields are
the biologically most harmful, poses a complicated problem. The most
pronounced BBB-opening effect of the mobile telephone may not be in
the most superficial layers of the brain, but several centimeters deep
in central cerebral structures. It seems quite possible that
bystanders in the vicinity of mobile phone users may be affected
through passive GSM exposure, as well as larger groups exposed from
distant base-stations. More, substantial research is needed,
however, before reliable dose-response relationships can form the
basis for recommendations for future exposure limit values that take
into account non thermal effects of microwaves from mobile
communications on the human brain.

JL Eberhardt BRR Persson AE Brun LG Salford LOG Malmgren, 2008.
Blood-brain barrier permeability and nerve cell damage in rat brain 14
and 28 days after exposure to microwaves from GSM mobile phones.
Electromagnetic Biology and Medicine 27:215-229.
DOI:10.10801536370802344037



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