Study finds no genotoxic effects from 900 MHz fields
A Swiss study has failed to find any genotoxic effects of RF fields on cells of the yeast Saccharomyces cerevisiae. The authors used 900 MHz fields that closely matched the Global System for Mobile Communication (GSM). Specific absorption rates were 0.13 and 1.3 W/kg. Several different tests were performed, and there was no evidence of increased mutation rates or genomic instability.
Gos P, Eicher B, Kohli J, Heyer W-D. No mutagenic or recombinogenic
effects of mobile phone fields at 900 MHz detected in the yeast Saccharomyces
cerevisiae. Bioelectromagnetics 2000;21:515-523.
A recent study examined the effects of 1.25 GHz high peak power microwaves in Rhesus monkeys. The animals were exposed for 4 hours per day and 3 days per week for 3 weeks. The authors examined the retina of the monkeys using photographs, blood vessel dye studies, measurement of electrical changes in the retina, and microscopical examination of the eye tissues. Several microwave powers were used. The authors stated that "retinal injury is very unlikely at 4W/kg. Functional changes that occur at higher R-SAR are probably reversible".
Lu S-T, Mathur SP, Stuck B, Zwick H, et al. Effects of high peak power
microwaves on the retina of the Rhesus monkey. Bioelectromagnetics 2000;21:439-454.
Oftedal and colleagues have published a paper on a 1995 study of mobile phone users in Norway and Sweden. Of those who completed a questionnaire asking about symptoms associated with mobile phone use, 31% in Norway and 13% in Sweden reported experiencing at least one symptom. The authors point out that this does not necessarily imply a causal relationship between phone use and the symptom.
For more details, see "Research - Epidemiology".
Oftedal G, Wilen J, Sandstrom M, Mild KH. Symptoms experienced in connection
with mobile phone use. Occup Med 2000;50:237-245.
In "What's New" of February, 2000, we discussed a study from the University of Zurich that showed that exposure to EMF during sleep altered sleep onset latency and also EEG patterns (see also "Health - Brain Function, Borbely et al.). The same group now reports that exposure to EMF before sleep affects EEG patterns during subsequent sleep. A commentary in the same issue of NeuroReport emphasises that the mechanisms for these changes remain unclear, and that it has not been established that there are any long-term effects on human brain function from EMF exposure.
For more details, see "Research - Clinical -EEG".
Reference: Huber R, Graf T, Cote KA, Wittman L, et al. Exposure to pulsed high-frequency electromagnetic field during waking affects human sleep EEG. NeuroReport 2000;11:3321-3325.
Petrides M. Exposure to electromagnetic fields by using cellular telephones and its influence on the brain. NeuroReport 11:3321-3325.